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Sample records for dosimetria osl luminescencia

  1. BeOSL system for personal dosimetry : dosimetric characteristics and practical application; Sistema BeOSL para dosimetria personal : caracteristicas dosimetricas y la aplicacion practica

    Energy Technology Data Exchange (ETDEWEB)

    Mende, E. [Helmholtz Zentrum Munchen, German Research Center for Environmental Health, Working Group Engineering, D-85764 Neuherberg (Germany)

    2015-10-15

    Full text: BeOSL system of Dosimetric s is very easy to use, assimilate and maintain. Our dosimeter defines a milestone in the supervision of personal equivalent dose of Hp (10) and Hp (0.07) it covers the range of total energy of 16 KeV to 10 MeV. For this energy range is exceptional in its energy dependence for official personal dosimetry. The BeOSL system consists of two modules, one of them is the BeOSL reader that measures the radiation exposure using the latest technology, optically stimulated luminescence (OSL). The reading is extremely fast; it does not require consumables such as nitrogen or other. The detector material is beryllium oxide (Be O); this is an OSL material tissue equivalent and therefore is ideal for personal dosimetry. The BeOSL technology allows multiple readings of the dosimeter (re-read) to verify the dose or archive the dosimeter. One of the biggest advantages of BeOSL system is its modular concept allows the system to run as a manual solution or as a complete automated robotic system, which can be filled with up to 5,000 dosimeters as bulk cargo. (Author)

  2. Characterization of Al{sub 2}O{sub 3}:C dosemeters for photon dosimetry using OSL technique; Caracterizacao de dosimetros de Al{sub 2}O{sub 3}:C para dosimetria de fotons utilizando a tecnica OSL

    Energy Technology Data Exchange (ETDEWEB)

    Villani, D.; Almeida, S.B.; Campos, L.L., E-mail: dvillani@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2016-07-01

    The optically stimulated dosimetry (OSL) has gained prominence in clinical and academic applications in Brazil. In this paper, we present results of the characterization OSL dosimeters Al{sub 2}O{sub 3}:C (TLD-500) manufactured by Rexon™ Components and TLD Systems in a RISØ reader, model TL/OSL-DA-20 for dosimetry of high-energy photon beams. All reader parameters, and its variations were evaluated. (author)

  3. Tl and OSL dosimetry of diamond films CVD pure and unpurified with boron-carbon; Dosimetria Tl y OSL de peliculas de diamante CVD puras e impurificadas con boro-carbono

    Energy Technology Data Exchange (ETDEWEB)

    Melendrez, R.; Pedroza M, M.; Chernov, V.; Ochoa N, J.D.; Bernal, R.; Barboza F, M. [CIF, UNISON, A.P. 5-088, 83190 Hermosillo, Sonora (Mexico); Castaneda, B. [Departamento de Fisica, Universidad de Sonora, Apdo. Postal 1626, Hermosillo, Sonora (Mexico); Goncalves, J.A.N.; Sandonato, G.M. [Laboratorio Associado de Plasma, Instituto Nacional de Pesquisas Espaciais C.P. 515- 12201 -970, Sao Jose dos Campos, SP (Brazil); Cruz Z, E. [Instituto de Ciencias Nucleares, UNAM, Apdo. Postal 70-543, 04510 Mexico D.F. (Mexico); Preciado F, S.; Cruz V, C.; Brown, F. [Departamento de Investigacion en Polimeros y Materiales de la Universidad de Sonora, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Schreck, M. [Universitaet Augsburg, Institut fuer Physik D-86135 Augsburg (Germany)

    2004-07-01

    The diamond is a material that possesses extreme physical properties, such as its hardness to the radiation, its low chemical reactivity besides its equivalence to the human tissue, which qualify him as an ideal material for radiation dosimetry. In this work, it was studied the thermal and optically stimulated response (Tl and OSL) of polycrystalline diamond films grown by the technique of CVD pure and contaminated with Boron-carbon (B/C) with the intention of characterizing their efficiency like a dosemeter for radiation in a range of 0 - 3000 Gy. For the case of the films without impurities, the Tl curve presents four main peaks, two of them in an interval of temperatures of 150-200 C and other two additional around of 250-400 C. The dependence of the response of integrated Tl and that of OSL always maintained a lineal relationship with the exhibition dose up to 100 Gy. The behavior of the films contaminated with B/C (2000 - 20000 ppm) was established through experiments that involved the signal of OSL and their relationship with the Tl response. It was found that this processes are correlated, since the electrons caught in the traps of low temperature (50 - 250 C) of the Tl they are the electrons that recombining with more probability to provide the signal of OSL. According to these results it is possible to propose the diamond films as a good candidate for dosimetry to, using the traditional technique of Tl so much as well as the but recent of OSL. (Author)

  4. Intercomparison of dispersed radiation readings among film dosimetry, electronic and OSL with X-rays for low dose; Intercomparacion de lecturas de radiacion dispersa entre dosimetria film, electronica y OSL con rayos X para dosis bajas

    Energy Technology Data Exchange (ETDEWEB)

    Andisco, D. [Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, C1121AAA Buenos Aires (Argentina); Blanco, S. [CONICET, Saavedra 15, C1083ACA Buenos Aires (Argentina); Bourel, V.; Schmidt, L. [Universidad Favaloro, Facultad de Ciencias e Ingenieria, Solis 453, C1078AAI, Buenos Aires (Argentina); Di Risio, C., E-mail: dandisco@fmed.uba.ar [Universidad de Belgrano, Facultad de Ingenieria, Zabala 1837, C1426DQG, Buenos Aires (Argentina)

    2014-08-15

    One of the personal dosimetry methods more used for several decades is the dosimetry type film, characterized to possess readings with certain margin of trust. Today other methods exist that many times are presupposed more reliable due to the nature of the detection like the electronic dosimeters or the OSL (Optically Stimulated Luminescence) dosimetry. With the purpose of comparing different methods and to can determining the existent differences among each method has been carried out an intercomparison assay. The different dosimeters have been exposed to dispersed radiation generated by a Hemodynamics equipment of the type -arch in C- and a dispersing system of the primary beam. Film dosimeters have been used; OSL (In Light), OSL (Nano Dots) and Electronic with the purpose of knowing and to valorize the existent differences among its readings. Always, the intercomparison exercises have demonstrated to be an useful tool when establishing the measurement capacity and the quality of the results emitted by the laboratories of personal dosimetry services. Also, this type of assays allows obtaining quality indicators of the laboratory performance and they are habitual part of the procedures for accreditation of the same ones. The Optically Stimulated Luminescence is a technology that has grown in Argentina so much in the area of personal dosimetry as in dosimetry in vivo (radiotherapy area). In this intercomparison study, the answers corresponding to each technology were looked for oneself irradiation of the disperse type, that is to say, of very low energy. (Author)

  5. Development and implementation of In-vivo dosimetry with OSL in special techniques (IMRT, TBI, TSE); Desarrollo e implementacion de dosimetria In-vivo con OSL en tecnicas especiales (IMRT, TBI, TSE)

    Energy Technology Data Exchange (ETDEWEB)

    Bourel, V., E-mail: vbourel@favaloro.edu.ar [Universidad Favaloro, Buenos Aires (Argentina)

    2015-10-15

    generalized skin diseases. The characterization of the nano Dots dosimeters in terms of dose response, dose rate, angulation and other parameters in measuring conditions is the essential step before beginning the ultimate goal. The nano Dots showed their capacity for use In-vivo dosimetry, after tests on phantoms for both characterization and for treatment simulation. Finally, in clinical practice results in the three irradiation techniques raised they showed highly satisfactory results with acceptable deviations and comparable with existing previous techniques, proving the feasibility of conducting In-vivo dosimetry with OSL easily and efficiently. (Author)

  6. Comparative study of different Al{sub 2}O{sub 3}:C dosimeters using OSL technique for dosimetry on Volumetric Modulated Arc Radiotherapy Treatment (VMAT); Estudo comparativo de diferentes dosimetros de Al{sub 2}O{sub 3}:C pela tecnica OSL na dosimetria de tratamentos Radioterapicos por Arco Modulado Volumetrico (VMAT)

    Energy Technology Data Exchange (ETDEWEB)

    Villani, Daniel; Campos, LetIcia L., E-mail: dvillani@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Mancini, Anselmo; Haddad, Cecilia M.K. [Hospital Sirio-Libanes, Sao Paulo, SP (Brazil). Centro de Radioterapia

    2016-07-01

    In modern radiotherapy, the VMAT technique has become a successful treatment alternative. Due to its complexity, a quality assurance program must be established by evaluating, among other items, the dosimetric factors. This paper aims to compare the performance between the OSL aluminum oxide (Al{sub 2}O{sub 3}:C) nanoDot™ dosimeters (Inlight™ system) manufactured by Landauer Inc. and TLD-500 Al{sub 2}O{sub 3}:C dosimeters manufactured by Rexon™ for VMAT dosimetry using an anthropomorphic phantom. The results showed that both type of Al{sub 2}O{sub 3}:C dosimeters presented good repeatability and agreement between the doses measured and calculated by planning system. However, the need of sophisticated readers to OSL analysis of the TLD-500, turns it less practical for routine usage, comparing to Inlight™ system. (author)

  7. Evaluation of aluminum oxide dosimeters using OSL technique in dosimetry of clinical photon beams on volumetric modulated arc treatment; Avaliacao de dosimetros de oxido de aluminio pela tecnica OSL na dosimetria de campos de fotons clinicos utilizados no tratamento radioterapico em arco modulado volumetrico

    Energy Technology Data Exchange (ETDEWEB)

    Villani, Daniel

    2017-07-01

    Treatment using Volumetric Modulated Arc Radiation Therapy is the most modern modality of conformational radiotherapy so that, with the overlapping of several fields, the dose distributions provide a perfect conformation to the tumor, reducing the probability of complications in adjacent normal tissues. In this sense, many efforts are being invested to improve dose distribution compliance as well as the integration of imaging techniques for tumor screening and correction of inter and intrafraction variations. To this end, an intensive monitoring of the quality of the processes and a quality assurance program are fundamental for patient safety and compliance with current legislation; besides the use of different dosimetry methodologies for intercomparison and validation of the results. The aim of this study is to evaluate and compare the performance of aluminum oxide (Al{sub 2}O{sub 3}:C) OSL dosimeters manufactured by Landauer Inc. with those produced by Rexon™ in the dosimetry of high energy photon clinical bundles used in Volumetric Modulated Arc Therapy - (VMAT) using different simulating objects. The dosimeters were characterized for gamma radiation of the {sup 60}Co and for clinical photon beams of 6 MV typical of treatments by VMAT under conditions of electronic equilibrium and maximum dose respectively. Performance tests of the TL and OSL readers used and repeatability of the samples were evaluated. After all tests, the dosimeters were irradiated in the simulation of different radiotherapy treatments by VMAT and their responses compared to the planning system. All types of dosimeters presented satisfactory results in verifying the doses of this type of planning simulation. The Al{sub 2}O{sub 3}:C dosimeters presented compatible results and validated by the other dosimeters and ionization chamber. Regarding the best technique, the OSL InLight commercial system presents greater practicality and versatility for use and application in the clinical routine

  8. Development of an Equipment for Measuring OSL

    International Nuclear Information System (INIS)

    Chung, Ki Soo; Choe, Hong Soo

    2010-05-01

    A measurement system optically simulated luminescence (OSL) and thermoluminescence (TL) is developed. The system is composed by stimulation light part assembled by 3 ea of high brightness blue LEDs, temperature control system which can be controlled from room temperature to 300 .deg. C and filter package for separation of OSL and stimulation light with GG-420 and U-340 optical filters. The system was tested using Al 2 O 3 C OSL samples and a typical OSL curves were obtained. In addition, several OSL curves from LiAlO 2 C (a candidate of new OSLD material) were obtained and analyzed. A new algorithm for analysis of OSL curve and software (TOLAnal, Windows based) is developed and tested

  9. Validation and dosimetric evaluation employing the techniques of TL and OSL of thermoluminescent materials for application in the dosimetry of clinical beams of electrons used in total irradiation of the skin - TSI; Validação e avaliação dosimétrica empregando as técnicas de TL e OSL de materiais termoluminescentes para aplicação na dosimetria de feixes clínicos de elétrons utilizados na irradiação total da pele

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Shirlane Barbosa de

    2017-07-01

    In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance program that should be an integral part of the radiotherapy departments. TSI dosimetry is difficult because of the complexity of the treatment in assessing dose uniformity and measuring the dose absorbed at shallow depths throughout the skin surface extent, resulting in a wide variation in dose distribution. The TLDs have proven to be very useful for the distribution and verification of the dose prescribed for the patient as the dose may differ from place to place due to patient body geometry, overlapping of structures and asymmetries of the radiation field. The use of TLDs in vivo can identify variations in the prescribed dose because its measurement accuracy and great precision. Several types of dosimeters have been used in the radiotherapy sectors, the most commonly used are Lithium Fluride (TLD-100), where it obtains a long history in this type of application. New dosimetric materials have gained great importance in the dosimetry of clinical electron beams, such as Dysprosium-doped Calcium Sulphate (TL) and Carbon doped (OSL) based Aluminum Oxide, This work evaluates the performance of the respective thermoluminescent dosimeters and the optically stimulated luminescence in the dosimetry of clinical electron beams used in total irradiation of the skin. (author)

  10. Emergency OSL dosimetry with commonplace materials

    International Nuclear Information System (INIS)

    Sholom, S.; McKeever, S.W.S.

    2014-01-01

    Several commonplace materials were studied as possible emergency optically stimulated luminescence (OSL) dosimeters. The materials included: paper currency (banknotes) and coins of different denomination and from different countries; plastic cards of different types (credit and debit cards, driver's license cards, membership cards, etc.), parts and details of clothing and shoes as well as samples of different fabrics. The samples displayed significant variability in their OSL properties. They differed in the intensity of the initial ‘native’ signal; the bleaching time of the OSL signal; the sensitivity to light of different wavelengths; the fading rate of OSL signals, etc. Procedures of OSL analysis were proposed to account for this variety. Values of the minimum measurable dose (MMD) were below 2 Gy for most tested samples if OSL measurements were conducted within one week of exposure and the samples were kept in dark since exposure (except samples of shoes that were kept under environmental light). The OSL signals in banknotes appear to originate from compounds containing aluminum, silicon, calcium and titanium – these elements were detected using X-ray microanalysis. For coins, the source of the OSL signals is speculated to be small particles of quartz, which were detected on the coins' surfaces. The X-ray microanalysis spectra from fabrics and shoes revealed sodium, aluminum, titanium, iron and nickel as elements that appeared to be responsible for the radiation sensitivity of those samples. It was concluded that, under certain constrained circumstances, paper and metallic money, personal plastic cards, clothing and shoes could be used as emergency OSL dosimeters in triage applications. - Highlights: • Money, plastic cards, clothing and shoes were studied as emergency OSL dosimeters. • Values of the minimum measurable doses were below 2 Gy for most tested samples. • Tested materials could be used as emergency OSL dosimeters in triage applications

  11. Optical stimulated luminescence (OSL) dating

    International Nuclear Information System (INIS)

    Banerjee, D.

    1999-01-01

    Since the pioneering work by Huntley et al. (1985), optical dating is being increasingly recognised as an important technique for establishing a time frame of deposition of sediments (Aitken, 1998). Optical dating differs from thermoluminescence (TL) dating in that visible/infrared light from lasers or LEDs (light-emitting-diodes) is used as a means of stimulation, in contrast to thermal stimulation. It has several advantages over TL dating: (i) the resetting of the OSL (optically stimulated luminescence) clock is more effective than that of TL clock; for sediments transported under water or in other situations where the sediment grains have undergone inhomogeneous bleaching, this property ensures that ages based on optical dating are generally more reliable than TL ages, (ii) the optical dating technique is non-destructive, and multiple readouts of the optical signal is possible; this feature has resulted in the development of single-aliquot and single-grain protocols (Murray and Wintle, 1999; Banerjee et al. 1999), (iii) the sample is not heated as in TL; thus, spurious luminescence is avoided and there is a significant reduction in blackbody radiation. Dating of materials which change phase on heating is also practical, and finally, (iv) thermal quenching of luminescence is negligible, allowing accurate estimation of kinetic parameters using standard techniques and providing access to deep OSL traps. This characteristic may be helpful in extending the limits of optical dating beyond the last 150 ka from a global point of view

  12. A simple transformation for converting CW-OSL curves to LM-OSL curves

    DEFF Research Database (Denmark)

    Bulur, E.

    2000-01-01

    A simple mathematical transformation is introduced to convert from OSL decay curves obtained in the conventional way to those obtained using a linear modulation technique based on a linear increase of the stimulation light intensity during OSL measurement. The validity of the transformation...... was tested by the IR-stimulated luminescence curves from feldspars, recorded using both the conventional and the linear modulation techniques. The transformation was further applied to green-light-stimulated OSL from K and Na feldspars. (C) 2000 Elsevier Science Ltd. All rights reserved....

  13. Influence of thermal treatment on OSL regeneration in potassium chloride

    International Nuclear Information System (INIS)

    Majgier, Renata; Biernacka, Magdalena; Mandowski, Arkadiusz

    2016-01-01

    Optically stimulated luminescence (OSL) of pure analytical potassium chloride (KCl) prepared in two different forms (crystals and pellets) was studied. The occurrence of regeneration effect (self-renewal of the OSL signal) in the material was examined. The experiments using the variable delay OSL (VD-OSL) method were carried out. Performed measurements allowed to determine time scale of the phenomenon, as well as quantitative changes of regeneration depending on thermal treatment before and after irradiation. Significant increase of the OSL regeneration was noticeable for pellets after the application of the annealing before irradiation, while for crystals a substantial decrease of regeneration was observed. Preheating applied after irradiation caused that self-renewal of OSL signal was drastically reduced or completely suppressed depending on the form of KCl samples. - Highlights: • Optically stimulated luminescence (OSL) of potassium chloride (KCl) was studied. • The measurements were performed using the variable delay OSL method (VD-OSL). • It was found that regeneration of OSL intensity in KCl could be as high as 2000%. • Annealing caused reduction of OSL renewal for crystals and its increase for pellets. • Preheating after irradiation removed or significantly reduced the OSL regeneration.

  14. Natural and laboratory TT-OSL dose response curves: Testing the lifetime of the TT-OSL signal in nature

    International Nuclear Information System (INIS)

    Chapot, M.S.; Roberts, H.M.; Duller, G.A.T.; Lai, Z.P.

    2016-01-01

    This study compares natural and laboratory generated thermally transferred optically stimulated luminescence (TT-OSL) dose response curves (DRCs) for fine-grain quartz extracts from the Luochuan loess section in central China. Both DRCs saturate at high doses relative to the quartz OSL signal; the natural TT-OSL DRC saturates at about 2200 Gy and laboratory DRCs saturate at about 2700 Gy. However, the natural and laboratory TT-OSL DRCs deviate from one another at circa 150 Gy resulting in TT-OSL equivalent dose underestimation relative to palaeodoses expected from dose rates and independent age control. The lifetime of the TT-OSL signal at 10 °C, calculated from values of trap parameters E and s, is compared against the value for lifetime of the TT-OSL signal in nature at average burial temperature as determined from the age underestimation caused by deviation of the natural and laboratory generated DRCs. These two independent assessments of TT-OSL signal lifetime at Luochuan give similar values, suggesting that laboratory measurements of thermal stability reflect natural burial lifetimes and can potentially be used to correct TT-OSL ages for the difference between natural and laboratory dose response curves. - Highlights: • Natural and laboratory TT-OSL DRCs deviate at ∼150 Gy but saturate at higher doses. • TT-OSL signal lifetime at 10 °C calculated from measured E and s values is ∼180 ka. • TT-OSL signal lifetime at Luochuan estimated from the DRCs' deviation is ∼175 ka. • Natural and laboratory TT-OSL DRC deviation may be caused by low thermal stability. • Laboratory measurements of signal lifetime may be able to correct old TT-OSL ages.

  15. Tl and OSL on diopside crystal

    International Nuclear Information System (INIS)

    Cano, N.F.; Watanabe, S.; Mittani, J.C.R.; Yukihara, E.G.

    2006-01-01

    The diopside with chemical composition CaMgSi 2 O 6 is part of an important solid solution series of the pyroxene group. The mineral is commonly found in meteorites and it is an important rock forming mineral of medium and high grade metamorphic rocks which are rich in calcium. In the bibliography it is possible to found several studies on electron spin resonance (ESR), reflectance, etc. but not on thermoluminescence (TL) or optically stimulated luminescence (OSL). In the present work we studied diopside TL and OSL behaviour on natural and natural irradiated samples. The sample used in our study is a white coloured diopside provided by Mineracao Sao Judas located in Sao Paulo, Brazil. The X-Ray Fluorescence technique has shown high concentrations of SiO 2 (55.81 % mol), CaO (23.47 % mol), MgO (18.03 % mol), Al 2 O 3 (1.56 % mol), Fe 2 O 3 (0.53 % mol), K 2 O (0.44 % mol), TiO 2 (0.065 % mol), P 2 O 5 (0.026 % mol), and MnO (0.013 % mol). TL measurements on natural samples show four TL peaks at 160, 260, 360, and 450 C. After beta-irradiation an increment mainly in the low temperature peaks is observed. As for OSL measurements, low OSL signal was observed on natural samples using blue light stimulation and UV detection. The intensity of the signal was observed to increase with the irradiation dose. (Author)

  16. The TL and OSL study of hydroxyapatites for dosimetric applications

    International Nuclear Information System (INIS)

    Alencar, Marcus A. Vallim de

    2009-01-01

    The hydroxyapatite, the principal mineral component of the bone and tooth enamel, is one of the dosimetric materials that has distinguished itself in the high dose and accidents dosimetry, as well as in the dating, for the Electron Paramagnetic Resonance (EPR) technique. For this reason, the hydroxyapatite could also be used as Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) dosimeter in the dosimetry of high doses and accidents, and also in the archaeological and geological dating. This work presents a brief study of the TL and OSL behaviour of the B type synthetic carbonated hydroxyapatite, observing the possibility to use this material in TL and OSL dosimetry. The samples were irradiated to a dose of 100 Gy and 1000 Gy, and the TL and OSL measurements were obtained by the RISOE TL/OSL reader, model TL/OSL-DA-15B. The first results demonstrate the presence of three peaks in the TL glow curve in the temperatures of 100 deg C, 150 deg C and 280 deg C. The synthetic carbonated hydroxyapatite also presents an OSL signal when the sample is stimulated with blue light and a small OSL signal for stimulation with infrared light (IR). These results indicate the possibility of this synthetic carbonated hydroxyapatite to be used as dose indicator material using the TL and OSL techniques. (author)

  17. Utilisation of OSL from table salt in retrospective dosimetry

    International Nuclear Information System (INIS)

    Fujita, Hiroki; Jain, Mayank; Murray, Andrew S.

    2011-01-01

    Common salt (NaCl) has previously been suggested for use in dose estimation in accident dosimetry. In this study, we investigated the optically stimulated luminescence (OSL) and violet thermoluminescence (VTL) characteristics of 'Aji-Shio' (Ajinomoto), a Japanese commercial salt. A comparison of OSL and TL signals allowed identification of common source traps. The initial OSL signal contained a dominant thermally unstable component, which necessitated prior heat treatment. Based on these luminescence characteristics, a single-aliquot regenerative-dose (SAR) OSL protocol was modified and tested. The protocol worked very well for six types of salt, but not for four other types of salt. A minimum detection limit of ∼15 mGy was estimated using the OSL protocol; this is lower than the value obtained from other forms of OSL retrospective dosimetry and lower than that obtained using electron spin resonance (ESR) dosimetry. It was concluded that the OSL from Japanese commercial salt could be used successfully to derive precise estimates of accident dose. (author)

  18. Application of pulsed OSL to polymineral fine-grained samples

    International Nuclear Information System (INIS)

    Feathers, James K.; Casson, M. Aksel; Schmidt, Amanda Henck; Chithambo, Makaiko L.

    2012-01-01

    Pulsed OSL is applied to nine fine-grained sediment samples from Sichuan province, China, using stimulating pulses of 10 μs on and 240 μs off, with an infrared exposure prior to each OSL measurement. Comparison of fading rates between pulsed and non-pulsed signals, the latter also obtained with a preceding IR exposure, shows that fading is significant for mainly the non-pulsed signals. Presence of a pulsed IRSL and the magnitudes of b-value to correct for lower alpha efficiency suggest that pulsing does not fully remove a significant feldspar signal, only a fading component. Comparison with ages of quartz extracts shows that pulsed OSL ages are consistent, while CW-OSL ages are slightly older and CW-IRSL ages are much older. The older ages suggest a less well-bleached feldspar component.

  19. OSL-thermochronometry using bedrock quartz: a note of caution

    DEFF Research Database (Denmark)

    Guralnik, B.; Ankjærgaard, Christina; Jain, Mayank

    2015-01-01

    Optically stimulated luminescence (OSL) thermochronometry is an emerging application, whose capability to record sub-Million-year thermal histories is of increasing interest to a growing number of subdisciplines of Quaternary research. However, several recent studies have encountered difficulties......, and may hamper successful OSL dating. Furthermore, even when the desirable signal is present, its concentration might be indistinguishable from its environmental steady-state prediction, thus preventing its conversion to a cooling or heating history. We explore the saturation properties and the thermal...

  20. Alpha efficiency under TL and OSL - A subtraction technique using OSL and TL to detect artificial irradiation

    International Nuclear Information System (INIS)

    Zink, A.J.C.; Dabis, S.; Porto, E.; Castaing, J.

    2010-01-01

    With the development of thermoluminescence (TL) and optically stimulated luminescence (OSL) to determine the authenticity of old ceramics, forgers use artificial irradiation by gamma ray to age modern productions. Besides fraudulent action, objects can be exposed to various sources of X-rays (e.g. radiography, security control at airports). For all these reasons, the determination of artificial irradiation is an important topic for dating art objects. The main technique to identify artificial irradiations is the subtraction technique. It is based on the fact that alpha efficiency varies according to the luminescence technique (fine grain, coarse grains, predose, OSL). Having observed a rather significant difference of alpha efficiency for TL and OSL, we propose a new subtraction technique using OSL and TL of fine grains.

  1. Developing a SAR TT-OSL protocol for volcanically-heated aeolian quartz from Datong (China)

    DEFF Research Database (Denmark)

    Liu, Jinfeng; Murray, Andrew S.; Jain, Mayank

    2012-01-01

    The thermally-transferred optically stimulated luminescence (TT-OSL) responses of chemically-purified fine-grained quartz from a lava-baked aeolian sediment from Datong (China) are presented. Our main focus is to examine the suitability of the test dose TT-OSL and OSL response to monitor sensitiv......The thermally-transferred optically stimulated luminescence (TT-OSL) responses of chemically-purified fine-grained quartz from a lava-baked aeolian sediment from Datong (China) are presented. Our main focus is to examine the suitability of the test dose TT-OSL and OSL response to monitor...

  2. A reusable OSL-film for 2D radiotherapy dosimetry

    Science.gov (United States)

    Wouter, Crijns; Dirk, Vandenbroucke; Paul, Leblans; Tom, Depuydt

    2017-11-01

    Optical stimulated luminescence (OSL) combines reusability, sub-mm resolution, and a linear dose response in a single radiation detection technology. Such a combination is currently lacking in radiotherapy dosimetry. But OSL-films have a strong energy dependent response to keV photons due to a relative high effective atomic number (Z eff). The current work studied the applicability of a 2D OSL-film with a reduced Z eff as (IMRT/VMAT) dosimeter. Based on their commercial OSL-film experience, Agfa Healthcare N.V. produced a new experimental OSL-film for RT dosimetry. This film had a lower effective atomic number compared to the films used in radiology. Typical 2D dosimeter requirements such as uniformity, dose response, signal stability with time, and angular dependence were evaluated. Additionally, the impact of a possible residual energy dependence was assessed for the infield as well as the out-of-field region of both static beams and standard intensity modulated patterns (chair and pyramid). The OSL-film’s reusable nature allowed for a film specific absolute and linear calibration including a flood-field uniformity correction. The OSL-film was scanned with a CR-15X engine based reader using a strict timing (i.e. 4 min after ‘beam on’ or as soon as possible) to account for spontaneous recombination. The OSL-film had good basic response properties: non-uniformities  ⩽2.6%, a linear dose response (0-32 Gy), a linear signal decay (0.5% min-1) over the 20 min measured, and limited angular dependence  ⩽2.6%. Due to variations of the energy spectrum, larger dose differences were noted outside the central region of the homogenous phantom and outside both static and IMRT fields. However, the OSL-film’s measured dose differences of the IMRT patterns were lower than those of Gafchromic EBT measurements ([-1.6%, 2.1%] versus [-2.9%, 3.6%]). The current OSL-film could be used as a reusable high resolution dosimeter with read-out immediately after

  3. Emergency EPR and OSL dosimetry with table vitamins and minerals.

    Science.gov (United States)

    Sholom, S; McKeever, S W S

    2016-12-01

    Several table vitamins, minerals and L-lysine amino acid have been preliminarily tested as potential emergency dosemeters using electron paramagnetic resonance (EPR) and optically stimulated luminescence (OSL) techniques. Radiation-induced EPR signals were detected in samples of vitamin B2 and L-lysine while samples of multivitamins of different brands as well as mineral Mg demonstrated prominent OSL signals after exposure to ionizing radiation doses. Basic dosimetric properties of the radiation-sensitive substances were studied, namely dose response, fading of the EPR or OSL signals and values of minimum measurable doses (MMDs). For EPR-sensitive samples, the EPR signal is converted into units of dose using a linear dose response and correcting for fading using the measured fading dependence. For OSL-sensitive materials, a multi-aliquot, enhanced-temperature protocol was developed to avoid the problem of sample sensitization and to minimize the influence of signal fading. The sample dose in this case is also evaluated using the dose response and fading curves. MMDs of the EPR-sensitive samples were below 2 Gy while those of the OSL-sensitive materials were below 500 mGy as long as the samples are analyzed within 1 week after exposure. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Desiccants for retrospective dosimetry using optically stimulated luminescence (OSL)

    International Nuclear Information System (INIS)

    Geber-Bergstrand, Therése; Bernhardsson, Christian; Christiansson, Maria; Mattsson, Sören; Rääf, Christopher L.

    2015-01-01

    Optically stimulated luminescence (OSL) was used to test different kinds of desiccants for their potential use in retrospective dosimetry. Desiccants are used for the purpose of absorbing liquids and can be found in a number of items which may be found in the immediate environment of a person, including hand bags, drug packages, and the vehicles of rescue service teams. Any material exhibiting OSL properties suitable for retrospective dosimetry is a useful addition to the existing dosimetry system available in emergency preparedness. Eleven kinds of desiccants were investigated in order to obtain an overview of the fundamental OSL properties necessary for retrospective dosimetry. Measurements were made using a Risø TL/OSL reader and irradiations were achieved with the 90 Sr/ 90 Y source incorporated in the reader. Several of the desiccants exhibited promising properties as retrospective dosemeters. Some of the materials exhibited a strong as-received signal, i.e. without any laboratory irradiation, but the origin of this signal has not yet been established. The minimum detectable dose ranged from 8 to 450 mGy for ten of the materials and for one material (consisting of natural clay) the minimum detectable dose was 1.8 Gy. - Highlights: • Desiccants can be used as fortuitous dosemeters using OSL. • The minimum detectable dose for processed desiccants range from 8 to 450 mGy. • The minimum detectable dose for natural clay was 1.8 Gy

  5. Using OSL dating to quantify rates of Earth surface processes

    Science.gov (United States)

    Rhodes, E. J.; Rittenour, T. M.

    2010-12-01

    In Optically Stimulated Luminescence (OSL), the dating signal is reset when mineral grains are exposed to light or heat, and gradually rebuilds during subsequent burial by interaction with ionising radiation. Quartz and feldspar provide useful OSL signals demonstrating rapid signal reduction in only seconds of light exposure. Age estimates ranging from under 1 year to around 200,000 years can be determined for a wide range of sedimentary contexts, including dunes, marine deposits, fluvial and glacial environments, and recent developments provide the framework for low temperature thermochronometric applications on timescales comparable with rapid climate fluctuations. In this presentation, we explore the range of applications for determining rates of Earth surface processes using OSL. We examine technical limitations, and provide a framework for overcoming current difficulties experienced in several specific regions and contexts. We will focus on OSL dating applications to glacigenic and fluvial records, along with use of the technique in tectonic and paleoseismic contexts. In many ways, these represent the most challenging environments for OSL; rapid high energy deposition is associated with incomplete signal zeroing, and the characteristics of quartz in many of these environments make it difficult to derive precise age estimates using this mineral. We will introduce innovative methods to overcome these limitations, both existing and those under development.

  6. Remote TL and OSL for asteroid and meteorite study

    International Nuclear Information System (INIS)

    Takaki, Shunji; Ikeya, Motoji; Yamanaka, Chihiro

    1997-01-01

    Thermoluminescence (TL) and optically stimulated luminescence (OSL) of the Allende meteorite have been studied using infrared CO 2 laser light as a heat source and He-Ne laser light to excite the material, respectively from a long distance. New techniques of remote TL (R-TL) and remote OSL (R-OSL) have been developed for future remote dating from a long distance in a planetary survey. The upper limits of the distance for R-TL and R-OSL were estimated using the laboratory TL signal of the meteorite peaking at 320 o C: about 400 photons s -1 for the R-TL and 60 photons s -1 for R-OSL at a distance of 1 km using a laser beam with the divergence of 0.1 mrad at powers of 100 and 1 W, respectively. An age limit of 10 5 or 10 6 years due to the signal saturation and the objects heterogeneity, as expected from previous studies, may make the asteroid survey difficult but would still help to investigate the surface activities of icy planets and satellites in outer planet worlds. (author)

  7. Properties of lithium aluminate for application as an OSL dosimeter

    International Nuclear Information System (INIS)

    Twardak, A.; Bilski, P.; Marczewska, B.; Lee, J.I.; Kim, J.L.; Gieszczyk, W.; Mrozik, A.; Sądel, M.; Wróbel, D.

    2014-01-01

    Several samples of undoped and carbon or copper doped lithium aluminate (LiAlO 2 ) were prepared in an attempt to achieve a material, which can be applicable in optically stimulated luminescence (OSL) dosimetry. All investigated samples are highly sensitive to ionizing radiation and show good reproducibility. The undoped and copper doped samples exhibit sensitivity several times higher than that of Al 2 O 3 :C, while sensitivity of the carbon doped samples is lower. The studied samples exhibit significant fading, but dynamics of signal loss is different for differently doped samples, what indicates a possibility of improving this characteristic by optimizing dopant composition. - Highlights: • OSL properties of lithium aluminate for personal dosimetry. • Doping influence on OSL fading of lithium aluminate. • Application of lithium aluminate in thermal neutron measurements

  8. Firing temperature of pottery using TL and OSL techniques

    International Nuclear Information System (INIS)

    Polymeris, G.S.; Sakalis, A.; Papadopoulou, D.; Dallas, G.; Kitis, G.; Tsirliganis, N.C.

    2007-01-01

    Several methods of thermal analysis are used to determine in the laboratory the firing temperature of ancient ceramic sherds. These methods are based primarily on changes of physical characteristics occurring when clay minerals are heated. The luminescence properties of quartz grains in a ceramic matrix also undergo certain changes during firing. The possibility of measuring the sensitivity change (sensitization) of quartz in order to determine the firing temperature of archeological ceramic artifacts was investigated. The sensitivity change was studied for both the thermoluminescence (TL) and the optically stimulated luminescence (OSL) signal for a ceramic sample of known firing temperature. Various segments of the sample were annealed to a different temperature. Subsequently, the initial sensitivity, as well as the thermal and the pre-dose sensitization were measured for both TL and OSL at room temperature as a function of the annealing temperature. The obtained TL glow curves showed different shapes for annealing temperatures above the firing temperature. Thermal and pre-dose sensitizations also exhibited a similar, although less prominent, rise. The OSL signal was analyzed by integrating the raw signal over the initial second of stimulation. The initial sensitivity showed an abrupt change for annealing temperatures around the firing temperature. An alternative approach used for the analysis of the OSL signal involved a full-component resolved sensitization study. The same abrupt change for the initial sensitivity of both the first and second components was observed, as well as, a clear but not very prominent thermal sensitization trend for annealing temperatures above the firing temperature

  9. Temperature dependence of OSL decay curves: Experimental and theoretical aspects

    DEFF Research Database (Denmark)

    McKeever, S.W.S.; Bøtter-Jensen, L.; Agersnap Larsen, N.

    1997-01-01

    ; (2) thermally assisted optical stimulation; (3) thermal quenching; and (4) localized donor-acceptor type recombination. Experimental OSL data from natural quartz and feldspars, stimulated with both green and infra-red light, are examined in the light of the theoretical considerations. (C) 1997...

  10. Does deposition depth control the OSL bleaching of fluvial sediment?

    NARCIS (Netherlands)

    Cunningham, A. C.; Wallinga, J.; Hobo, N.; Versendaal, A. J.; Makaske, B.; Middelkoop, H.

    2014-01-01

    The Optically Stimulated Luminescence (OSL) signal from fluvial sediment often contains a remnant from the previous deposition cycle, leading to a partially bleached equivalent-dose distribution. Although identification of the burial dose is of primary concern, the degree of bleaching could

  11. OSL at elevated temperatures: Towards the simultaneous thermal and optical stimulation

    International Nuclear Information System (INIS)

    Polymeris, George S.

    2015-01-01

    In routine OSL dating measurements, a preheat procedure at high temperatures is used to empty the shallow traps. Thus no contribution from shallow traps was expected as each OSL measurement is subsequently performed at moderately high temperatures, around 110–125 °C. The present work attempts to consider the OSL measurements performed at elevated temperatures without any previous preheat as a case of simultaneous thermal and optical stimulation of the same trap. Towards this direction, a set of proposed equations is derived for all three different cases of optical stimulation modes, namely CW-OSL, LM-OSL as well as PS-LM-OSL. According to these equations, indicative features of thermally activated OSL processes are expected, such as the steepening of CW-OSL decay curves as either stimulation temperature or intensity increases, as well as the shifting of the stimulation time of the maximum intensity for both LM-OSL and PS-LM-OSL curves towards shorter times with increasing temperatures. Experimentally, specific measurement sequences after varying stimulation temperature and/or intensity were applied in order to estimate the values of associated trap parameters, such as activation energy and photo-ionization cross-section. Experimental OSL data from a milky natural quartz sample stand in good agreement of these theoretical considerations in the case of 110 °C TL peak and the intense OSL component C 2 monitored at RT. - Highlights: • OSL at elevated temperatures without preheat results from two simultaneous stimulation modes. • Equations were derived assuming of linear superposition of two stimulation modes. • Data for 110 °C TL peak and OSL C 2 at RT stand in agreement with these equations. • Results verify the linear superposition of the two stimulation modes

  12. Performance of OSL dosimeters in clinical beams from mammography; Desempenho de dosimetros OSL em feixes clinicos empregados na mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Caio V.; Cabete, Henrique V.; Alves, Fatima F.R.; Pires, Silvio R.; Medeiros, Regina B.; Freitas, Marcelo B. [Universidade Federal de Sao Paulo (HSP/EPM/UNIFESP), SP (Brazil). Escola Paulista de Medicina; Malthez, Anna Luiza M.C. [Universidade Estadual de Campinas (CPG/FEEC/UNICAMP), Campinas, SP (Brazil). Faculdade de Engenharia Eletrica e de Computacao. Programa de Pos-Graduacao

    2015-08-15

    The search for the relationship between dose and mammography image is critical to the quality of clinical practice. In this sense, dosimetry using optically stimulated luminescent detectors (OSLD) is configured as alternative to traditional methods and allows on-site dose checks received by patients. This study aimed to verify the performance of OSL dosimeters in clinical beams typically used in mammography. For this, aluminum oxide detectors, especially designed to reduce interference on the image quality, were exposed to radiation beam combining targets and filters of a mammography equipment with digital imaging system. In addition were also employed lithium fluoride detectors irradiated under the same conditions, together with a ionization chamber for determination of dose values. A homogeneous acrylic phantom was designed and used for simulating different breast and also determine internal dose values under the irradiation conditions. The results allowed the determination of calibration factors (OSL signal x dose) of the exposed detectors to the radiation beams typically used in clinical practice. The phantom images and the comparison between TL and OSL responses suggest the possibility of routine use of the OSL dosimetry system in mammography. (author)

  13. Component resolved bleaching study in natural calcium fluoride using CW-OSL, LM-OSL and residual TL glow curves after bleaching

    International Nuclear Information System (INIS)

    Angeli, Vasiliki; Polymeris, George S.; Sfampa, Ioanna K.; Tsirliganis, Nestor C.; Kitis, George

    2017-01-01

    Natural calcium fluoride has been commonly used as thermoluminescence (TL) dosimeter due to its high luminescence intensity. The aim of this work includes attempting a correlation between specific TL glow curves after bleaching and components of linearly modulated optically stimulated luminescence (LM-OSL) as well as continuous wave OSL (CW-OSL). A component resolved analysis was applied to both integrated intensity of the RTL glow curves and all OSL decay curves, by using a Computerized Glow-Curve De-convolution (CGCD) procedure. All CW-OSL and LM-OSL components are correlated to the decay components of the integrated RTL signal, apart from two RTL components which cannot be directly correlated with either LM-OSL or CW-OSL component. The unique, stringent criterion for this correlation deals with the value of the decay constant λ of each bleaching component. There is only one, unique bleaching component present in all three luminescence entities which were the subject of the present study, indicating that each TL trap yields at least three different bleaching components; different TL traps can indicate bleaching components with similar values. According to the data of the present work each RTL bleaching component receives electrons from at least two peaks. The results of the present study strongly suggest that the traps that contribute to TL and OSL are the same. - Highlights: • A component resolved bleaching study was attempted to CaF_2:N in terms of CW-OSL, LM-OSL and RTL. • Bleaching decay constants originating from different TL peaks yield overlapping values. • Three to five individual components were used in order to describe the bleaching behavior in all luminescence entities. • There is only one, unique bleaching component present in all three luminescence entities.

  14. Influence of pre-measurement thermal treatment on OSL of synthetic quartz measured at room temperature

    International Nuclear Information System (INIS)

    Kale, Y.D.; Gandhi, Y.H.

    2008-01-01

    Much effort has been made to study the influence of pre-measurement thermal treatment and ionizing radiation on quartz specimens owing to its use in a large number of applications. Optically stimulated luminescence (OSL) being a structured and sensitive phenomenon promises to correlate the responsible color center and luminescence emission. OSL studies on quartz with such conditions can reveal many significant results. The aim of the present investigation is to understand the effect of annealing temperature on OSL characteristics of synthetic quartz recorded at room temperature. At identical annealing duration and β-dose, the shape of OSL decay curve remains non-exponential; when specimens annealed at lower temperature (∼400 deg. C). The shape of decay curve changes to exponential in nature along with rise in OSL intensity when the specimen was given higher temperature of annealing (>400 deg. C). The effects of such protocol on pattern of OSL sensitivity as well as area under the OSL decay curve are also presented here. The presence of shallow traps, when OSL decay curve was recorded at room temperature seems to be responsible for the changes in OSL pattern. The influence of shallow traps is attributed to non-exponential decay of OSL recorded at room temperature

  15. Angular dependence of the nanoDot OSL dosimeter

    OpenAIRE

    Kerns, James R.; Kry, Stephen F.; Sahoo, Narayan; Followill, David S.; Ibbott, Geoffrey S.

    2011-01-01

    Purpose: Optically stimulated luminescent detectors (OSLDs) are quickly gaining popularity as passive dosimeters, with applications in medicine for linac output calibration verification, brachytherapy source verification, treatment plan quality assurance, and clinical dose measurements. With such wide applications, these dosimeters must be characterized for numerous factors affecting their response. The most abundant commercial OSLD is the InLight∕OSL system from Landauer, Inc. The purpose of...

  16. Study of the OSL response of the CaF2:Dy (TLD-200) dosimeter

    International Nuclear Information System (INIS)

    Medeiros, Beatriz M.; Alencar, Marcus A.V. de

    2013-01-01

    The OSL dosimetry has become, in recent years, a successful technique in personal and environmental dosimetry due to high luminescence efficiency, excellent reproducibility, fast readout of signal and repeated and successive OSL measurements of the same dosimeter. Another factor that contributes to the increased use of OSL dosimetry is the use of the aluminum oxide doped with carbon (Al 2 O 3 :C) as dosimeter. Developed initially as thermoluminescent dosimeter, the Al 2 O 3 :C has an excellent OSL sensitivity, high efficiency, good linearity, low or no fading and excellent stability with respect to environmental conditions. However, the OSL dose response for aluminum oxide is linear only for low doses. For intermediate doses (doses in radiotherapy), the response is supralinear. For the values of high doses used in the processes of food irradiation and sterilization of surgical materials, the OSL signal of the aluminum oxide already saturated. Furthermore, the degree of supralinearity and the saturation value vary from sample to sample (∼ 30-300 Gy). Therefore, the use of aluminum oxide as OSL dosimeter is inappropriate in radiotherapy and in the irradiation industrial processes. The objective of this work is the study of the OSL properties of other dosimetric materials irradiated with values of intermediate and high dose to verify the applicability of the OSL dosimetry in radiotherapy and in the processes of food irradiation and sterilization of medical materials. The dosimetric material used in this work is the calcium fluoride doped with dysprosium (CaF 2 :Dy) produced by Harshaw and known commercially as TLD-200. The results demonstrate that the CaF 2 :Dy has OSL signal and the OSL dose response is linear in the range of 10 Gy to 300 Gy. Therefore, the dosimetry OSL with this dosimeter can be used in the evaluation of doses of the order of dozens to hundreds of grays. (author)

  17. The origin of the medium OSL component in West Australian quartz

    International Nuclear Information System (INIS)

    Wang, X.L.; Du, J.H.; Adamiec, G.; Wintle, A.G.

    2015-01-01

    Optically stimulated luminescence (OSL) of a coarse-grained sedimentary quartz from West Australia was investigated. Observations of OSL and TL (thermoluminescence) were made following a series of experiments using different heating and optical bleaching conditions, and with optical stimulation at several different temperatures. Analysis of the fast and medium OSL components suggests that the medium OSL component observed after heating at 260 °C is a by-product of the production of the fast component, and both of them have as their original source the 325 °C TL trap. During fast OSL production following irradiation and preheating, some of the electrons evicted into the conduction band are re-trapped in an intermediate trap corresponding to the 170 °C TL peak; from here they are instantaneously stimulated to give rise to the medium OSL signal when the blue light stimulation is switched on, and subsequently result in the residual recuperated TL after the blue light is switched off. The kinetic properties of the medium OSL component are determined by the properties of both the 170 °C and 325 °C TL traps in contrast to the conventional interpretation of the medium component being derived from an independent source trap. Therefore, the 170 °C TL trap also plays unexpected roles in quartz OSL production with elevated stimulation temperatures (e.g. 125 °C or 130 °C, currently used for OSL dating), while the 110 °C TL trap and its influences are being avoided. - Highlights: • Quartz medium OSL component is a by-product of fast OSL component production. • Medium component is mediated by the 170 C TL peak. • Phototransfer is responsible for the medium OSL

  18. Modelling the thermal bleaching of OSL signal in the case of a competition between recombination centres

    International Nuclear Information System (INIS)

    Chruscinska, A.

    2009-01-01

    The thermal bleaching of the optically stimulated luminescence (OSL) has been investigated by computer simulations for a model including three traps and two luminescence centres. The deepest trap is active only during the OSL process. Two other traps are active only during the thermal bleaching. The thermal bleaching effects on the OSL intensity as well as on the OSL curve shape are presented for the wide range of trap and luminescence centre parameters and for the different settings of optical detection window. The conventional OSL curve analysis consisting in decomposition of the OSL curve into first order components is applied to the simulation results and the optical cross section spectra obtained as a result of this analysis are compared with the model assumptions. The simulations show that OSL signal can decrease to undetectable level even when the traps related to this signal are not emptied during thermal bleaching. The residual level of the OSL signal after bleaching process, however, depends strongly on centre parameters and concentrations. The modifications of optical detection spectral window lead to significant changes of bleaching effects. The thermal bleaching influences also the optical cross section spectra obtained as a result of the OSL curve decomposition.

  19. Gamma response characterizations of optically stimulated luminescence (OSL) affects personal dosimetry

    Science.gov (United States)

    Monthonwattana, S.; Esor, J.; Rungseesumran, T.; Intang, A.

    2017-06-01

    Optically Stimulated Luminescence (OSL) is the current technique of personal dosimetry changed by Nuclear Technology Service Center instead of Thermoluminescence dosimetry (TLD) because OSL has more advantages, such as repeat reading and elimination of heating process. In this study, OSL was used to test the gamma response characterizations. Detailed OSL investigation on personal dosimetry was carried out in the dose range of 0.2 - 3.0 mSv. The batch homogeneity was 7.66%. R2 value of the linear regression was 0.9997. The difference ratio of angular dependence at ± 60° was 8.7%. Fading of the reading was about 3%.

  20. Clinical characterization of OSL dosimeters for use in dosimetry of teletherapy beams in conventional fractionation; Caracterizacion clinica de dosimetros OSL para su uso en dosimetria de haces de teleterapia en fraccionamiento convencional

    Energy Technology Data Exchange (ETDEWEB)

    Lopez V, A.; Gutierrez M, J. G.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Velazquez T, J. J., E-mail: jggm25@yahoo.com.mx [Centro Medico Nacional Siglo XXI, Hospital de Oncologia, Departamento de Fisica Medica, Av. Cuauhtemoc No. 330, Col. Doctores, 06720 Mexico D. F. (Mexico)

    2015-10-15

    Optically stimulated materials are increasingly used for dosimetry in clinical settings; to be sure of the obtained reading their proper clinical characterization is necessary. Is important to know the homogeneity of a batch, reproducibility, be exposed to the same conditions of irradiation repeatedly and other dependences that could present such as energy, angular, the type of radiation which are exposed and the dose deposited in them. For characterization they were designed and implemented tests for each of the factors of interest, taking into account the need for them (calculations, manufacture of mannequins, conditions, practicality, etc.) It was shown that we can apply this dosimetry in clinical practice within a radiotherapy center, relying on the readings and practicality. (Author)

  1. Optically stimulated luminescence (OSL) of dental enamel for retrospective assessment of radiation exposure

    International Nuclear Information System (INIS)

    Yukihara, E.G.; Mittani, J.; McKeever, S.W.S.; Simon, S.L.

    2007-01-01

    This paper briefly reviews the optically stimulated luminescence (OSL) properties of dental enamel and discusses the potential and challenges of OSL for filling the technology gap in biodosimetry required for medical triage following a radiological/nuclear accident or terrorist event. The OSL technique uses light to stimulate a radiation-induced luminescence signal from materials previously exposed to ionizing radiation. This luminescence originates from radiation-induced defects in insulating crystals and is proportional to the absorbed dose of ionizing radiation. In our research conducted to date, we focused on fundamental investigations of the OSL properties of dental enamel using extracted teeth and tabletop OSL readers. The objective was to obtain information to support the development of the necessary instrumentation for retrospective dosimetry using dental enamel in laboratory, or for in situ and non-invasive accident dosimetry using dental enamel in emergency triage. An OSL signal from human dental enamel was detected using blue, green, or IR stimulation. Blue/green stimulation associated with UV emission detection seems to be the most appropriate combination in the sense that there is no signal from un-irradiated samples and the shape of the OSL decay is clear. Improvements in the minimum detection level were achieved by incorporating an ellipsoidal mirror in the OSL system to maximize light collection. Other possibilities to improve the sensitivity and research steps necessary to establish the feasibility of the technique for retrospective assessment of radiation exposure are also discussed

  2. On the OSL curve shape and preheat treatment of electronic components from portable electronic devices

    DEFF Research Database (Denmark)

    Woda, Clemens; Greilich, Steffen; Beerten, Koen

    2010-01-01

    The shape of the OSL decay curve and the effect of longer time delays between accidental exposure and readout of alumina-rich electronic components from portable electronic devices are investigated. The OSL decay curve follows a hyperbolic decay function, which is interpreted as an approximation ...

  3. OSL sensitivity changes during single aliquot procedures: Computer simulations

    DEFF Research Database (Denmark)

    McKeever, S.W.S.; Agersnap Larsen, N.; Bøtter-Jensen, L.

    1997-01-01

    We present computer simulations of sensitivity changes obtained during single aliquot, regeneration procedures. The simulations indicate that the sensitivity changes are the combined result of shallow trap and deep trap effects. Four separate processes have been identified. Although procedures can...... be suggested to eliminate the shallow trap effects, it appears that the deep trap effects cannot be removed. The character of the sensitivity changes which result from these effects is seen to be dependent upon several external parameters, including the extent of bleaching of the OSL signal, the laboratory...

  4. Assessing the completeness of optical resetting of quartz OSL in the natural environment

    International Nuclear Information System (INIS)

    Singarayer, J.S.; Bailey, R.M.; Ward, S.; Stokes, S.

    2005-01-01

    Resetting of previously accumulated optically stimulated luminescence (OSL) signals during transport of sediment is a fundamental requirement for reliable optical dating. The completeness of optical resetting of 46 modern-age quartz samples from a variety of depositional environments was examined. All equivalent dose (D e ) estimates were e from easy-to-bleach through to hard-to-bleach components. For all modern fluvial samples with non-zero D e values, SAR D e (t) analysis and component-resolved linearly modulated OSL (LM OSL) D e estimates showed this to be the case, implying incomplete resetting of previously accumulated charge. LM OSL measurements were also made to investigate the extent of bleaching of the slow components in the natural environment. In aeolian sediments examined, the natural LM OSL was effectively zero (i.e. all components were fully reset). The slow components of modern fluvial samples displayed measurable residual signals up to 15Gy

  5. Constraining the timing of palaeosol development in Iranian arid environments using OSL dating

    DEFF Research Database (Denmark)

    Rashidi, Zakieh; Sohbati, Reza; Karimi, Alireza

    2018-01-01

    are compared to investigate the degree of bleaching of quartz OSL in individual samples at the time of deposition. A comparison between the quartz OSL and K-feldspar IR50 ages shows that 12 out of 15 samples were probably well-bleached prior to deposition. The 17 OSL ages constrain at least four broad phases......The ages of palaeosols in arid environments in Iran are constrained using the optically stimulated luminescence (OSL) signal from quartz. The luminescence properties of quartz OSL and K-feldspar infrared stimulated luminescence (IRSL) at 50 °C (IR50) and post-IR IRSL at 290 °C (pIRIR290) signals...

  6. Natural and laboratory OSL growth curve–Verification of the basic assumption of luminescence dating

    International Nuclear Information System (INIS)

    Kijek, N.; Chruścińska, A.

    2016-01-01

    The basic assumption of luminescence dating is the equality between the growth curve of OSL generated by the natural radiation and the OSL growth curve reconstructed in laboratory conditions. The dose rates that generate the OSL in nature and in laboratory experiments differ by about ten orders of magnitude. Recently some discrepancies between the natural and laboratory growth curves have been observed. It is important to establish their reasons in order to introduce appropriate correction into the OSL dating protocol or to find a test that allows to eliminate the samples which should not be used for dating. For this purpose, both growth curves, natural and laboratory, were reconstructed by means of computer simulations of the processes occurring in the sample during its deposition time in environment as well as those which occur in a laboratory during dating procedure. The simulations were carried out for three models including one shallow trap, two OSL traps, one disconnected deep and one luminescence center. The OSL model for quartz can be more complex than the one used in the presented simulations, but in spite of that the results show effects of growth curves discrepancies similar to those observed in experiments. It is clear that the consistency of growth curves is not a general feature of the OSL processes, but rather a result of an advantageous configuration of trap parameters. The deep disconnected traps play the key role and their complete filling before the zeroing of OSL signal is a necessary condition of the growth curves' consistency. - Highlights: • Process of OSL growth curve generation in nature and in laboratory was simulated. • Discrepancies between the natural and the laboratory growth curves are observed. • Deep disconnected traps play the key role in growth curve inequality. • Empty deep traps before zeroing of OSL cause the inequality of growth curves.

  7. Analysis of optical bleaching of OSL signal in sediment quartz

    International Nuclear Information System (INIS)

    Przegiętka, K.R.; Chruścińska, A.

    2013-01-01

    The aim of this work was to study the effect of the quality of optical bleaching on the results of OSL (Optically Stimulated Luminescence) dating method. The large aliquots of coarse quartz grains extracted from fluvial deposit were used in the study. The poor, medium and good bleaching were simulated in laboratory with help of Blue LED light source in series of experiments. Then the samples were irradiated with a common laboratory dose. The equivalent doses (DE) were measured by the help of standard Single Aliquot Regeneration (SAR) technique, but obtained DE distributions are analyzed in a new way. The method for recognizing and compensating for partial bleaching is proposed. The conclusions for dating sediment quartz samples are presented and discussed. -- Highlights: ► Bleaching experiments on sediment quartz are performed. ► Blue LED light source incorporated in luminescence reader is used. ► New analysis of data measured by standard SAR OSL technique is proposed. ► The results are promising for recognizing and compensating for partial bleaching

  8. Improvement of the M/S manipulator maintenance at OSL

    International Nuclear Information System (INIS)

    Kuwana, Koichi; Ouchi, Hiroshi; Ito, Yutaka; Sato, Yoshihiro; Midorikawa, Mituhiro; Hayakawa, Tuyoshi

    2010-01-01

    The safeguards inspection samples from the JNFL Rokkasho Reprocessing Plant (RRP) are received and analyzed at the On Site Laboratory (OSL). Since the samples from the input accountancy tank of the RRP contain a lot of fission products, they are treated in a hot-cell line with a M/S (Master /Slave) manipulator. Special equipment and tools were used for the maintenance of the M/S manipulator, especially for the exchange of the M/S manipulator. However, the manipulator exchange work was not easy due to the limitation of the space in the OSL. For solution to this problem, a monorail and monorail hoist equipment was installed onto wall surface of analytical room close to each M/S manipulator, and then it made the exchange of M/S manipulator easy without special equipment and tools. Additionally, operator was freed from the burden of working space arranging for the exchange of M/S manipulator such as removing of analytical equipments. This report represents the improvement of operation for the exchange of M/S manipulator with installation of monorail and hoist equipment. (author)

  9. An environmental BeO-OSL dosimeter for emergency response

    International Nuclear Information System (INIS)

    Woda, Clemens; Kaiser, Jan Christian; Urso, Laura; Greiter, Matthias

    2012-01-01

    A conceptual design is presented to use measurements of localized absorbed dose in inner cities for production of high resolution maps of the radioactive contamination following a nuclear emergency or radiological attack. The doses are derived from luminescent detectors pre-fixed at places of high importance (e.g. public squares). For such an environmental dosimeter, BeO is used, which can be read out using optically stimulated luminescence (OSL). A suitable casing of black Perspex has been developed to give a sufficiently accurate estimate of the air kerma value at the detector position. The dosimeter is characterized according to light tightness, dose response and angular photon energy dependence. A short overview of the approach for map production is also given. - Highlights: ► An inexpensive, environmentally stable BeO based OSL dosimeter has been developed for emergency response. ► The detector enables fast readouts and shows highly favorable dosimetric properties. ► A conceptual design is described to produce maps of radioactive contamination from localized dose measurements in urban areas.

  10. Investigation of TL, OSL and PTTL properties of Mg2SiO4:Tb dosimeters

    International Nuclear Information System (INIS)

    Oguz, K. F.; Goekce, M.; Karali, T.; Harmansah, C.

    2010-01-01

    In this study thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of Mg 2 SiO 4 :Tb in the form of sintered pellets were investigated. Mg 2 SiO 4 :Tb is a recently developed dosimetric material which offers high sensitivity for TL and OSL in dosimetric applications. Thermoluminescence glow curve of Tb doped Mg 2 SiO 4 samples show a glow peak at about 200 degree Celsius with two small peaks at about 275 and 330 degree Celsius, respectively. OSL experiments showed that blue light (470 nm) is six times more efficient than green light (532 nm) to stimulate the OSL emission. The aim of this study was to determine the TL and OSL fading properties of Mg 2 SiO 4 : Tb using OSL and TL methods. In addition, PTTL properties of the Mg 2 SiO 4 : Tb was investigated by using blue LEDs, UV lamp and blue laser. Investigations on the fading properties also showed that the TL signal fades % 10 in a period of 1 month and OSL signal fades % 10 in a period of 3 month, which then the signal remains relatively stable for longer periods.

  11. OSL Age Determination of the Hearths in a Bronze Age Dwelling Site by using Bayesian Statistics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Jin [Neosiskorea Co. Ltd., Seoul (Korea, Republic of); Yang, Hye Jin [Baekje Cultural Properties Research Institute, Gongju (Korea, Republic of); Hong, Duk Geun [Kangwon National University, Chuncheon (Korea, Republic of)

    2011-06-15

    OSL dating for three hearths having the sequence of use and discard in No. 29 and 29-1 dwelling sites at Sogol cultural site was carried out. Resulting from the deconvolution of natural CW-OSL decay curve and thermal zeroing test, it was turned out that OSL signal was entirely composed of the heat- and light-sensitive fast component with high photoionization cross-section and all quartz OSL signals were thermally bleached under 300 .deg. C which is the minimum temperature related to heating and cooking in Bronze age. After dose recovery test and plateau test, paleodose of each hearth sample was evaluated by using SAR method, and OSL age was determined from the ratio of paleodose to annual dose rate. For the purpose of the precision improvement of OSL age, Bayesian statistics was applied to each hearth's age and the archaeological sequence information. Finally, it could be concluded to the accurate use period of each hearth from the resultant OSL ages.

  12. OSL Age Determination of the Hearths in a Bronze Age Dwelling Site by using Bayesian Statistics

    International Nuclear Information System (INIS)

    Kim, Myung Jin; Yang, Hye Jin; Hong, Duk Geun

    2011-01-01

    OSL dating for three hearths having the sequence of use and discard in No. 29 and 29-1 dwelling sites at Sogol cultural site was carried out. Resulting from the deconvolution of natural CW-OSL decay curve and thermal zeroing test, it was turned out that OSL signal was entirely composed of the heat- and light-sensitive fast component with high photoionization cross-section and all quartz OSL signals were thermally bleached under 300 .deg. C which is the minimum temperature related to heating and cooking in Bronze age. After dose recovery test and plateau test, paleodose of each hearth sample was evaluated by using SAR method, and OSL age was determined from the ratio of paleodose to annual dose rate. For the purpose of the precision improvement of OSL age, Bayesian statistics was applied to each hearth's age and the archaeological sequence information. Finally, it could be concluded to the accurate use period of each hearth from the resultant OSL ages

  13. BeOSL system for personal dosimetry : dosimetric characteristics and practical application

    International Nuclear Information System (INIS)

    Mende, E.

    2015-10-01

    Full text: BeOSL system of Dosimetric s is very easy to use, assimilate and maintain. Our dosimeter defines a milestone in the supervision of personal equivalent dose of Hp (10) and Hp (0.07) it covers the range of total energy of 16 KeV to 10 MeV. For this energy range is exceptional in its energy dependence for official personal dosimetry. The BeOSL system consists of two modules, one of them is the BeOSL reader that measures the radiation exposure using the latest technology, optically stimulated luminescence (OSL). The reading is extremely fast; it does not require consumables such as nitrogen or other. The detector material is beryllium oxide (Be O); this is an OSL material tissue equivalent and therefore is ideal for personal dosimetry. The BeOSL technology allows multiple readings of the dosimeter (re-read) to verify the dose or archive the dosimeter. One of the biggest advantages of BeOSL system is its modular concept allows the system to run as a manual solution or as a complete automated robotic system, which can be filled with up to 5,000 dosimeters as bulk cargo. (Author)

  14. LM-OSL signals from some insulators: an analysis of the dependency of the detrapping probability on stimulation light intensity

    DEFF Research Database (Denmark)

    Bulur, E.; Bøtter-Jensen, L.; Murray, A.S.

    2001-01-01

    Optically stimulated luminescence (OSL) signals from various insulators including quartz, Al2O3 : C, BeO and NaCl have been studied using the linear modulation OSL (LM-OSL) technique. LM-OSL is based on the linear increase of the stimulation light power from zero to a maximum during the measurement...... is not always correct. The initial decay rates of the blue (similar to 470 nm) light stimulated constant power OSL decay curves were examined to test the relation between the detrapping rates and the stimulation light intensity. In SiO2, Al2O3 : C and BeO a linear relation between the detrapping rates....... The resultant OSL curve initially increases and then decays after reaching a maximum, The analysis of LM-OSL data usually assumes a linear relationship between the detrapping rate and the stimulation light intensity. However, experiments carried out using various insulators have shown that this assumption...

  15. OSL response bleaching of BeO samples, using fluorescent light and blue LEDs

    International Nuclear Information System (INIS)

    Groppo, Daniela Piai; Caldas, Linda V.E.

    2015-01-01

    The optically stimulated luminescence (OSL) is widely used as a dosimetric technique for many applications. In this work, the OSL response bleaching of BeO samples was studied. The samples were irradiated using a beta radiation source ( 90 Sr+ 90 Y); the bleaching treatments (fluorescent light and blue LEDs) were performed, and the results were compared. Various optical treatment time intervals were tested until reaching the complete bleaching of the OSL response. The best combination of the time interval and bleaching type was analyzed. (author)

  16. Pilot study: relative dose of the TLD, OSL and Radiochromic film applied in CT exams dosimetry

    International Nuclear Information System (INIS)

    Kikuti, C.F.; Maia, R.S.I.; Romano, R.F.T.; Daros, K. A.C.

    2015-01-01

    At DDI/UNIFESP, the abdomen and chest CT exams correspond to 38% of the exams, becoming the focus of studies. The aim of this study is to assess the relative dose using TLDs, OSLs and RF for the evaluation of the dose distribution in the skin in abdomen CT exams. The simulation of the CT exam was performed in an anthropomorphic phantom, using a CT scanner Philips, Brilliance/64 and TLDs, OSLs and RF fixed along the sagittal axis of the phantom. The OSLs showed similar performance to the TLDs and RF shows low accuracy, resulting in an average value (0.927±0.022). (author)

  17. OSL response bleaching of BeO samples, using fluorescent light and blue LEDs

    International Nuclear Information System (INIS)

    Groppo, D P; Caldas, L V E

    2016-01-01

    The optically stimulated luminescence (OSL) is widely used as a dosimetric technique for many applications. In this work, the OSL response bleaching of BeO samples was studied. The samples were irradiated using a beta radiation source ("9"0Sr+"9"0Y); the bleaching treatments (fluorescent light and blue LEDs) were performed, and the results were compared. Various optical treatment time intervals were tested until reaching the complete bleaching of the OSL response. The best combination of the time interval and bleaching type was analyzed. (paper)

  18. Pilot study: relative dose of the TLD, OSL and Radiochromic film applied in CT exams dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kikuti, C.F. [Universidade Federal do Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Hospital Universitario Maria Aparecida Pedrossian; Maia, R.S.I.; Romano, R.F.T.; Daros, K. A.C., E-mail: daros.kellen@unifesp.br [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Departamento de Diagnostico por Imagem

    2015-07-01

    At DDI/UNIFESP, the abdomen and chest CT exams correspond to 38% of the exams, becoming the focus of studies. The aim of this study is to assess the relative dose using TLDs, OSLs and RF for the evaluation of the dose distribution in the skin in abdomen CT exams. The simulation of the CT exam was performed in an anthropomorphic phantom, using a CT scanner Philips, Brilliance/64 and TLDs, OSLs and RF fixed along the sagittal axis of the phantom. The OSLs showed similar performance to the TLDs and RF shows low accuracy, resulting in an average value (0.927±0.022). (author)

  19. Integrated circuits from mobile phones as possible emergency OSL/TL dosimeters

    International Nuclear Information System (INIS)

    Sholom, S.; McKeever, S.W.S.

    2016-01-01

    In this article, optically stimulated luminescence (OSL) data are presented from integrated circuits (ICs) extracted from mobile phones. The purpose is to evaluate the potential of using OSL from components in personal electronic devices such as smart phones as a means of emergency dosimetry in the event of a large-scale radiological incident. ICs were extracted from five different makes and models of mobile phone. Sample preparation procedures are described, and OSL from the IC samples following irradiation using a 90 Sr/ 90 Y source is presented. Repeatability, sensitivity, dose responses, minimum measurable doses, stability and fading data were examined and are described. A protocol for measuring absorbed dose is presented, and it was concluded that OSL from these components is a viable method for assessing dose in the days following a radiological incident. (authors)

  20. OSL surface exposure dating of a lithic quarry in Tibet: Laboratory validation and application

    DEFF Research Database (Denmark)

    Gliganic, L.A.; Meyer, M.C.; Sohbati, R.

    2018-01-01

    developed OSL Surface exposure dating technique (OSL-Surf) to date flake scars at lithic quarry sites. We performed the first quantitative validation of the model describing the OSL-Surf dating technique using a controlled laboratory experiment. Our results show that longer laboratory bleaching durations......-depth profile that could be used to calibrate the model to estimate the exposure duration of a flake scar associated with human exploitation of the area. Finally, we observe that the μ parameter of the OSL-Surf model varies considerably between the laboratory-bleached and two naturally daylight-bleached...... datasets, despite having identical lithologies. We thus infer that, in addition to lithological controls, the μ parameter is primarily sensitive to the daylight irradiation geometry and only weakly dependent on spectrum of the incident light; this interpretation implies a narrow effective bleaching...

  1. INTEGRATED CIRCUITS FROM MOBILE PHONES AS POSSIBLE EMERGENCY OSL/TL DOSIMETERS.

    Science.gov (United States)

    Sholom, S; McKeever, S W S

    2016-09-01

    In this article, optically stimulated luminescence (OSL) data are presented from integrated circuits (ICs) extracted from mobile phones. The purpose is to evaluate the potential of using OSL from components in personal electronic devices such as smart phones as a means of emergency dosimetry in the event of a large-scale radiological incident. ICs were extracted from five different makes and models of mobile phone. Sample preparation procedures are described, and OSL from the IC samples following irradiation using a (90)Sr/(90)Y source is presented. Repeatability, sensitivity, dose responses, minimum measureable doses, stability and fading data were examined and are described. A protocol for measuring absorbed dose is presented, and it was concluded that OSL from these components is a viable method for assessing dose in the days following a radiological incident. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Measurements of eye lens doses in interventional cardiology using OSL and electronic dosemeters

    International Nuclear Information System (INIS)

    Sanchez, R.M.; Vano, E.; Fernandez, J.M.; Ginjaume, M.; Duch, M.A.

    2014-01-01

    The purpose of this paper is to test the appropriateness of OSL and electronic dosemeters to estimate eye lens doses at interventional cardiology environment. Using TLD as reference detectors, personal dose equivalent was measured in phantoms and during clinical procedures. For phantom measurements, OSL dose values resulted in an average difference of 215 % vs. TLD. Tests carried out with other electronic dosemeters revealed differences up to ±20 % versus TLD. With dosemeters positioned outside the goggles and when TLD doses were >20 μSv, the average difference OSL vs. TLD was 29 %. Eye lens doses of almost 700 μSv per procedure were measured in two cases out of a sample of 33 measurements in individual clinical procedures, thus showing the risk of high exposure to the lenses of the eye when protection rules are not followed. The differences found between OSL and TLD are acceptable for the purpose and range of doses measured in the survey (authors)

  3. Sample dependent correlation between TL and LM-OSL in Al2O3:C

    International Nuclear Information System (INIS)

    Dallas, G.I.; Polymeris, G.S.; Stefanaki, E.C.; Afouxenidis, D.; Tsirliganis, N.C.; Kitis, G.

    2008-01-01

    Al 2 O 3 :C single crystals are known to exhibit different, sample dependent, glow-curve shapes. The relation between the Thermoluminescence (TL) traps and the linear modulated optically stimulation luminescence (LM-OSL) traps is of high importance. In the present work a correlation study is attempted using 23 single crystals with dimensions between 400 and 500μm. The correlation study involved two steps. In the first step, both TL glow curves and LM-OSL decay curves are deconvoluted and a one-to-one correlation between TL peaks and LM-OSL components is attempted. In the second step the TL glow-curves are corrected for thermal quenching, the corrected curves are deconvoluted and a new correlation between TL and LM-OSL individual components is performed

  4. Passive dosimetry: introduction of a new dosimeter based on OSL technology

    International Nuclear Information System (INIS)

    Archambault, V.; Le Roy, G.; Prugnaud, B.

    2005-01-01

    A new passive dosimeter based on OSL technology has been introduced on the French market. In this article are described: the technology and the material on which this new detector relied, the dosimeter itself. (author)

  5. More on the TR-OSL signal from BeO ceramics

    International Nuclear Information System (INIS)

    Bulur, Enver

    2014-01-01

    Time Resolved Optically Stimulated Luminescence (TR-OSL) from BeO ceramics was investigated using blue (445 nm) and near-IR light (852 nm) for stimulation. Stimulation spectrum of the TR-OSL signal – as measured in the interval 700 to 420 nm- was observed to increase monotonically with the decreasing stimulation wavelength. In addition to the “fast” and “slow” components observed with blue light stimulation, IR stimulated TR-OSL spectra of irradiated BeO ceramics were observed to have two components with average lifetimes around ∼2.5 μs and ∼17 μs. Emission spectra of the both IR stimulated TR-OSL components were observed to have a broad emission band peaking around 330 nm. Thermal stability of the IR stimulated TR-OSL signal was studied by making preheating experiments in the range from 100 °C to 190 °C. It was observed that the IR stimulated OSL signal is stable up to ∼150 °C and decay afterwards. Radiation dose response of the IR stimulated luminescence signal was obtained in the range from 5 to 500 Gy. Both blue and IR stimulated TR-OSL signals grew up to 100 Gy and exhibited saturation for higher doses. Additionally, measurement temperature dependence of the components was also investigated and for the ∼2 μs component thermal assistance with activation energy around 0.16 eV was observed. It seems that the fast component of the blue stimulated TR-OSL component can be correlated to the ∼2 μs IR stimulated TR-OSL component. - Highlights: • IR Stimulated Time-Resolved OSL from BeO was studied. • Two components with lifetimes ∼2 and ∼17us were observed. • IR stimulated TR-OSL signal is found to be stable up to 150 °C. • Thermal quenching energy of the 2us component was found as 0.16 eV

  6. Implementation of a OSL dosimetry laboratory at IRD/CNEN-BR

    International Nuclear Information System (INIS)

    Moura, Jose; Alencar, Marcus A. Vallim de; Mauricio, Claudia L.P.; Hunt, John

    2005-01-01

    The optically stimulated luminescence (OSL) it is a phenomenon characterized by the luminous emission of an insulating material or semiconductor, during your exhibition to the light, after it being previously exposed to the ionizing radiation. This phenomenon has been used more and more in the dosimetry of the ionizing radiations, why the intensity OSL of some materials is proportional to the absorbed dose in these. The processes OSL and thermoluminescence (TL) they only differ in the stimulation form for light emission. One of the advantages of the OSL process in relation to the traditional technique of TL dosimetry is the no complete destruction of the information of the absorbed dose in the material during the reading. Following this world tendency, the External Individual Monitoring Service of the Institute of Radioprotection and Dosimetry (SEMEX/IRD) implemented the OSL dosimetry laboratory. The acquired reader was the reader model LAUGHTER TL/OSL-GIVE-15B/C. With that reader it is possible to do readings TL and OSL. After the installation of the equipment in a darkroom with temperature and humidity controlled, they were made the preliminary tests with the equipment and the laboratory became operational. After this first stage, they were initiate the studies with the Al 2 O 3 :C dosimeters by Harshaw under the denomination TLD 500. The reading parameters and thermal treatment were optimized to study the applicability of OSL technique with the TLD 500 dosimeter for the use in environmental monitoring. It was also verified the linearity of the system for high doses (10 mGy-1 Gy) seeking your use in radiotherapy, as well as the effect of the thermal treatment in the OSL signal of the Al 2 O 3 :C dosimeter. The results prove the possibility of use of this system in environmental monitoring. The reproductivity of the system for the air kerma value of 100 mGy, considering a degree of confidence of 95%, was to 4,8% for OSL readings and 5,6% for TL. In the two cases

  7. The preliminary application of OSL in comparison with TL for authentication of ancient Chinese bricks

    International Nuclear Information System (INIS)

    Leung, P.L.; Tang Qiang; Li, Mike; Zhang Chunxiang

    2005-01-01

    The single-aliquot regenerative-dose (SAR) protocol with optically stimulated luminenscence (OSL) was applied to measure the equivalent dose (ED) of ancient Chinese bricks ranging in age from 180 to 1600 years. In the protocol, sensitivity changes can be corrected by using OSL response to a fixed test dose during measurement. For comparative study between OSL and TL, thermoluminescence (TL) measurement procedures were also applied to determine the paleodose of the bricks. Both results of OSL and TL are in agreement with the known ages of the bricks, and the paleodose ratios(ED OSL / ED TL ) are between 0.96 and 1.21, mean value 1.08+/-0.02. The annual doses of the bricks, estimated by the paleodoses and the known ages, range from 5.07 to 6.79mGy/a, comparable with the measured annual dose values of the bricks. Therefore, it is concluded that the SAR protocol is a rapid and effective OSL technique to authenticate Chinese bricks

  8. A comparative study between OSL and TL techniques for the dating of ancient chinese bricks

    International Nuclear Information System (INIS)

    Leung, P.L.; Li, M.; Tang Qiang; Zhang Chunxiang

    2004-01-01

    The single-aliquot regenerative-dose (SAR) protocol to the optically stimulated luminescence (OSL) was applied to measure the paleodose of ancient Chinese bricks with an age range from 180 to 1600 years. In the protocol, sensitivity changes can be corrected by using OSL response to a fixed test dose during measurement. For comparative study between OSL and TL, thermoluminescence (TL) measurement procedures were also applied to determine the paleodose of the bricks. Both results of OSL and TL are in good agreement with, and the paleodose ratios (De OSL /De TL ) are between 0.96 and 1.21, with a mean value of 1.08 ± 0.07. The annual dose of the bricks, estimated by the paleodoses and the known ages, ranges from 5.07 to 6.85 mGy/a, comparable with the measured annual dose values. Therefore, it is concluded that the SAR protocol is a rapid and effective OSL technique to authenticate Chinese bricks. (authors)

  9. TL and OSL studies of carbon doped magnesium aluminate (MgAl2O4:C)

    Science.gov (United States)

    Raj, Sanu S.; Mishra, D. R.; Soni, Anuj; Grover, V.; Polymeris, G. S.; Muthe, K. P.; Jha, S. K.; Tyagi, A. K.

    2016-10-01

    The MgAl2O4:C has been synthesized by using two different methods by electron gun and vacuum assisted melting of MgAl2O4 in presence of graphite. The MgAl2O4:C phosphor thus developed by these two different methods have similar types of the TL/OSL defects with multiple overlapping TL glow peaks from 100 °C to 400 °C. The Computerized Curve De-convolution Analysis (CCDA) has been used to measure TL parameters such as thermal trap depth, frequency factor and order of kinetic associated with charge transfer process in TL phenomenon. The investigated TL/OSL results show that these two methods of incorporating carbon in MgAl2O4 have generated closely resemble the defects of similar types in MgAl2O4:C lattice. However, the MgAl2O4:C synthesized by electron gun shows relatively larger concentration of the TL/OSL defects as compared to MgAl2O4:C synthesized using vacuum assisted melting method. The photo-ionization cross-section (PIC) associated with fastest OSL component of MgAl2O4: C is found to be ∼ 0.5 times than that of fastest OSL component of commercially available dosimetric grade α-Al2O3:C. The MgAl2O4:C thus developed shows good dynamic OSL dose linearity from few mGy to 1 Gy. This work reveals that MgAl2O4:C could be developed as potential tissue equivalent OSL / TL material.

  10. TL and OSL dosimetric properties of Opal gemstone for gamma radiation dosimetry

    International Nuclear Information System (INIS)

    Antonio, Patrícia L.; Gronchi, Claudia C.; Oliveira, Raquel A.P.; Khoury, Helen J.; Caldas, Linda V.E.

    2016-01-01

    In this work, the response of the natural material Opal was studied in relation to its thermoluminescence (TL) and optically stimulated luminescence (OSL), after exposure to the gamma radiation of a "6"0Co source. The structure of the powdered Opal was verified using the X-ray diffraction, scanning electronic microscopy and energy-dispersive X-ray spectroscopy techniques. The material, in its stone form, was turned into powder and mixed to Teflon (also in powder) in three different concentrations, and then pellets were manufactured. The aim of this work was to evaluate the response of these pellets in high-doses of gamma radiation beams, and to observe their possible application as dosimeters, using the TL and OSL techniques. The dosimetric properties of the samples were analyzed by means of different tests, as: TL emission curves and OSL signal decay curves, reproducibility of TL and OSL response, minimum detectable dose, TL and OSL dose–response curves (5 Gy–10 kGy), and fading. The results obtained in this work, for the TL and OSL phenomena, demonstrated that the pellets of Opal + Teflon present an adequate performance e possibility of use as dosimeters in beams of high-dose gamma radiation. - Highlights: • The XRD, SEM and EDX techniques were used to investigate powdered Opal. • Pellets of three different concentrations of Opal and Teflon were studied. • The dosimetric properties of the Opal + Teflon pellets were verified. • TL and OSL techniques were used to analyze the characteristics of the pellets. • Pellets of concentration of 2:1 (Opal:Teflon) presented the most adequate results.

  11. Thermal activation of OSL as a geothermometer for quartz grain heating during fault movements

    CERN Document Server

    Rink, W J; Rees-Jones, J; Schwarcz, H P

    1999-01-01

    In discussions of ESR dating of fault movements, there has been much debate whether zeroing of ESR signals is a mechanical shearing effect or caused by frictional heating. The OSL (optically stimulated luminescence) sensitivity of quartz is known to increase after heating. This thermal activation of dose response of the OSL in quartz should be useful as a geothermometer to test whether quartz particles in fault gouge had been heated. We tested the OSL sensitivities of quartz from fault gouge, and from a control (quartz grains from sandstone) and were able to show heat-induced enhancement of OSL sensitivity to a test dose. We observed that relative enhancement of OSL dose response (ratio of heated to unheated single aliquots) is significantly less for the finest grains (45-75 and 100-150 mu m) compared with coarser grains (150-250 mu m). These data are consistent with a model of zeroing of the quartz grains during faulting, by frictional heating localized to the grain boundaries, which would be expected to aff...

  12. OSL, TL and IRSL emission spectra of sedimentary quartz and feldspar samples

    International Nuclear Information System (INIS)

    Lomax, Johanna; Mittelstraß, Dirk; Kreutzer, Sebastian; Fuchs, Markus

    2015-01-01

    This contribution presents a variety of different luminescence emission spectra from sedimentary feldspar and quartz samples under various stimulation modes. These are green stimulated quartz (OSL-) spectra, quartz TL spectra, feldspar IRSL and post-IR IRSL spectra. A focus was set at recording OSL and IRSL spectra at elevated stimulation temperatures such as routinely applied in luminescence dating. This was to test whether optical stimulation at elevated temperatures results in a shift of emission peaks. For OSL emissions of quartz, this has so far not been tested. In case of feldspar emissions, post-IR IRSL conditions, hence IRSL emissions at a low temperature, directly followed by high temperature post-IRSL emissions, are explicitly investigated. All spectra were recorded using a new system incorporated into a Lexsyg luminescence reader. Thus, this study, besides presenting new spectral data, also serves as a feasibility study for this new device. It is shown that (a) the new device is capable of automatically measuring different sorts of spectra, also at elevated temperatures, (b) known thermally and optically stimulated peak emissions of quartz and feldspar are confirmed, (c) obtained IRSL and OSL spectra indicate that there is no significant relation between peak emission and stimulation temperature. - Highlights: • We have measured OSL, IRSL and TL emission spectra of sedimentary quartz and feldspar samples. • Spectral analyses were performed at elevated stimulation temperatures. • Emission spectra show very little variation with stimulation temperatures.

  13. Angular dependence of the nanoDot OSL dosimeter

    International Nuclear Information System (INIS)

    Kerns, James R.; Kry, Stephen F.; Sahoo, Narayan; Followill, David S.; Ibbott, Geoffrey S.

    2011-01-01

    Purpose: Optically stimulated luminescent detectors (OSLDs) are quickly gaining popularity as passive dosimeters, with applications in medicine for linac output calibration verification, brachytherapy source verification, treatment plan quality assurance, and clinical dose measurements. With such wide applications, these dosimeters must be characterized for numerous factors affecting their response. The most abundant commercial OSLD is the InLight/OSL system from Landauer, Inc. The purpose of this study was to examine the angular dependence of the nanoDot dosimeter, which is part of the InLight system. Methods: Relative dosimeter response data were taken at several angles in 6 and 18 MV photon beams, as well as a clinical proton beam. These measurements were done within a phantom at a depth beyond the build-up region. To verify the observed angular dependence, additional measurements were conducted as well as Monte Carlo simulations in MCNPX. Results: When irradiated with the incident photon beams parallel to the plane of the dosimeter, the nanoDot response was 4% lower at 6 MV and 3% lower at 18 MV than the response when irradiated with the incident beam normal to the plane of the dosimeter. Monte Carlo simulations at 6 MV showed similar results to the experimental values. Examination of the results in Monte Carlo suggests the cause as partial volume irradiation. In a clinical proton beam, no angular dependence was found. Conclusions: A nontrivial angular response of this OSLD was observed in photon beams. This factor may need to be accounted for when evaluating doses from photon beams incident from a variety of directions.

  14. A new luminescence detection and stimulation head for the Risø TL/OSL reader

    International Nuclear Information System (INIS)

    Lapp, T.; Kook, M.; Murray, A.S.; Thomsen, K.J.; Buylaert, J.-P.; Jain, M.

    2015-01-01

    A new automated Detection And Stimulation Head (DASH) has been developed for the Risø TL/OSL luminescence reader to provide easy access to new technologies, new signals and new measurement methods. The automated DASH includes a filter changer and a detector changer that makes it possible to change stimulation filters (4 × 4 filter combinations possible) and detectors (3 detectors possible) as part of a measurements sequence. The new automated DASH with dedicated driver electronics does not affect the use of other attachments, and can be retrospectively fitted to existing Risø TL/OSL readers. - Highlights: • A new detection and stimulation head for the Risø TL/OSL reader is described. • An example of the use of the filter changer is presented. • The power and spatial uniformity of blue, green and IR stimulation are characterised. • The potential of an EMCCD camera detector is described.

  15. Optically stimulated luminescence (OSL) and some other luminescence images from granite slices exposed with radiations

    International Nuclear Information System (INIS)

    Hashimoto, T.; Notoya, S.; Ojima, T.; Hoteida, M.

    1995-01-01

    Optically stimulated luminescence (OSL) images of some X- and γ-irradiated granite slices were obtained using photon detection through a 570 nm bandpass filter with diode-laser excitation of 910 nm. Alternative photo-induced phosphorescence (PIP) images, which were colour photographed immediately after the sunlight exposure of slice samples, were also found to be helpful in the observation of the luminescence properties and to filter selection for OSL measurements. These OSL and PIP images were compared with some other colour luminescence images, including thermoluminescence images (TLCI) and after-glow images (AGCI). It was obvious that there exists a variety of coloured emissions derived mainly from feldspar constituents and these were found to be dependent on the geological history or metamorphism of the granites. (Author)

  16. Correlation between TL and OSL properties of CaF2:N

    International Nuclear Information System (INIS)

    Polymeris, George S.; Kitis, George; Tsirliganis, Nestor C.

    2006-01-01

    Natural CaF 2 is very well known thermoluminescent (TL) material, since it has been extensively used as a dosimeter. Its basic advantage is the exhibited high TL sensitivity. In the present work, the optically stimulated luminescence (OSL) sensitivity of this material was studied by exposing it to environmental radiation for time intervals of few hours up to a few days, and was found to be very high. By analyzing the TL glow curves and the OSL decay curves into their individual glow-peaks and components respectively, a relation between specific glow-peaks and OSL components was established. An intense thermal transfer effect occurring during optical stimulation at high temperature was observed and an explanation is offered according to existing models

  17. Retrospective dosimetry using Japanese brick quartz: A way forward despite an unstable fast decaying OSL signal

    DEFF Research Database (Denmark)

    Fujita, Hiroki; Jain, Mayank; Murray, A.S.

    2011-01-01

    signals has been carried out towards identification of common source traps. It is observed that OSL from Japanese brick quartz shows unusual luminescence characteristics; in particular, the initial fast decaying OSL signal contains a dominant (>90%) thermally unstable component related to the 85 °C TL...... peak, which necessitates a prior heat treatment. A single-aliquot regenerative-dose (SAR) protocol is developed and tested using thermal treatments intended to isolate a stable dosimetric signal. A minimum detection limit of 65 mGy is then estimated using this protocol. Following irradiation using 60Co...... of Japanese brick quartz examined here can be used to derive precise estimates of accident dose, and, possibly to distinguish between sources of gamma radiation in a nuclear accident. To our knowledge, this is the first report on the existence of an unstable fast decaying OSL signal in quartz derived from...

  18. Correlation of basic TL, OSL and IRSL properties of ten K-feldspar samples of various origins

    Energy Technology Data Exchange (ETDEWEB)

    Sfampa, I.K. [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece); Polymeris, G.S. [Institute of Nuclear Sciences, Ankara University, 06100 Besevler, Ankara (Turkey); Pagonis, V. [McDaniel College, Physics Department, Westminster, MD 21157 (United States); Theodosoglou, E. [Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Tsirliganis, N.C. [Laboratory of Radiation Applications and Archaeological Dating, Department of Archaeometry and Physicochemical Measurements, ‘Athena’ R.& I.C., Kimmeria University Campus, GR67100 Xanthi (Greece); Kitis, G., E-mail: gkitis@auth.gr [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece)

    2015-09-15

    Highlights: • OSL and IRSL bleaching behavior of ten K-feldspar samples is presented. • OSL and IRSL decay curves were component resolved using tunneling model. • The growth of integrated OSL and IRSL signals versus time was described by new expression based on tunneling model. • Correlation between TL, OSL and IRSL signals and of all properties with K-feldspar structure was discussed. - Abstract: Feldspars stand among the most widely used minerals in dosimetric methods of dating using thermoluminescence (TL), optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL). Having very good dosimetric properties, they can in principle contribute to the dating of every site of archaeological and geological interest. The present work studies basic properties of ten naturally occurring K-feldspar samples belonging to three feldspar species, namely sanidine, orthoclase and microcline. The basic properties studied are (a) the influence of blue light and infrared stimulation on the thermoluminescence glow-curves, (b) the growth of OSL, IRSL, residual TL and TL-loss as a function of OSL and IRSL bleaching time and (c) the correlation between the OSL and IRSL signals and the energy levels responsible for the TL glow-curve. All experimental data were fitted using analytical expressions derived from a recently developed tunneling recombination model. The results show that the analytical expressions provide excellent fits to all experimental results, thus verifying the tunneling recombination mechanism in these materials and providing valuable information about the concentrations of luminescence centers.

  19. Luminescence characteristics of quartz from the Southern Kenyan Rift Valley: Dose estimation using LM-OSL SAR

    International Nuclear Information System (INIS)

    Choi, J.H.; Duller, G.A.T.; Wintle, A.G.; Cheong, C.-S.

    2006-01-01

    Linearly modulated (LM) optically stimulated luminescence (OSL) measurements have revealed that some sedimentary quartz samples from the Kenyan Rift Valley do not have a fast OSL component, but contain a medium component and several slow components. It was impossible to recover a known dose for these samples using the conventional single-aliquot regenerative-dose (SAR) procedure. The dose-response curves and continuous wave (CW) OSL decay curves for these samples showed several undesirable properties for dating. We have compared various luminescence characteristics of these samples with other quartz samples from elsewhere in the world for which the SAR procedure has been shown to be appropriate; the latter were dominated by a fast OSL component. The characteristics include photoionisation cross-sections for each component and the relative proportions of the different components in the initial and total OSL signals. It was found that those samples that had greater than 90% of the initial 0.8 s of their OSL signal from the fast component were suitable for dating using the conventional SAR protocol. A novel method of displaying the relative contributions of the different OSL components in a ternary diagram is proposed. The thermal stability of each component was investigated using pulse-annealing experiments. We then examined the possibility of applying an LM-OSL SAR protocol to samples that have a substantial medium component

  20. Dosimetry in the multi kilo-Gray range using optically-stimulated luminescence (OSL) and thermally-transferred OSL from quartz

    International Nuclear Information System (INIS)

    Burbidge, C.I.; Cabo Verde, S.I.; Fernandes, A.C.; Prudencio, M.I.; Botelho, M.L.; Dias, M.I.; Cardoso, G.

    2011-01-01

    This study explores the potential for using photon-stimulated luminescence of quartz grains to retrospectively evaluate multi-kGy gamma radiation doses. Subsamples from two ceramic tiles were given 60 Co gamma doses of 1, 3, 5, 15 and 30 kGy (nominal), accompanied by PMMA dosimeters and quartz grains from a geological sample known to exhibit thermally-transferred optically-stimulated luminescence (TTOSL). Following gamma irradiation, quartz grains were prepared from each subsample. OSL and TTOSL signals were measured for different preheat temperatures, and following re-irradiation with beta doses designed to equal the nominal gamma doses. OSL responses to 10 Gy beta test doses were measured following each cycle of high dose irradiation. Gamma doses were predicted from the beta responses, to evaluate the effectiveness of retrospective dose evaluation for different signal integrals, preheat combinations, and dose intervals. The use of linear modulation limited maximum OSL signal levels to 1.5 x 10 6 cps without reducing detector sensitivity, for the measurement of smaller TTOSL signals. The dosimetric behaviour of the three samples differed significantly: the best results were obtained from the pre-prepared geological quartz. OSL signals evident at short stimulation times, which are conventionally used for dosimetry and dating, did not in general appear appropriate for dosimetry in the range of doses examined. They exhibited dose response characteristics that were highly preheat dependant and variable in form between samples, which contained rapidly saturating and/or non-monotonic components. Higher preheats, up to 300 o C, preferentially removed OSL and TTOSL signals evident at longer stimulation times: those that remained yielded growth in signal with dose to approximately 10 kGy, but the accuracy of retrospective dose determinations was variable. TTOSL signals evident at short stimulation times increased proportionally with dose when 300 o C preheats were used, up

  1. Study of optically stimulated luminescence (OSL) for radiation detection. Application to an optical fibre {gamma}-radiation sensor; Etude de la luminescence stimulee optiquement (OSL) pour la detection de rayonnements: application a un capteur a fibre optique de rayonnement {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Roy, O. [CEA Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Electronique et d`Instrumentation Nucleaire]|[Paris-7 Univ., 75 (France)

    1998-12-31

    This work shows up the usefulness of the Optically Stimulated Luminescence (OSL) to resolve radioprotection problems. We study the use of OSL as a gamma dosimetric technique with respect to the ALARA`s concept (As Low As Reasonably Achievable). A new approach based on optical fibers and luminescent materials showing OSL properties (closely related to Thermoluminescence phenomena) is presented in order to improve the remote real time dosimetry monitoring. Like thermoluminescent materials (TLD), OSL materials can trap charges under an irradiation (UV, X, {gamma},...). Instead of heating, the charges trapped are released by light stimulation and produce a visible luminescence which amount is proportional to trap the `data stored` left by irradiation, enabling the dose measurement. The OSL phenomenon offers the same advantages as TLD plus the interesting possibility of a remote optical stimulation. The end-user objective deals with the development of a {gamma}-radiation Optical FIber Sensor (OFS) for dose measurement which can offer new functionalities based on OSL materials coupled with an optical fiber. Rare earth doped Alkaline Earth Sulphides (AES), BAFX:EU{sup 2+} (X = Cl, Br, I) and halogen alkaline have been studied (crystalline form, synthesis techniques, influence of dopants and color centers). Their characteristics are presented and extensively discussed. A specific experimental set-up to characterise various OSL phosphors has been developed. It allows the study of sensitivity, linearity, time decay behaviour of OSL signal and zeroing time. A joint study of OSL and TL has shown the technical limitations as well as the thermal fading and the origin of the long zeroing time. An Optical Fiber Sensor (OFS) based on OSL and using MgS:Sm has been developed for practical applications on nuclear fields. Its specifications are presented and discussed, moreover improvements are proposed. (author) 320 refs.

  2. OSL and TL retrospective dosimetry with a fluorapatite glass-ceramic used for dental restorations

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Judas, Libor; Sukupova, Lucie

    2013-01-01

    Optically Stimulated Luminescence (OSL) and Thermoluminescence (TL) properties of a fluorapatite glass-ceramic have been investigated, with a view to developing a dose assessment technique for medical triage following unplanned exposures of individuals to ionizing radiation. The ceramic is an innovative material used in dental prostheses and restorations. It is strongly sensitive to radiation and the intensity of both the OSL and TL signals are proportional to the absorbed radiation dose. We focused on the optimization of the measuring procedure and investigated characteristics such as reproducibility, fading, minimum detectable dose (MDD), dose response and photon energy response of TL and OSL signals. The dental ceramic exhibited very good reproducibility (<5% at 2σ level) when measured and a linear dose response for a wide range of doses (50 mGy–20 Gy). The MDD values for the samples investigated were ∼5 mGy. The material is not tissue equivalent and the OSL and TL signals are strongly dependent on incident photon energy. Both the luminescence signals exhibited significant fading during the first few hours after irradiation. Its rate was dependent on the parameters of measurement. The results indicate that the material can be used for the purposes of accident dosimetry, however, the fading and photon energy response have to be properly corrected for a reliable dose assessment. - Highlights: ► A dental ceramic was considered as a retrospective and accident dosimeter. ► Dosimetry application was investigated using OSL and TL. ► TL and OSL signals are proportional to absorbed radiation dose. ► Accuracy is dependent on correction of fading and photon energy response

  3. Optically stimulated luminescence (OSL) from Ag-doped Li2B4O7 crystals

    International Nuclear Information System (INIS)

    Kananen, B.E.; Maniego, E.S.; Golden, E.M.; Giles, N.C.; McClory, J.W.; Adamiv, V.T.; Burak, Ya.V.; Halliburton, L.E.

    2016-01-01

    Optically stimulated luminescence (CW-OSL) is observed from Ag-doped lithium tetraborate (Li 2 B 4 O 7 ) crystals. Photoluminescence, optical absorption, and electron paramagnetic resonance (EPR) are used to identify the defects participating in the OSL process. As-grown crystals have Ag + ions substituting for Li + ions. They also have Ag + ions occupying interstitial sites. During a room-temperature exposure to ionizing radiation, holes are trapped at the Ag + ions that replace Li + ions and electrons are trapped at the interstitial Ag + ions, i.e., the radiation forms Ag 2+ (4d 9 ) ions and Ag 0 (4d 10 5s 1 ) atoms. These Ag 2+ and Ag 0 centers have characteristic EPR spectra. The Ag 0 centers also have a broad optical absorption band peaking near 370 nm. An OSL response is observed when the stimulation wavelength overlaps this absorption band. Specifically, stimulation with 400 nm light produces an intense OSL response when emission is monitored near 270 nm. Electrons optically released from the Ag 0 centers recombine with holes trapped at Ag 2+ ions to produce the ultraviolet emission. The OSL response is progressively smaller as the stimulation light is moved to longer wavelengths (i.e., away from the 370 nm peak of the absorption band of the Ag 0 electron traps). Oxygen vacancies are also present in the Ag-doped Li 2 B 4 O 7 crystals, and their role in the OSL process as a secondary relatively short-lived electron trap is described.

  4. OSL signal of IC chips from mobile phones for dose assessment in accidental dosimetry

    International Nuclear Information System (INIS)

    Mrozik, A.; Marczewska, B.; Bilski, P.; Książek, M.

    2017-01-01

    The rapid assessment of the radiation dose is very important for the prediction of biological effects after unintended exposition. The materials for use as dosimeters in accidental dosimetry should be everyday objects which are usually placed near the human body, for example mobile phones. IC (Integrated Circuit) chip is one of several electronic components of mobile phones which give a luminescent signal. The measurements of samples from different mobile phones and smartphones were conducted by optically stimulated luminescence (OSL) and thermoluminescence (TL) methods. The OSL measurement was performed in two ways: with readouts at room temperature and at 100 °C. This work is focused on determination of OSL dose response of IC chips, minimum detectable dose (MDD), OSL signal stability in the time after the exposition, its repeatability and sensitivity to light. Several tests of the assessment of unknown doses were also conducted. The readouts at 100 °C indicate the reducing of the fading of OSL signal in the first hours after irradiation in comparison with room temperature readouts. The obtained results showed relatively good dosimetric properties of IC chips: their high sensitivity to the ionizing radiation, linear dose response up to 10 Gy and a good reproducibility of OSL signal which can allow the dose recovery of doses less than 2 Gy in 14 days after an incident with the accuracy better than 25%. The fading is a drawback of IC chips and the fading factor should be considered when calculating the dose. - Highlights: • IC chips from smartphones demonstrated high potential for accidental dosimetry. • Minimum detectable dose was estimated as a value of 50 mGy. • Samples showed linear dose response for the dose range from 0.05 Gy up to 10 Gy.

  5. Thermal activation of OSL as a geothermometer for quartz grain heating during fault movements

    International Nuclear Information System (INIS)

    Rink, W.J.; Toyoda, S.; Rees-Jones, J.; Schwarcz, H.P.

    1999-01-01

    In discussions of ESR dating of fault movements, there has been much debate whether zeroing of ESR signals is a mechanical shearing effect or caused by frictional heating. The OSL (optically stimulated luminescence) sensitivity of quartz is known to increase after heating. This thermal activation of dose response of the OSL in quartz should be useful as a geothermometer to test whether quartz particles in fault gouge had been heated. We tested the OSL sensitivities of quartz from fault gouge, and from a control (quartz grains from sandstone) and were able to show heat-induced enhancement of OSL sensitivity to a test dose. We observed that relative enhancement of OSL dose response (ratio of heated to unheated single aliquots) is significantly less for the finest grains (45-75 and 100-150 μm) compared with coarser grains (150-250 μm). These data are consistent with a model of zeroing of the quartz grains during faulting, by frictional heating localized to the grain boundaries, which would be expected to affect smaller grains more than large ones. This argues against a zeroing model in which the entire fault gouge is heated by friction. Higher laboratory preheating of sandstone quartz reduces between-aliquot variability of OSL dose response in the unheated grains to nearly zero. Unheated coarsest fault gouge grains displayed virtually no among-aliquot variability, whereas fine grains showed much larger between-aliquot variability; as with the quartz sand, variability dropped to near zero after laboratory heating, suggesting that fine grains in fault gouge have experienced a wide range of natural thermal histories during faulting. This may present a problem for ESR dating of fault gouge using the plateau method

  6. OSL and IRSL characteristics of quartz and feldspar from southern California, USA

    International Nuclear Information System (INIS)

    Lawson, Michael J.; Roder, Belinda J.; Stang, Dallon M.; Rhodes, Edward J.

    2012-01-01

    Southern California comprises of a wide range of diverse landscapes and environments, from high mountains with glacial and periglacial sediments to deserts with large sand dunes, extensive alluvial fans and ephemeral playas. Highly active tectonic processes has exposed ancient (c. 2 Ga) plutonic and metamorphic basement from deep within the crust, while similar Palaeozoic, Mesozoic and Cenozoic rocks are also common. A rich array of volcanic lithologies extending into the late Quaternary complement many thick sedimentary sequences that formed in equally diverse ancient environments typical of an accreting active continental margin. In some locations, notably in the Coachella Valley close to Palm Springs and the Salton Sea, low OSL sensitivity and poor characteristics restrict the application of the quartz SAR protocol to date late Pleistocene and Holocene fluvial sediments. In other locations such as the Malibu coastline, high sensitivity of the quartz OSL signal is observed, despite local source rocks being dominated by volcanic lithologies. Problems of poor quartz characteristics, along with uncertainty in predicting quartz OSL behavior for future dating campaigns poses a significant problem for projects, in particular for neotectonic contexts. While K-feldspar has been used extensively to date eolian and fluvial sediments in southern California, little information regarding signal stability is available. We explore the characteristics of both quartz and feldspar sub-samples from eolian, fluvial, lacustrine environments, in order to help develop mineral selection criteria for optical dating applications and clarify these issues. The importance of radiation quenching in quartz grains recently eroded from bedrock and the role of fires in enhancing OSL sensitivity are considered. The relative bleachability of quartz and feldspar fractions, along with thermal stability considerations is discussed. A simple test for quartz OSL signal contamination based on thermal

  7. A single-aliquot regenerative-dose method based on IR (1.49 eV) bleaching of the fast OSL component in quartz

    DEFF Research Database (Denmark)

    Jain, M.; Murray, A.S.; Bøtter-Jensen, L.

    2005-01-01

    In the optically stimulated luminescence (OSL) dating of quartz, the presence of significant medium and slow components in the initial-OSL signal (first 0.8 s or so) can give rise to erroneous dose estimates. Thus it is desirable to develop a dose estimation method that is based on the OSL from t...

  8. Study of optically stimulated luminescence (OSL) for radiation detection. Application to an optical fibre γ-radiation sensor

    International Nuclear Information System (INIS)

    Roy, O.

    1998-01-01

    This work shows up the usefulness of the Optically Stimulated Luminescence (OSL) to resolve radioprotection problems. We study the use of OSL as a gamma dosimetric technique with respect to the ALARA's concept (As Low As Reasonably Achievable). A new approach based on optical fibers and luminescent materials showing OSL properties (closely related to Thermoluminescence phenomena) is presented in order to improve the remote real time dosimetry monitoring. Like thermoluminescent materials (TLD), OSL materials can trap charges under an irradiation (UV, X, γ,...). Instead of heating, the charges trapped are released by light stimulation and produce a visible luminescence which amount is proportional to trap the 'data stored' left by irradiation, enabling the dose measurement. The OSL phenomenon offers the same advantages as TLD plus the interesting possibility of a remote optical stimulation. The end-user objective deals with the development of a γ-radiation Optical FIber Sensor (OFS) for dose measurement which can offer new functionalities based on OSL materials coupled with an optical fiber. Rare earth doped Alkaline Earth Sulphides (AES), BAFX:EU 2+ (X = Cl, Br, I) and halogen alkaline have been studied (crystalline form, synthesis techniques, influence of dopants and color centers). Their characteristics are presented and extensively discussed. A specific experimental set-up to characterise various OSL phosphors has been developed. It allows the study of sensitivity, linearity, time decay behaviour of OSL signal and zeroing time. A joint study of OSL and TL has shown the technical limitations as well as the thermal fading and the origin of the long zeroing time. An Optical Fiber Sensor (OFS) based on OSL and using MgS:Sm has been developed for practical applications on nuclear fields. Its specifications are presented and discussed, moreover improvements are proposed. (author)

  9. Relative response of TL and component-resolved OSL to alpha and beta radiations in annealed sedimentary quartz

    International Nuclear Information System (INIS)

    Polymeris, George S.; Afouxenidis, Dimitrios; Raptis, Spyridoula; Liritzis, Ioannis; Tsirliganis, Nestor C.; Kitis, George

    2011-01-01

    Knowledge of the relative luminescence response to alpha and beta radiation is very important in TL and OSL dating. In the present study the relative alpha to beta response is studied in a sedimentary quartz sample, previously fired at 900 deg. C for 1 h, in the dose region between 1 and 128 Gy, for both thermoluminescence (TL) and linearly modulated optically stimulated luminescence (LM - OSL). The LM - OSL measurements were performed at room temperature and at 125 deg. C. All OSL signals were deconvolved into their individual components. Comparison of OSL curves after alpha and beta irradiation strongly supports that quartz OSL components follow first order kinetics in both cases. In the case of TL, the relative alpha to beta response is found to be very different for each TL glow-peak, but it does not depend strongly on irradiation dose. In the case of LM - OSL measurements, it is found that the relative behaviour of the alpha to beta response is different for three distinct regions, namely the fast OSL component, the region of medium OSL component originating from the TL glow-peak at 110 deg. C when stimulation takes place at room temperature and finally the region of slow OSL component. Following stimulation at ambient temperature, the relative alpha to beta response of all components was not observed to depend significantly on dose, with the value of ratio being 0.03 and a tendency to decrease with increasing dose. However, in the case of measurements performed at 125 deg. C, the relative response of the fast components is much enhanced, and for the remaining components it increases with increasing dose. Special care must be taken to examine the relative alpha to beta response of the fast component at 125 deg. C which contrasts the relative response of the TL peak at ca. 325 deg. C. The implications for the dating of annealed quartz are also briefly discussed. - Highlights: → Relative alpha to beta response for TL and LM-OSL is studied in annealed

  10. A luminescence imaging system for the routine measurement of single-grain OSL dose distributions

    DEFF Research Database (Denmark)

    Kook, Myung Ho; Lapp, Torben; Murray, Andrew

    2015-01-01

    the potential of an electron multiplying charge-coupled device (EMCCD), providing extremely low level light detection. We characterize the performance of the device by discussing reproducibility and evaluating uncertainties in OSL signals. Finally we derive a typical single grain natural dose distribution...

  11. Preliminary results on TL and OSL aluminium oxide dosimeters developed at IPEN

    Energy Technology Data Exchange (ETDEWEB)

    Fukumori, David T.; Yoshito, Walter K.; Ussui, Valter; Lazar, Dolores R.R.; Campos, Leticia L., E-mail: fukumori@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The aluminum oxide composes the modern TL and OSL radiation dosimeters. TL and OSL phenomena are related to chemical elements in the crystalline structure of {alpha}-Al{sub 2}O{sub 3}. The aim of this work was to develop materials based on aluminum oxide for use in TL and OSL dosimetry. The studies included the dosimetric properties of alumina samples obtained by electro fusion, adsorption and coprecipitation. Electro fused alumina commercially available as abrasive particles was used to produce the pellets by glass sintering. Adsorption and coprecipitation were the methods used to insert metal ions to alumina. The best results were achieved with electro fused alumina and Tm{sup 3+} doped Al{sub 2}O{sub 3} pellets. The electro fused alumina-glass pellets show TL and OSL signals and the TL curve has two peaks. Its minimum detectable radiation dose is 7.2 mGy and the linearity of TL response as function of dose is up to about 800 mGy. The {alpha}-Al{sub 2}O{sub 3}:Tm pellets produced by sintering at 1550 deg C presented a meaningful TL glow curve so that it is worth studying their properties and viability of use in dosimetry. (author)

  12. Mechanical properties of rubberwood oriented strand lumber (OSL: The effect of strand length

    Directory of Open Access Journals (Sweden)

    Buhnnum Kyokong

    2005-09-01

    Full Text Available Effect of strand length on mechanical properties (tension, compression and bending of oriented strand lumber (OSL made of rubberwood (Hevea brasiliensis Muell. Arg. was reported. Three strand lengths of 50 mm, 100 mm, and 150 mm with 1 mm thickness and 15 mm width were used. The strands were mixed with 5% pMDI glue (weight basis in a tumble mixer. The OSL specimens were formed by hot pressing process of unidirectionally aligned strands. Average specific gravity and moisture content were 0.76 and 8.34%, respectively. Tension and compression tests were carried out for directions both parallel and perpendicular to grain while bending test was performed only in parallel direction. Ultimate stresses and moduli of elasticity were examined from the stress-strain curves. It was found that for the parallel-to-grain direction, the longer strand OSL gave higher strength. The role of the strand length did not appear for the direction normal to the grain. The relationship between the mechanical properties of OSL and strand length was well described by the modified Hankinson formula.

  13. OSL dating of sediments from Negro and Solimões rivers – Amazon, Brazil

    International Nuclear Information System (INIS)

    Fiore, M.; Soares, E.A.A.; Mittani, J.C.R.; Yee, M.; Tatumi, S.H.

    2014-01-01

    In this work, the OSL dating results of Quaternary fluvial deposits from the confluence of Negro and Solimões rivers were studied. The equivalent doses (D e ) of sediments were obtained using a Single Aliquot Regeneration (SAR) protocol. Statistic studies were made using frequency histogram, weighted histogram and Radial plot in order to analyze the D e fluctuations. Ages from 74.5 to 205 thousand of years (Pleistocene) were recorded. The gamma-ray spectroscopy was used to evaluate the natural radioisotopes concentrations of the samples and low concentrations were found with values between 0.64 and 3.71 ppm for 235 U and 238 U; 2.01–9.77 ppm for 232 Th; already, for 40 K, the concentration was negligible. The OSL dating of sediments has contributed to a better understanding of the evolution of Negro and Solimões rivers, in Amazon, Brazil. - Highlights: ► OSL dating of fluvial terraces from Amazon. ► SAR protocols applied to Amazon sediments dating. ► OSL dating of Solimão and Negro rivers sediments

  14. Retrospective radiation dosimetry using OSL of electronic components: Results of an inter-laboratory comparison

    International Nuclear Information System (INIS)

    Bassinet, C.; Woda, C.; Bortolin, E.; Della Monaca, S.; Fattibene, P.; Quattrini, M.C.; Bulanek, B.; Ekendahl, D.; Burbidge, C.I.; Cauwels, V.; Kouroukla, E.; Geber-Bergstrand, T.; Mrozik, A.; Marczewska, B.; Bilski, P.; Sholom, S.; McKeever, S.W.S.; Smith, R.W.; Veronese, I.

    2014-01-01

    In the framework of the EU-FP7 MULTIBIODOSE project, two protocols using OSL of resistors removed from the circuit board of mobile phones were developed with the aim to use the resistors as fortuitous dosimeters in the event of a large scale radiological accident. This paper presents the results of an inter-laboratory comparison carried out under the umbrella of EURADOS. The two aims of this exercise were the validation of the MULTIBIODOSE protocols by a large number of laboratories and the dissemination of the method with the objective of preparing the basis for a network that could increase Europe's response capacity in the case of a mass casualty radiological emergency. Twelve institutes from eleven European countries and one institute from the USA, with various degrees of expertise in OSL dosimetry, took part in the OSL inter-laboratory comparison. Generally, a good agreement within uncertainties was observed between estimated and nominal doses. - Highlights: • Resistors in mobile phones could function as reliable fortuitous dosimeters in case of a large scale radiological accident. • Two OSL protocols were validated by an inter-laboratory comparison. • It is feasible to set up a network of laboratories so as to increase the measurement capacity

  15. LM-OSL from single grains of quartz: A preliminary study

    DEFF Research Database (Denmark)

    Bulur, E.; Duller, G.A.T.; Solongo, S.

    2002-01-01

    the easy-to-bleach component, those with only the hard-to-bleach component, and those exhibiting all components. The results of this preliminary study show that LM-OSL experiments carried out at the single grain level may give important insights into the luminescence properties observed when viewing...

  16. TL/OSL ages from Salto Formation (Uruguay)tectonic, climatic and environmental considerations

    International Nuclear Information System (INIS)

    Ubilla, M.; Veroslavsky, G.

    2004-01-01

    TL/OSL ages from Salto Formation based on two sandy samples collected at Salto City and Route 3 (Boycua Creek) are provided: 986±100 ky (LVD-948) and 830±95 ky (LVD-949) respectively. Both support a Pleistocene age for Salto Formation, approximately late early/early middle Pleistocene. Neotectonic and climatic processes are also discussed [es

  17. Application of the OSL dosimetry technique in the identification of irradiated foods, such as condiments and spices

    International Nuclear Information System (INIS)

    Silva, Catherine C.O.; Alencar, Marcus A.V. de

    2013-01-01

    The use of ionizing radiation in food preservation is considered a well-established technique, so many countries, including Brazil, now allow the use of irradiated foods. Many methods have been tested for dosimetry and identification of irradiated foods including thermoluminescence, electron paramagnetic resonance, and others based on microbiological changes and in viscosity, and which requires a sample processing. The technique of optically stimulated luminescence (OSL) presents an advantage over other methods mentioned: The samples may be used without the need for a prior processing. This work aims to study the OSL properties of condiments and spices irradiated, in order to verify the possibility of the application of the OSL technique in identifying and dosimetry of irradiated foods. The samples used were of four kinds of spices: cumin, oregano, white pepper and black pepper. All samples were subjected to gamma irradiation from a Co-60 source with dose values of kerma in air of 100 Gy to 35 kGy. The samples of cumin presents the OSL signal, however, is only possible to identify whether the condiment was irradiated or not. The sample of oregano also presents the OSL signal, and for this condiment is possible to identify addition to its irradiation, the value of dose. The black pepper and white pepper samples don't presents the OSL signal. The results obtained in this study indicate the possibility of using the OSL technique for the identification and dosimetry of irradiated foods. (author)

  18. Pure thermal sensitisation and pre-dose effect of OSL in both unfired and annealed quartz samples

    Energy Technology Data Exchange (ETDEWEB)

    Oniya, Ebenezer O., E-mail: ebenezer.oniya@aaua.edu.ng [Physics and Electronics Department, Adekunle Ajasin University, 342111 Akungba Akoko (Nigeria); Polymeris, George S. [Institute of Nuclear Sciences, Ankara University, Beşevler 06100, Ankara (Turkey); Jibiri, Nnamdi N. [Department of Physics, University of Ibadan, Ibadan (Nigeria); Tsirliganis, Nestor C. [Department of Archaeometry and Physicochemical Measurements, R.C. ‘Athena’, P.O. Box 159, Kimmeria University Campus, 67100 Xanthi (Greece); Babalola, Israel A. [Department of Physics, University of Ibadan, Ibadan (Nigeria); Kitis, George [Nuclear Physics Laboratory, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2017-06-01

    The sensitisation of quartz has attracted much attention since its thorough understanding is important in luminescence studies and dating applications. The present investigation examines the influence of pure thermal activation and predose treatments on the sensitisation of different components of linearly modulated optically stimulated luminescence (LM-OSL) measured at room temperature (RT) thereby eliminating undesired thermal quenching effects. Annealed and unfired quartz samples from Nigeria were used. The OSL measurements were carried out using an automated RISØTL/OSL reader (model-TL/OSL–DA–15). A new approach was adopted to match each of the resolved components of the RT-LM-OSL to respective thermoluminescence (TL) peaks that share the same electron trap and recombination centers. Pure thermal activation and pre-dose treatments respectively affect the sensitisation of all the components of the RT-LM-OSL in a similar manner as the one reported for the 110 °C TL peak but without thermal quenching contributions. Component C4 in annealed samples that was identified to share the same electron trap and recombination centers with the 110 °C TL peak was also proved appropriate for RT-LM-OSL, instead of the initial part of the continuous wave (CW) OSL signal, thus the methods can serve as complementary dating methods.

  19. Pure thermal sensitisation and pre-dose effect of OSL in both unfired and annealed quartz samples

    International Nuclear Information System (INIS)

    Oniya, Ebenezer O.; Polymeris, George S.; Jibiri, Nnamdi N.; Tsirliganis, Nestor C.; Babalola, Israel A.; Kitis, George

    2017-01-01

    The sensitisation of quartz has attracted much attention since its thorough understanding is important in luminescence studies and dating applications. The present investigation examines the influence of pure thermal activation and predose treatments on the sensitisation of different components of linearly modulated optically stimulated luminescence (LM-OSL) measured at room temperature (RT) thereby eliminating undesired thermal quenching effects. Annealed and unfired quartz samples from Nigeria were used. The OSL measurements were carried out using an automated RISØTL/OSL reader (model-TL/OSL–DA–15). A new approach was adopted to match each of the resolved components of the RT-LM-OSL to respective thermoluminescence (TL) peaks that share the same electron trap and recombination centers. Pure thermal activation and pre-dose treatments respectively affect the sensitisation of all the components of the RT-LM-OSL in a similar manner as the one reported for the 110 °C TL peak but without thermal quenching contributions. Component C4 in annealed samples that was identified to share the same electron trap and recombination centers with the 110 °C TL peak was also proved appropriate for RT-LM-OSL, instead of the initial part of the continuous wave (CW) OSL signal, thus the methods can serve as complementary dating methods.

  20. Pulse and integral optically stimulated luminescence (OSL). Similarities and dissimilarities to thermoluminescence (TL) dose dependence and dose-rate effects

    International Nuclear Information System (INIS)

    Chen, R.; Leung, P.L.

    2000-01-01

    Optically stimulated luminescence (OSL) and thermoluminescence (Tl) are two possible methods to monitor the absorbed radiation in solid samples, and therefore are utilized for dosimetry. For this application, two properties are desirable, namely, linear dose dependence of the measured quantity and dose-rate independence. For Tl, different kinds of super linear dose dependence have been reported in the literature in different materials, and in some cases, dose-rate dependence has also been found. These have been explained as being the result of competition. In OSL, some recent works reported on super linear dose dependence in annealed samples. In the present work, we explain the possible occurrence of these phenomena in OSL by solving numerically the relevant rate equations governing the process during irradiation, relaxation and read-out (heating or light stimulation). The results show that for short pulse OSL, quadratic dose dependence can be expected when only one trapping state and one kind of recombination center are involved and when the excitation starts with empty traps and centers. With the short pulse OSL, the calculation also reveals a possible dose-rate effect. Under the same circumstances, the area under the OSL curve depends linearly on the dose. The dependence of the whole area under the OSL curve on the dose is shown to be super linear when a disconnected trapping state or radiationless center take part in the process. Also, dose-rate effect can be expected in these cases, although no experimental effect of this sort has been reported so far. In pulse OSL, the analogy is made between the measured intensity and the initial rise range of non-first order Tl, whereas for the total area OSL, there is a nearly full analogy with the dose behavior of the Tl maximum. (Author)

  1. TL and OSL studies on undoped diamond films grown by hot filament chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Soni, Anuj, E-mail: anujsoni.phy@gmail.com [Radiological Physics and Advisory Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Choudhary, R.K. [Materials Processing Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Polymeris, G.S. [Ankara University, Institute of Nuclear Sciences (Turkey); Mishra, D.R. [Radiological Physics and Advisory Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Mishra, P. [Materials Processing Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Kulkarni, M.S. [Radiation Safety Systems Division, Bhabha Atomic Research Center, Mumbai 400 085 (India)

    2016-09-15

    In this work, approximately 0.5 µm thick diamond films were grown on a silicon substrate by hot filament chemical vapour deposition (HFCVD) method in a gas mixture of hydrogen and methane. The batch to batch reproducibility of the sample using this technique was found to be very good. The obtained film was characterized by micro laser Raman spectroscopy (MLRS), grazing incidence X-ray diffractometry (GIXRD), scanning electron microscopy (SEM) and atomic force miscroscopy (AFM) techniques. MLRS and GIXRD results confirmed the formation of diamond whereas SEM and AFM analyses indicated uniform morphology of the film with an average grain size of 200 nm. The deposited film was studied for ionizing radiation dosimetry applications using the thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques after irradiating the film by a calibrated 5 mCi, {sup 90}Sr/{sup 90}Y beta source. In the TL measurement, for a heating rate of 4 K/s, broad glow curve was obtained which was deconvoluted into seven TL peaks. The integrated TL counts were found to vary linearly with increasing the radiation dose up to 10 kGy. The characteristic TL output seen in the temperature range 200–300 °C, may be considered good for thermal stability of the film and it could also avoid TL fading during storage and non-interference of any black body radiation during the measurement. However, in comparison to TL output, the OSL response for 470 nm LED stimulation was found to be lesser. The CW–OSL decay curve has shown two components contributing to the OSL signal, having photoionization cross-section 1.5×10{sup −18} and 5.2×10{sup −19} cm{sup 2} respectively. The studies have revealed the possibility of using diamond film for high dose radiation dosimetry with TL/OSL method.

  2. Tl and OSL dosimetry of diamond films CVD pure and unpurified with boron-carbon

    International Nuclear Information System (INIS)

    Melendrez, R.; Pedroza M, M.; Chernov, V.; Ochoa N, J.D.; Bernal, R.; Barboza F, M.; Castaneda, B.; Goncalves, J.A.N.; Sandonato, G.M.; Cruz Z, E.; Preciado F, S.; Cruz V, C.; Brown, F.; Schreck, M.

    2004-01-01

    The diamond is a material that possesses extreme physical properties, such as its hardness to the radiation, its low chemical reactivity besides its equivalence to the human tissue, which qualify him as an ideal material for radiation dosimetry. In this work, it was studied the thermal and optically stimulated response (Tl and OSL) of polycrystalline diamond films grown by the technique of CVD pure and contaminated with Boron-carbon (B/C) with the intention of characterizing their efficiency like a dosemeter for radiation in a range of 0 - 3000 Gy. For the case of the films without impurities, the Tl curve presents four main peaks, two of them in an interval of temperatures of 150-200 C and other two additional around of 250-400 C. The dependence of the response of integrated Tl and that of OSL always maintained a lineal relationship with the exhibition dose up to 100 Gy. The behavior of the films contaminated with B/C (2000 - 20000 ppm) was established through experiments that involved the signal of OSL and their relationship with the Tl response. It was found that this processes are correlated, since the electrons caught in the traps of low temperature (50 - 250 C) of the Tl they are the electrons that recombining with more probability to provide the signal of OSL. According to these results it is possible to propose the diamond films as a good candidate for dosimetry to, using the traditional technique of Tl so much as well as the but recent of OSL. (Author)

  3. Fiber optic based OSL set up for online and offline measurements of dose due to ionizing radiation

    International Nuclear Information System (INIS)

    Rawat, N.S.; Kulkarni, M.S.; Upadhyay, B.N.; Srikanth, G.; Bindra, K.S.; Oak, S.M.

    2016-01-01

    An optic-fiber dosimetry system based on optically stimulated luminescence (OSL) and radio-luminescence (RL) from Al_2O_3 : C single-crystal (detector) was designed and developed. The set up is intended to measure dose and dose rates at various radiological installations. The Al_2O_3:C single crystal (from Landaeur Inc. USA) was coupled to a fiber optic delivery system and OSL from the detector is stimulated via the optical fiber cable using light from a Nd:YAG laser. OSL and RL signals are later used to predict cumulative dose and dose rates using "6"0Co gamma source. (author)

  4. TL and OSL studies on lithium borate single crystals doped with Cu and Ag

    International Nuclear Information System (INIS)

    Rawat, N.S.; Kulkarni, M.S.; Tyagi, M.; Ratna, P.; Mishra, D.R.; Singh, S.G.; Tiwari, B.; Soni, A.; Gadkari, S.C.; Gupta, S.K.

    2012-01-01

    Lithium borate (LBO) single crystals doped with Cu and Ag (0.25 mol% each) (Li 2 B 4 O 7 :Cu,Ag) are grown by the Czochralski method. The thermoluminescence readout on Li 2 B 4 O 7 :Cu,Ag crystals showed three glow peaks at∼375, 441 and 516 K for the heating rate of 1 K/s. The thermoluminescence sensitivity of the grown Li 2 B 4 O 7 :Cu,Ag single crystals is found to be 5 times TLD-100 and a linear dose response in the range 1 mGy to 1 kGy. The glow curve deconvolution reveals nearly first order kinetics for all the three peaks with trap depths 0.77, 1.25 and 1.34 eV respectively and corresponding frequency factors 1.6×10 9 , 1.3×10 13 and 6.8×10 11 s −1 . The continuous wave optically stimulated luminescence (CW-OSL) measurements were performed on the LBO:Cu,Ag single crystals using blue light stimulation. The traps responsible for the three thermoluminescence peaks in Li 2 B 4 O 7 :Cu,Ag are found to be OSL sensitive. The qualitative correlation between TL peaks and CW-OSL response is established. The photoluminescence studies show that in case of co-doping of Ag in LBO:Cu the emission at 370 nm in Cu states dominates over the transitions in Ag states implying doping of Ag plays a role as sensitizer when co-doped with Cu and increases overall emission. - Highlights: ► Growth of crack free single crystals of Li2B4O7 :Cu and Ag. ► Study of TL and OSL parameters for Li2B4O7 :Cu and Ag. ► Correlation of OSL with TL peaks. ► Optimization of OSL readout time with respect to residual TL.

  5. A comparison of single and multiple aliquot TT-OSL data sets for sand-sized quartz from the Arabian Peninsula

    International Nuclear Information System (INIS)

    Rosenberg, T.M.; Preusser, F.; Wintle, A.G.

    2011-01-01

    The quartz OSL signal from dune sands from Saudi Arabia and Oman start to saturate at doses of about 100 Gy. In order to try to date dune sands with greater expected doses, a previously published, single-aliquot, regenerative-dose protocol (SAR) for thermally-transferred optically stimulated luminescence (TT-OSL) was tested. Dose recovery tests, recycling and recuperation ratios showed robust functioning and dose response curves demonstrated the potential to extend the dose range to beyond 600 Gy. Multiple aliquot additive dose (MAAD) TT-OSL protocols were used to test for sensitivity changes in the SAR TT-OSL protocol up to doses of 1200 Gy. A strong dose dependent deviation of the SAR TT-OSL relative to the MAAD TT-OSL dose response is observed. Comparison of the TT-OSL and OSL sensitivity data obtained from the MAAD and SAR data sets shows a lack of proportionality between TT-OSL and OSL for the SAR data which will result in a problem when SAR dose response curves are constructed using many regeneration points with doses above 300 Gy.

  6. Detection of sub micro Gray dose levels using OSL phosphor LiMgPO_4:Tb,B

    International Nuclear Information System (INIS)

    Rawat, N.S.; Dhabekar, Bhushan; Muthe, K.P.; Koul, D.K.; Datta, D.

    2017-01-01

    Highlights: • LiMgPO4:Tb,B has been studied and shown to possesses minimum measurable dose (MMD) in sub micro Gray region. • MMD as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm"2 has been achieved. • The OSL measurements for low doses has strengthened and validated this claim. • OSL spectrum shows several emission peaks and the prominent peak around 380 nm. - Abstract: Detection of sub micro Gray doses finds application in personnel and environmental monitoring, and nuclear forensics. Recently developed LiMgPO_4:Tb,B (LMP) is highly sensitive Optically Stimulated Luminescence (OSL) phosphor with excellent dosimetric properties. The OSL emission spectrum of LMP consists of several peaks attributed to characteristic Tb"3"+ emission. The OSL emission peak at 380 nm is favorable for bi-alkali PMT used in RISO reader system. It is demonstrated that significant improvement in dose detection threshold can be realized for LMP by optimization of continuous wave (CW–) OSL parameters like stimulation intensity and readout time. The minimum measurable dose (MMD) as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm"2 has been achieved using this phosphor. The recommendations for choice of parameters for personnel and environmental monitoring are also discussed.

  7. Detection of sub micro Gray dose levels using OSL phosphor LiMgPO{sub 4}:Tb,B

    Energy Technology Data Exchange (ETDEWEB)

    Rawat, N.S., E-mail: naru@barc.gov.in [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Dhabekar, Bhushan [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Muthe, K.P. [Technical Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Koul, D.K.; Datta, D. [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    2017-04-15

    Highlights: • LiMgPO4:Tb,B has been studied and shown to possesses minimum measurable dose (MMD) in sub micro Gray region. • MMD as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm{sup 2} has been achieved. • The OSL measurements for low doses has strengthened and validated this claim. • OSL spectrum shows several emission peaks and the prominent peak around 380 nm. - Abstract: Detection of sub micro Gray doses finds application in personnel and environmental monitoring, and nuclear forensics. Recently developed LiMgPO{sub 4}:Tb,B (LMP) is highly sensitive Optically Stimulated Luminescence (OSL) phosphor with excellent dosimetric properties. The OSL emission spectrum of LMP consists of several peaks attributed to characteristic Tb{sup 3+} emission. The OSL emission peak at 380 nm is favorable for bi-alkali PMT used in RISO reader system. It is demonstrated that significant improvement in dose detection threshold can be realized for LMP by optimization of continuous wave (CW–) OSL parameters like stimulation intensity and readout time. The minimum measurable dose (MMD) as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm{sup 2} has been achieved using this phosphor. The recommendations for choice of parameters for personnel and environmental monitoring are also discussed.

  8. Quartz OSL dating of late Holocene beach ridges from the Magdalen Islands (Quebec, Canada)

    DEFF Research Database (Denmark)

    Remillard, A.M.; Buylaert, Jan-Pieter; Murray, Andrew

    2015-01-01

    Quartz optically stimulated luminescence (OSL) dating has been applied to sandy beach ridge systems from the Magdalen Islands in the center of the Gulf of St. Lawrence (Quebec, Canada) to provide the first chronological framework for these features. Nineteen beach ridges (22 samples) from four......). The OSL ages indicate that the ridges were built between 2.6 ± 0.2 ka and 0.40 ± 0.10 ka, i.e. during a period of sea level rise. This rise eroded adjacent sandstone cliffs, which contributed a significant sediment supply to the littoral drift and beaches. Some low-lying coasts in the archipelago...... great potential in this area, and is an appropriate method for establishing precise chronologies for coastal sediments in this region of the Gulf of St. Lawrence. © 2015 Elsevier B.V. All rights reserved....

  9. TL, OSL and C-14 dating results of the sediments and bricks from mummified nuns' grave

    International Nuclear Information System (INIS)

    Tudela, Diego R.G.; Tatumi, Sonia H.; Yee, Marcio; Brito, Silvio L.M.

    2012-01-01

    This paper presents the results of TL and OSL dating of soil and fragments of bricks from a grave, which was occupied by two mummified nuns, found at 'Luz' Monastery, located in the state of Sao Paulo, Brazil. The TL and OSL ages were compared to C-14 dating ones obtained from bone collagens of the mummies. The majority of the ages is related to the eighteenth century. The gamma-ray spectroscopy was used to evaluate natural radioisotope concentrations in the samples, and by using these concentrations the annual dose rates, from 3.0 to 5.3 Gy/kyr, were obtained. Neutron activation analysis was performed and the radioisotope contents results are in agreement with those obtained by gamma-ray spectroscopy. The contents of U, Th and Ce elements were higher than those found in usual sediments. (author)

  10. Thermally assisted OSL from deep traps in Al2O3:C

    International Nuclear Information System (INIS)

    Polymeris, G.S.; Raptis, S.; Afouxenidis, D.; Tsirliganis, N.C.; Kitis, G.

    2010-01-01

    The present work suggests an alternative experimental method in order to not only measure the signal of the deep traps in Al 2 O 3 :C without heating the sample to temperatures greater than 500 o C, but also use this signal for high dose level dosimetry purposes as well. This method consists of photo transfer OSL measurements performed at elevated temperatures using the blue LEDs (470 nm, FWHM 20 nm) housed at commercial Riso TL/OSL systems, after the sample was previously heated up to 500 o C in order to empty its main TL dosimetric trap. The influence of this procedure on specific features such as glow curve shape and sensitivity of the main TL glow peak was also studied.

  11. SSDL Preparation for Implementation of the Use of OSL Dosimeters in Malaysia

    International Nuclear Information System (INIS)

    Sangau, J.K.; Taiman Kadni; Ahmad Bazlie Abdul Kadir

    2013-01-01

    Since the early 1980's, film badge has been widely used as a device of personal dose monitoring in Malaysia. Secondary Standard Dosimetry Laboratory (SSDL), as a service center for film badge has obtained the supply of personal monitoring film from Agfa Gevaert, Belgium every year. As the uses of film badge have some weaknesses, it has prompted SSDL to find an alternative dosimeter to replace the film badge. Based on the studies that have been conducted, SSDL has selected OSL dosimeter (Optically Stimulated Luminescent Dosimeter) to replace the film badge and is expected to be fully operational by middle of 2015. This paper aims to explain the selection of OSL dosimeter and planning carried out to ensure the success of their application in Malaysia. (author)

  12. Optically stimulated luminescence (OSL) as a chronometer for surface exposure dating

    DEFF Research Database (Denmark)

    Sohbati, Reza; Murray, Andrew S.; Chapot, Melissa S.

    2012-01-01

    We pioneer a technique of surface-exposure dating based upon the characteristic form of an optically stimulated luminescence (OSL) bleaching profile beneath a rock surface; this evolves as a function of depth and time. As a field illustration of this new method, the maximum age of a premier example...... exposure histories; one of these samples was exposed at the time of sampling and one was buried and no longer light exposed. A third sample is known to have been first exposed 80 years ago and was still exposed at the time of sampling. First, the OSL-depth profile of the known-age sample is modeled...... to estimate material-dependent and environmental parameters. These parameters are then used to fit the model to the corresponding data for the samples of unknown exposure history. From these fits we calculate that the buried sample was light exposed for similar to 700 years before burial and that the unburied...

  13. Two-dimensional chronostratigraphic modelling of OSL ages from recent beach-ridge deposits, SE Australia

    DEFF Research Database (Denmark)

    Tamura, Toru; Cunningham, Alastair C.; Oliver, Thomas S.N.

    2018-01-01

    Optically-stimulated luminesecne (OSL) dating, in concert with two-dimensional ground-penetrating radar (GPR) profiling, has contributed to significant advances in our understanding of beach-ridge systems and other sedimentary landforms in various settings. For recent beach-ridges, the good OSL...... samples may be larger than the difference in sample ages. Age inversions can be avoided, however, if the stratigraphic constraints are included in the age estimation process. Here, we create a custom Bayesian chronological model for a recent (..., for direct comparison with a GPR profile. The model includes a full ‘burial-dose model’ for each sample and a dose rate term with the modelled ages constrained by the vertical and shore-normal sample order. The modelled ages are visualized by plotting isochrones on the beach-ridge cross section...

  14. State of the art of solid state dosimetry; Estado da arte em dosimetria do estado solido

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Susana O., E-mail: sosouza@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil); Yamamoto, Takayoshi [Radioisotope Research Center, Osaka University (Japan); D' Errico, Francesco, E-mail: francesco.derrico@yale.edu [Yale University, School of Medicine, CT (United States)

    2014-07-01

    Passive solid-state detectors still dominate the personal dosimetry field. This article provides state of the art in this field and summarizes the most recent works presented on TL, OSL and RPL during the 17th International Conference on Solid State Dosimetry held in Recife in September 2013. The Article contains in particular the techniques Thermoluminescence (TL), Optically Stimulated Luminescence (OSL), radio photoluminescence (RPL). Thermoluminescence has the biggest advantage of the wide availability of commercial materials for dosimetry, and the nature tissue-equivalent of several of these materials. The limitation of the TL dosimetry presents fading luminance signal and the need for high temperatures to obtain the signal. The Optically Stimulated Luminescence has the advantages of high sensitivity, the possibility of multiple reading, while its limit is the need to use response compensating filters in addition to the high cost of equipment and dosimeters still restricted very few options trading . The radio photoluminescence has a reading that is completely non-destructive, but their dosimeters present lack of tissue-equivalent and a high cost. Presents the details of the techniques and the advantages and limitations of each of these will be discussed.

  15. Teflon pastille use in high dose dosimetry; Utilizacao de pastilhas de teflon em dosimetria de doses altas

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Maria Ines [Associacao Educacional Nove de Julho (UNINOVE), Sao Paulo, SP (Brazil); Caldas, Linda V.E., E-mail: miteixeira@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    This paper study the Teflon, which is used as aglomerant in the confection of dosimetric pastilles, for the viabilization of this material as high dose dosimeter. This paper used the OSL technique for the characterization of dosimetric properties of Teflon. The doses-response curve has been obtained for {sup 60}Co radiation between 100 Gy and 50 kGy, and the OSL answer reproducibility. The preliminary results shown that the Teflon is a material which can be used for high dose dosimetry

  16. BeO-OSL detectors for dose measurements in cell cultures

    International Nuclear Information System (INIS)

    Andreeff, M.; Freudenberg, R.; Kotzerke, J.; Sommer, D.; Reichelt, U.; Henniger, J.

    2009-01-01

    Aim: The absorbed dose is an important parameter in experiments involving irradiation of cells in vitro with unsealed radionuclides. Typically, this is estimated with a model calculation, although the results thus obtained cannot be verified. Generally used real-time measurement methods are not applicable in this setting. A new detector material with in vitro suitability is the subject of this work. Methods: Optically-stimulated luminescence (OSL) dosimeters based on beryllium oxide (BeO) were used for dose measurement in cell cultures exposed to unsealed radionuclides. Their qualitative properties (e. g. energy-dependent count rate sensitivity, fading, contamination by radioactive liquids) were determined and compared to the results of a Monte Carlo simulation (using AMOS software). OSL dosimeters were tested in common cell culture setups with a known geometry. Results: Dose reproducibility of the OSL dosimeters was ± 1.5%. Fading at room temperature was 0.07% per day. Dose loss (optically-stimulated deletion) under ambient lighting conditions was 0.5% per minute. The Monte Carlo simulation for the relative sensitivity at different beta energies provided corresponding results to those obtained with the OSL dosimeters. Dose profile measurements using a 6 well plate and 14 ml PP tube showed that the geometry of the cell culture vessel has a marked influence on dose distribution with 188 Re. Conclusion: A new dosimeter system was calibrated with β-emitters of different energy. It turned out as suitable for measuring dose in liquids. The dose profile measurements obtained are suitably precise to be used as a check against theoretical dose calculations. (orig.)

  17. OSL properties of three commonly available salt brands in India for its use in accident dosimetry

    Science.gov (United States)

    Singh, A. K.; Menon, S. N.; Kadam, S. Y.; Koul, D. K.; Datta, D.

    2018-03-01

    Thermally stimulated luminescence (TL) and Optically Stimulated Luminescence (OSL) characterization of three commonly available salt brands in India were undertaken for their application in accident dosimetry. The investigations showed that the luminescence properties differed to some extent with that reported in literature. Dosimetric properties of these salt samples showed that these can be useful in accident dosimetry. Based on the sensitization and fading behaviour of the samples a Single Aliquot Regenerative (SAR) protocol has been proposed for dose estimation.

  18. TL and OSL properties of Mn2+-doped MgGa2O4 phosphor

    Science.gov (United States)

    Luchechko, A.; Zhydachevskyy, Ya; Maraba, D.; Bulur, E.; Ubizskii, S.; Kravets, O.

    2018-04-01

    The oxide MgGa2O4 spinel ceramics doped with Mn2+ ions was synthesized by a solid-state reaction at 1200 °C in air. The activator concentration was equal 0.05 mol% of MnO. Phase purity of the synthesized samples was analyzed by X-ray diffraction technique. This spinel ceramics show efficient green emission in the range from 470 to 550 nm with a maximum at about 505 nm under UV or X-ray excitations, which is due to Mn2+ ions. MgGa2O4: Mn2+ exhibits intense thermoluminescence (TL) and optically stimulated luminescence (OSL) after influence of ionizing radiation. Are complex nature of the TL glow curves is associated with a significant number of structural defects that are responsible for the formation of shallow and deep electron traps. In this work, time-resolved OSL characteristics of the samples exposed to beta particles are reported for the first time. A light from green LED was used for optical stimulation. Obtained TL and OSL results suggest MgGa2O4:Mn2+ as perspective material for further research and possible application in radiation dosimetry.

  19. Dose rate dependence for different dosimeters and detectors: TLD, OSL, EBT films, and diamond detectors

    International Nuclear Information System (INIS)

    Karsch, L.; Beyreuther, E.; Burris-Mog, T.; Kraft, S.; Richter, C.; Zeil, K.; Pawelke, J.

    2012-01-01

    Purpose: The use of laser accelerators in radiation therapy can perhaps increase the low number of proton and ion therapy facilities in some years due to the low investment costs and small size. The laser-based acceleration technology leads to a very high peak dose rate of about 10 11 Gy/s. A first dosimetric task is the evaluation of dose rate dependence of clinical dosimeters and other detectors. Methods: The measurements were done at ELBE, a superconductive linear electron accelerator which generates electron pulses with 5 ps length at 20 MeV. The different dose rates are reached by adjusting the number of electrons in one beam pulse. Three clinical dosimeters (TLD, OSL, and EBT radiochromic films) were irradiated with four different dose rates and nearly the same dose. A faraday cup, an integrating current transformer, and an ionization chamber were used to control the particle flux on the dosimeters. Furthermore two diamond detectors were tested. Results: The dosimeters are dose rate independent up to 410 9 Gy/s within 2% (OSL and TLD) and up to 1510 9 Gy/s within 5% (EBT films). The diamond detectors show strong dose rate dependence. Conclusions: TLD, OSL dosimeters, and EBT films are suitable for pulsed beams with a very high pulse dose rate like laser accelerated particle beams.

  20. TL/OSL properties of natural schist for archaeological dating and retrospective dosimetry

    International Nuclear Information System (INIS)

    Afouxenidis, D.; Stefanaki, E.C.; Polymeris, G.S.; Sakalis, A.; Tsirliganis, N.C.; Kitis, G.

    2007-01-01

    Schist, a metamorphic rock composed largely of quartz and muscovite, has been used as a building stone through the centuries in many parts of the world. In ancient Greece, it was used in buildings and monuments (Knossos, Karthaia, etc). Basic TL and OSL properties of schist are studied in the present work to evaluate its potential use in archaeological dating and retrospective dosimetry. In particular, the optical stability, as well as the linearity of the TL and OSL signal were investigated for samples of natural schist obtained from a roofing slate. The results indicate that both signals are rapidly bleached when the sample is exposed to sunlight. An exposure of 1 min reduces the TL signal by 93%, the IRSL signal by 99% and the post-IR BSL signal by 90%. The dose response was found to be linear for a radiation dose at least up to 75 Gy for the TL and the IR OSL signal and at least up to 25 Gy for the post-IR BSL signal

  1. A method to acquire CT organ dose map using OSL dosimeters and ATOM anthropomorphic phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Da; Li, Xinhua; Liu, Bob [Division of Diagnostic Imaging Physics and Webster Center for Advanced Research and Education in Radiation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Gao, Yiming; Xu, X. George [Nuclear Engineering Program, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2013-08-15

    Purpose: To present the design and procedure of an experimental method for acquiring densely sampled organ dose map for CT applications, based on optically stimulated luminescence (OSL) dosimeters “nanoDots” and standard ATOM anthropomorphic phantoms; and to provide the results of applying the method—a dose data set with good statistics for the comparison with Monte Carlo simulation result in the future.Methods: A standard ATOM phantom has densely located holes (in 3 × 3 cm or 1.5 × 1.5 cm grids), which are too small (5 mm in diameter) to host many types of dosimeters, including the nanoDots. The authors modified the conventional way in which nanoDots are used, by removing the OSL disks from the holders before inserting them inside a standard ATOM phantom for dose measurements. The authors solved three technical difficulties introduced by this modification: (1) energy dependent dose calibration for raw OSL readings; (2) influence of the brief background exposure of OSL disks to dimmed room light; (3) correct pairing between the dose readings and measurement locations. The authors acquired 100 dose measurements at various positions in the phantom, which was scanned using a clinical chest protocol with both angular and z-axis tube current modulations.Results: Dose calibration was performed according to the beam qualities inside the phantom as determined from an established Monte Carlo model of the scanner. The influence of the brief exposure to dimmed room light was evaluated and deemed negligible. Pairing between the OSL readings and measurement locations was ensured by the experimental design. The organ doses measured for a routine adult chest scan protocol ranged from 9.4 to 18.8 mGy, depending on the composition, location, and surrounding anatomy of the organs. The dose distribution across different slices of the phantom strongly depended on the z-axis mA modulation. In the same slice, doses to the soft tissues other than the spinal cord demonstrated

  2. A method to acquire CT organ dose map using OSL dosimeters and ATOM anthropomorphic phantoms

    International Nuclear Information System (INIS)

    Zhang, Da; Li, Xinhua; Liu, Bob; Gao, Yiming; Xu, X. George

    2013-01-01

    Purpose: To present the design and procedure of an experimental method for acquiring densely sampled organ dose map for CT applications, based on optically stimulated luminescence (OSL) dosimeters “nanoDots” and standard ATOM anthropomorphic phantoms; and to provide the results of applying the method—a dose data set with good statistics for the comparison with Monte Carlo simulation result in the future.Methods: A standard ATOM phantom has densely located holes (in 3 × 3 cm or 1.5 × 1.5 cm grids), which are too small (5 mm in diameter) to host many types of dosimeters, including the nanoDots. The authors modified the conventional way in which nanoDots are used, by removing the OSL disks from the holders before inserting them inside a standard ATOM phantom for dose measurements. The authors solved three technical difficulties introduced by this modification: (1) energy dependent dose calibration for raw OSL readings; (2) influence of the brief background exposure of OSL disks to dimmed room light; (3) correct pairing between the dose readings and measurement locations. The authors acquired 100 dose measurements at various positions in the phantom, which was scanned using a clinical chest protocol with both angular and z-axis tube current modulations.Results: Dose calibration was performed according to the beam qualities inside the phantom as determined from an established Monte Carlo model of the scanner. The influence of the brief exposure to dimmed room light was evaluated and deemed negligible. Pairing between the OSL readings and measurement locations was ensured by the experimental design. The organ doses measured for a routine adult chest scan protocol ranged from 9.4 to 18.8 mGy, depending on the composition, location, and surrounding anatomy of the organs. The dose distribution across different slices of the phantom strongly depended on the z-axis mA modulation. In the same slice, doses to the soft tissues other than the spinal cord demonstrated

  3. The dependence of dose recovery experiments on the bleaching of natural quartz OSL using different light sources

    International Nuclear Information System (INIS)

    Choi, J.H.; Murray, A.S.; Cheong, C.-S.; Hong, S.C.

    2009-01-01

    In this paper, the dependence of dose recovery tests on the different bleaching light sources (blue-LEDs, solar simulator, natural sunlight) is investigated with a variety of sedimentary quartz samples, selected so that their OSL signals are dominated by the fast OSL component. We observed that when long solar simulator bleaching was applied, various known doses were underestimated in an SAR-based dose recovery test. However, when blue-LEDs and short solar simulator bleaching were used (10 s and 60 s) the known doses were accurately recovered. In repeated measurement of the OSL signals induced by the same regeneration and test dose, we observed a considerable increase in quartz OSL sensitivity during or after the first OSL measurement when long solar simulator bleaching was used; this seems to provide a possible explanation for the observed underestimation of the laboratory known doses. A series of experimental results using a sample from a modern aeolian dune surface shows that there are no subsequent sensitivity changes when the naturally zeroed samples are bleached with sunlight for long time. It seems that there is a dependence of the sensitivity change on the amount of dose administered before solar simulator bleaching and on the light intensity of solar simulator. When small doses were given to the naturally zeroed sample, the sensitivity change during or after the first OSL measurement was not significant. However, when a considerable amount of beta dose (∼4000 Gy) is administered to the sample, a clear sensitivity change during or after the first OSL measurement (∼20%) was observed. Such a sensitivity change was not observed when the bleaching light intensity of solar simulator was reduced by increasing the distance between samples and the UV lamp. Our results show that, at least for the samples described here, the outcomes of dose recovery experiments are dependent on the bleaching conditions.

  4. The correlation of fast OSL component with the TL peak at 3250C in quartz of various origins

    International Nuclear Information System (INIS)

    Kitis, G.; Kiyak, N.; Polymeris, G.S.; Tsirliganis, N.C.

    2010-01-01

    The fast component of the optically stimulated luminescence (OSL) signal in quartz is the basic tool for the optical dating. Its relation with the thermoluminescence (TL) glow-peak at about 325 deg. C is well established for naturally irradiated quartz. This relationship is also an important part of a general model for quartz on which many theoretical simulations of various OSL experimental results have been based. In the present work this relationship is systematically investigated in nine quartz samples of different origin. The linearly modulated OSL (LM-OSL) curves of all quartz samples for stimulation time less than 50 s consists of two components discriminated easily by a computerized curve deconvolution (CCD) analysis. By comparing the un-bleached to the respective bleached TL glow-curve, it is found that the system of these two fast OSL components is directly related with only a small portion of the electron traps responsible for the TL glow-peaks in the temperature region 200-400 0 C. By increasing the stimulation times, besides the two fast components, the medium and the slow components are also obtained. The medium and slow components are clearly related with the main body of the electron traps responsible for TL glow-peaks in the same temperature region 200-400 0 C. Despite their different origin all quartz samples show an appreciable homogeneity concerning the number and time position of the individual components, whereas, the relative TL/OSL intensities vary strongly from sample to sample with the integrated TL intensity being generally much less than the integrated OSL intensity.

  5. The fast ratio: A rapid measure for testing the dominance of the fast component in the initial OSL signal from quartz

    International Nuclear Information System (INIS)

    Durcan, Julie A.; Duller, Geoff A.T.

    2011-01-01

    The signal from the fast component is usually considered preferable for quartz optically stimulated luminescence (OSL) dating, however its presence in a continuous wave (CW) OSL signal is often assumed, rather than verified. This paper presents an objective measure (termed the fast ratio) for testing the dominance of the fast component in the initial part of a quartz OSL signal. The ratio is based upon the photo ionisation cross-sections of the fast and medium components and the power of the measurement equipment used to record the OSL signal, and it compares parts of the OSL signal selected to represent the fast and medium components. The ability of the fast ratio to distinguish between samples whose CW-OSL signal is dominated by the fast and non-fast components is demonstrated by comparing the fast ratio with the contribution of the fast component calculated from curve deconvolution of measured OSL signals and from simulated data. The ratio offers a rapid method for screening a large number of OSL signals obtained for individual equivalent dose estimates, it can be calculated and applied as easily as other routine screening methods, and is transferrable between different aliquots, samples and measurement equipment. - Highlights: → Fast ratio is a measure which tests dominance of fast component in quartz OSL signals. → A fast ratio above 20 implies a CW-OSL signal is dominated by fast component. → Fast ratio can be easily and rapidly applied to a large number of OSL signals. → Uses include signal comparison, data screening, identify need for further analysis.

  6. Quartz OSL Dating of the loess deposit in the eastern Tibetan Plateau and its environment implications since the Last Glaciation

    Science.gov (United States)

    Yang, S.; Cheng, T.; Liu, W.; Fang, X.

    2017-12-01

    Loess deposit is widespread in the Chuanxi Plateau, the eastern Tibetan Plateau, which is a critical archive for understanding the aeolian process, the evolution of the westerly and the environment changes on the Plateau. Previous studies have shown its aeolian origin, and mainly transported by wind from the western part of the Tibetan Plateau. However, the aeolian processes of the loess and its environment implications are not well understood mainly due to lack of detailed age controls. We carry out a combined quartz optically stimulated luminescence (OSL) dating and accelerator mass spectrometry radiocarbon dating (AMS 14-C) for the loess deposits in Garzê and Jinchuan. The results indicate that the quartz OSL dating can provide reliable age controls for the loess-paleosol sequences from the Chuanxi Plateau, showing the potential of OSL to date loess in the high altitude region. The results indicate that the OSL ages are in agreement with the observed stratigraphy in the field. The constructed OSL and AMS 14-C chronology of the Garzê loess reveals that the widespread loess in Ganzi Region deposited since the Last Glacial. The dust accumulation is rapid during marine isotope stage (MIS) 3 and 2, and a relative low accumulation rate in the Holocene, which may related with the desertification processes of the inner Tibetan Plateau.

  7. Application of pulsed OSL to the separation of the luminescence components from a mixed quartz/feldspar sample

    International Nuclear Information System (INIS)

    Denby, P.M.; Botter-Jensen, L.; Murray, A.S.; Thomsen, K.J.; Moska, P.

    2006-01-01

    It is known that the pulsed optically stimulated luminescence (OSL) characteristics of quartz and feldspars are very different. These differences can be used to preferentially discriminate against the feldspar signal in mixed quartz-bar feldspar mineral assemblages, or in separated quartz contaminated with a feldspar signal. We have developed instrumentation for the study of high-speed pulse stimulated OSL. Our system uses the standard blue/IR LED stimulation unit of a Riso reader (allowing stimulation pulses down to 1-2μs duration) and can thus be applied to the routine analysis of samples. Using this stimulation source, and high-speed photon timing, the OSL yield can be monitored throughout the pulsing cycle and subsequent OSL decay. It is found that the total photon yield per unit stimulation power in pulsed mode is, for quartz, twice and, for feldspar, nearly four times, that in continuous wave mode. Observation of this OSL signal, between stimulation pulses, is seen to be characteristic of the mineral being examined, and has been used to preferentially discriminate against feldspar contamination in a mixed quartz/feldspar sample. Simple implementation of this technique by gating the counting period, so that counts are only accumulated during a windowed period, reduces the feldspar signal to 1.6% of its original value relative to that of the quartz

  8. A fiber-dosimetry method based on OSL from Al2O3:C for radiotherapy applications

    International Nuclear Information System (INIS)

    Gaza, R.; McKeever, S.W.S.; Akselrod, M.S.; Akselrod, A.; Underwood, T.; Yoder, C.; Andersen, C.E.; Aznar, M.C.; Marckmann, C.J.; Boetter-Jensen, L.

    2004-01-01

    We describe a high-sensitivity, fiber-optic dosimetry system based on optically stimulated luminescence (OSL) and radioluminescence from Al 2 O 3 :C single-crystal fibers (detectors). The detectors are coupled to a fiber optic delivery system and OSL from the detector is stimulated via the optical fiber cable using light from a Nd:YAG laser. The OSL is guided back along the same fiber and is detected by a photomultiplier tube. The Al 2 O 3 :C detectors are small and demonstrate high sensitivity with a large signal-to-noise ratio. We describe two modes of operation of the system and discuss algorithms that provide accurate estimation of dose rate and integrated dose in near real time. The system is free from magnetic and electrical interference, and is designed for use in several forms of radiotherapy, including in vitro brachytherapy source calibration, and in vivo dosimetry during patient treatment

  9. Correlation between TL and OSL signals in KMgF3:Ce3+: Bleaching study of individual glow-peaks

    International Nuclear Information System (INIS)

    Dallas, G.I.; Polymeris, G.S.; Afouxenidis, D.; Tsirliganis, N.C.; Tsagas, N.F.; Kitis, G.

    2010-01-01

    KMgF 3 :Ce 3+ is an ultra sensitive Thermoluminescence (TL) material with a complex TL and OSL glow-curve structure. The aim of the present work is to attempt a one-to-one correspondence between specific TL glow-peaks and OSL components in KMgF 3 :Ce 3+ . The correlation study involves the deconvolution of the TL curves and the estimation of the bleaching decay constants for individual glow-peaks followed by the deconvolution of the LM-OSL curve using the estimated decay constants. It was found that the bleaching of each individual glow-peak takes place in three different rates; namely in a fast, medium and slow rate.

  10. TL-OSL study of Li{sub 3}PO{sub 4}: Mg, Cu phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Rahangdale, S. R., E-mail: sachin.rahangdale1@gmail.com; Wankhede, S. P. [Department of Physics, K.D.K.College of Engineering, Nagpur (India); Dhabekar, B. S. [RPAD, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Palikundwar, U. A.; Moharil, S. V. [Department of Physics, RTM Nagpur University, Nagpur, 440010 (India)

    2015-08-28

    In the present work, we report the thermoluminescence and optically stimulated luminescence properties of Mg and Cu doped Li{sub 3}PO{sub 4} phosphor. The phosphor was synthesized by precipitation method. The thermoluminescence dosimetric peak temperature for the phosphor varies with concentrations of Mg and Cu. Li{sub 3}PO{sub 4} shows good response to 470nm optical stimulation. The OSL sensitivity of the phosphor is approximately 12 times than that of standard Lithium magnesium phosphate. This study may help to develop this material for the application in real time dosimetry using optically stimulated luminescence.

  11. Constraining Middle Pleistocene Glaciations in Birmingham, England; Using Optical Stimulated Luminescence (OSL) Dating.

    Science.gov (United States)

    Gibson, S. M.; Gibbard, P. L.; Bateman, M. D.; Boreham, S.

    2014-12-01

    Birmingham is built on a complex sequence of Middle Pleistocene sediments, representing at least three lowland glaciations (MIS12, MIS6, and MIS2). British Geological Survey mapping accounts 75% of the land mass as Quaternary deposits; predominantly glacial-sandy tills, glacial-fluvial sands, clays and organic silts and peats. Understanding the age of fluvial-glacial outwash, related to specific glaciations, is critical in establishing a Geochronology of Birmingham. Shotton (1953) found a series of Middle Pleistocene glacial sediments, termed the Wolstonian, intermediate in age between MIS11 and MIS5e Interglacial's. Uncertainty surrounding the relation to East Anglian sequences developed by Rose (1987) implies Birmingham sequences should be referred to MIS12. Despite this, younger Middle Pleistocene glacial sequences occur in Birmingham, yet uncertainty has deepened over our understanding of the complex, inaccessible sediments, especially as deposits have similar extent with MIS2 sequences. Five Optical Stimulated Luminescence (OSL) dates from three sites around Birmingham have been sampled. East of Birmingham, ice advanced from the Irish Sea and later the North East. In Wolston, a sample of outwash sand, associated with the Thurssington Till, is dated. In Meriden, two samples of outwash sands, associated with a distal Oadby Till, are dated. West of Birmingham, ice advanced from the Welsh Ice Sheet. In Seisdon, two samples of an Esker and outwash sand, associated with a Ridgeacre Till, are dated. Correlation of OSL dates provide an important constraint on understanding the history of Birmingham. Using GSI3D modeling to correlate geochronology and sedimentology, the significance of OSL dating can be understood within the complex sequences (and regional stratigraphy), complimented by Cosmogenic and Palynology dates taken in South West and North East. OSL dating on Birmingham's outwash sands, deposited by extensive repeated Middle Pleistocene glaciations, asserts the

  12. TL, OSL and C-14 dating results of the sediments and bricks from mummified nuns' grave

    Directory of Open Access Journals (Sweden)

    Diego R.G. Tudela

    2012-06-01

    Full Text Available This paper presents the results of TL and OSL dating of soil and fragments of bricks from a grave, which was occupied by two mummified nuns, found at "Luz" Monastery, located in the state of São Paulo, Brazil. The TL and OSL ages were compared to C-14 dating ones obtained from bone collagens of the mummies. The majority of the ages is related to the eighteenth century. The gamma-ray spectroscopy was used to evaluate natural radioisotope concentrations in the samples, and by using these concentrations the annual dose rates, from 3.0 to 5.3 Gy/kyr, were obtained. Neutron activation analysis was performed and the radioisotope contents results are in agreement with those obtained by gamma-ray spectroscopy. The contents of U, Th and Ce elements were higher than those found in usual sediments.Este artigo apresenta os resultados de datação por TL e OSL de solos, e fragmentos de tijolos de um túmulo, que foi ocupado por duas freiras mumificadas encontradas no Mosteiro da "Luz", localizado no Estado de São Paulo, Brasil. As idades encontradas por TL e OSL foram comparadas às obtidas a partir de C-14 dos colágenos contidos em amostras de osso das múmias. A maioria das idades obtidas são do século XVIII. A espectroscopia de radiação-gama foi utilizada para avaliar concentrações de radioisótopos naturais nas amostras e para calcular as taxas de dose anual que resultaram em 3,0 a 5,3 Gy/kano. As concentrações radioativas são próximas daquelas obtidas através de Análise por Ativação de Nêutrons. Os conteúdos de elementos U, Th e Ce são superiores aos encontrados na maioria dos sedimentos.

  13. SU-E-T-592: OSL Response of Al2O3:C Detectors Exposed to Therapeutic Proton Beams

    Energy Technology Data Exchange (ETDEWEB)

    Granville, DA [Carleton Laboratory for Radiotherapy Physics, Carleton University, Ottawa, ON (Canada); Flint, DB; Sawakuchi, GO [The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: To characterize the response of Al{sub 2}O{sub 3}:C optically stimulated luminescence (OSL) detectors (OSLDs) exposed to therapeutic proton beams of differing beam quality. Methods: We prepared Al{sub 2}O{sub 3}:C OSLDs from the same material as commercially available nanoDot dosimeters (Landauer, Inc). We irradiated the OSLDs in modulated proton beams of varying quality, as defined by the residual range. An absorbed dose to water of 0.2 Gy was delivered to all OSLDs with the residual range values varying from 0.5 to 23.5 cm (average LET in water from ∼0.5 to 2.5 keV/µm). To investigate the beam quality dependence of different emission bands within the OSL spectrum, we performed OSLD readouts using both continuous-wave stimulation (CW-OSL) and pulsed stimulation (P-OSL) with two sets of optical filters (Hoya U-340 and Kopp 5113). For all readout modes, the relative absorbed dose sensitivity (S{sub rel}) for each beam quality was calculated using OSLDs irradiated in a 6 MV photon beam as a reference. Results: We found that the relative absorbed dose sensitivity was highly dependent on both readout mode and integration time of the OSL signal. For CW-OSL signals containing only the blue emission band, S{sub rel} was between 0.85 and 0.94 for 1 s readouts and between 0.82 and 0.93 for 10 s readouts. Similarly, for P-OSL readouts containing only the blue emission band S{sub rel} ranged from 0.86 to 0.91, and 0.82 to 0.93 for 1 s and 10 s readouts, respectively. For OSLD signals containing only the UV emission band, S{sub rel} ranged from 1.00 to 1.46, and 0.97 to 1.30 for P-OSL readouts of 1 s and 10 s, respectively. Conclusion: For measurements of absorbed dose using Al{sub 2}O{sub 3}:C OSLDs in therapeutic proton beams, dependence on beam quality was smallest for readout protocols that selected the blue emission band with small integration times. DA Granville received financial support from the Natural Sciences and Engineering

  14. Dose evaluation using multiple-aliquot quartz OSL: Test of methods and a new protocol for improved accuracy and precision

    DEFF Research Database (Denmark)

    Jain, M.; Bøtter-Jensen, L.; Singhvi, A.K.

    2003-01-01

    -dose-dependent sensitivity changes during the pre-heat, and fundamental variability in the shapes of quartz OSL (blue-green or blue-light stimulated luminescence) decay forms. A new protocol using a combination of 'elevated temperature IR cleaning' (ETIR) and 'component-specific dose normalisation' (CSDN) has been developed....... CSDN accounts for variability in the OSL decay forms and absorbs such sensitivity changes. A combination of ETIR and CSDN protocol increased palaeodose precision from +/-100% to +/-4% in quartz separates from the fluvially transported sands in the Thar desert. A comparison with palaeodose estimates...

  15. Study of combinations of TL/OSL single dosimeters for mixed high/low ionization density radiation fields

    International Nuclear Information System (INIS)

    Oster, L.; Druzhyna, S.; Orion, I.; Horowitz, Y.S.

    2013-01-01

    In this paper we discuss and compare the potential application of combined OSL/TL measurements using 6 LiF:Mg,Ti (TLD-600 is enriched of isotope 6 Li which has a high cross-section for the reaction with slow neutrons) or 7 LiF:Mg,Ti ( TLD-700 is enriched of 7 Li isotope) and TLD-100 (natural isotopic composition) detectors. The OSL/TL duel readout of LiF:Mg,Ti as an ionization density discriminator avoids some of the difficulties inherent to the various types of discrimination mixed-field passive dosimeters, and in addition has several advantages. The preferential excitation of OSL compared to TL following high ionization density (HID) alpha irradiation, naturally explained via the identification of OSL with the “two-hit” F 2 or F 3 center, whereas the major component of composite TL glow peak 5 is believed to arise from a ''one-hit'' complex defect. This evidence allows near-total discrimination between HID radiation and low-ionization density (LID) radiation. Beta and alpha particle irradiations were carried out with 90 Sr/ 90 Y (∼500 keV average energy) and 241 Am sources (4.7 MeV) respectively and neutron irradiations were carried out at the PTB (Germany) (E n = 5 MeV) and RARAF (Columbia University, USA) (E n = 6 MeV) accelerator facilities. The highest values of the FOM obtained was ∼30 for neutron/gamma discrimination and ∼110 for alpha/gamma discrimination using OSL/TL – peak 5 measurements in TLD-700. -- Highlights: ► The increased response of OSL compared to TL following HID irradiation is observed. ► This evidence is explained via the identification of OSL with the ''two-hit'' F2 centers. ► The potential application of combined OSL/TL in discrimination dosimetry is discussed. ► The values of FOM were 110 for alpha/gamma and 30 for neutron/gamma discrimination

  16. Single-grain quartz OSL dating of debris flow deposits from Men Tou Gou, south west Beijing, China

    DEFF Research Database (Denmark)

    Zhao, Qiuyue; Thomsen, Kristina Jørkov; Murray, A. S.

    2017-01-01

    of the return frequency of these debris flows, risk assessment and climate change research. In this project, we use quartz single-grain optically stimulated luminescence (OSL) methods to determine the burial ages of five debris flow samples from the Zhai Tang region -60 km west of Beijing. OSL characteristics...... poorly bleached prior to deposition; relative over-dispersions are larger than 60%. Minimum age modelling indicates that all five samples were deposited within the past few hundred years, indicating that catastrophic debris flows are occurring under the historically-recent land-use pattern....

  17. Investigation of OSL signal of resistors from mobile phones for accidental dosimetry

    International Nuclear Information System (INIS)

    Mrozik, A.; Marczewska, B.; Bilski, P.; Gieszczyk, W.

    2014-01-01

    Resistors from mobile phones, usually located near the human body, are considered as individual dosimeters of ionizing radiation in emergency situations. The resistors contain Al 2 O 3 , which is optically stimulated luminescence (OSL) material sensitive to ionizing radiation. This work is focused on determination of dose homogeneity within mobile phones which was carried out by OSL measurements of resistors placed in different parts inside the mobile phone. Separate, commercially available resistors, similar in the shape and size to the resistors from circuit board of the studied mobile phone, were situated in different locations inside it. The irradiations were performed in uniform 60 Co and 137 Cs radiation fields, with the mobile phones connected and not connected to the cellular network. The dose decrease of 9% was measured for original resistors situated between circuit board and battery, in comparison to the dose at the front of the phone. The resistors showed the lower signal when the mobile phone was connected to the cellular network, due to higher temperature inside the housing. The profile of fading was investigated within 3 month period for resistors irradiated with 1 Gy of gamma rays to estimate of the fading coefficient. - Highlights: • Impact of a mobile phone mode (switched on/off) on absorbed dose by resistors was showed. • The influence of the temperature during irradiation on absorbed dose was measured. • Dose distribution inside of a mobile phone was performed. • Fading factor of resistors was calculated

  18. Sources of uncertainty in individual monitoring for photographic,TL and OSL dosimetry techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Max S.; Silva, Everton R.; Mauricio, Claudia L.P., E-mail: max.das.ferreira@gmail.com, E-mail: everton@ird.gov.br, E-mail: claudia@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The identification of the uncertainty sources and their quantification is essential to the quality of any dosimetric results. If uncertainties are not stated for all dose measurements informed in the monthly dose report to the monitored radiation facilities, they need to be known. This study aims to analyze the influence of different sources of uncertainties associated with photographic, TL and OSL dosimetric techniques, considering the evaluation of occupational doses of whole-body exposure for photons. To identify the sources of uncertainty it was conducted a bibliographic review in specific documents that deal with operational aspects of each technique and the uncertainties associated to each of them. Withal, technical visits to individual monitoring services were conducted to assist in this identification. The sources of uncertainty were categorized and their contributions were expressed in a qualitative way. The process of calibration and traceability are the most important sources of uncertainties, regardless the technique used. For photographic dosimetry, the remaining important uncertainty sources are due to: energy and angular dependence; linearity of response; variations in the films processing. For TL and OSL, the key process for a good performance is respectively the reproducibility of the thermal and optical cycles. For the three techniques, all procedures of the measurement process must be standardized, controlled and reproducible. Further studies can be performed to quantify the contribution of the sources of uncertainty. (author)

  19. OSL and TL of Resistors of Mobile Phones for Retrospective Accident Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. I.; Kim, J. L.; Pradhan, A. S.; Chang, I.; Kim, B. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Optically stimulated luminescence (OSL) and thermoluminescence (TL) of ubiquitous materials continue to draw wider attention for individual dosimetry in nuclear and radiation accidents. Use of ubiquitous objects for radiation dosimetry is preferred because the affected persons in such unexpected events are usually not covered by personal dosimetry services and do not carry personal dosimeters. Often accident sites do not have area monitoring system in place. As the main concern of the dosimetry is health effects, a quick distinction of level of exposures of the affected persons for the required medical care becomes important in all accidents involving radiation. Both in large scale nuclear accidents such Fukushima, Chernobyl or Hiroshima and Nagasaki where large population around the accident site get exposed to radiation (evacuation is based on doses) and in smaller but panicky events, such as misuse of radiological exposure device (RED), radiological dispersive device (RDD: 'Dirty Bomb'), improvised nuclear device (IND) and deliberate dispersal of radioactive contaminants, a need for an ubiquitous personal dosimeter is well recognized. As biological dosimetry systems are yet to become viable for measurements of doses with required accuracy and speed, use of physical dosimeters is often explored. Among the various types of physical dosimetry systems, use of TL and OSL by processing common material such as bricks or tiles and measuring the doses cumulated for long periods of time has already become an accepted tool for large scale nuclear accidents such as Hiroshima and Nagasaki or Chernobyl involving higher doses. In the other potential cases of unexpected situations where the doses encountered could be much lower (even to escape the range of remotely installed area monitors), the need to measure even the low doses in shortest possible time becomes important. It is often realized that in such situations, the main problem could become the panic at the

  20. OSL and TL of Resistors of Mobile Phones for Retrospective Accident Dosimetry

    International Nuclear Information System (INIS)

    Lee, J. I.; Kim, J. L.; Pradhan, A. S.; Chang, I.; Kim, B. H.

    2012-01-01

    Optically stimulated luminescence (OSL) and thermoluminescence (TL) of ubiquitous materials continue to draw wider attention for individual dosimetry in nuclear and radiation accidents. Use of ubiquitous objects for radiation dosimetry is preferred because the affected persons in such unexpected events are usually not covered by personal dosimetry services and do not carry personal dosimeters. Often accident sites do not have area monitoring system in place. As the main concern of the dosimetry is health effects, a quick distinction of level of exposures of the affected persons for the required medical care becomes important in all accidents involving radiation. Both in large scale nuclear accidents such Fukushima, Chernobyl or Hiroshima and Nagasaki where large population around the accident site get exposed to radiation (evacuation is based on doses) and in smaller but panicky events, such as misuse of radiological exposure device (RED), radiological dispersive device (RDD: 'Dirty Bomb'), improvised nuclear device (IND) and deliberate dispersal of radioactive contaminants, a need for an ubiquitous personal dosimeter is well recognized. As biological dosimetry systems are yet to become viable for measurements of doses with required accuracy and speed, use of physical dosimeters is often explored. Among the various types of physical dosimetry systems, use of TL and OSL by processing common material such as bricks or tiles and measuring the doses cumulated for long periods of time has already become an accepted tool for large scale nuclear accidents such as Hiroshima and Nagasaki or Chernobyl involving higher doses. In the other potential cases of unexpected situations where the doses encountered could be much lower (even to escape the range of remotely installed area monitors), the need to measure even the low doses in shortest possible time becomes important. It is often realized that in such situations, the main problem could become the panic at the work place

  1. Optimization of CW-OSL parameters for improved dose detection threshold in Al2O3:C

    International Nuclear Information System (INIS)

    Rawat, N.S.; Dhabekar, B.; Kulkarni, M.S.; Muthe, K.P.; Mishra, D.R.; Soni, A.; Gupta, S.K.; Babu, D.A.R.

    2014-01-01

    Continuous wave optically stimulated luminescence (CW-OSL) is relatively a simple technique that offers good signal to noise ratio (SNR) and involves simple instrumentation. This study reports the influence and optimization of CW-OSL parameters on minimum detectable dose (MDD) using α-Al 2 O 3 :C phosphor. It is found that at a given stimulation intensity MDD in CW-OSL mode depends on signal integration time. At lower integration times MDD is inferior. It exhibits an improvement for intermediate values, shows a plateau region and deteriorates as integration time increases further. MDD is found to be ∼127 μGy at 4 mW/cm 2 stimulation intensity for integration time of 0.1 s, which improves to ∼10.5 μGy for 60 s. At stimulation intensity of 72 mW/cm 2 , MDD is 37 μGy for integration time of 60 s and improves significantly to 7 μGy for 1 s. - Highlights: • CW-OSL parameters are optimized to obtain best SNR and MDD in Al 2 O 3 :C. • MDD is found to depend on signal integration time and stimulation intensity. • With time, MDD initially improves, stabilizes then deteriorates. • At a given intensity, MDD is optimum for a certain range of integration time

  2. Study of sensitivity change of OSL signals from quartz and feldspars as a function of preheat temperature

    DEFF Research Database (Denmark)

    Jungner, H.; Bøtter-Jensen, L.

    1994-01-01

    and as a result, the equivalent dose (ED) would be underestimated. A study of sensitivity changes in feldspars and quartz was carried out with emphasis on the effect of preheat and annealing on the OSL signal. Measurement results obtained are presented, and possible elimination of errors in dating caused...

  3. An application of artificial neural intelligence for personal dose assessment using a multi-area OSL dosimetry system

    International Nuclear Information System (INIS)

    Lee, S.-Y.Sang-Yoon.; Kim, B.-H.Bong-Hwan; Lee, K.J.Kun Jai

    2001-01-01

    Significant advances have been made in recent years to improve measurement technology and performance of phosphor materials in the fields of optically stimulated luminescence (OSL) dosimetry. Pulsed and continuous wave OSL studies recently carried out on α-Al 2 O 3 : C have shown that the material seems to be the most promising for routine application of OSL for dosimetric purposes. The main objective of the study is to propose a new personal dosimetry system using α-Al 2 O 3 : C by taking advantage of its optical properties and energy dependencies. In the process of the study, a new dose assessment algorithm was developed using artificial neural networks in hopes of achieving a higher degree of accuracy and precision in personal OSL dosimetry system. The original hypothesis of this work is that the spectral information of an X- and γ-ray fields may be obtained by the analysis of the response of a multi-element system. In this study, a feedforward neural network using the error back-propagation method with Bayesian optimization was applied for the response unfolding procedure. The validation of the proposed algorithm was investigated by unfolding the 10 measured responses of α-Al 2 O 3 : C for arbitrarily mixed photon fields which range from 20 to 662 keV

  4. Quartz OSL dating of late quaternary Chinese and Serbian loess: A cross Eurasian comparison of dust mass accumulation rates

    DEFF Research Database (Denmark)

    Peric, Zoran; Adolphi, Emma Lagerbäck; Stevens, Thomas

    2018-01-01

    on multi-millennial timescales, with no detailed examination of dust MAR at the two ends of the Eurasian loess belt on shorter, sub-orbital scales. Here we present a detailed quartz optically stimulated luminescence (OSL) chronology from the Serbian Titel Loess Plateau (Veliki Surduk loess core...

  5. On the use of OSL of wire-bond chip card modules for retrospective and accident dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Woda, Clemens [Helmholtz Zentrum Muenchen - German Research Centre for Environmental Health, Institute of Radiation Protection, Ingolstaedter Landstrasse 1, D-85764 Neuherberg (Germany)], E-mail: clemens.woda@helmholtz-muenchen.de; Spoettl, Thomas [Infineon Technologies AG, Wernerwerkstrasse 1, D-93049 Regensburg (Germany)

    2009-05-15

    The potential of optically stimulated luminescence of wire-bond chip card modules, used in health insurance, ID, cash and credit cards for retrospective and accident dosimetry is investigated. Chip card modules obtained directly from the producer, using a widely spread UV-cured epoxy product for encapsulation, are used as basis for the study. The radiation sensitivity is due to silica grains added to the epoxy for controlling the thixotropic properties. Luminescence properties are complex due to the presumed thermo-optical release of electrons from the epoxy and transfer into the silica. Best results and highest sensitivity are obtained by using no or only low preheat treatments. A high degree of fading of the OSL signal during storage at room temperature is observed, which is tentatively explained by the superposition of thermal decay of shallow OSL traps and athermal (anomalous) decay of deeper OSL traps. The dose response of the OSL signal shows exponentially saturating behaviour, with saturation doses of 77 Gy or 9.6 Gy, depending on pretreatment. Dose recovery tests show that given doses can be recovered within a deviation of {+-}14%, if measured signals are corrected for fading. The minimum detectable dose is estimated at {approx}3 mGy, {approx}10 mGy and {approx}20 mGy for readouts immediately, 1 day and 10 days after exposure, respectively.

  6. Development of pulsed stimulation and Photon Timer attachments to the Risø TL/OSL reader

    DEFF Research Database (Denmark)

    Lapp, Torben; Jain, Mayank; Ankjærgaard, Christina

    2009-01-01

    in the OSL/IRSL process, a Photon Timer attachment to the Risø reader has been developed which measures data at 100 ps resolution. Furthermore a post-processing program has been developed to present the data in a compressed 3D form that gives a useful overview of the data before further analysis of relevant...

  7. Single-grain and multi-grain OSL dating of river terrace sediments in the Tabernas Basin, SE Spain

    DEFF Research Database (Denmark)

    Geach, M.R.; Thomsen, Kristina Jørkov; Buylaert, Jan-Pieter

    2015-01-01

    River terraces represent important records of landscape response to e.g. base-level change and tectonicmovement. Both these driving forces are important in the southern Iberian Peninsula. In this study,Optically Stimulated Luminescence (OSL) dating was used to date two principal river terraces...

  8. Optically stimulated luminescence (OSL) dating of shallow marine sediments to develop an analysis method of late Quaternary geodynamics

    International Nuclear Information System (INIS)

    Hataya, Ryuta; Shirai, Masaaki

    2003-01-01

    To develop an analysis method of geodynamics, we have examined the applicability of the OSL dating of marine terrace deposits. We have done the OSL dating, using the multiple-aliquot additive-dose technique, of shallow marine sediments from the upper part the Kioroshi Formation in Ibaraki Prefecture, which are correlated to Marine Oxygen Isotope Stage (MIS) 5e-5c. Marine terrace deposit consists mainly of shallow marine sediment. OSL ages of foreshore and foreshore-shoreface beds are 88-112 Ka, and are in good agreement with the geological/geomorphological data. On the other hand, OSL ages of the backshore bed are younger, and ones of the shoreface bed are older than geologically estimated ages. These results show that OPSL dating method can date shallow marine sediment using samples from foreshore and foreshore-shoreface beds, and that this method can distinguish terrace deposits formed in MIS5 and that in MIS7 by taking geomorphologic information into account. These results contribute to the characterization of long-term geological movement in coastal areas. (author)

  9. Optically stimulated luminescence (OSL) dating of quartzite cobbles from the Tapada do Montinho archaeological site (east-central Portugal)

    DEFF Research Database (Denmark)

    Sohbati, Reza; Murray, Andrew S.; Buylaert, Jan-Pieter

    2012-01-01

    The burial age of an alluvially deposited cobble pavement at the Tapada do Montinho archaeological site (east-central Portugal) is investigated using optically stimulated luminescence (OSL) dating. Measurements on the cobbles (quartzite clasts) were carried out on intact slices and large aliquots...

  10. Characterization of an optically stimulated luminescence (OSL) material for thermal neutron detection: SrS:Ce,Sm,B

    International Nuclear Information System (INIS)

    Ravotti, Federico; Garcia, Pierre; Prevost, Hildegarde; Dusseau, Laurent; Lapraz, Dominique; Vaille, Jean-Roch; Benoit, David

    2008-01-01

    SrS:Ce,Sm exhibits some interesting phosphorescent and charge storage properties that are used in OSL (optically stimulated luminescence) radiation dosimetry. To enhance the thermal neutron sensitivity of this phosphor, a new material obtained by boron doping has been developed. This OSL, B material was analysed with respect to its optical and structural characteristics in order to study possible modifications induced by doping procedure. Optical study highlights a decrease in the material luminescence of about 40% with TL and OSL experiments. The emission spectrum remains the same after boron addition. This result is in agreement with the structural characterization analysis since the lattice parameters were not modified. 11B MAS NMR results indicate that boron atoms are present in the host lattice in form of BO4 groups. Consequences on dosimetry applications are discussed. The neutron response of the OSL, B irradiated in a nuclear reactor is linear up to a fluence of 5 x 1011 cm -2 and it is possible to separate the thermal neutron and gamma components. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. Reliability of equivalent-dose determination and age-models in the OSL dating of historical and modern palaeoflood sediments

    DEFF Research Database (Denmark)

    Medialdea, Alicia; Thomsen, Kristina Jørkov; Murray, Andrew Sean

    2014-01-01

    model to small aliquot (similar to 30 grains) dose distributions. From our study we conclude that these and similar young slack-water flood deposits can be accurately dated using quartz OSL, opening up the possibility of establishing time series of flood discharge in catchments for which no instrumental...

  12. On the use of OSL of wire-bond chip card modules for retrospective and accident dosimetry

    International Nuclear Information System (INIS)

    Woda, Clemens; Spoettl, Thomas

    2009-01-01

    The potential of optically stimulated luminescence of wire-bond chip card modules, used in health insurance, ID, cash and credit cards for retrospective and accident dosimetry is investigated. Chip card modules obtained directly from the producer, using a widely spread UV-cured epoxy product for encapsulation, are used as basis for the study. The radiation sensitivity is due to silica grains added to the epoxy for controlling the thixotropic properties. Luminescence properties are complex due to the presumed thermo-optical release of electrons from the epoxy and transfer into the silica. Best results and highest sensitivity are obtained by using no or only low preheat treatments. A high degree of fading of the OSL signal during storage at room temperature is observed, which is tentatively explained by the superposition of thermal decay of shallow OSL traps and athermal (anomalous) decay of deeper OSL traps. The dose response of the OSL signal shows exponentially saturating behaviour, with saturation doses of 77 Gy or 9.6 Gy, depending on pretreatment. Dose recovery tests show that given doses can be recovered within a deviation of ±14%, if measured signals are corrected for fading. The minimum detectable dose is estimated at ∼3 mGy, ∼10 mGy and ∼20 mGy for readouts immediately, 1 day and 10 days after exposure, respectively.

  13. Study of morphological and luminescent properties (TL and OSL) of ZnO nanocrystals synthetized by coprecipitation method

    Energy Technology Data Exchange (ETDEWEB)

    Soares, A.F., E-mail: alvarodefarias@hotmail.com; Tatumi, S.H., E-mail: sonia.tatumi@gmail.com; Mazzo, T.M.; Rocca, R.R.; Courrol, L.C.

    2017-06-15

    In this work, ZnO nanocrystalline phosphorus were synthesized using the method of coprecipitation, subsequently different heat treatments at 900 and 1000 °C for 2 h and 1000 °C for 4 h were performed. Afterward, Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) emissions were verified after exposure to β-radiation. Photoluminescence results showed UV and VIS emissions. Morphological studies with X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) confirmed the crystallinity of the samples, with their well-shaped wurtzite hexagonal structures in nanoscale. ZnO calcinated at 900 °C – 2 h emitted a broad TL peak located between the 362–372 °C; for ZnO calcinated at 1000 °C – 2 h, two intense peaks were observed at 144 and 308 °C, this TL emission curve was investigated with more details using Computerized Glow Curve Deconvolution and six individual TL peaks were obtained, for sample irradiated with 40.6 Gy, corroborating with the T{sub m}-T{sub stop} results. A study of Minimum Detectable Dose (MDD) was made and a dose of (492±40) μGy was determined. CW-OSL and LM-OSL analysis were made for ZnO calcinated at 1000 °C – 2 h, allowed to verify the behaviour, and the curve existing components (fast and medium, depending on dose). As well as the calculation of the Minimum Detectable Dose for CW-OSL. - Highlights: •ZnO nanocrystals were successfully produced by the method of coprecipitation. •Grains sizes by Scherrer Equation were between 26.9–40.6 nm, corroborating with SEM. •Study of the TL emission: Computerized Glow Curve Deconvolution (CGCD) and Tm-Tstop. •TL emission of ZnO calcinated supplied the minimum detectable dose of (492±40) μGy. •Study of CW-OSL and LM-OSL with CGCD. MDD for CW-OSL evaluation of ZnO calcinated.

  14. Introduction of a new dosimetry system based on optically stimulated luminescence (OSL) in our personal monitoring service

    International Nuclear Information System (INIS)

    Hubner, S.

    2014-08-01

    The personal monitoring service named Auswertungsstelle is part of the Helmholtz Zentrum Munchen, a non-profit-making research center in Germany. As one of the four monitoring services in Germany, we have been a reliable partner in radiation protection for more than 60 years. With about 1.9 million dose assessments per year, we are the largest monitoring service in Europe. For dozens of years, our main dosimeter used in whole-body dosimetry has been a film dosimeter. Although its dosimetric properties are still up to date, film dosimetry won.t be a sustainable technique for the use in monitoring services. Therefore, a project with the objective of investigating alternative dosimetric materials and methods was launched in the late 1990 at the Helmholtz Zentrum Munchen. Based on this research work, the use of Be O as an OSL dosimeter was studied by the radiation physics group of the Tu Dresden, by order and on account of the Auswertungsstelle at the Helmholtz Zentrum Munchen. It was shown, that ceramic Be O features promising dosimetric properties, making Be O detectors particularly suitable for being used in all applications in whole-body dosimetry measuring photons. Ceramic Be O material has an excellent resistance to environmental influences. The Be O chips are almost tissue equivalent. Therefore, these detectors show low photon energy dependence. A new personal dosimetry system based on the OSL dosimetry of Be O was developed. Applying this system, the Auswertungsstelle offers OSL-dosimeters for official monitoring of the Personal Dose Equivalent Hp(10) since 2011. This OSL-System is accredited according to DIN IEC 62387 and we obtained the corresponding type approval by the Ptb, the national metrology institute in Germany. Sophisticated logistics was developed and installed. High degree of automation was achieved by robots for dosimeter assembly and machines for packing, labelling and unpacking of the dosimeters. To become a sustainable dosimetry system not only

  15. Introduction of a new dosimetry system based on optically stimulated luminescence (OSL) in our personal monitoring service

    Energy Technology Data Exchange (ETDEWEB)

    Hubner, S., E-mail: stephan.huebner@helmholtz-muenchen.de [Helmholtz Zentrum Munchen, German Research Center for Environmental Health, D-80219, Munich (Georgia)

    2014-08-15

    The personal monitoring service named Auswertungsstelle is part of the Helmholtz Zentrum Munchen, a non-profit-making research center in Germany. As one of the four monitoring services in Germany, we have been a reliable partner in radiation protection for more than 60 years. With about 1.9 million dose assessments per year, we are the largest monitoring service in Europe. For dozens of years, our main dosimeter used in whole-body dosimetry has been a film dosimeter. Although its dosimetric properties are still up to date, film dosimetry won.t be a sustainable technique for the use in monitoring services. Therefore, a project with the objective of investigating alternative dosimetric materials and methods was launched in the late 1990 at the Helmholtz Zentrum Munchen. Based on this research work, the use of Be O as an OSL dosimeter was studied by the radiation physics group of the Tu Dresden, by order and on account of the Auswertungsstelle at the Helmholtz Zentrum Munchen. It was shown, that ceramic Be O features promising dosimetric properties, making Be O detectors particularly suitable for being used in all applications in whole-body dosimetry measuring photons. Ceramic Be O material has an excellent resistance to environmental influences. The Be O chips are almost tissue equivalent. Therefore, these detectors show low photon energy dependence. A new personal dosimetry system based on the OSL dosimetry of Be O was developed. Applying this system, the Auswertungsstelle offers OSL-dosimeters for official monitoring of the Personal Dose Equivalent Hp(10) since 2011. This OSL-System is accredited according to DIN IEC 62387 and we obtained the corresponding type approval by the Ptb, the national metrology institute in Germany. Sophisticated logistics was developed and installed. High degree of automation was achieved by robots for dosimeter assembly and machines for packing, labelling and unpacking of the dosimeters. To become a sustainable dosimetry system not only

  16. Remodelagem do sistema computacional para dosimetria em radioterapia por nêutrons e fótons baseado em métodos estocásticos - SISCODES

    OpenAIRE

    Bruno Machado Trindade

    2011-01-01

    O presente trabalho apresenta a remodelagem do Sistema Computacional para Dosimetria em Radioterapia por Nêutrons e Fótons Baseado em Métodos Estocásticos . SISCODES. Para isso mostra a proposta inicial e estado anterior do sistema, as modificações e expansões propostas e executadas, e o estado atual de desenvolvimento do sistema. Melhorias futuras são propostas ao final do trabalho. O SISCODES é um sistema que permite a execução de planejamento computacional 3D em radioterapia, através de si...

  17. Management of radioactive wastes from HNMD (Hospital Naval Marcilio Dias) and from IRD (Instituto de Radioprotecao e Dosimetria) due to the accident in Goiania

    International Nuclear Information System (INIS)

    Peres, S.S.; Silva, J.J.G.

    1988-01-01

    A description of the methods and procedures for the management of the radwastes from HNMD (Hospital Naval Marcilio Dias) and from IRD (Instituto de Radioprotecao e Dosimetria) due to the radioactive accident at Goiania City, is presented. Basically the radwastes are consituted by excreta of persons involved in the accident and materials used for medicals care of patients. The method employed for treatment of faeces was its aggregation in lime and cement and for the case of urine, ion exchange resing, was used. Others type of radwastes were compacted or simply conditionned. Many releases to the environment, were possible. (author) [pt

  18. Dosimetria e monitoração de feixes estreitos de raios-X, produzidos por acelerador linear de particulas, para aplicação em radiocirurgia

    OpenAIRE

    Jose Carlos Ferraz de Campos

    1986-01-01

    Resumo: O presente trabalho teve como objetivo principal investigar as características principais de dosimetria e monitoração de feixes finos de raios-x, e sua aplicação a um Acelerador Linear de Partículas de 4 MV, para seu emprego na Radiocirurgia. Com esta finalidade, construiu-se um sistema de colimação adicional, composto de 3 colimadores de Chumbo, que permite, a partir do campo mínimo protocolar produzido pelo acelerador, obter os feixes finos de 6, 10 e 15 mm de diâmetros. Um siste...

  19. OSL and TL dosimeter characterization of boron doped CVD diamond films

    Science.gov (United States)

    Gonçalves, J. A. N.; Sandonato, G. M.; Meléndrez, R.; Chernov, V.; Pedroza-Montero, M.; De la Rosa, E.; Rodríguez, R. A.; Salas, P.; Barboza-Flores, M.

    2005-04-01

    Natural diamond is an exceptional prospect for clinical radiation dosimetry due to its tissue-equivalence properties and being chemically inert. The use of diamond in radiation dosimetry has been halted by the high market price; although recently the capability of growing high quality CVD diamond has renewed the interest in using diamond films as radiation dosimeters. In the present work we have characterized the dosimetric properties of diamond films synthesized by the HFCVD method. The thermoluminescence and the optically stimulated luminescence of beta exposed diamond sample containing a B/C 4000 ppm doping presents excellent properties suitable for dosimetric applications with β-ray doses up to 3.0 kGy. The observed OSL and TL performance is reasonable appropriate to justify further investigation of diamond films as dosimeters for ionizing radiation, specially in the radiotherapy field where very well localized and in vivo and real time radiation dose applications are essential.

  20. OSL dating of fine-grained quartz from Holocene Yangtze delta sediments

    DEFF Research Database (Denmark)

    Sugisaki, Saiko; Buylaert, Jan-Pieter; Murray, Andrew

    2015-01-01

    Holocene flood events in the Yangtze River are associated with variations in East Asian Summer Monsoon (EASM) precipitation, and so Yangtze delta sediments may preserve information about the frequency and magnitude of EASM precipitation. These flood/drought cycles of the EASM directly affect...... the living standards of East Asian population. However, despite its importance, little chronological control is available for the Yangtze Delta sediments; because biogenic carbonate only occurs sporadically, it has proved the difficulty to discuss sedimentation mechanisms and rates in any detail. In 2013 two...... sediment cores (YD13-G3 and H1) were taken from the Yangtze subaqueous delta to investigate precipitation history. In this study, we investigate the potential of quartz OSL dating of the fine silt fraction (fine-grained quartz; 4-11 μm) from these cores to estimate the depositional age of the sediments. We...

  1. The dose dependency of the over-dispersion of quartz OSL single grain dose distributions

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, Andrew S.; Jain, Mayank

    2012-01-01

    The use of single grain quartz OSL dating has become widespread over the past decade, particularly with application to samples likely to have been incompletely bleached before burial. By reducing the aliquot size to a single grain the probability of identifying the grain population most likely...... to have been well-bleached at deposition is maximised and thus the accuracy with which the equivalent dose can be determined is – at least in principle – improved. However, analysis of single grain dose distributions requires knowledge of the dispersion of the well-bleached part of the dose distribution....... This can be estimated by measurement of a suitable analogue, e.g. a well-bleached aeolian sample, but this requires such an analogue to be available, and in addition the assumptions that the sample is in fact a) well-bleached, and b) has a similar dose rate heterogeneity to the fossil deposit. Finally...

  2. A compact design for monochromatic OSL measurements in the wavelength range 380-1020 NM

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Poolton, N.R.J.; Willumsen, F.

    1994-01-01

    automated Riso TL/OSL dating apparatus, thus allowing for either routine scanning or more detailed thermo-optical investigations. The high throughput efficiency of the unit means that the existing 75 W tungsten-halogen lamp can be directly used for such measurements on both quartz and feldspar samples......The development and performance of a compact module is described that allows for the monochromatic illumination of samples in the wavelength range 380-1020 nm, enabling the measurement of energy-resolved optically stimulated luminescence. The unit is designed to couple directly to the existing....... The design allows for rapid spectral scanning with a choice of resolution of anywhere between 10 and 80 nm: stray light levels are less than 0.01%. The unit can equally be used for recording wavelength-resolved emission spectra, whether photo-excited or thermally stimulated; the capabilities of the system...

  3. On the use of OSL of chip card modules with molding for retrospective and accident dosimetry

    International Nuclear Information System (INIS)

    Woda, Clemens; Fiedler, Irene; Spöttl, Thomas

    2012-01-01

    The potential of optically stimulated luminescence of wire-bond chip card modules with molded encapsulations for retrospective and accident dosimetry is investigated. Contact-based and contactless modules were studied, the latter finding potential use in electronic documents (e.g. electronic passports, electronic identity cards). Investigations were carried out on intact as well as chemically prepared modules, extracting the filler material. Contact-based modules are characterized according to zero dose signal, correlation between OSL and TL, dose response and long-term signal stability. For prepared modules, the minimum detectable dose immediately after irradiation is 3 mGy and between 20 and 200 mGy for contact-based and contactless modules, respectively. Dose recovery tests on contact-based modules indicate that the developed methodology yields results with sufficient accuracy for measurements promptly after irradiation, whereas a systematic underestimation is observed for longer delay times. The reasons for this behaviour are as yet not fully understood.

  4. New data on OSL dating of Early Khalynian deposits of Northern Caspian

    Science.gov (United States)

    Sychev, Nikita; Yanina, Tamara; Svitoch, Alexander; Kurbanov, Redzhep; Badyukova, Ekaterina

    2016-04-01

    Ponto-Caspian region is the key region the study of which can provide information about the paleogeographic history of the central Eurasia, particularly revealing the history of the East European Plain, the Caucasus and Central Asia. However, despite the long history of the study, today there is no accepted general stratigraphic scheme of the Caspian Sea. One of the most interesting and important stages of Late Pleistocene history of Caspian is Khalynian transgression which is divided into two major phases: early and ate. In the Caspian lowland Lower Khalynian stage are represented by a unique type of deposit - "chocolate clays". A distinctive feature of these sediments is widely distributed among Lower Khalynian deposits of Northern Caspian and the Volga region. All clay deposits are confined to the diverse origins of depression before-Khalynian relief. Chocolate clays formation consists of facies: mono-clay (typological), layered, sand- and silty-clay (Svitoch, Yanina, 1997). Determining the age of chocolate clays by optically stimulated luminescence (OSL) in our view will allow bettering the understanding of their genesis. Age of chocolate clays of Lower Volga was widely dated using the radiocarbon. However, the existing chronology is controversial, raises a number of issues, primarily due to the material of which are used for dating - thin shells of Caspian mollusks of the Didacna Eichw. genus, which are characterized by a significant isotopic exchange with the enclosing sediments (Arslanov, 2015). Lower Volga region is characterized by very complex geological structure of the Late Pleistocene deposits (alternating continental aeolian, alluvial and slope sediments with marine Caspian deposits of different age). There are many conflicting opinions, not only with respect to paleogeographic features of the area, but also to its precise chronology. The differences in opinion over the age of the individual stages of development of the Caspian Sea (transgressions and

  5. De determination for young samples using the standardised OSL response of coarse-grain quartz

    International Nuclear Information System (INIS)

    Burbidge, C.I.; Duller, G.A.T.; Roberts, H.M.

    2006-01-01

    It has recently been shown that it is possible to construct standardised curves of the sensitivity corrected growth in optically stimulated luminescence (OSL) with exposure to ionising radiation, and that they may be used in the dating of quartz and polymineral samples. Standardised growth curves are particularly advantageous where measurement time is limited, as once they have been defined, only the natural signal and the response to a subsequent test dose are required in order to determine the equivalent dose of a sub-sample. The present study is concerned with the application of the standardised growth curve approach to OSL dating of Holocene age samples. Systematic changes in the shape of the standardised growth curve of coarse-grain quartz are identified as the size of the test dose is varied, because of non-proportionality between the test dose and the luminescence test response. The effect is characterised by fitting the change in gradient of the standardised growth curve as test dose is varied. An equation is defined to describe standardised growth as a function of regenerative dose and test dose. Regenerative dose responses of other samples in this study are treated as unknowns and recovered through different growth curves to compare precision and accuracy of various methods of D e determination. The standardised growth curve is found to yield similar precision to conventional fits of single aliquot regenerative data, but slightly poorer accuracy. The standardised growth curve approach was refined by incorporating the measurement of one regenerative response for each aliquot as well as its natural signal. Measurements of this additional data point for aliquots of 22 samples were used to adjust the standardised growth equation, improving its accuracy. The incorporation of this additional data point also indicated a systematic uncertainty of 2.4% in the estimates of D e

  6. Resetting of Quartz OSL (optically stimulated luminescence) Signals by Frictional Heating in Experimentally Sheared Gouges at Seismic Slip Rates.

    Science.gov (United States)

    Kim, J. H.; Choi, J. H.; Chauhan, N.; Lee, S.; Hirose, T.; Ree, J. H.

    2014-12-01

    Recent studies on natural and experimental seismic faults have revealed that frictional heating plays an important role in earthquake dynamics as well as in producing mineralogical and microstructural signatures of seismic faulting. Here, we report changes in OSL signals in quartz by frictional heating in experimental fault gouges. The gouges (80% of quartz and 20% of bentonite by weight) with a thickness of 1 mm were sheared between sandstone cylinders (diameter: 25 mm) at a normal stress of 1 MPa and slip rate of 1.31 m/s. The quartz grains from a sand dune on the western coast of South Korea were sieved to select size fractions between 90 and 250 μm. The equivalent dose (De) of the undeformed quartz grains was 8.0 ± 0.3 Gy. Upon displacement, the friction abruptly increases to the 1st peak (with friction coefficient μ ≈ 0.75) followed by slip weakening. Then the fault zones show two more peak frictions (μ ≈ 0.53~0.75) and finally reach a steady-state friction (μ ≈ 0.2~0.35). The fault can be divided into three zones based grain size (thus slip rate); slip localization (SLZ), intermediate slip-rate (ISZ) and low slip-rate (LSZ) zones. SLZ develops adjacent to the moving side of the sandstone cylinder with P-foliation and shear band. The size of quartz (Dq) in ISZ and LSZ is 5-30 μm and 50-250 μm, respectively. SEM and TEM analyses indicate that the fault gouge of SLZ consists of subangular quartz clasts (Dq ≈ 3 μm) and matrix of nano-scale quartz, unidentified silicate minerals and amorphous material. The fault zones were sectioned into six layers (~160 µm thick for each layer) parallel to the fault zone boundary for OSL analyses. Quartz grains from all the layers except the one immediately adjacent to the stationary side of the sandstone cylinder show De of 'effectively' 0 Gy indicating a full resetting of OSL signals. The partial resetting of OSL signal in the layer adjacent to the stationary side of the cylinder indicates the temperature (T

  7. Dependence of the anomalous fading of the TL and blue-OSL of fluorapatite on the occupancy of the tunnelling recombination sites

    International Nuclear Information System (INIS)

    Tsirliganis, N.C.; Polymeris, G.S.; Kitis, G.; Pagonis, V.

    2007-01-01

    The anomalous fading (AF) of thermoluminescence (TL) and optically stimulated luminescence (OSL) signals in Durango apatite is attributed to tunnelling effects. Electrons from the TL and OSL traps in this material are transferred, via a tunnelling effect, to the recombination sites. The availability of recombination sites for tunnelled electrons is of major importance for the degree of AF rate observed in this material. It is expected that a variation of the number of the electron recombination sites will be reflected in the experimentally measured AF rate. In the present work an investigation of the recombination sites for the tunnelled electrons is attempted by studying the AF effect using a special technique, in which the anomalously faded TL (OSL) is replaced by an equal amount of TL (OSL) induced by a beta dose

  8. Dosimetry of the patient and occupational in interventional procedures; Dosimetria del paciente y ocupacional en procedimientos intervencionistas

    Energy Technology Data Exchange (ETDEWEB)

    Andisco, D. [Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, C1121AAA Buenos Aires (Argentina); Bourel, V.; Schmidt, L.; Fernandez, N., E-mail: dandisco@fmed.uba.ar [Universidad Favaloro, Facultad de Ciencias e Ingenieria, Solis 453, C1078AAI, Buenos Aires (Argentina)

    2014-08-15

    The big necessity to estimate the entrance doses in skin that the patients receive when are exposed to interventional procedures and the personal dosimetry of the professionals that work in these procedures in operating room, has taken to the analysis of different possibilities that allow to carry out these estimates. The objective of this work was to analyze the possibility of using Optically Stimulated Luminescence dosimeters; comparing the results with ionizing cameras and electronic personal dosimeters. To carry out these estimates, we work with a X-ray equipment Phillips Allure, acrylic phantoms, a dosimetry system formed by ionization camera and dosimeter UNIDOS E, OSL (Nano dots) dosimeters and electronic lavalieres Aloka brand, PDM 117 models. To estimate the doses that the patients receive, entrance dose was measured in skin and in personal dosimetry inside places where the medical professionals are habitually located in different situations among 5 and 60 irradiation min. In the case of direct radiation, the OSL (Nano dots) present reliable readings and only were dispersed values for the measurements of secondary radiation. The measured values and the linking among them were also analyzed. The OSL (Nano dot) dosimetry behaves reliable way when is located in the ranges of more dose to 0,1 mGy, according to the maker indications and fundamentally for direct beams of the hemodynamics equipment being ideal for the measurement of entrance dose in skin. For the Nano dots use in personal dosimetry the results should be read carefully for values major to 0,1 mGy and being completely inappropriate for minor values. (Author)

  9. Potential and limits of OSL, TT-OSL, IRSL and pIRIR290 dating methods applied on a Middle Pleistocene sediment record of Lake El'gygytgyn, Russia

    Directory of Open Access Journals (Sweden)

    A. Zander

    2013-03-01

    Full Text Available This study tests the paleomagnetic and proxy-data based Mid- to Upper Pleistocene sediment deposition history of Lake El'gygytgyn by applying different approaches of luminescence dating techniques on sediment cores taken from the centre of the 175 m deep lake. For dating polymineral and quartz fine grains (4–11 μm grain size range were extracted from nine different levels from the upper 28 m of sediment cores 5011-1A and 5011-1B. According to the independent age model, the lowest sample from 27.8–27.9 m below lake bottom level correlates to the Brunhes-Matuyama (B/M reversal. Polymineral sub-samples were analysed by infra-red stimulated luminescence (IRSL and post-IR IRSL measured at 290 °C (pIRIR290 using single aliquot regenerative dose (SAR sequences. SAR protocols were further applied to measure the blue light optically stimulated luminescence (OSL and thermally-transferred OSL (TT-OSL of fine-grained quartz supplemented by a multiple aliquot approach. Neither low temperature IRSL measurements at 50 °C nor any OSL dating approach on quartz yielded reliable results. Deconvolution of their dose response curves revealed a pseudo-increase of the dose response curves and explains the observed underestimation. The pIRIR protocol applied to polymineral fine grains was the only luminescence technique able to provide dating results of acceptable accuracy up to ca. 700 ka when correlated to the existing proxy-data and paleomagnetic based age record. We present the potential and limits of the different dating techniques and a correlation of pIRIR290 results with the proxy-data based age model.

  10. Attaining provenance proxies from OSL and TL sensitivities: Coupling with grain size and heavy minerals data from southern Brazilian coastal sediments

    International Nuclear Information System (INIS)

    Zular, André; Sawakuchi, André O.; Guedes, Carlos C.F.; Giannini, Paulo C.F.

    2015-01-01

    In the São Francisco do Sul (SFS) barrier in southern Brazil, the optically stimulated luminescence (OSL) and thermoluminescence (TL) sensitivities of coastal sands vary according to geomorphological units. Sands from older beach ridges (ages older than 2000 years ago) show higher OSL and TL sensitivities than younger units (ages younger than 2000 years). Geomorphological units in the SFS attest to changes in provenance as a result of a coastal climate shift evidenced through grain size and heavy mineral analysis. We argue that in the SFS barrier sands, OSL and TL sensitivity signals provide an additional proxy to climate events and can be used as an alternative method to assess changes in provenance and tracking source-to-sink systems to monitor past and future environmental changes. - Highlights: • OSL and TL sensitivities are confronted with grain size and heavy minerals data. • We report OSL and 110 °C TL sensitivities as provenance proxies. • 110 °C TL sensitivity outlines environmental changes better than OSL sensitivity data.

  11. The TL and room temperature OSL properties of the glow peak at 110 deg. C in natural milky quartz: A case study

    International Nuclear Information System (INIS)

    Polymeris, George S.; Afouxenidis, Dimitrios; Tsirliganis, Nestor C.; Kitis, George

    2009-01-01

    The LM-OSL signal of quartz, while measured at room temperature, is dominated by an intermediate, broad and intense OSL component, so that its contribution and general characteristics are derived very accurately. Through a series of dose-response, bleaching and thermal decay at room temperature experiments, in conjunction with curve fitting studies, a component resolved analysis is carried out studying the correlation between this specific component, termed as LM-OSL component C 2 and the 110 deg. C TL glow peak in quartz. The dose-response of these two luminescence components behaves exactly similar being linear at low doses and saturating at almost 100 Gy. Both signals decay exponentially under illumination, providing identical optical detrapping cross-section values. Residual of both luminescence signals after thermal decay at room temperature follows an exponential law, yielding similar mean half-lives. All previous luminescence features provide strong evidence for the electron trap being the same for both the 110 deg. C TL trap and the LM-OSL component C 2 . The results of the present work are very promising and clearly support the possibility of extrapolating the TL pre-dose methodology to the OSL pre-dose effect using only the LM-OSL component C 2

  12. TL, OSL and C-14 dating results of the sediments and bricks from mummified nuns' grave

    Energy Technology Data Exchange (ETDEWEB)

    Tudela, Diego R.G.; Tatumi, Sonia H.; Yee, Marcio; Brito, Silvio L.M., E-mail: tatumi@fatecsp.br [Faculdades de Tecnologia de Sao Paulo (FATECs/CEETEPS/UNESP), Sao Paulo, SP (Brazil). Centro Estadual de Educacao Tecnologica Paula Souza; Morais, Jose L.; Morais, Daisy de; Piedade, Silvia C. [Universidade de Sao Paulo (USP), SP (Brazil). Museu de Arqueologia e Etnologia; Munita, Casimiro S.P.; Hazenfratz, Roberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-06-15

    This paper presents the results of TL and OSL dating of soil and fragments of bricks from a grave, which was occupied by two mummified nuns, found at 'Luz' Monastery, located in the state of Sao Paulo, Brazil. The TL and OSL ages were compared to C-14 dating ones obtained from bone collagens of the mummies. The majority of the ages is related to the eighteenth century. The gamma-ray spectroscopy was used to evaluate natural radioisotope concentrations in the samples, and by using these concentrations the annual dose rates, from 3.0 to 5.3 Gy/kyr, were obtained. Neutron activation analysis was performed and the radioisotope contents results are in agreement with those obtained by gamma-ray spectroscopy. The contents of U, Th and Ce elements were higher than those found in usual sediments. (author)

  13. Real time dose rate measurements with fiber optic probes based on the RL and OSL of beryllium oxide

    International Nuclear Information System (INIS)

    Teichmann, T.; Sponner, J.; Jakobi, Ch.; Henniger, J.

    2016-01-01

    This work covers the examination of fiber optical probes based on the radioluminescence and real time optically stimulated luminescence of beryllium oxide. Experiments are carried out to determine the fundamental dosimetric and temporal properties of the system and evaluate its suitability for dose rate measurements in brachytherapy and other applications using non-pulsed radiation fields. For this purpose the responses of the radioluminescence and optically stimulated luminescence signal have been investigated in the dose rate range of 20 mGy/h to 3.6 Gy/h and for doses of 1 mGy up to 6 Gy. Furthermore, a new, efficient analysis procedure, the double phase reference summing, is introduced, leading to a real time optically stimulated luminescence signal. This method allows a complete compensation of the stem effect during the measurement. In contrast to previous works, the stimulation of the 1 mm cylindrical beryllium oxide detectors is performed with a symmetric function during irradiation. The investigated dose rates range from 0.3 to 3.6 Gy/h. The real time optically stimulated luminescence signal of beryllium oxide shows a dependency on both the dose rate and the applied dose. To overcome the problem of dose dependency, further experiments using higher stimulation intensities have to follow. - Highlights: • RL and OSL measurements with BeO extended to low dose (rate) range. • A new method to obtain the real time OSL: Dual Phase Reference Summing. • Real time OSL signal shows both dose and dose rate dependency. • Real time OSL enables a complete discrimination of the stem effect.

  14. Mortar and surface dating with Optically Stimulated Luminescence (OSL): Innovative techniques for the age determination of buildings

    International Nuclear Information System (INIS)

    Panzeri, L.

    2013-01-01

    In this work the results of a dating study on bricks and mortars using both Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) are shown. The samples came from the outside walls of the Certosa di Pavia, located in northern Italy and independently dated (XVII-XVIII century). TL dating, applied to bricks using the fine grain technique, allowed to determine the time of manufacture of the bricks (XII century), that resulted therefore re-used. To circumvent this problem the application of two innovative dating techniques, OSL surface dating and mortar dating, was attempted. The first was applied to the light-shielded surfaces of bricks and allowed to successfully determine the edification of the wall (XVII century). Mortar dating gave instead severe age overestimation: the results obtained on coarse grain quartz with the SAR technique both on multi-grains aliquots and with single-grain analyses were highly dispersed indicating an incomplete bleaching of the quartz grains. The shine-down curves were in fact characterized by the absence of the so-called fast component, as confirmed by Linear Modulated OSL technique.

  15. Intercomparison of dispersed radiation readings among film dosimetry, electronic and OSL with X-rays for low dose

    International Nuclear Information System (INIS)

    Andisco, D.; Blanco, S.; Bourel, V.; Schmidt, L.; Di Risio, C.

    2014-08-01

    One of the personal dosimetry methods more used for several decades is the dosimetry type film, characterized to possess readings with certain margin of trust. Today other methods exist that many times are presupposed more reliable due to the nature of the detection like the electronic dosimeters or the OSL (Optically Stimulated Luminescence) dosimetry. With the purpose of comparing different methods and to can determining the existent differences among each method has been carried out an intercomparison assay. The different dosimeters have been exposed to dispersed radiation generated by a Hemodynamics equipment of the type -arch in C- and a dispersing system of the primary beam. Film dosimeters have been used; OSL (In Light), OSL (Nano Dots) and Electronic with the purpose of knowing and to valorize the existent differences among its readings. Always, the intercomparison exercises have demonstrated to be an useful tool when establishing the measurement capacity and the quality of the results emitted by the laboratories of personal dosimetry services. Also, this type of assays allows obtaining quality indicators of the laboratory performance and they are habitual part of the procedures for accreditation of the same ones. The Optically Stimulated Luminescence is a technology that has grown in Argentina so much in the area of personal dosimetry as in dosimetry in vivo (radiotherapy area). In this intercomparison study, the answers corresponding to each technology were looked for oneself irradiation of the disperse type, that is to say, of very low energy. (Author)

  16. Study of TSL and OSL properties of dental ceramics for accidental dosimetry applications

    International Nuclear Information System (INIS)

    Veronese, Ivan; Galli, Anna; Cantone, Marie Claire; Martini, Marco; Vernizzi, Fabrizio; Guzzi, Gianpaolo

    2010-01-01

    Interest is increasing in the development of new methodologies for accidental dose assessment, exploiting the luminescence and dosimetric properties of objects and materials which can be usually found directly on exposed subjects and/or in the contaminated area. In this work, several types of ceramics employed for dental prosthetics restoration, including both innovative materials used as sub-frames for the construction of the inner part of dental crowns (core), and conventional porcelains used for the fabrication of the external layer (veneer), were investigated with regard to their thermally and optically stimulated luminescence (TSL and OSL respectively) properties, in view of their potential application in accidental dosimetry. The sensitivity to ionizing radiation proved to strongly depend on the type and brand of ceramic, with minimum detectable dose ranging from few mGy up to several tens of mGy. A linear dose-response was observed for most of the samples. However, the luminescence signals were characterised by a significant fading, which has to be taken into account for a reliable accidental dose assessment after a radiation exposure event.

  17. Fake age hiatus in a loess section revealed by OSL dating of calcrete nodules

    Science.gov (United States)

    Zhang, Junjie; Li, Sheng-Hua; Sun, Jimin; Hao, Qingzhen

    2018-04-01

    Optically stimulated luminescence (OSL) dating on potassium feldspar has been performed with high resolution in the Luochuan section in the Chinese Loess Plateau. An age hiatus of ∼ 15 ka is found at the top of L2 layer within the loess/paleosol sequences. The age of the potassium feldspar from the calcrete nodules along the S1/L2 boundary is significantly older than those of the paleosol and loess samples lying above and below the boundary. The age overestimation of the potassium feldspar from calcrete nodules is caused by the underestimation of the dose rate, because accretion of carbonates could dilute the radioactivity. The age hiatus at the top of L2 also resulted from the underestimation of the dose rates of four loess samples beneath this hiatus. These four loess samples have high CaO concentrations. Ages of these samples are overestimated in the similar way as the nodules, but with smaller degrees. All results suggest that the accretion of carbonates happened after the loess deposition. The carbonate accretion process of the calcrete nodules has been simulated with accumulation models. The accretion can be as young as 46 ka, assuming the calcrete nodules formed rapidly at a certain time point. For slow and gradual accretion models, the carbonate started to accumulate slowly since the dust deposition and the accumulation became faster afterwards. The transition of the accretion rate may relate to the climate change or a change in the carbonate leaching and re-precipitation system.

  18. Error variation in OSL palaeodose estimates from single aliquots of quartz: a factorial experiment

    International Nuclear Information System (INIS)

    Galbraith, R.F.; Roberts, R.G.; Yoshida, H.

    2005-01-01

    We use a factorial experiment to study systematic and random differences between measured OSL palaeodoses for a variety of quartz samples. These include samples that have absorbed either a large or small natural or laboratory-induced radiation dose, either with or without prior heating or bleaching. The systematic factors studied are the size of the test dose, the preheat temperature and the number of quartz grains in each multi-grain aliquot. Palaeodoses were estimated using a single-aliquot regenerative-dose protocol. The main parameter of interest is the amount of random variation, over and above that due to photon counting statistics, to be expected between estimates from aliquots that have received the same radiation dose. This over-dispersion is generally larger for natural samples than for artificially bleached ones, and it varies from about 1% in the most favourable cases to about 18% for small aliquots of a sample that had received a natural dose of about 46 Gy. The latter is comparable to the over-dispersion reported for single grains of natural quartz that are thought to have been well-bleached at the time of deposition. The factorial experiment also revealed a number of systematic effects. In particular, measured palaeodoses using a preheat temperature of 260 deg. C were systematically lower than those using 180 deg. C, by up to about 5% in some cases

  19. Radiocromic film, TLD, OSL and 'Paracas Phantom' by dosimetric intercomparation in stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Paucar Jauregui, R.; Condori Marcos, P.; Vidarte Garcia, F.

    2008-01-01

    Full text: In Peru, one deals to patients with arteriovenous malformations or cerebral tumors by means of stereotactic radiosurgery, using fine photon beams of high energy of 6 MeV, generated by a linear accelerator Varian 2100 Clinac CD of the Complejo Hospitalario San Pablo in Lima, Peru. In this work we describes the 'Dosimetric Intercomparation System of the Quality Assurance Program in Stereotactic Radiosurgery of the Complejo Hospitalario San Pablo (DIS)'. The DIS allows to guarantee application of the doses with high accuracy. It shows the good performance of the Local DIS's components: dosimetry of radiocromics films, dosimetry termoluminiscent (TLD), dosimetry of optically stimulated luminescence (OSL) and an anthropomorphic phantom of head constructed locally, denominated 'Paracas Phantom'. Also, in the International DIS practiced with The University of Texas Md Anderson Cancer Center, stands out results within the ranges: a) Dose to the center of the target (RDS/Institution): 0,95-1,05; b) Treated volumen (Measured/Institution): 0,75 - 1,05; c) Ratio of measure treated volume to target volume: 1,00 - 2,00; and d) Minimum dose to target (Minimum dose/Prescription dose): >0,90. It concludes that the DIS is important for the good decision making on the radiological safety of the patients dealt with stereotactic radiosurgery. (author)

  20. Assessment of influence of OSL dosimeters in the skin dose in radiotherapy: study for Monte Carlo simulation; Avaliacao da influencia de dosimetros OSL na dose na pele em radioterapia: estudo por simulacao Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, Franciely F.; Nicolucci, Patricia, E-mail: franschuch@yahoo.com.br [Universidade de Sao Paulo (USP), Ribeiraoo Preto, SP (Brazil)

    2017-11-01

    The interest in optically stimulated luminescence (OSL) dosimetry materials is growing due to its potential use in quality control in Radiotherapy. The use of these dosimeters for in vivo dosimetry, however, may influence the dose to the skin and deeper tissues in the patient. The goal of this study is to evaluate the influence of the OSL Al{sub 2}O{sub 3} material in dose deposited in the skin and deep in Radiotherapy. Monte Carlo simulation is used to evaluate this purpose when OSL dosimeters of Al{sub 2}O{sub 3} are positioned on the skin surface of the patient. Percentage depth dose curves for clinical beams of 6 and 10 MV were simulated with and without the presence of the dosimeter on the surface of a water phantom. The results showed a decrease of doses in regions close to the surface of the skin. In the build-up region, the maximum decreases of dose produced by the presence of the dosimeters were 52,5% and 47,5% for the 6 and 10 MV beams, respectively. After the build-up region, there are not significant changes in the doses for any of the used beams. The differences of doses found are due to the influence of the dosimetric material on the relative fluence of electrons near the end surface of the dosimeter. Thus, the results showed that the presence of the dosimetric material on the surface interferes on the skin dose. However, these dosimeters do not cause dose variations in depths of clinical interest, allowing its application in routine in vivo dosimetry in Radiotherapy. (author)

  1. The dose dependency of the over-dispersion of quartz OSL single grain dose distributions

    International Nuclear Information System (INIS)

    Thomsen, Kristina J.; Murray, Andrew; Jain, Mayank

    2012-01-01

    The use of single grain quartz OSL dating has become widespread over the past decade, particularly with application to samples likely to have been incompletely bleached before burial. By reducing the aliquot size to a single grain the probability of identifying the grain population most likely to have been well-bleached at deposition is maximised and thus the accuracy with which the equivalent dose can be determined is – at least in principle – improved. However, analysis of single grain dose distributions requires knowledge of the dispersion of the well-bleached part of the dose distribution. This can be estimated by measurement of a suitable analogue, e.g. a well-bleached aeolian sample, but this requires such an analogue to be available, and in addition the assumptions that the sample is in fact a) well-bleached, and b) has a similar dose rate heterogeneity to the fossil deposit. Finally, it is an implicit assumption in such analysis that any over-dispersion is not significantly dose dependent. In this study we have undertaken laboratory investigations of the dose dependency of over-dispersion using a well-bleached modern sample with an average measured dose of 36 ± 3 mGy. This sample was prepared as heated (750 °C for 1 h), bleached and untreated portions which were then given uniform gamma doses ranging from 100 mGy to 208 Gy. We show that for these samples the relative laboratory over-dispersion is not constant as a function of dose and that the over-dispersion is smaller in heated samples. We also show that the dim grains in the distributions have a greater over-dispersion than the bright grains, implying that insensitive samples will have greater values of over-dispersion than sensitive samples.

  2. Evaluation of aluminum oxide dosimeters using OSL technique in dosimetry of clinical photon beams on volumetric modulated arc treatment

    International Nuclear Information System (INIS)

    Villani, Daniel

    2017-01-01

    Treatment using Volumetric Modulated Arc Radiation Therapy is the most modern modality of conformational radiotherapy so that, with the overlapping of several fields, the dose distributions provide a perfect conformation to the tumor, reducing the probability of complications in adjacent normal tissues. In this sense, many efforts are being invested to improve dose distribution compliance as well as the integration of imaging techniques for tumor screening and correction of inter and intrafraction variations. To this end, an intensive monitoring of the quality of the processes and a quality assurance program are fundamental for patient safety and compliance with current legislation; besides the use of different dosimetry methodologies for intercomparison and validation of the results. The aim of this study is to evaluate and compare the performance of aluminum oxide (Al_2O_3:C) OSL dosimeters manufactured by Landauer Inc. with those produced by Rexon™ in the dosimetry of high energy photon clinical bundles used in Volumetric Modulated Arc Therapy - (VMAT) using different simulating objects. The dosimeters were characterized for gamma radiation of the "6"0Co and for clinical photon beams of 6 MV typical of treatments by VMAT under conditions of electronic equilibrium and maximum dose respectively. Performance tests of the TL and OSL readers used and repeatability of the samples were evaluated. After all tests, the dosimeters were irradiated in the simulation of different radiotherapy treatments by VMAT and their responses compared to the planning system. All types of dosimeters presented satisfactory results in verifying the doses of this type of planning simulation. The Al_2O_3:C dosimeters presented compatible results and validated by the other dosimeters and ionization chamber. Regarding the best technique, the OSL InLight commercial system presents greater practicality and versatility for use and application in the clinical routine. (author)

  3. Online fibre optic OSL in vivo dosimetry for quality assurance of external beam radiation therapy treatments: The ANR-TECSAN Codofer Project

    International Nuclear Information System (INIS)

    Magne, S.; Ferdinand, P.; De Carlan, L.; Bridier, A.; Isambert, A.; Hugon, R.; Guillon, J.

    2010-01-01

    The Codofer Project (2007-2009), led under the ANR-TECSAN Call, was coordinated by CEA LIST, in partnership with IGR and the Fimel company. The aim of the project was to design and test both metrologically and in clinical conditions OSL optical fiber sensors dedicated to in vivo dosimetry during external beam radiation therapy treatment with high-energy electrons. This study, combined with the results of clinical tests obtained within the European Project Maestro, has demonstrated the advantages of OSL/FO dosimetry for providing quality assurance of treatments. However, the French market for dosimetry has greatly changed as a result of the rules decreed by the French government in 2007. The OSL/FO product is now targeted for other treatment modalities lacking suitable dosimeters (ANR-INTRADOSE Project [2009-2011]). (authors)

  4. Application of pulsed OSL to the separation of the luminescence components from a mixed quartz/feldspar sample

    DEFF Research Database (Denmark)

    Denby, Phil M.; Bøtter-Jensen, L.; Murray, A.S.

    2006-01-01

    with a feldspar signal. We have developed instrumentation for the study of high-speed pulse stimulated OSL. Our system uses the standard blue/IR LED stimulation unit of a Riso reader (allowing stimulation pulses down to 1-2 mu s duration) and can thus be applied to the routine analysis of samples. Using...... that counts are only accumulated during a windowed period, reduces the feldspar signal to 1.6% of its original value relative to that of the quartz. (c) 2006 Elsevier Ltd. All rights reserved....

  5. An investigation of coseismic OSL / TL time zeroing of quartz gouge based on low- to high-velocity friction experiments

    Science.gov (United States)

    Akasegawa, K.; Oohashi, K.; Hasebe, N.; Miura, K.

    2016-12-01

    To determine an age of coseismic event of an active fault, we generally examine crosscutting relationship between faults and overlying strata by trenching. However, we could not apply this method in case there are no overlying young strata in the vicinity of the fault zones. The alternative is a dating of fault zone materials whose age experienced resetting with seismic fault slip (for example, the ESR method;. Ikeya et al,1982; the OSL and TL methods). The idea behinds to the OSL (optically stimulated luminescence) and TL (thermoluminescence) dating methods for a determination of paleo-earthquake event is the accumulated natural radiation damage becomes to zero (time zeroing) by the frictional heating and grinding. However, physical and geological conditions required to induce time zeroing is not well understood because there is only few experimental investigations under the limited conditions (Hiraga et al,2004;. Kim et al, 2014) . In this study, we conduct low- to high-velocity friction experiments using quartz gouge under various experimental conditions (e.g., normal stress, displacement, moisture content) to establish an empirical relationship and physical and geological conditions of coseismic OSL time zeroing. In this experiment, we carry out the friction experiments using quartz in Tsushigawa granite taken from the east wall of the Nojima fault Ogura trench site, which was excavated in 2015. Samples were taken from the most distant position from the fault in the trench site. The samples were clashed using a mortar and sieved to a grain size of treatment. The residual is user for the friction experiments after having known radiation dose using an artificial gamma-ray source. In this presentation, we show results of the friction experiments and dating of the quartz gouge and discuss physical and geological conditions of OSL time zeroing. References Okumura, T., and Shitaoka, Y., 2011. Engineering Geology of Japan, No. 1, 5-17. Hiraga, S., Yoshimoto, A., and

  6. Dating recent floodplain sediments in the Hawkesbury-Nepean River system, eastern Australia using single-grain quartz OSL

    DEFF Research Database (Denmark)

    Sim, Anna K.; Thomsen, Kristina Jørkov; Murray, K.J.

    2014-01-01

    Two fluvial sediment cores taken from a floodplain of the Hawkesbury-Nepean River system in the Sydney region, eastern Australia are dated using Optically Stimulated Luminescence (OSL) to provide a reliable chronology essential for the management and planning of water resources. Nine charcoal 14C...... in an average apparent age overestimation of ~200 years, which is significant for these samples, but negligible for sediments older than a few thousand years. The intention is that the chronology obtained in this study will be used in conjunction with a proxy flood record, derived from floodplain sediments...

  7. Testing the accuracy of a Bayesian central-dose model for single-grain OSL, using known-age samples

    DEFF Research Database (Denmark)

    Guerin, Guillaume; Combès, Benoit; Lahaye, Christelle

    2015-01-01

    on multi-grain OSL age estimates, these samples are presumed to have been both well-bleached at burial, and unaffected by mixing after deposition. Two ways of estimating single-grain ages are then compared: the standard approach on the one hand, consisting of applying the Central Age Model to De values...... for well-bleached samples; (ii) dose recovery experiments do not seem to be a very reliable tool to estimate the accuracy of a SAR measurement protocol for age determination....

  8. Optically stimulated luminescence (OSL) from Ag-doped Li{sub 2}B{sub 4}O{sub 7} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kananen, B.E.; Maniego, E.S.; Golden, E.M.; Giles, N.C.; McClory, J.W. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, OH 45433 (United States); Adamiv, V.T.; Burak, Ya.V. [Vlokh Institute of Physical Optics, Dragomanov 23, L’viv 79005 (Ukraine); Halliburton, L.E., E-mail: Larry.Halliburton@mail.wvu.edu [Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506 (United States)

    2016-09-15

    Optically stimulated luminescence (CW-OSL) is observed from Ag-doped lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) crystals. Photoluminescence, optical absorption, and electron paramagnetic resonance (EPR) are used to identify the defects participating in the OSL process. As-grown crystals have Ag{sup +} ions substituting for Li{sup +} ions. They also have Ag{sup +} ions occupying interstitial sites. During a room-temperature exposure to ionizing radiation, holes are trapped at the Ag{sup +} ions that replace Li{sup +} ions and electrons are trapped at the interstitial Ag{sup +} ions, i.e., the radiation forms Ag{sup 2+} (4d{sup 9}) ions and Ag{sup 0} (4d{sup 10}5s{sup 1}) atoms. These Ag{sup 2+} and Ag{sup 0} centers have characteristic EPR spectra. The Ag{sup 0} centers also have a broad optical absorption band peaking near 370 nm. An OSL response is observed when the stimulation wavelength overlaps this absorption band. Specifically, stimulation with 400 nm light produces an intense OSL response when emission is monitored near 270 nm. Electrons optically released from the Ag{sup 0} centers recombine with holes trapped at Ag{sup 2+} ions to produce the ultraviolet emission. The OSL response is progressively smaller as the stimulation light is moved to longer wavelengths (i.e., away from the 370 nm peak of the absorption band of the Ag{sup 0} electron traps). Oxygen vacancies are also present in the Ag-doped Li{sub 2}B{sub 4}O{sub 7} crystals, and their role in the OSL process as a secondary relatively short-lived electron trap is described.

  9. OSL-SAR dating of sediments from Brazilian aeolian system: Dama Branca, Rio de Janeiro, morphodynamic study

    International Nuclear Information System (INIS)

    Carmo, Lucas S. do; Watanabe, Shigueo; DeWitt, Regina

    2017-01-01

    It has been reported that the formation and stabilization of coastal dune fields in Brazil have a dependence on the climate changes and Relative Sea Level (RSL) variations. A few topics regarding the morphodynamics of coastal aeolian systems in Brazil can be the RSL variations in the Holocene and weather conditions. In this work, a dune field known as 'Dama Branca', located in the town of Cabo Frio, Rio de Janeiro, has been studied to understand its formation and stabilization. Dating by trapped charge dating techniques as Optically Stimulated Luminescence (OSL) using the Single Aliquot Regenerative protocol (SAR), help to understand the formation and dynamics of aeolian systems in Brazil. Samples from a dune were collected from different heights and points for dating. The results obtained by OSL-SAR showed that ages decrease as the height from the dune base increase and older samples are found in deeper horizontal positions. The ages for the base of the studied dunes indicated that its stabilization occurred during the recess of the sea level. (author)

  10. OSL-SAR dating of sediments from Brazilian aeolian system: Dama Branca, Rio de Janeiro, morphodynamic study

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Lucas S. do; Watanabe, Shigueo, E-mail: lsatiro@usp.br, E-mail: lacifid@if.usp.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); DeWitt, Regina, E-mail: dewittr@ecu.edu [East Carolina University (ECU), Greenville, NC (United States)

    2017-07-01

    It has been reported that the formation and stabilization of coastal dune fields in Brazil have a dependence on the climate changes and Relative Sea Level (RSL) variations. A few topics regarding the morphodynamics of coastal aeolian systems in Brazil can be the RSL variations in the Holocene and weather conditions. In this work, a dune field known as 'Dama Branca', located in the town of Cabo Frio, Rio de Janeiro, has been studied to understand its formation and stabilization. Dating by trapped charge dating techniques as Optically Stimulated Luminescence (OSL) using the Single Aliquot Regenerative protocol (SAR), help to understand the formation and dynamics of aeolian systems in Brazil. Samples from a dune were collected from different heights and points for dating. The results obtained by OSL-SAR showed that ages decrease as the height from the dune base increase and older samples are found in deeper horizontal positions. The ages for the base of the studied dunes indicated that its stabilization occurred during the recess of the sea level. (author)

  11. A primary assessment of a daybreak 2200 OSL reader using fine grain quartz and CaSO4:Tm TLD

    International Nuclear Information System (INIS)

    Zhang Keqi; Chen Jie; Lu Yanchou; Wang Changsheng; Yang Chuancheng

    2007-01-01

    Daybreak 2200 OSL readers are widely used for luminescence dating applications. As the sample irradiation and illumination may affect discs in adjacent positions, it is critical to confirm that these factors do not introduce significant systematic errors. Effects of cross-irradiation and cross-bleaching were examined and quantified using fine-grain quartz and highly sensitive CaSO 4 :Tm dosimeters, and the irradiation offset time was measured. The cross-bleaching effect on adjacent aliquots is non-linear with no more than 15% OSL signal reduction following 10ks illumination with the power of blue LED being at 95% maximum. But at positions other than the nearest neighboring sample, almost no effect of cross-bleaching was found. The cross-talk dose, even to the nearest samples, was about 0.02% of the applied dose, and it decreased with increasing distance from the source. Offset time of the built-in Beta source shutter is 0.22 s, which can be neglected in regular dating, and leak dose of the source can be ignored as well. Finally, measurement consistency at Position 0.5, 10, ..... and 55 of the sample tray is better than 3% in relative standard deviation. (authors)

  12. Luminescence dating of Pleistocene alluvial sediments affected by the Alhama de Murcia fault (eastern Betics, Spain) – a comparison between OSL, IRSL and post-IRIRSL ages

    DEFF Research Database (Denmark)

    Sohbati, Reza; Murray, Andrew S.; Buylaert, Jan-Pieter

    2012-01-01

    The ages of nine alluvial units, identified by the integration of data obtained from five trenches at the southern termination of the Alhama de Murcia Fault (AMF) (eastern Betics, Spain), are constrained using luminescence dating based on the Optically Stimulated Luminescence (OSL) from quartz...

  13. Persistent luminescence, TL and OSL characterization of beta irradiated SrAl2O4:Eu2+, Dy3+ combustion synthesized phosphor

    International Nuclear Information System (INIS)

    Zúñiga-Rivera, N.J.; García, R.; Rodríguez-Mijangos, R.; Chernov, V.; Meléndrez, R.; Pedroza-Montero, M.; Barboza-Flores, M.

    2014-01-01

    The persistent luminescence (PLUM), thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of strontium aluminates co-doped with Eu +2 and Dy +3 exposed to beta radiation is reported. The phosphor was synthesized by the combustion synthesis method employing a highly exothermic redox reaction between the metal nitrates [Al(NO 3 ) 3 , Sr(NO 3 ) 2 , Eu(NO 3 ) 3 and Dy(NO 3 ) 3 ] and organic fuel carbohydrazide (CH 6 N 4 O). The long decay PLUM emission, TL and OSL were measured as a function of beta radiation dose. A wide emission band centered at 510 nm (green) related to Eu 2+ ions and lattice defects were observed for the synthesized samples. The presence of a variety of defects and aggregates were responsible for the observed broad 100 °C peaked TL glow curve of the irradiated sample which is composed of several overlapped TL peaks. The existence of multiple trapping levels, with different trapping/detrapping probabilities, is behind the particular features for the PLUM, TL and OSL emissions. We conclude that in the SrAl 2 O 4 :Eu 2+ , Dy 3+ phosphors, the low temperature TL peaked around 30–75 °C is responsible for the PLUM emission and those around 100 °C were related to very stable trapping states which provide suitable radiation storage properties to be used as a PLUM/TL/OSL radiation phosphor

  14. High-resolution OSL chronology of a sediment core from Lake Nam Co on the southern Tibetan Plateau: Comparison with radiocarbon dating

    Science.gov (United States)

    Long, Hao; Shen, Ji; Haberzettl, Torsten; Fuchs, Markus; Frechen, Manfred; Wang, Junbo

    2013-04-01

    Numerous studies on lake sediment cores from the Tibetan Plateau aimed to reconstruct spatial and temporal changes of the late Glacial and Holocene monsoon variations, which are characterized by fluctuations in precipitation and expansion of monsoonal air masses across the Plateau. Accurate and reliable dating of lacustrine deposits is of crucial importance in both the reconstruction of palaeolake and palaeoclimate evolution and the understanding of the mechanisms for climate changes, especially abrupt changes of regional-hemispheric hydrological circulation. Radiocarbon dating is the most commonly used method for establishing chronologies of lake sediments. However, 14C dating of such sediments could be problematic due to the lack of organic matter or a reservoir effect, which appears common in radiocarbon dating of lacustrine sediments from the Tibetan Plateau. In this study, ca. 10.5 m long core (NC core) was retrieved from the water depth of 93 m at Nam Co Lake, which is the second largest saline lake in China, located on the southern Tibetan Plateau. For this core, high-resolution samples (23 samples) were obtained for optically stimulated luminescence (OSL) dating. Quartz of fine-grain (4-11 μm) fraction were extracted from this samples for OSL dating, which is compared with the 14C chronology of NC core based on accelerator mass spectrometry (AMS) dating of bulk organic matter of 22 samples. The sample from the top of NC core was dated to approximate zero age, indicating the sediments bleached well before deposition. Luminescence behaviors of the study samples further confirmed the robustness of OSL ages. Comparison between OSL and 14C ages suggested that: (1) two kinds of ages are in agreement within error from top to 1.8 m, (2) from 1.8 m to the base of NC core, the 14C ages show a general trend to ca. 4 ka higher ages than the OSL ages. Although 14C dating overestimate the ages from 1.8 m to base, they still show the general trend in sedimentation rate

  15. Estimation of identification limit for a small-type OSL dosimeter on the medical images by measurement of X-ray spectra.

    Science.gov (United States)

    Takegami, Kazuki; Hayashi, Hiroaki; Okino, Hiroki; Kimoto, Natsumi; Maehata, Itsumi; Kanazawa, Yuki; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

    2016-07-01

    Our aim in this study is to derive an identification limit on a dosimeter for not disturbing a medical image when patients wear a small-type optically stimulated luminescence (OSL) dosimeter on their bodies during X-ray diagnostic imaging. For evaluation of the detection limit based on an analysis of X-ray spectra, we propose a new quantitative identification method. We performed experiments for which we used diagnostic X-ray equipment, a soft-tissue-equivalent phantom (1-20 cm), and a CdTe X-ray spectrometer assuming one pixel of the X-ray imaging detector. Then, with the following two experimental settings, corresponding X-ray spectra were measured with 40-120 kVp and 0.5-1000 mAs at a source-to-detector distance of 100 cm: (1) X-rays penetrating a soft-tissue-equivalent phantom with the OSL dosimeter attached directly on the phantom, and (2) X-rays penetrating only the soft-tissue-equivalent phantom. Next, the energy fluence and errors in the fluence were calculated from the spectra. When the energy fluence with errors concerning these two experimental conditions was estimated to be indistinctive, we defined the condition as the OSL dosimeter not being identified on the X-ray image. Based on our analysis, we determined the identification limit of the dosimeter. We then compared our results with those for the general irradiation conditions used in clinics. We found that the OSL dosimeter could not be identified under the irradiation conditions of abdominal and chest radiography, namely, one can apply the OSL dosimeter to measurement of the exposure dose in the irradiation field of X-rays without disturbing medical images.

  16. Sistema computacional para dosimetria de nêutrons e fótons baseado em métodos estocásticos aplicado a radioterapia e radiologia

    Directory of Open Access Journals (Sweden)

    Bruno Machado Trindade

    2011-04-01

    Full Text Available OBJETIVO: Este artigo mostra um procedimento de conversão de imagens de tomografia computadorizada ou de ressonância magnética em modelo de voxels tridimensional para fim de dosimetria. Este modelo é uma representação personalizada do paciente que pode ser usado na simulação, via código MCNP (Monte Carlo N-Particle, de transporte de partículas nucleares, reproduzindo o processo estocástico de interação de partículas nucleares com os tecidos humanos. MATERIAIS E MÉTODOS: O sistema computacional desenvolvido, denominado SISCODES, é uma ferramenta para planejamento computacional tridimensional de tratamentos radioterápicos ou procedimentos radiológicos. Partindo de imagens tomográficas do paciente, o plano de tratamento é modelado e simulado. São então mostradas as doses absorvidas, por meio de curvas de isodoses superpostas ao modelo. O SISCODES acopla o modelo tridimensional ao código MCNP5, que simula o protocolo de exposição à radiação ionizante. RESULTADOS: O SISCODES vem sendo utilizado no grupo de pesquisa NRI/CNPq na criação de modelos de voxels antropomórficos e antropométricos que são acoplados ao código MCNP para modelar braquiterapias e teleterapias aplicadas a tumores em pulmões, pelve, coluna, cabeça, pescoço, e outros. Os módulos atualmente desenvolvidos no SISCODES são apresentados junto com casos exemplos de planejamento radioterápico. CONCLUSÃO: O SISCODES provê de maneira rápida a criação de modelos de voxels personalizados de qualquer paciente que podem ser usados em simulações por códigos estocásticos tipo MCNP. A combinação da simulação via MCNP com um modelo personalizado do paciente traz grandes melhorias na dosimetria de tratamentos radioterápicos.

  17. Personal monitoring services available at Institute for Radiation Protection of ENEA; Il servizo di dosimetria personale dell'Istituto per la Radioprotezione dell'ENEA

    Energy Technology Data Exchange (ETDEWEB)

    Fantuzzi, E.; Bonarelli, T. [ENEA Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente

    1999-07-01

    Personnel monitoring provides the means to measure and record the radiation doses received by individual workers. The ionising radiation decree (230/95) set out the circumstances when the assessment and recording of person's exposure is legally required. Many employers issue dosemeters to staff even though there is no legal requirement to do so. This may be part of a quality assurance programme or as a reassurance measure. Dosemeter readings will serve to ensure compliance with legal dose limits and assure the employer that radiation exposure is as low as reasonably achievable. The ENEA (National Agency for New Technology, Energy and the Environment) IRP (Institute for Radiation Protection) individual monitoring service has been running for over 30 years. It offers personnel dosemeters which are based on its expertise and backed up by continual research and development. The report provides details of the dosemeters in use at IRP enable to decide which ones most suit the needs and shows IMS's organisation, customer and communications, dose reports form and administrative items. A short mention of future development will also be given. [Italian] La dosimetria individuale fornisce gli strumenti per misurare e registrare le dosi da radiazioni ionizzanti ricevute dai lavoratori esposti. Il decreto legislativo 230/95 stabilisce le circostanze in cui il monitoraggio individuale e' legalmente richiesto. Molti datori di lavoro forniscono dosimetri individuali anche quando non vi e' una richiesta legale spesso per seguire le regole di un programma di assicurazione di qualita' relativo alla radioprotezione o per ottenere una conferma che il principio ALARA sia soddisfatto. Il servzio di dosimetria personale dell'Istituto per la Radioprotezione dell'ENEA e' attivo da oltre 30 anni e offre dosimetri sviluppati sulla propria esperienza nelle tecniche dosimetriche che vengono continuamente aggiornati e adeguati rispecchiando lo stato dell

  18. Stability of fine-grained TT-OSL and post-IR IRSL signals from a c. 1 Ma sequence of aeolian and lacustrine deposits from the Nihewan Basin (northern China)

    DEFF Research Database (Denmark)

    Liu, Jinfeng; Murray, Andrew Sean; Buylaert, Jan-Pieter

    2016-01-01

    We tested the suitability of the fine-grained quartz (4–11 μm) Optical Stimulated Luminescence (OSL) and thermally-transferred OSL (TT-OSL), and the fine-grained polymineral (4–11 μm) post-infrared IRSL (post-IR IRSL or pIRIR) signals for dating samples from aeolian-lacustrine deposits from...... accurate ones; nevertheless, these ages provide the first long series absolute chronology for study of local palaeolithic and geomorphic evolution history aside from the  magnetostratigraphical results available before this research....

  19. Single-grain OSL dating of Early Middle Palaeolithic deposits at Cuesta de la Bajada, Ebro Basin, Spain

    Science.gov (United States)

    Arnold, Lee; Demuro, Martina; Santonja, Manuel; Perez-Gonzalez, Alfredo; Pares, Josep

    2013-04-01

    The open-air site of Cuesta de la Bajada comprises a 2-2.5 m-thick sequence of fluvial-lacustrine sediments inset into the +50-60 m terrace deposits preserved along the south-eastern margins of the Alfambra river valley, Teruel, Spain. The main archaeological horizons lie ~20 m above the present-day river level and consists of an upward-fining sequence of massive fluvial silts and fine sands with dispersed gravels, detritic marls and shales that collectively overlie a series of planar bedded fluvial gravels. These units have yielded ~3000 lithic artefacts displaying reduction techniques characteristic of an early Middle Palaeolithic techno-complex, as well as a multitude of faunal remains indicative of a late Middle Pleistocene origin. The paucity of open-air Palaeolithic sites in the interior eastern sector of the Iberian Peninsula, and the relatively low number of documented early Middle Palaeolithic archives in this region, means that Cuesta de la Bajada is of key importance for understanding the coexistence/transition of Iberian Acheulean and Mousterian techno-complexes during the Middle Pleistocene period. Establishing reliable absolute chronologies at Cuesta de la Bajada remains essential for understanding the regional significance of this site. In an attempt to redress the existing chronological uncertainty we are undertaking an interdisciplinary dating study of the Middle Palaeolithic deposits using OSL dating, ESR/U-series dating of teeth and ESR dating of sedimentary quartz. Here we present results obtained using quartz single-grain OSL dating of 4 samples collected from a 7 m vertical profile bracketing the archaeological horizons. 2 samples were collected from the archaeology-bearing silt and fine sand horizons, while the remaining samples were obtained from well-bedded fine-sands and silts 3.5 m above and 3 m below the main excavation. The measured quartz grains are characterised by relatively bright OSL signals and typically display dose

  20. Existence of a common growth curve for silt-sized quartz OSL of loess from different continents

    International Nuclear Information System (INIS)

    Lai Zhongping; Brueckner, Helmut; Zoeller, Ludwig; Fuelling, Alexander

    2007-01-01

    Recent publications revealed different opinions regarding the existence of a common growth curve (CGC) for OSL of quartz. In the current study, 18 loess samples were collected from four continents (Asia, America, Africa, and Europe) in order to further examine this issue. Except the three samples from Chile in South America, 15 samples display similar dose-response curves up to a regeneration dose of 200 Gy using the SAR protocol, suggesting the existence of a global CGC for loess from different continents. For samples with equivalent doses (D e ) from ∼10 to ∼170Gy, the D e s determined by the CGC are in good agreement with the D e s by the SAR protocol. The Chilean samples posses a growth curve that differs from the CGC, showing much lower saturation doses. We suggest that it may be due to contamination with heavy minerals

  1. A low-cost personal dosemeter based on optically stimulated luminescence (OSL) of common household salt (NaCl)

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2016-01-01

    Salt represents a radiation sensitive material that can be used for dosimetry. The objective of this experimental study was to test a low-cost salt dosemeter that was designed for personnel that are not radiation workers, but can operate in low probability events resulting in a serious external radiation exposure. The dosemeter is based on use of optically stimulated luminescence (OSL) of a common household salt. Attention was concentrated on its energy and angular responses. The dosemeter was fixed to the ICRU slab phantom and irradiated by photons of reference radiation qualities (ISO 4037-1) with mean energies between 33 and 1250 keV. Angular response was investigated for angles of incidence from 0° to 80° for radiation qualities of N-150 (∼118 keV) and S-Cs (∼662 keV). Single-Aliquot Regenerative-dose analytical protocol was employed for dose reconstruction. The results were evaluated with respect to H_p(10) measurement. The salt dosemeter can provide reliable or reasonably conservative H_p(10) estimates in radiation fields where photon energies > 100 keV predominate, radiation incidence angles are from 0° to 80° and also for rotational geometry. Furthermore, a personal dose reconstruction trial was demonstrated. Relative deviation between the measured and reference H_p(10) values was 5.5%. A practical disadvantage of the method is the more demanding analytical protocol. - Highlights: • Common salt has a considerable potential for dosimetry based on use of OSL. • A simple salt personal dosemeter was designed and tested. • Photon energy and angular responses were satisfactory for purposes of accidental dosimetry. • Dose reconstruction trial proved the potential for reliable estimate of personal doses.

  2. SU-F-T-327: Total Body Irradiation In-Vivo Dose Measurements Using Optically Stimulated Luminescence (OSL) NanoDots and Farmer Type Ion Chamber

    International Nuclear Information System (INIS)

    Kaur, H; Kumar, S; Sarkar, B; Ganesh, T; Giri, U; Jassal, K; Rathinamuthu, S; Gulia, G; Gopal, V; Mohanti, B; Munshi, A

    2016-01-01

    Purpose: This study was performed to analyze the agreement between optically stimulated luminescence (OSL) nanoDots measured doses and 0.6 cc Farmer type ionization chamber measured doses during total body irradiation (TBI). Methods: In-vivo dose measurements using OSL nanoDots and Farmer chamber were done in a total of twelve patients who received TBI at our center by bilateral parallel-opposed beams technique. In this technique, the patient is kept inside the TBI box which is filled with rice bags and irradiated using two bilateral parallel opposed beams of 40×40 cm"2 size with 45° collimator rotation at an SSD of 333.5 cm in an Elekta Synergy linear accelerator. All patients received a dose of 2 Gy in single fraction as conditioning regimen. The beams were equally weighted at the midplane of the box. The nanoDots were placed over forehead, right and left neck, right and left lung, umbilicus, right and left abdomen, medial part of thigh, knee and toe. A 0.6 cc Farmer chamber was placed in between the thighs of the patient. Measured doses are reported along with the statistical comparisons using paired sample t-test. Results: For the above sites the mean doses were 212.2±21.1, 218.2±7.6, 218.7±9.3, 215.6±9.5, 217.5±11.5, 214.5±7.7, 218.3±6.8, 221.5±15, 229.1±11.0, 220.5±7.7 and 223.3±5.1 cGy respectively. For all OSL measurements the mean dose was 218.6±11.8 cGy. Farmer chamber measurements yielded a mean dose of 208.8±15.6 cGy. Statistical analysis revealed that there was no significant difference between OSL measured doses in forehead, right and left neck, right and left lung, umbilicus, right and left abdomen and toe and Farmer chamber measured doses (0.72≤p≤0.06). However the mean OSL doses at thigh and knee were statistically different (p<0.05) from the Farmer chamber measurements. Conclusion: OSL measurements were found to be in agreement with Farmer type ionization chamber measurements in in-vivo dosimetry of TBI.

  3. SU-F-T-327: Total Body Irradiation In-Vivo Dose Measurements Using Optically Stimulated Luminescence (OSL) NanoDots and Farmer Type Ion Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, H; Kumar, S; Sarkar, B; Ganesh, T; Giri, U; Jassal, K; Rathinamuthu, S; Gulia, G; Gopal, V; Mohanti, B; Munshi, A [Fortis Memorial Research Institute, Gurgaon, Haryana (India)

    2016-06-15

    Purpose: This study was performed to analyze the agreement between optically stimulated luminescence (OSL) nanoDots measured doses and 0.6 cc Farmer type ionization chamber measured doses during total body irradiation (TBI). Methods: In-vivo dose measurements using OSL nanoDots and Farmer chamber were done in a total of twelve patients who received TBI at our center by bilateral parallel-opposed beams technique. In this technique, the patient is kept inside the TBI box which is filled with rice bags and irradiated using two bilateral parallel opposed beams of 40×40 cm{sup 2} size with 45° collimator rotation at an SSD of 333.5 cm in an Elekta Synergy linear accelerator. All patients received a dose of 2 Gy in single fraction as conditioning regimen. The beams were equally weighted at the midplane of the box. The nanoDots were placed over forehead, right and left neck, right and left lung, umbilicus, right and left abdomen, medial part of thigh, knee and toe. A 0.6 cc Farmer chamber was placed in between the thighs of the patient. Measured doses are reported along with the statistical comparisons using paired sample t-test. Results: For the above sites the mean doses were 212.2±21.1, 218.2±7.6, 218.7±9.3, 215.6±9.5, 217.5±11.5, 214.5±7.7, 218.3±6.8, 221.5±15, 229.1±11.0, 220.5±7.7 and 223.3±5.1 cGy respectively. For all OSL measurements the mean dose was 218.6±11.8 cGy. Farmer chamber measurements yielded a mean dose of 208.8±15.6 cGy. Statistical analysis revealed that there was no significant difference between OSL measured doses in forehead, right and left neck, right and left lung, umbilicus, right and left abdomen and toe and Farmer chamber measured doses (0.72≤p≤0.06). However the mean OSL doses at thigh and knee were statistically different (p<0.05) from the Farmer chamber measurements. Conclusion: OSL measurements were found to be in agreement with Farmer type ionization chamber measurements in in-vivo dosimetry of TBI.

  4. High resolution OSL and post-IR IRSL dating of the last interglacialeglacial cycle at the Sanbahuo loess site (northeastern China)

    DEFF Research Database (Denmark)

    Yi, Shuangwen; Buylaert, Jan-Pieter; Murray, Andrew

    2015-01-01

    Northeastern China is located in the East Asian monsoon region; it is sensitive to both high and low latitude global climate systems. Loess deposits in the region have considerable potential as sensitive archives of past climate changes. However, research into loess deposition and climate change...... to have been a period of fast loess deposition at ~62 ka, perhaps indicative of winter monsoon intensification with a very cold and dry climate that lead to a serious desertification of dunefields in northeastern China. © 2015 Elsevier B.V. All rights reserved....... in this region is restricted by the lack of independent age control. In this study, coarse-grained quartz SAR OSL and K-feldspar post-IR infrared (IR) stimulated luminescence (post-IR IRSL; pIRIR290) methods have been used to date the Sanbahuo loess site in northeastern China. The quartz OSL characteristics...

  5. Comparative study of different Al_2O_3:C dosimeters using OSL technique for dosimetry on Volumetric Modulated Arc Radiotherapy Treatment (VMAT)

    International Nuclear Information System (INIS)

    Villani, Daniel; Campos, LetIcia L.; Mancini, Anselmo; Haddad, Cecilia M.K.

    2016-01-01

    In modern radiotherapy, the VMAT technique has become a successful treatment alternative. Due to its complexity, a quality assurance program must be established by evaluating, among other items, the dosimetric factors. This paper aims to compare the performance between the OSL aluminum oxide (Al_2O_3:C) nanoDot™ dosimeters (Inlight™ system) manufactured by Landauer Inc. and TLD-500 Al_2O_3:C dosimeters manufactured by Rexon™ for VMAT dosimetry using an anthropomorphic phantom. The results showed that both type of Al_2O_3:C dosimeters presented good repeatability and agreement between the doses measured and calculated by planning system. However, the need of sophisticated readers to OSL analysis of the TLD-500, turns it less practical for routine usage, comparing to Inlight™ system. (author)

  6. PIXE multivariate statistics and OSL investigation for the classification and dating of archaeological pottery excavated at Tell Al-Rawda site, Syria

    Energy Technology Data Exchange (ETDEWEB)

    Bakraji, E.H., E-mail: cscientificl@aec.org.sy [Archaeometry Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P. O. Box 6091, Damascus (Syrian Arab Republic); Rihawy, M.S. [Archaeometry Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P. O. Box 6091, Damascus (Syrian Arab Republic); Castel, C. [CNRS – Maison de l’Orient et de la Méditerranée, Laboratoire “Archéorient”, CNRS/Université Lumière-Lyon 2 (France); Abboud, R. [Archaeometry Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P. O. Box 6091, Damascus (Syrian Arab Republic)

    2015-03-15

    Highlights: •PIXE and OSL methods were used to classify and date pottery from Tell Al-Rawda site. •Three groups were classified using PIXE, which suggest different sources of the clay. •OSL was used for dating the site and the date found was consistent with typology. -- Abstract: Particle Induced X-ray Emission (PIXE) technique has been utilised to study 48 Syrian ancient pottery fragments taken from excavations at Tell Al-Rawda site. Eighteen elements (Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Ni, Zn, As, Br, Rb, Sr, Y, and Pb) were determined. The elements concentrations have been processed using two multivariate statistical methods, to classify the pottery where one main group and other two small groups were defined. In addition, four samples from different places on the site were subjected to optically stimulated luminescence (OSL) dating. The average age obtained using a single aliquot regeneration (SAR) protocol was found to be 4350 ± 240 year.

  7. Establishing a luminescence chronology for a palaeosol-loess profile at Tokaj (Hungary): A comparison of quartz OSL and polymineral IRSL signals

    DEFF Research Database (Denmark)

    Schatz, Ann-Kathrin; Buylaert, Jan-Pieter; Murray, Andrew

    2012-01-01

    We present a comparative study of quartz OSL, polymineral IRSL at low temperature (50 °C, IR50) and post-IR elevated temperature (290 °C) IRSL (pIRIR290) feldspar dating on nine samples from the Tokaj loess section in NE Hungary (SE Europe). Preheat plateau tests show a drop in quartz OSL De...... between 160 and 240 °C but above 240 °C a clear De plateau is present. Quartz OSL SAR is shown to be generally appropriate to these samples (recycling, recuperation) but a satisfactory dose recovery result was only obtained when a dose was added to a sample without any prior optical or thermal pre...... of the Tokaj loess has been deposited during MIS 3 (60–24 ka), with periods of soil formation occurring during the onset of MIS 3 (≥58 ka) and between about 35 and 25 ka. Our results also indicate episodic deposition of loess and varying, non-linear sedimentation rates during MIS 3. Proxy analyses...

  8. PIXE multivariate statistics and OSL investigation for the classification and dating of archaeological pottery excavated at Tell Al-Rawda site, Syria

    International Nuclear Information System (INIS)

    Bakraji, E.H.; Rihawy, M.S.; Castel, C.; Abboud, R.

    2015-01-01

    Highlights: •PIXE and OSL methods were used to classify and date pottery from Tell Al-Rawda site. •Three groups were classified using PIXE, which suggest different sources of the clay. •OSL was used for dating the site and the date found was consistent with typology. -- Abstract: Particle Induced X-ray Emission (PIXE) technique has been utilised to study 48 Syrian ancient pottery fragments taken from excavations at Tell Al-Rawda site. Eighteen elements (Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Ni, Zn, As, Br, Rb, Sr, Y, and Pb) were determined. The elements concentrations have been processed using two multivariate statistical methods, to classify the pottery where one main group and other two small groups were defined. In addition, four samples from different places on the site were subjected to optically stimulated luminescence (OSL) dating. The average age obtained using a single aliquot regeneration (SAR) protocol was found to be 4350 ± 240 year

  9. Sources of uncertainties in OSL dating of archaeological mortars: The case study of the Roman amphitheatre “Palais-Gallien” in Bordeaux

    International Nuclear Information System (INIS)

    Urbanova, P.; Hourcade, D.; Ney, C.; Guibert, P.

    2015-01-01

    Archaeological mortars are more convenient and much more representative for the chronology of buildings than brick or wood constructions that can be re-used from older buildings. Before dating unknown samples of mortars, further investigation of OSL from mortars is required and the most efficient methodology needs to be established. In this study we compared the ages obtained by OSL dating of quartz extracted from mortars of the Roman amphitheatre Palais-Gallien in Bordeaux with independent age information. Resetting of the OSL signal occurred during the preparation of mortar when grains of sand (quartz) were extracted and mixed with lime and water. The mortar was subsequently hidden from light by embedding within the structure which is the event to be dated. Various factors contribute to uncertainties in the age determination. The frequency of measured equivalent doses reveals a large scattering. Optical bleaching of certain grains can be partial due to the short duration of the exposure to light. We worked with the single grain technique in order to find and select the grains that were sufficiently exposed to daylight. To determine the average equivalent dose, we tried three different approaches: a calculation of an arithmetic mean and one following either the central age model or the 3-parameter minimum age model, the latter turned out to be the only relevant way to evaluate the experimental data. The proportion of grains included in the calculation of the average equivalent dose represents 2.7–4.7 % of the overall analysed grains. The results obtained for the three out of four samples are approaching the expected age, however, the minimum doses and the corresponding ages are significantly over-estimated in case of two samples. The studied material is very coarse, which causes heterogeneity of irradiation at the single grain scale, and contributes to a dispersion of equivalent doses. Different analytical methods (scanning electron microscopy with energy

  10. Investigation of the response characteristics of OSL albedo neutron dosimeters in a 241AmBe reference neutron field

    Science.gov (United States)

    Liamsuwan, T.; Wonglee, S.; Channuie, J.; Esoa, J.; Monthonwattana, S.

    2017-06-01

    The objective of this work was to systematically investigate the response characteristics of optically stimulated luminescence Albedo neutron (OSLN) dosimeters to ensure reliable personal dosimetry service provided by Thailand Institute of Nuclear Technology (TINT). Several batches of InLight® OSLN dosimeters were irradiated in a reference neutron field generated by the in-house 241AmBe neutron irradiator. The OSL signals were typically measured 24 hours after irradiation using the InLight® Auto 200 Reader. Based on known values of delivered neutron dose equivalent, the reading correction factor to be used by the reader was evaluated. Subsequently, batch homogeneity, dose linearity, lower limit of detection and fading of the OSLN dosimeters were examined. Batch homogeneity was evaluated to be 0.12 ± 0.05. The neutron dose response exhibited a linear relationship (R2=0.9974) within the detectable neutron dose equivalent range under test (0.4-3 mSv). For this neutron field, the lower limit of detection was between 0.2 and 0.4 mSv. Over different post-irradiation storage times of up to 180 days, the readings fluctuated within ±5%. Personal dosimetry based on the investigated OSLN dosimeter is considered to be reliable under similar neutron exposure conditions, i.e. similar neutron energy spectra and dose equivalent values.

  11. Stepped-irradiation SAR: A viable approach to circumvent OSL equivalent dose underestimation in last glacial loess of northwestern China

    International Nuclear Information System (INIS)

    Qin, J.T.; Zhou, L.P.

    2009-01-01

    The equivalent dose (D e ) obtained with the continuous irradiation SAR (CI-SAR) protocol for fine-grained quartz from loess of northwestern China is found to be lower than the expected value for samples older than 70 ka based on the regional stratigraphy. This is attributed to the difference in the response of the quartz to natural radiation and laboratory beta irradiation whose rates vary by ∼10 8 times. A stepped irradiation SAR protocol was employed to evaluate the influence of such a 'dose rate effect' on the equivalent dose determination. After investigating the effects of thermal treatment and 'unit-dose' on OSL signal and D e , we refined the stepped irradiation strategy with a 'unit-dose' of ∼25 Gy and successive thermal treatments at 250 deg. C for 10 s, and applied it to the SAR protocol. This stepped irradiation SAR (SI-SAR) protocol led to a 20%-70% increase in D e value for loess deposited during the early last glacial period.

  12. Aplicativo para dosimetria interna usando a distribuição biocinética de fótons baseada em imagens de medicina nuclear

    Directory of Open Access Journals (Sweden)

    Viriato Leal Neto

    2014-10-01

    Full Text Available Objetivo: Este artigo apresenta uma forma de se obterem estimativas de dose em pacientes submetidos a tratamentos radioterápicos a partir da análise das regiões de interesse em imagens de medicina nuclear. Materiais e Métodos: Foi desenvolvido o software denominado DoRadIo (Dosimetria das Radiações Ionizantes, que recebe as informações sobre os órgãos fontes e o órgão alvo e retorna resultados gráficos e numéricos. As imagens de medicina nuclear utilizadas foram obtidas de catálogos disponibilizados por físicos médicos. Nas simulações utilizaram-se modelos computacionais de exposição constituídos por fantomas de voxels acoplados ao código Monte Carlo EGSnrc. O software foi desenvolvido no Microsoft Visual Studio 2010 com o modelo de projeto Windows Presentation Foundation e a linguagem de programação C#. Resultados: Da aplicação das ferramentas foram obtidos: o arquivo para otimização das simulações Monte Carlo utilizando o EGSnrc, a organização e compactação dos resultados dosimétricos com todas as fontes, a seleção das regiões de interesse, a contagem da intensidade dos tons de cinza nas regiões de interesse, o arquivo das fontes ponderadas e, finalmente, todos os resultados gráficos e numéricos. Conclusão: A interface de usuários pode ser adaptada para uso em clínicas de medicina nuclear como ferramenta computacional auxiliar na estimativa da atividade administrada.

  13. Scientific production of the Radioprotection and Dosimetry Institute (IRD): preliminary bibliometric evaluation of the journal articles; Producao cientifica do Instituto de Radioprotecao e Dosimetria (IRD): avaliacao bibliometrica preliminar dos artigos de periodicos

    Energy Technology Data Exchange (ETDEWEB)

    Gusmao Pedrini, A de [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil); [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia; [Universidade Santa Ursula, Rio de Janeiro, RJ (Brazil). Centro de Ciencias Biologicas

    1994-12-31

    A total of 114 articles (1974-1991, this last year the most productive) in 28 periodicals were published. The periodical core production is made up of: Health Physics, Radiation Protection Dosimetry, Radioprotecao e Dosimetria, Radiologia Brasileira. 53% were written in cooperation with 33 institutions. The 155 authors and 376 authorship were mainly in collective and triple-authorship articles. Mean productivity/author was 2.8 articles which is lower than that of Price. The most productivity author produced 14 articles + 19 co-authors in 7 periodicals on environmental radiation protection while 88 authors produced 1 article. The productive elite (12 authors) accounted for 72 articles, 26% above the average according to Lotka, with 111 out of a total of 376 authorships in 20 periodicals. The elite forms an inter departmental communication network with authors who write about environmental, occupational and individual radiation protection. (author). 17 refs, 1 tab.

  14. Bioactivity characterization of 45S5 bioglass using TL, OSL and EPR: Comparison with the case of 58S sol-gel bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Polymeris, G.S., E-mail: gspolymeris@ankara.edu.tr [Ankara University, Institute of Nuclear Sciences, 06100 Beşevler, Ankara (Turkey); Giannoulatou, V. [Ankara University, Institute of Nuclear Sciences, 06100 Beşevler, Ankara (Turkey); Solid State Section, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kyriakidou, A. [Solid State Section, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Sfampa, I.K. [Nuclear Physics Laboratory, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Theodorou, G.S. [Solid State Section, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Şahiner, E.; Meriç, N. [Ankara University, Institute of Nuclear Sciences, 06100 Beşevler, Ankara (Turkey); Kitis, G. [Nuclear Physics Laboratory, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Paraskevopoulos, K.M. [Solid State Section, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2017-01-01

    The current work exploits the effective application of thermoluminescence (TL), optically stimulated luminescence (OSL) and the possibility of applying Electron Paramagnetic Resonance (EPR) for the discrimination between different bioactive responses in the case of the 45S5 bioactive glass (SiO{sub 2} 45, Na{sub 2}O 24.5, CaO 24.5, P{sub 2}O{sub 5} 6 in wt%), which was synthesized through melting process. These techniques are suggested mainly due to their low spectroscopic detection thresholds. The original 45S5 in grain size range of 20–40 μm was immersed in the Simulated Body Fluid (SBF) for various different immersion times ranging over one week. In this work the 110 °C TL peak, a specific OSL component and the EPR signal at g = 2.013 ascribed to oxygen hole center (OHC) are used due to their sensitivity to the different bioactive responses. For all luminescence and EPR components, the intensity plot versus immersion time yields sharp discontinuities, resulting in effective probes regarding the timescale for both the beginning as well as the end of the procedure of the crystalline HCAp formation respectively. On the contrary to the smooth decreasing pattern of both luminescence entities, the peak to peak amplitude of the EPR signal indicates an initial increase for the initial 16 min of immersion, followed by a further decrease throughout the immersion time duration. The discontinuities monitored for both sensitivity of TL, OSL and EPR, in conjunction with the discontinuities monitored for the sensitization of TL and OSL, when plotted versus immersion time, provide an individual time scale for each one of the chemical reactions involved in the five steps of the aforementioned procedure. According to the authors' best knowledge, scarce characterization techniques could provide this time scale frame, while it is the first time that such an application of OSL and EPR is attempted. Finally, the bioactive response of the 45S5 bioglass was compared with that

  15. Preliminary results of chronostratigraphic field work, OSL-dating and morphogenetic reconstruction of an alluvial apron at Alborz southern foothill, Damghan basin, Iran

    Science.gov (United States)

    Büdel, Christian; Fuchs, Markus; Majid Padashi, Seyed; Baumhauer, Roland

    2014-05-01

    Here we present preliminary results of a chronostratigraphic study of an alluvial fan in the Damghan Basin, northern Iran. The basin sediments date back to the Mio- and Pliocene and therefore represent the starting point of alluvial fan aggradation. Today, the still active alluvial fans prograde from the Albors Mountain ranges and sit on the older sediment bodies. In this study, our focus is on the late Pleistocene to Holocene alluvial fan sedimentation history. The upper stratigraphy of the alluvial fans and intercalated lake deposits is characterized by six individual layers of gravels and fines, representing six different stratigraphic units. These units are described and classified by detailed geomorphological and stratigraphic mapping. To establish an alluvial fan chronology, six profiles were sampled for OSL dating. As expected, due to the high-energy transport system of alluvial fan aggradation in semi-desert environments, OSL dating of these sediments is challenging due to the problem of insufficient bleaching. Consequently, most of the samples are interpreted as maximum ages. However, the measurements show a consistent internal age structure and the overall OSL-based chronology is in agreement with the age model derived from our geomorphological analysis. As a first interpretation, based on surveyed geomorphological features and chronological analysis, we could identify seven morphodynamic phases, leading to a genetic model of alluvial fan aggradation. The oldest Pleistocene age estimate is derived from a former lake terrace. The following ages represent ongoing lake sediment deposition and the development of a proximal and mid-fan gravel cover. After the youngest lake deposits were accumulated within the Holocene, the lake starts to retreat and small alluvial fans are filling up the former lake bottom. This last sedimentation phase can be divided in at least two sub-phases, probably coupled to a lateral shifting of the active depositional lobe and to the

  16. Energy dependence measurement of small-type optically stimulated luminescence (OSL) dosimeter by means of characteristic X-rays induced with general diagnostic X-ray equipment.

    Science.gov (United States)

    Takegami, Kazuki; Hayashi, Hiroaki; Okino, Hiroki; Kimoto, Natsumi; Maehata, Itsumi; Kanazawa, Yuki; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

    2016-01-01

    For X-ray inspections by way of general X-ray equipment, it is important to measure an entrance-skin dose. Recently, a small optically stimulated luminescence (OSL) dosimeter was made commercially available by Landauer, Inc. The dosimeter does not interfere with the medical images; therefore, it is expected to be a convenient detector for measuring personal exposure doses. In an actual clinical situation, it is assumed that X-rays of different energies will be detected by a dosimeter. For evaluation of the exposure dose measured by a dosimeter, it is necessary to know the energy dependence of the dosimeter. Our aim in this study was to measure the energy dependence of the OSL dosimeter experimentally in the diagnostic X-ray region. Metal samples weighing several grams were irradiated and, in this way, characteristic X-rays having energies ranging from 8 to 85 keV were generated. Using these mono-energetic X-rays, the dosimeter was irradiated. Simultaneously, the fluence of the X-rays was determined with a CdTe detector. The energy-dependent efficiency of the dosimeter was derived from the measured value of the dosimeter and the fluence. Moreover, the energy-dependent efficiency was calculated by Monte-Carlo simulation. The efficiency obtained in the experiment was in good agreement with that of the simulation. In conclusion, our proposed method, in which characteristic X-rays are used, is valuable for measurement of the energy dependence of a small OSL dosimeter in the diagnostic X-ray region.

  17. Estimation of identification limit for a small-type OSL dosimeter on the medical images by measurement of X-ray spectra

    OpenAIRE

    Takegami, Kazuki ; Hayashi, Hiroaki; Okino, Hiroki; Kimoto, Natsumi ; Maehata, Itsumi ; Kanazawa, Yuki ; Okazaki, Tohru ; Hashizume, Takuya ; Kobayashi, Ikuo 

    2016-01-01

    Our aim in this study is to derive an identification limit on a dosimeter for not disturbing a medical image when patients wear a small-type optically stimulated luminescence (OSL) dosimeter on their bodies during X-ray diagnostic imaging. For evaluation of the detection limit based on an analysis of X-ray spectra, we propose a new quantitative identification method. We performed experiments for which we used diagnostic X-ray equipment, a soft-tissue-equivalent phantom (1–20 cm), and a CdTe X...

  18. Assessing sedimentation rates at Usumacinta and Grijalva river basin (Southern Mexico) using OSL and suspended sediment load analysis: A study from the Maya Classic Period

    Science.gov (United States)

    Munoz-Salinas, E.; Castillo, M.; Sanderson, D.; Kinnaird, T.; Cruz-Zaragoza, E.

    2013-12-01

    Studying sedimentation rates on floodplains is key to understanding environmental changes occurred through time in river basins. The Usumacinta and Grijalva rivers flow most of their travel through the southern part of Mexico, forming a large river basin, crossing the states of Chiapas and Tabasco. The Usumacinta-Grijalva River Basin is within the 10 major rivers of North America, having a basin area of ~112 550 km2. We use the OSL technique for dating two sediment profiles and for obtaining luminescence signals in several sediment profiles located in the streambanks of the main trunk of the Usumacinta and Grijalva rivers. We also use mean annual values of suspended sediment load spanning ~50 years to calculate the sedimentation rates. Our OSL dating results start from the 4th Century, when the Maya Civilization was at its peak during the Classic Period. Sedimentation rates show a notable increase at the end of the 19th Century. The increase of the sedimentation rates seems to be related to changes in land uses in the Sierra Madre de Chiapas and Altos de Chiapas, based on deforestation and land clearing for developing new agrarian and pastoral activities. We conclude that the major environmental change in the basin of the Usumacinta and Grijalva Rivers since the Maya Classic Period was generated since the last Century as a result of an intense anthropogenic disturbance of mountain rain forest in Chiapas.

  19. Comparison of single-grain and small-aliquot OSL dose estimates in < 3000 years old river sediments from South India

    DEFF Research Database (Denmark)

    Thomas, P.J.; Jain, M.; Juyal, N.

    2005-01-01

    We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples, there wa......We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples......, there was an underestimation in the single-aliquot dose estimates as compared to those from the single grain-the difference between average dose estimates determined by the two methods ranged from similar to 1% to 31%. Such a dose underestimation was not detectable in poorly bleached samples. Various possible reasons...... perhaps be one of the reasons; this may occur because the stimulation wavelength affects the proportion of the medium and slow components in the initial signal. (c) 2004 Elsevier Ltd. All rights reserved....

  20. Synthesis and TL/OSL properties of a novel high-sensitive blue-emitting LiSrPO{sub 4}:Eu{sup 2+} phosphor for radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Palan, C.B.; Koparkar, K.A.; Omanwar, S.K. [Sant Gadge Baba Amravati University, Department of Physics, Amravati (India); Bajaj, N.S. [Toshniwal Arts, Commerce and Science College, Sengoan, Hingoli District, MH (India); Soni, A. [Bhabha Atomic Research Centre, Radiological Physics and Advisory Division, Mumbai (India)

    2016-07-15

    In this study, a series of Eu{sup 2+}-doped LiSrPO{sub 4} phosphors were synthesized via solid-state method. The structural and morphological characterizations were done through X-ray diffraction and scanning electronic microscope. Additionally, the photoluminescence (PL), thermoluminescence (TL) and optically stimulated luminescence (OSL) behaviours of LiSrPO{sub 4}:Eu{sup 2+} phosphors were studied. The LiSrPO{sub 4}:Eu{sup 2+} phosphor shows OSL sensitivity about 8 times than that of α-Al{sub 2}O{sub 3}:C phosphor and 6 times than that of LiMgPO{sub 4}:Tb{sup 3+}, B phosphor. Moreover, TL sensitivity was about 15 times more as compared to α-Al{sub 2}O{sub 3}:C phosphor. The kinetic parameters of TL curve were calculated using peak shape method. In TL/OSL mode, dose-response was almost linear nature, in the range of measurement. The minimum detectable dose was found to be 25.18 μGy with 3σ of background. Also, reusability was also studies, which shows the phosphor can be reusable for 10 cycles with 0.1 % change in OSL output. (orig.)

  1. Characterization of silicates and calcium carbonates applied to high-dose dosimetry; Caracterizacao de silicatos e carbonatos de calcio aplicados a dosimetria de doses altas

    Energy Technology Data Exchange (ETDEWEB)

    Vila, Gustavo Barreto

    2012-07-01

    The predominant isomorphous form in the biominerals studied in this work (oyster shell, coral, mother of pearl and shell) was aragonite. The appearance of the calcite phase occurred at 500 deg C at a heating rate of 10 deg {sup C}/s for all samples except for the coral sample, which was 400 deg C, independent of the heating rate. The most abundant element in the biominerals samples was Ca in the CaO form, and in the silicates (tremolite, diopside and rhodonite) Si in the SiO form. The most common trace element observed in the biominerals samples was Fe. The analyses of electron paramagnetic resonance showed lines of Mn{sup 2+} in the coral and mother-of-pearl samples before irradiation. In the case of the irradiated samples, the defects found were CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, CO{sub 3}{sup -} and SO{sub 2}{sup -}, in the g range between 2.0010 and 2.0062. In the analyses by optical absorption of biominerals, transitions due to the presence of Mn in the samples were found. A thermoluminescent (TL) peak at approximately 140 deg C was found for the biominerals and at 180 deg C for silicates, which intensity depends directly on the dose. For samples exposed to different types of radiation, the TL peak occurred at lower temperatures. From the dose-response curves obtained for these materials, it was possible to determine a linear range for which their application in high dose dosimetry becomes possible. Taking into account the radiation type, among biominerals and silicates, the lowest detectable dose (40mGy) to gamma radiation was achieved for oyster shell samples using the measuring technique of optically stimulated luminescence (OSL). Using beta radiation, for diopside and tremolite samples the lowest detectable dose of 60mGy was obtained. For all samples, using the TL, OSL and thermally stimulated exoelectron emission (TSEE) techniques in alpha, beta and gamma radiation beans a good response reproducibility was obtained. Therefore, the samples characterized

  2. New age estimations for the western outer city wall of ancient Tayma (NW Saudi Arabia) based on OSL and radiocarbon data and geomorphologic evidence

    Science.gov (United States)

    Engel, M.; Klasen, N.; Brückner, H.; Eichmann, R.; Hausleiter, A.; Al-Najem, M. H.; Al-Said, S. F.; Schneider, P. I.

    2009-04-01

    Since 2004 tremendous progress has been achieved in deciphering the cultural genesis of the Tayma oasis (NW Saudi Arabia), due to the joint investigations of the German Archaeological Institute Berlin (DAI), the General Commission for Tourism and Antiquities, Kingdom of Saudi Arabia, and the Department of Archaeology and Epigraphy, King Saud University Riyadh. Nevertheless, archaeological research is still suffering from a lacking locally-based absolute chronology of buildings. The pattern of ancient constructions at Tayma is dominated by a prominent city wall system surrounding the ancient town center (Qraya) and stretching 15 km around the oasis. Its internal structure indicates several building periods, i.e. phases of wall modification or extension of the entire system. So far, according to silex and carnelian fragments included in the mud bricks and a previous 14C age of charcoal remains from the central excavation district (wall section at Area A), an initial construction date of the wall between the late 3rd and the early 2nd millennium BC seemed likely. At the excavated western outer city wall a new systematic dating approach - combining the optically stimulated luminescence (OSL) and 14C methods - has been applied to generate a reliable age for the oldest branch of the wall system which nowadays is covered by aeolian sand. The dune deposit is genetically related to the existence of the wall and, therefore, dating its accumulation provides termini ante quem for the construction of the wall. Five OSL dates were generated from the dune deposit providing ages between 4,900 and 3,500 yrs. Two radiocarbon ages support the dating sequence and also contribute to its consistency. By combining the results with geomorphologic evidence we draw the following conclusions: Initial settlement activities at Qraya were accompanied by a regulation of wadi dynamics and the construction of the outer city wall, indicated by the abrupt boundary between the pre-settlement alluvial

  3. Quaternary alluvial fans of Ciudad Juárez, Chihuahua, northern México: OSL ages and implications for climatic history of the region

    Science.gov (United States)

    Zúñiga de León, David; Kershaw, Stephen; Mahan, Shannon

    2016-01-01

    Alluvial fans formed from sediments derived from erosion of the Juárez Mountains in northernmost México have a significant flood impact on the Ciudad Juárez, which is built on the fan system. The northern part of Ciudad Juárez is the most active; further south, older parts of the fan, upon which the rest of the city is built, were largely eroded by natural processes prior to human habitation and subsequently modified only recently by human construction. Three aeolian sand samples, collected from the uppermost (youngest) parts of the fan system in the city area, in places where human intervention has not disturbed the sediment, and constrain the latest dates of fan building. Depositional ages of the Quaternary alluvial fans were measured using Optically Stimulated Luminescence (OSL) on aeolian sands that have inter-fingered with alluvial fan material. These dates are: a) sample P1, 31 ka; b) sample P2, 41 ka; c) sample P3, 74 ka, between Oxygen Isotope Stages (OIS) 3 to 5. They demonstrate that fan development, in the area now occupied by the city, terminated in the Late Pleistocene, immediately after what we interpret to have been an extended period of erosion without further deposition, lasting from the Late Pleistocene to Holocene. The three dates broadly correspond to global glacial periods, implying that the cool, dry periods may reflect periods of aeolian transport in northern México in between phases that were wetter to form the alluvial fans. Alluvial fan margins inter-finger with fluvial terrace sediments derived from the Río Bravo, indicating an additional component of fan dissection by Río Bravo lateral erosion, presumed to be active during earlier times than our OSL ages, but these are not yet dated. Further dating is required to ascertain the controls on the fan and fluvial system.

  4. An integrated OSL chronology, sedimentology and geochemical approach to loess deposits from Tuoji Island, Shandong Province: Implications for the late quaternary paleoenvironment in East China

    Science.gov (United States)

    Xu, Shujian; Kong, Fanbiao; Jia, Guangju; Miao, Xiaodong; Ding, Xinchao

    2018-04-01

    The Tuoji II (TJII) section on the Miaodao Islands in the Bohai Sea is a representative aeolian section off China's east coast. This study applied optically stimulated luminescence (OSL) dating, conducted grain size analysis, and examined major and trace element compositions, to investigate the loess-paleosol sequences. The OSL ages at depths of 0.6, 1.8, 2.8, 3.8, and 4.8 m were determined as 14.4 ± 0.4, 16.7 ± 1.3, 20.8 ± 1.0, 40.9 ± 1.5, and 47.9 ± 3.7 ka, respectively. It was projected that the loess started to accumulate at ca. 62.6 ka, according to presumed depositional rates. In this study, typical aeolian deposits elsewhere including the Luochuan (LC), Xiashu (XS), Wushan (WS), and Xifeng (XF) sections were compared with TJII section here. The results showed similarity in the geochemical characteristics of the deposits from the different areas of China and normalized upper continental crust, indicating aeolian origin of this island loess. In comparison with the LC, XS, WS, and XF samples, the aeolian deposits of the TJII section have higher concentrations of TiO2 and Zr and lower concentrations of Al2O3, Rb, and Ni, and they have higher SiO2/Al2O3 and TiO2/Al2O3 ratios and lower Al2O3/Na2O and Ba/Sr ratios. These features indicate the dust materials of the TJII section were derived from local sources of well-mixed sedimentary protoliths. Our results support the suggestion that paleoclimatic change and the evolution of aeolian sediments were controlled primarily by variation of the East Asian summer monsoon and sea level change.

  5. Persistent luminescence, TL and OSL characterization of beta irradiated SrAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} combustion synthesized phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Zúñiga-Rivera, N.J. [Departamento de Física, Posgrado en Nanotecnología, Universidad de Sonora, Hermosillo, Sonora 83000 (Mexico); García, R.; Rodríguez-Mijangos, R.; Chernov, V.; Meléndrez, R.; Pedroza-Montero, M. [Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora 83000 (Mexico); Barboza-Flores, M., E-mail: mbarboza@cifus.uson.mx [Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora 83000 (Mexico)

    2014-05-01

    The persistent luminescence (PLUM), thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of strontium aluminates co-doped with Eu{sup +2} and Dy{sup +3} exposed to beta radiation is reported. The phosphor was synthesized by the combustion synthesis method employing a highly exothermic redox reaction between the metal nitrates [Al(NO{sub 3}){sub 3}, Sr(NO{sub 3}){sub 2}, Eu(NO{sub 3}){sub 3} and Dy(NO{sub 3}){sub 3}] and organic fuel carbohydrazide (CH{sub 6}N{sub 4}O). The long decay PLUM emission, TL and OSL were measured as a function of beta radiation dose. A wide emission band centered at 510 nm (green) related to Eu{sup 2+} ions and lattice defects were observed for the synthesized samples. The presence of a variety of defects and aggregates were responsible for the observed broad 100 °C peaked TL glow curve of the irradiated sample which is composed of several overlapped TL peaks. The existence of multiple trapping levels, with different trapping/detrapping probabilities, is behind the particular features for the PLUM, TL and OSL emissions. We conclude that in the SrAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} phosphors, the low temperature TL peaked around 30–75 °C is responsible for the PLUM emission and those around 100 °C were related to very stable trapping states which provide suitable radiation storage properties to be used as a PLUM/TL/OSL radiation phosphor.

  6. Intracavitary in vivo dosimetry based on multichannel fiber-coupled optically stimulated luminescence (OSL) of Al2O3:C for Curietherapy

    International Nuclear Information System (INIS)

    Spasic, Estelle

    2012-01-01

    The brachytherapy is an old technique using sealed radioactive sources of low or average energy. This technique is still therapeutically and economically relevant today and always evolving (e.g. High Dose Rate (HDR) brachytherapy). This treatment enables to deliver a high dose of irradiation in a limited tumoral volume and enables to minimize the risk of radiation-induced cancer as preserving the Organs at Risks (OAR). However, this technique generates high dose gradients, which makes in vivo dosimetry difficult to implement. Hence, the deviations observed between doses delivered and prescribed are often up to the maximal deviation tolerated by the nuclear safety regulations (± 5%) in conformational radiotherapy. Those regulations have been made mandatory in France since 2011. This thesis has been done within the framework of the ANR-TECSAN INTRADOSE project and is based on the past technological benefits demonstrated during the MAESTRO European project and the ANR-TECSAN CODOFER project, in particular a RL/OSL multichannel instrumentation (Radioluminescence - Optically Stimulated Luminescence) made and validated in preclinical evaluation during the MAESTRO project. The purpose of the INTRADOSE project is to demonstrate the feasibility of the intracavitary In Vivo Dosimetry (IVD) by dosimetric catheter using optical fibers and alumina crystals Al 2 O 3 :C with the aim of improving the safety of patients treated by HDR brachytherapy. This new probe enables to measure a dose distribution (several points) close to the OAR, it offers a little diameter (≤ 3 mm) designed for an intracavitary use (e.g. to insert in the urethra), it is transparent, radiation stable and reusable after dose reading and sterilization. During this study, we have first developed this new dosimetric sensor based on the OSL using the properties of the alumina crystal. Several tests have been done in order to evaluate the feasibility and the compatibility with a medical application. Then

  7. Rapid and cyclic dust accumulation during MIS 2 in Central Asia inferred from loess OSL dating and grain-size analysis.

    Science.gov (United States)

    Li, Yun; Song, Yougui; Lai, Zhongping; Han, Li; An, Zhisheng

    2016-09-02

    Due to lack of reliable proxies from the Westerlies-dominant region, the strength change of Northern Hemisphere Westerlies remains poorly understood. The aim of this study is to provide a reliable paleoclimatic proxy about the Northern Hemisphere Westerlies change. Here we report a 30.7 m thick loess section from the Ili basin directly controlled by the Westerlies. Based on optically stimulated luminescence (OSL) and high resolution grain-size records, we reconstruct the change history of the Westerlies strength during the last glacial period (mainly Marine Isotope Stages 2, MIS2), being similar with the Westerlies index recorded in the Qinghai Lake sediments. Within error limits, all ages are in stratigraphic order. We further compare the climatic records among the Ili loess, Qinghai Lake and the NGRIP, their similarity shows a good climatic coupling relationship among the Central Asia, East Asia and the North Atlantic, and the Westerlies plays a critical influence in transporting the North Atlantic signal to Central and East Asia.

  8. Comparison of single-grain and small-aliquot OSL dose estimates in <3000 years old river sediments from South India

    International Nuclear Information System (INIS)

    Thomas, P.J.; Jain, M.; Juyal, N.; Singhvi, A.K.

    2005-01-01

    We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples, there was an underestimation in the single-aliquot dose estimates as compared to those from the single grain-the difference between average dose estimates determined by the two methods ranged from ∼1% to 31%. Such a dose underestimation was not detectable in poorly bleached samples. Various possible reasons for the discrepancy between single-grain and small-aliquot dose estimates are discussed. Although there is no satisfactory explanation for this discrepancy, we speculate that the difference in the stimulation wavelengths, 470+/-30nm in the case of single-aliquot and 532nm in the case of single grains, could perhaps be one of the reasons; this may occur because the stimulation wavelength affects the proportion of the medium and slow components in the initial signal

  9. Neutron dosimetry; Dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fratin, Luciano

    1993-12-31

    A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is sufficiently sensitive to thermal and intermediate neutrons but fast neutron monitoring ar radiological protection level would require an integration period of over a month. The proposed dosimetric procedure is based on the conjugated use of the developed personal dosemeter and the Bonner multisphere spectrometer. (author) 58 refs., 31 figs., 12 tabs.

  10. Neutron dosimetry; Dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fratin, Luciano

    1994-12-31

    A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is sufficiently sensitive to thermal and intermediate neutrons but fast neutron monitoring ar radiological protection level would require an integration period of over a month. The proposed dosimetric procedure is based on the conjugated use of the developed personal dosemeter and the Bonner multisphere spectrometer. (author) 58 refs., 31 figs., 12 tabs.

  11. Characterization and implementation of OSL dosimeters for use in evaluating the efficacy of organ-based tube current modulation for CT scans of the face and orbits

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, R. M.; Silosky, M., E-mail: michael.silosky@ucdenver.edu [Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)

    2015-04-15

    Purpose: The purpose of this work was to characterize commercially available optically stimulated luminescent (OSL) dosimeters for general clinical applications and apply the results to the development of a method to evaluate the efficacy of a vendor-specific organ-based tube current modulation application for both phantom and clinical computed tomography (CT) scans of the face and orbits. Methods: This study consisted of three components: (1) thorough characterization of the dosimeters for CT scans in phantom, including evaluations of depletion, fading, angular dependence, and conversion from counts to absorbed dose; (2) evaluation of the efficacy of using plastic glasses to position the dosimeters over the eyes in both phantom and clinical studies; and (3) preliminary dosimetry measurements made using organ-based tube current modulation in computed tomography dose index (CTDI) and anthropomorphic phantom studies. Results: (1) Depletion effects were found to have a linear relationship with the output of the OSL dosimeters (R{sup 2} = 0.96). Fading was found to affect dosimeter readings during the first two hours following exposure but had no effect during the remaining 60-h period observed. No significant angular dependence was observed for the exposure conditions used in this study (with p-values ranging from 0.9 to 0.26 for all t-tests). Dosimeter counts varied linearly with absorbed dose when measured in the center and 12 o’clock positions of the CTDI phantoms. These linear models of counts versus absorbed dose had overlapping 95% confidence intervals for the intercepts but not for the slopes. (2) When dosimeters were positioned using safety glasses, there was no adverse effect on image quality, and there was no statistically significant difference between this placement and placement of the dosimeters directly on the eyes of the phantom (p = 0.24). (3) When using organ-based tube current modulation, the dose to the lens of the eye was reduced between 19% and

  12. Characterization and implementation of OSL dosimeters for use in evaluating the efficacy of organ-based tube current modulation for CT scans of the face and orbits

    International Nuclear Information System (INIS)

    Marsh, R. M.; Silosky, M.

    2015-01-01

    Purpose: The purpose of this work was to characterize commercially available optically stimulated luminescent (OSL) dosimeters for general clinical applications and apply the results to the development of a method to evaluate the efficacy of a vendor-specific organ-based tube current modulation application for both phantom and clinical computed tomography (CT) scans of the face and orbits. Methods: This study consisted of three components: (1) thorough characterization of the dosimeters for CT scans in phantom, including evaluations of depletion, fading, angular dependence, and conversion from counts to absorbed dose; (2) evaluation of the efficacy of using plastic glasses to position the dosimeters over the eyes in both phantom and clinical studies; and (3) preliminary dosimetry measurements made using organ-based tube current modulation in computed tomography dose index (CTDI) and anthropomorphic phantom studies. Results: (1) Depletion effects were found to have a linear relationship with the output of the OSL dosimeters (R 2 = 0.96). Fading was found to affect dosimeter readings during the first two hours following exposure but had no effect during the remaining 60-h period observed. No significant angular dependence was observed for the exposure conditions used in this study (with p-values ranging from 0.9 to 0.26 for all t-tests). Dosimeter counts varied linearly with absorbed dose when measured in the center and 12 o’clock positions of the CTDI phantoms. These linear models of counts versus absorbed dose had overlapping 95% confidence intervals for the intercepts but not for the slopes. (2) When dosimeters were positioned using safety glasses, there was no adverse effect on image quality, and there was no statistically significant difference between this placement and placement of the dosimeters directly on the eyes of the phantom (p = 0.24). (3) When using organ-based tube current modulation, the dose to the lens of the eye was reduced between 19% and 43

  13. Thermally assisted OSL application for equivalent dose estimation; comparison of multiple equivalent dose values as well as saturation levels determined by luminescence and ESR techniques for a sedimentary sample collected from a fault gouge

    Energy Technology Data Exchange (ETDEWEB)

    Şahiner, Eren, E-mail: sahiner@ankara.edu.tr; Meriç, Niyazi, E-mail: meric@ankara.edu.tr; Polymeris, George S., E-mail: gspolymeris@ankara.edu.tr

    2017-02-01

    Highlights: • Multiple equivalent dose estimations were carried out. • Additive ESR and regenerative luminescence were applied. • Preliminary SAR results employing TA-OSL signal were discussed. • Saturation levels of ESR and luminescence were investigated. • IRSL{sub 175} and SAR TA-OSL stand as very promising for large doses. - Abstract: Equivalent dose estimation (D{sub e}) constitutes the most important part of either trap-charge dating techniques or dosimetry applications. In the present work, multiple, independent equivalent dose estimation approaches were adopted, using both luminescence and ESR techniques; two different minerals were studied, namely quartz as well as feldspathic polymineral samples. The work is divided into three independent parts, depending on the type of signal employed. Firstly, different D{sub e} estimation approaches were carried out on both polymineral and contaminated quartz, using single aliquot regenerative dose protocols employing conventional OSL and IRSL signals, acquired at different temperatures. Secondly, ESR equivalent dose estimations using the additive dose procedure both at room temperature and at 90 K were discussed. Lastly, for the first time in the literature, a single aliquot regenerative protocol employing a thermally assisted OSL signal originating from Very Deep Traps was applied for natural minerals. Rejection criteria such as recycling and recovery ratios are also presented. The SAR protocol, whenever applied, provided with compatible D{sub e} estimations with great accuracy, independent on either the type of mineral or the stimulation temperature. Low temperature ESR signals resulting from Al and Ti centers indicate very large D{sub e} values due to bleaching in-ability, associated with large uncertainty values. Additionally, dose saturation of different approaches was investigated. For the signal arising from Very Deep Traps in quartz saturation is extended almost by one order of magnitude. It is

  14. Temporal limits to the archaeological record in arid western NSW, Australia : lessons from OSL and radiocarbon dating of hearths and sediments

    International Nuclear Information System (INIS)

    Fanning, P.; Holdaway, S.

    2001-01-01

    The Western NSW Archaeology Program (WNSWAP) has been investigating surface scatters of Aboriginal stone artefacts and associated heat-retainer hearths in arid northwestern NSW, Australia, since 1995. The research combines new methods for documenting and analysing stone artefact scatters with an understanding of geomorphic landscape dynamics to seek insights into spatial and temporal patterns of Aboriginal occupation of the arid margin of Australia during the Late Holocene. The temporal dimension is dealt with in two ways: by radiocarbon determinations on charcoal from the remains of heat-retainer hearths associated with the artefact scatters, and by using optically simulated luminescence (OSL) and radiocarbon determinations from valley fill sediments to develop a chronology of landscape evolution of the valleys in which the artefacts and hearths are found. The heat-retainer hearths produced a record of just less than 2000 years of activity within the valley of Stud Creek, a 30 square km catchment in Sturt National Park. However, the record is discontinuous, with a gap in heat-retainer hearth construction of 200-400 years occurring between about 800 and 1100 y BP. Examination of patterns of erosion and deposition at the places where the hearths were found, and Bayesian statistical analysis of the radiocarbon determinations, demonstrates that this gap is real and not an artefact of the survey protocol. A discontinuous record is also evident when the sediments that comprise the valley fill upon which the hearths and stone artefact scatters are currently lying are examined. Five major sedimentary units can be identified, providing a record of depositional episodes ranging from modern or post-European back to the Late Pleistocene (about 70,000 years). But, in contrast to the record from the remains of the heat-retainer hearths, erosion is the major determinant of the temporal pattern of landscape change that can be reconstructed from this record. Gaps of up to 10

  15. SU-F-P-50: Performance Evaluation of Optically Stimulated Luminescence (OSL) NanoDots in Therapy and Imaging In-Vivo Dose Measurement During Patient Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S; Sarkar, B; Kaur, H; Rathinamuthu, S; Giri, U; Jassal, K; Ganesh, T; Munshi, A; Mohanti, B; Krishnankutty, S; Sathiya, J [Fortis Memorial Research Institute, Gurgaon, Haryana (India)

    2016-06-15

    Purpose: This study was designed to evaluate the performance of optically stimulated Luminescence (OSL) nanoDots as in-vivo dosimeter. For the measurements of surface doses as well as scattered plus leakage doses, nanoDots were used during the setup verification as well as during the treatment delivery. Methods: For a total seven patients undergoing radiotherapy by volumetric modulated arc therapy, surface doses from image guidance and scattered plus leakage doses from treatment delivery were measured. Two sets of calibration curves were generated – one for therapy and another for imaging. Two different nanoDots were used for imaging and therapy doses. Imaging nanoDots were placed at the isocenter only at the time of CBCT and therapy nanoDots were placed at 25 cm away from the isocenter (either in cranial or in caudal direction) only at the time of treatment delivery. During the entire course, nanoDots were placed at the same measurement points. NanoDots were read after 15 minutes of their exposure. For the next fraction, nanoDots were corrected for the residual doses from the previous fractions. Results: Measured surface doses during imaging were 0.14±0.32 cGy, 0.11±0.04 cGy, 0.12±0.53 cGy, 0.04±0.02 cGy, 0.13±0.23 cGy, 0.11±0.43 cGy, 0.10±0.04 cGy with overall mean dose of 0.08±0.1 cGy. Measured doses during treatment delivery, indicative of scattered and leakage dose, were 0.84±0.43 cGy, 1.3±0.4 cGy, 1.4±0.4 cGy, 0.18±0.48 cGy, 0.78±0.29 cGy, 0.27±0.08 cGy, 0.78±0.07 cGy with overall mean dose of 0.61±1.3 cGy. Conclusion: This dosimeter can be used as supplementary unit to verify the doses. No change in the prescription is recommended based on nanoDots measurement. This study is on-going therefore we are presenting only mere number of patients. A large volume data will be presented after completion of the study with proper statistical analysis.

  16. Production and characterization of compounds based on MgB{sub 4}O{sub 7} for application in dosimetry; Producao e caracterizacao de compostos a base de MgB{sub 4}O{sub 7} para aplicacao em dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Luiza Freire de

    2016-07-01

    Many materials with luminescent properties are used for ionizing radiation dosimetry through the thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques. Detectors based on lithium fluoride (LiF), calcium sulphate (CaSO{sub 4}) and aluminum oxide (Al{sub 2}O{sub 3}), doped or codoped with various elements, are the TL or OSL commercial dosimeters most widely used currently. However, several researches are focused to the development of new TL /OSL materials in intention to enhance the dosimetric properties, in view that no TL/OSL dosimeter has all the ideal characteristics for monitoring the radiation. In this context, magnesium tetraborate (MgB{sub 4}O{sub 7}), which has been presented in the literature as a material for dosimetry TL, was investigated in this work. As there are no reports on the structural characterization of this material or regarding to its applicability on OSL dosimetry, the proposal of the present work was to develop compounds based on MgB{sub 4}O{sub 7}, with different doping, by solid state synthesis. It was made the structural, optical, TL and OSL characterization of the compound to verify it feasibility for application on radiation dosimetry. Initially, it was determined the calcination temperature and time for MgB{sub 4}O{sub 7} formation, with the use of thermal analyses and x ray diffraction. The ideal calcination was found at 900 °C for 7 hours. It were produced , in powder form, the compounds: MgB{sub 4}O{sub 7}, MgB{sub 4}O{sub 7}:Dy, MgB{sub 4}O{sub 7}:Dy,Li, MgB{sub 4}O{sub 7}:Ce, MgB{sub 4}O{sub 7}:Ce,Li, MgB{sub 4}O{sub 7}:Nd and MgB{sub 4}O{sub 7}:Nd,Li. For TL and OSL analyses it were produced pellets sintering at 950 °C for 2 hours. The radioluminescence (RL) analyses of MgB{sub 4}O{sub 7}:Dy and MgB{sub 4}O{sub 7}:Dy,Li shows wavelength emissions at 490, 590, 670 and 760 nm. For MgB{sub 4}O{sub 7}:Ce and MgB{sub 4}O{sub 7}:Ce,Li RL was observed wide emission band in the ultraviolet region. For the Mg

  17. Tl and OSL dose response of LiF:Mg, Ti and Al{sub 2}O{sub 3}:C dosimeters using a PMMA phantom for IMRT technique quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, L. C.; Veneziani, G. R.; Campos, L. L. [Instituto de Pesquisas Energeticas e Nucleares, Gerencia de Metrologia das Radiacoes / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Sakuraba, R. K.; Cruz, J. C., E-mail: lmatsushima@usp.br [Sociedade Beneficente Israelita Brasileira - Hospital Albert Einstein, Av. Albert Einstein 627/701, Morumbi, 05652-000 Sao Paulo (Brazil)

    2014-08-15

    The principle of IMRT is to treat a patient from a number of different directions (or continuous arcs) with beams of nonuniform fluences, which have been optimized to deliver a high dose to the target volume and an acceptably low dose to the surrounding normal structures (Khan, 2010). This study intends to provide information to the physicist regarding the application of different dosimeters type, phantoms and analysis technique for Intensity Modulated Radiation Therapy (IMRT) dose distributions evaluation. The measures were performed using dosimeters of LiF:Mg,Ti and Al{sub 2}O{sub 3}:C evaluated by techniques of thermoluminescent (Tl) and Optically Stimulated Luminescence (OSL). A polymethylmethacrylate (PMMA) phantom with five cavities, two principal target volumes considered like tumours to be treated and other three cavities to measure the scattered radiation dose was developed to carried out the measures. (Author)

  18. Application of the thermoluminescent (TL) and optically stimulated luminescence (OSL) dosimetry techniques to determinate the isodose curves in a cancer treatment planning simulation using Volumetric Modulated Arc Therapy - VMAT

    International Nuclear Information System (INIS)

    Bravim, Amanda

    2015-01-01

    The Volumetric Modulated Arc Therapy (VMAT) is an advance technique of Intensity Modulated Radiation Therapy (IMRT). This progress is due to the continuous gantry rotation with the radiation beam modulation providing lower time of the patient treatment. This research aimed the verification of the isodose curves in a simulation of a vertebra treatment with spinal cord protection using the thermoluminescent (TL) and optically stimulated luminescence (OSL) dosimetry techniques and the LiF:Mg,Ti (TLD-100), CaS0 4 :Dy and Al 2 0 3 :C dosimeters and LiF:Mg,Ti micro dosimeters (TLD-100). The dosimeters were characterized using PMMA plates of 30 x 30 x 30 cm 3 and different thickness. All irradiations were done using Truebeam STx linear accelerator of Hospital Israelita Albert Einstein, with 6 MV photons beam. After the dosimeter characterization, they were irradiated according the specific planning simulation and using a PMMA phantom developed to VMAT measurements. This irradiation aimed to verify the isodose curves of the treatment simulation using the two dosimetry techniques. All types of dosimeters showed satisfactory results to determine the dose distribution but analysing the complexity of the isodose curves and the proximity of them, the LiF:Mg,Ti micro dosimeter showed the most appropriate for use due to its small dimensions. Regarding the best technique, as both technique showed satisfactory results, the TL technique presents less complex to be used because the most of the radiotherapy departments already have a TL laboratory. The OSL technique requires more care and greater investment in the hospital. (author)

  19. Individual monitoring of external exposure in terms of personal dose equivalent, H{sub p}(d); Dosimetria personale esterna in termini di equivalente di dose personale, H{sub p}(d). Atti. Giornata di studio, Bologna, 28 febbraio 2001

    Energy Technology Data Exchange (ETDEWEB)

    Fantuzzi, E. [ENEA, Div. Protezione dell' Uomo e degli Ecosistemi, Centro Ricerche Ezio Clementel, Bologna (Italy)

    2001-07-01

    The institute for Radiation Protection of ENEA - Bologna has organised a one day-workshop on the subject: Individual monitoring of external exposure in terms of personal dose equivalent, H{sub p}(d). The aim of the workshop was the discussion of the new implications and modifications to be expected in the routine individual monitoring of external radiation, due to the issue of the Decree 241/00 (G.U. 31/8/2000) in charge since 01/01/2001. The decree set up in Italian law the standards contained in the European Directive EURATOM 96/29-Basic Standards for the Protection of Health of Workers and the General Public against Dangers arising from Ionizing Radiation. Among others, the definition of the operational quantities for external radiation for personal and environmental monitoring, H{sub p}(d) e H{sup *}(d) respectively as defined by ICRU (International Commission for Radiation Units and Measurements), requires to update the methods of measurements and calibration of the personal dosemeters and environmental monitors. This report collects the papers presented at the workshop dealing with the Personal Dose Equivalent, H{sub p}(d), the conversion coefficients, H{sub p}(d)/K{sub a} e H{sub p}(d)/{sub ,} obtained through Monte Carlo calculations published by ICRU and ICRP (International Commission for Radiation Protection), the new calibration procedures and the practical implication in the routine of individual monitoring in terms of H{sub p}(d). Eventually, in the last chapter, the answers to Frequently Asked Questions (FAQ) are briefly reported. [Italian] L'Istituto per la Radioprotezione dell'ENEA di Bologna ha organizzato una giornata di studio Dosimetria personale esterna in termini di equivalente di dose personale, H{sub p}(d). Lo scopo della giornata e' stato quello di discutere le novita' e le modifiche da apportare alle pratiche di monitoraggio dell'esposizione esterna alle radiazioni ionizzanti, a seguito dell'entrata in vigore

  20. Validation and dosimetric evaluation employing the techniques of TL and OSL of thermoluminescent materials for application in the dosimetry of clinical beams of electrons used in total irradiation of the skin - TSI

    International Nuclear Information System (INIS)

    Almeida, Shirlane Barbosa de

    2017-01-01

    In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance program that should be an integral part of the radiotherapy departments. TSI dosimetry is difficult because of the complexity of the treatment in assessing dose uniformity and measuring the dose absorbed at shallow depths throughout the skin surface extent, resulting in a wide variation in dose distribution. The TLDs have proven to be very useful for the distribution and verification of the dose prescribed for the patient as the dose may differ from place to place due to patient body geometry, overlapping of structures and asymmetries of the radiation field. The use of TLDs in vivo can identify variations in the prescribed dose because its measurement accuracy and great precision. Several types of dosimeters have been used in the radiotherapy sectors, the most commonly used are Lithium Fluride (TLD-100), where it obtains a long history in this type of application. New dosimetric materials have gained great importance in the dosimetry of clinical electron beams, such as Dysprosium-doped Calcium Sulphate (TL) and Carbon doped (OSL) based Aluminum Oxide, This work evaluates the performance of the respective thermoluminescent dosimeters and the optically stimulated luminescence in the dosimetry of clinical electron beams used in total irradiation of the skin. (author)

  1. The Why and How of Nuclear Accident Dosimetry; Dosimetrie en cas d'Accident Nucleaire: Raison d'Etre et Modalites; 041e 0411 041e 0421 041d 041e 0412 0414 ; Dosimetria en Casos de Accidente Nuclear: Justificacion y Modalidades

    Energy Technology Data Exchange (ETDEWEB)

    Vallario, E. J.; Wasson, H. R. [United States Atomic Energy Commission, Washington, DC (United States)

    1965-06-15

    des accidents nucleaires risquent de se produire. Lors de la mise au point d'un tel programme, il convient d'etudier certains parametres fondamentaux, a savoir: a) une methode permettant de trier les membres du personnel victimes d'un accident nucleaire; b) un systeme fixe (dispositif primaire) capable de determiner, avec un degre d'exactitude convenu la dose de premier choc a son emplacement meme; c) la necessite de disposer d''appareils secondaires'; d) la necessite de munir le personnel d'un dispositif donnant des indications sur le spectre et le flux afin de faciliter l'extrapolation de la dose en permettant de passer du dispositif fixe a l'emplacement de la personne exposee. La cellule de detection neutronique du systeme devrait renseigner sur le flux et le spectre, de maniere a obtenir des indications qualitatives appropriees dans l'evaluation de la dose. Les degres d'exactitude devront etre fixes d'apres l'etat actuel des connaissances. D'autre part, la cellule de detection gamma devrait permettre de mesurer ce rayonnement dans les limites des intensites d'interet biologique, soit entre 10 et 10{sup 3}r. Pour qu'un systeme de dosimetrie en cas d'accident soit efficace, le nombre d'appareils doit etre suffisant et leur emplacement bien choisi ; il faut aussi pouvoir les recuperer facilement. Si ces conditions sont remplies, on doit obtenir des donnees satisfaisantes sur toute l'etendue du spectre de fission. (author) [Spanish] La finilidad de un programa eficaz de dosimetria es la evaluacion de la dosis de neutrones y rayos gamma resultante de un accidente nuclear. A este respecto, el autor examina las limitaciones que presenta el dosimetro de pelicula, y trata ademas de la experiencia adquirida con ocasion de determinados accidentes nucleares, experiencia que ha demostrado la necesidad de establecer un programa eficaz de dosimetria en las instalaciones en que no se excluya la posibilidad de que se produzcan accidentes de esta clase. Para establecer un programa

  2. High-Dose Ionizing Radiation Photographic Dosimetry; Mesure, par des Methodes Photogra Phiques, de Doses Elevees de Rayonnements Ionisants; 0424 041e 0422 041e 0413 0420 0414 ; Dosimetria Fotografica de Dosis Elevadas de Radiaciones Ionizantes

    Energy Technology Data Exchange (ETDEWEB)

    Trousil, J.; Bucina, I. [Institute for Research Production and Application of Radioisotopes Prague, Czechoslovakia (Czech Republic)

    1965-06-15

    ionizantes comprendidas entre 10 mr y 1000 r (para rayos gamma y rayos X de elevada energia). Con arreglo a este metodo, se utilizan dos peliculas con emulsiones diferentes, montadas en el mismo estuche. El metodo se caracteriza esencialmente por el hecho de que permite evaluar dosis comprendidas entre los limites indicados, sin necesidad de saber si se produjo una exposicion a dosis mas elevadas, con un margen de error inferior a {+-}25 en todo el intervalo (limite de seguridad 95%); ademas permite determinar con una precision satisfactoria la energia de las radiaciones a que la pelicula estuvo expuesta. Se examinan los aparatos, peliculas y tratamiento quimicos necesarios para esas mediciones. Se explica el principio de construccion de un densitometro que permite medir el ennegrecimiento de la pelicula con una precision constante en el intervalo comprendido entre D = 0 y D = 6. De este modo es posible aprovechar toda la zona de ennegrecimiento de la pelicula correspondiente a dicho intervalo. Como no se utiliza iotomultiplicador, los riesgos de iluminacion excesiva se reducen al minimo, por lo que el aparato resulta apropiado para mediciones corrientes. Ademas se indican los parametros que han de satisfacer las peliculas dosimetricas para poder detectar dosis elevadas, y se comparan las caracteristicas de las peliculas dosimetricas FOMA y ORWO en lo que respecta a la medicion de dosis elevadas. Con un progreso en la dosimetria de dosis elevadas, cabe mencionar el metodo de revelado retardado que se describe con detalle, con arreglo al cual se anaden al revelador compuestos del tipo nitrobenzimidazol y benzotriazol, en concentracion adecuada. En el caso de emulsiones lentas con elevado contenido de plata, esta tecnica permite medir exposiciones de dosis gamma (rayos X de elevada energia) de hasta 10{sup 3}r, o aun mayores, si no es menester una evaluacion precisa en un intervalo de hasta 100 r. Se describe el efecto retardador de los productos quimicos anadidos al revelador

  3. The Importance of Dosimetry to the Medical Management of Persons Accidentally Exposed to High Levels of Radiation; Le Role de la Dosimetrie Dans les Soins Medicaux a Donner aux Personnes Accidentellement Exposees a de Fortes Doses de Rayonnement; 0417 041d 0410 0427 0414 ; Importancia de la Dosimetria para el Tratamiento Medico de las Personas Accidentalmente Expuestas a Dosis Elevadas de Radiaciones

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, G. A.; Lushbaugh, C. C. [Medical Division, Oak Ridge Institute of Nuclear Studies (United States); Auxier, J. A. [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1965-06-15

    Radiation accidents continue to occur sporadically and it appears that there is no hope of eliminating them entirely. The management of patients exposed to large doses of radiation is constantly improving because of increasing ability to prevent and treat infection and to control haemorrhage. The possible effectiveness of temporary bone marrow grafts offers promise of a further reduction in mortality. The use of this growing biological information is closely related to, and to a large extent dependent upon, improvements in physical dosimetry for radiation accidents. (author) [French] Des accidents provoques par les rayonnements continuent a se produire de temps a autre et il ne semble guere que l'on puisse esperer les eliminer entierement. Toutefois, le traitement des sujets exposes a de fortes doses de rayonnement ne cesse de s'ameliorer; on parvient, en effet, dans une mesure croissante a empecher et a traiter l*infection ainsi qu'a arreter l'hemorragie. Comme la greffe temporaire de la moelle des os semble devoir donner des resultats, on peut s*attendre a une nouvelle reduction du taux de mortalite. L'application de ces connaissances biologiques sans cesse accrues est fonction, dans une large mesure, des ameliorations apportees a la dosimetrie physique des accidents nucleaires. (author) [Spanish] De vez en cuando se siguen produciendo accidentes de irradiacion y las perspectivas de evitarlos por completo parecen ser bastante remotas. El tratamiento de las victimas expuestas a dosis elevadas de radiaciones mejora constantemente debido a la creciente posibilidad de prevenir y tratar las infecciones, y de controlar las hemorragias. Tambien es posible que la eficacia de ios injertos temporales de medula osea se traduzca en una disminucion de la mortalidad. El aprovechamiento de estos conocimientos biologicos cada vez mas amplios guarda una estrecha relacion con los perfeccionamientos en materia de dosimetria fisica en caso de accidentes de irradiacion. (author

  4. OSL properties of anthropological bone and tooth

    International Nuclear Information System (INIS)

    Meric, Niyazi; Kosal, Mehmet; Altay Atlihan, M.; Rabia Yuece, Ulkue

    2008-01-01

    The aim of present work was to investigate whether anthropological bone and teeth can be used in dosimetric and dating studies. The radiation dose responses of anthropological human bone and pig teeth were obtained and studied using infrared stimulated luminescence (IRSL). The radiation dose responses of these materials were found to be compatible with commonly used feldspar and quartz compounds. The IRSL signal was shown to be linear with a radiation dose until ∼200 Gy and stable at ambient temperature, which may allow the use of such materials for dating

  5. OSL properties of anthropological bone and tooth

    Energy Technology Data Exchange (ETDEWEB)

    Meric, Niyazi [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Besevler-Ankara (Turkey)], E-mail: meric@ankara.edu.tr; Kosal, Mehmet [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Besevler-Ankara (Turkey)], E-mail: kosal@eng.ankara.edu.tr; Altay Atlihan, M. [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Besevler-Ankara (Turkey)], E-mail: atlihan@eng.ankara.edu.tr; Rabia Yuece, Ulkue [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Besevler-Ankara (Turkey)], E-mail: ulku.yuce@taek.gov.tr

    2008-06-15

    The aim of present work was to investigate whether anthropological bone and teeth can be used in dosimetric and dating studies. The radiation dose responses of anthropological human bone and pig teeth were obtained and studied using infrared stimulated luminescence (IRSL). The radiation dose responses of these materials were found to be compatible with commonly used feldspar and quartz compounds. The IRSL signal was shown to be linear with a radiation dose until {approx}200 Gy and stable at ambient temperature, which may allow the use of such materials for dating.

  6. Biological dosimetry, scopes and limitations; Dosimetria biologica, alcances y limitaciones

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [Departamento de Biologia, Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Salazar, Estado de Mexico (Mexico)

    1999-07-01

    The analysis of the aberrations in chromosomes is an alternative to establish the exposure dose to the radiation, when the information provided by the traditional physical methods is insufficient. There are diverse causes by which it can reached to apply an alternative system, such is the case of exposures of another persons to the management of radiation sources, which not carry physical dosemeter. Contrary case is to the occupational exposure personnel (OEP), what must to utilize some system for determining the exposure dose, even so can be needed the case for more information. In any case, the cells from the affected person are the alternative without the biological system be overlap to the physical, it is complementary. (Author)

  7. Thermoluminescence in medical dosimetry; Termoluminiscencia en dosimetria medica

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, T., E-mail: trivera@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

    2011-10-15

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  8. The personal dosimetry in Mexico; La dosimetria personal en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.A. [Proxtronics/ Asesoria Integral en Dosimetria Termoluminiscente S.A. de C.V., Canal de Miramontes 2030-14, Col. Educacion, 04400 Mexico D.F. (Mexico)]. e-mail: aidtsa@avantel.net

    2006-07-01

    The Personal Dosimetry in Mexico, has an approximately 30 year-old history; and it had been and it is at the moment, one of the more important resources with which the personnel that works with ionizing radiation sources counts for its protection. The Personal Dosimetry begins with the film dosimetry, technique that even continues being used at the present time by some users, and the main reason of its use is for economic reasons. At the moment this technique, it has been surpassed, by the Thermoluminescent dosimetry, which has taken a lot of peak, mainly by the technological development with which it is counted at the present time; what has given as a result that this technique becomes tip technology; that supported in the characteristic of the used materials, as the handling and processing of the information associated with the new PC, digitizer cards, software etc, what has allowed increases it potential. In this work the current necessities of the market are presented as well as an analysis of the future real necessities in Mexico, at national level, the companies that provide this service and that they spread to satisfy this necessity of the market, including the different used technologies are also mentioned. The application ranges, at the same time, of the advantages and disadvantages of the different systems of Personal Dosimetry in the market. The companies that at the moment provide the service of Personal Dosimetry, its use materials and equipment in indistinct form, for the monitoring of gamma radiation, beta particles, different qualities of x-ray radiation, and sometimes neutrons. The monitoring of the exposed personnel at the diverse sources of ionizing radiation mentioned is carried out in many occasions without having with the materials (detectors), neither the appropriate infrastructure and therefore without the quality control that guarantees a correct evaluation of the dose equivalent, as a result of the exposure to the ionizing radiations; it is for what is considered that this work is important since the main objective of the Personal Dosimetry is that of the protection of people, that is to say the one of avoiding risks in the health of the workers involved with the radiations. (Author)

  9. Dosimetry of industrial sources; Dosimetria de fuentes industriales

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R.; Rodriguez J, R.; Manzanares A, E.; Hernandez V, R.; Ramirez G, J. [Universidad Autonoma de Zacatecas, 98068 Zacatecas (Mexico); Rivera M, T. [CICATA-IPN, 11500 Mexico D.F. (Mexico)]. e-mail: fermineutron@yahoo.com

    2007-07-01

    The gamma rays are produced during the disintegration of the atomic nuclei, its high energy allows them to cross thick materials. The capacity to attenuate a photons beam allows to determine the density, in line, of industrial interest materials as the mining. By means of two active dosemeters and a TLDs group (passive dosimetry) the dose rates of two sources of Cs-137 used for determining in line the density of mining materials were determined. With the dosemeters the dose levels in diverse points inside the grave that it harbors the sources and by means of calculations the isodoses curves were determined. In the phase of calculations was supposed that both sources were punctual and the isodose curves were calculated for two situations: naked sources and in their Pb packings. The dosimetry was carried out around two sources of {sup 137}Cs. The measured values allowed to develop a calculation procedure to obtain the isodoses curves in the grave where the sources are installed. (Author)

  10. Relative dosimetry by Ebt-3; Dosimetria relativa por EBT3

    Energy Technology Data Exchange (ETDEWEB)

    De Leon A, M. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico); Hernandez O, J. O., E-mail: madla16@hotmail.com [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Mexico D. F. (Mexico)

    2015-10-15

    In the present work relative dosimetry in two linear accelerator for radiation therapy was studied. Both Varian Oncology systems named Varian Clinac 2100-Cd and MLC Varian Clinac i X were used. Gaf Chromic Ebt-3 film was used. Measurements have been performed in a water equivalent phantom, using 6 MV and 18 MV photon beams on both Linacs. Both calibration and Electron irradiations were carried out with the ionization chamber placed at the isocenter, below a stack of solid water slabs, at the depth of dose maximum (D max), with a Source-to-Surface Distance (SSD) of 100 cm and a field size of 10 cm x 10 cm. Calibration and dosimetric measurements photons were carried out under IAEA-TRS 398 protocol. Results of relative dosimetry in the present work are discussed. (Author)

  11. Dosimetry of {beta} extensive sources; Dosimetria de fuentes {beta} extensas

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E.L.; Lallena R, A.M. [Departamento de Fisica Moderna, Universidad de Granada, E-18071 Granada (Spain)

    2002-07-01

    In this work, we have been studied, making use of the Penelope Monte Carlo simulation code, the dosimetry of {beta} extensive sources in situations of spherical geometry including interfaces. These configurations are of interest in the treatment of the called cranealfaringyomes of some synovia leisure of knee and other problems of interest in medical physics. Therefore, its application can be extended toward problems of another areas with similar geometric situation and beta sources. (Author)

  12. Retrospective dosimetry in irradiated foods; Dosimetria retrospectiva en alimentos irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, T [Universidad Autonoma de Madrid, Facultad de Ciencias, Dpto. Quimica Agricola, Geologia, Geoquimica, Cantoblanco, Madrid (Spain)

    1999-07-01

    The main objective of this communication is to show the potentiality of certain minerals which accompany the foods (grasses, spices and seasonings) as potential dosemeters and its possible application in the absorbed dose calculations by the same in its hygienic sanitary treatment. (Author)

  13. Dosimetry of High-Energy Protons by Measurement of Beryllium-7 Formed in the Tissues; Dosimetrie des Protons de Haute Energie par Mesure de Beryllium-7 Forme dans les Tissus; 041e 0422 041d 041e 0421 0414 ; Dosimetria Relativa Mediante Berillo-7 Despues de Irradiar con Protones de Altas Energias (600 Mev Y 3 Gev)

    Energy Technology Data Exchange (ETDEWEB)

    Legeay, G. [Service Biologique et Veterinaire des Armees, Detache au D.P.S. (France); Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Fontenay-aux-Roses (France); Court, L.; Prat, L [Service de Sante des Armees, Detaches au D.P.S. (France); Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Fontenay-aux-Roses (France); Jeanmaire, L.; Daburon, M. L. [Commissariat a l' Energie Atomique (France); Nucleaires de Fontenay-aux-Roses, Centre d' Etudes [France; De Kerviler, H.; Tardy-Joubert, P. [Service de Protection Contre les Radiations, Centre d' Etudes Nucleaires de Saclay (France)

    1965-06-15

    compara las actividades determinadas experimentalmente y las calculadas en funcion de la energia a partir de los valores de las secciones eficaces actualmente admitidos. Dado que la irradiacion accidental del ser humano en haces protonicos es siempre localizada, se han efectuado experimentos consistentes en la irradiacion de la cabeza de conejos Fauve de Bourgogne de unos 2 kg de peso. Se comprobo que la actividad inducida en la cabeza es, en relacion a la que se observa en el resto del cuerpo, del orden de 1,8 {+-} 5. A pesar de cierta difusion el {sup 7}Be se puede detectar durante los primeros dias que siguen a la irradiacion. Por tanto, queda demostrado que este tipo de dosimetria relativa permite formarse una idea concreta del orden de magnitud de la irradiacion recibida accidentalmente. (author) [Russian] V ramkah biologicheskih jeksperimentov, provedennyh na sinhrociklotrone issledovatel'skogo jadernogo centra CERN v Zheneve s primeneniem protonov v 600 Mjev, i na sinhrotrone ''Saturn'' v issledovatel'skom jadernom centre Sakle s pomoshh'ju gamma-spektrografii, issledovalas' navedennaja radioaktivnost' u zhivyh sushhestv. I esli bol'shinstvo navedennyh radioizotopov (gamma-izluchatelej) imejut ochen' korotkij period poluraspada, to berillij-7, poluchaemyj v rezul'tate reakcij rasshheplenija na atomah kisloroda, ugleroda i azota, v chastnosti, daet pik aktivnosti, kotoryj bystro otdeljaetsja ot vsego spektra pri urovne jenergij v 479 kjev. Period poluraspada berillija-7 ravnyj 54,5 dnja pozvoljaet registrirovat' ego v techenie dostatochno prodolzhitel'nogo vremeni. Issledovanie, provedennoe Uajcarom na krysah, kotorye byli oblucheny in toto dozami mezhdu 400 i 800 rad, s protonami v 600 Mjev, i dozami 200 i 1000 rad, s protonami v 3 Gjev, daet linejnuju harakteristiku aktivnosti berillija-7 v zavisimosti ot pogloshhennoj dozy na 1 g tkani. Jeksperimental'nye rezul'taty sravnivalis' s raschetnymi, proizvedennymi s uchetom zavisimosti ot jenergii i na baze sechenij

  14. Planned Procedures for Fast Determination of Radiation Levels and Personnel Dosimetry in Connection with Radiological Accidents; Methodes de Dosimetrie Rapide du Personnel en Cas d'Accident Radiologique; 041f 041b 0410 041d 0414 ; Servicio Organizado de Determinacion Rapida de los Niveles de Radiacion y de Dosimetria del Personal en Caso de Accidente Radiologico

    Energy Technology Data Exchange (ETDEWEB)

    Edvardsson, K. -A.; Wahlberg, T. [AB Atomenergi, Studsvik (Sweden)

    1965-06-15

    medios de comunicacion con el interior y con el exterior. En materia de dosimetria individual, interesa, a la vez obtener lo antes posible los datos preliminares aproximados de la intensidad de la exposicion interna y externa, asi como, dentro de un plazo prudencial, datos bastante exactos, de la exposicion a que ha estado expuesta cada persona. Diversos equipos de determinacion de dosis, conocidos con el nombre de patrullas de reconocimiento, recorren los diversos sectores del recinto de la instalacion a fin de efectuar una evaluacion general de los riesgos. Esas patrullas que entran en accion tan pronto como se recibe la alarma estan provistas de instrumentos portatiles y recorren en automovil una serie de itinerarios previamente determinados en el emplazamiento. Los ensayos practicos realizados han puesto de manifiesto que las informaciones reunidas por las diversas patrullas llegan a la oficina central transcurridos 10-15 min despues de darse la alarma, permitiendo obtener una vision clara de los niveles de radiacion dentro y fuera de los diversos edificios. Los aparatos portatiles incluyen dispositivos para muestreo rapido del aire que funcionan segun el principio del eyector de aire. Las dosis individuales de irradiacion externa se evaluan con ayuda de dosimetros de pelicula, por activacion de dosimetros de criticidad, asi como por analisis de la actividad del pelo y de la sangre. La contaminacion interna se determina mediante antropogammametria y analisis radiometrico de las excreta. Para delimitar los campos de radiacion creados por un accidente, existen diversos puntos fijos de control equipados con dosimetros de varios tipos, a cuya lectura se procede lo antes posible despues de producirse el supuesto accidente. (author) [Russian] Obshhestvo po atomnoj jenergii Shvecii imeet special'nuju avarijnuju organizaciju, kotoraja nachinaet funkcionirovat' kak tol'ko poluchen signal o tom, chto sozdalos' chrezvychajnoe polozhenie v svjazi s bol'shoj radiacionnoj opasnost

  15. In Vivo and Air Dosimetry of Fission-Spectrum Neutrons; Dosimetrie In Vivo et dans l'Air du Spectre des Neutrons de Fission; Dozimetriya v vozdukhe i dozimetriya In Vivo nejtronov spektra deleniya; Dosimetria In Vivo y en el Aire de Neutrones de un Espectro de Fision

    Energy Technology Data Exchange (ETDEWEB)

    Mobley, T. S.; Engel, R. E.; Godden, W. R. [Kirtland Airforce Base, New Mexico (United States); Penikas, V. T. [AFIT, Wright-Patterson Air Force Base, Ohio, with Duty Station at University of Rochester, School of Medicine and Dentistry, Rochester, NY (United States)

    1964-03-15

    laterales a une distance mediane de 200 cm ou de 175 cm du centre de l ' assemblage critique. La dose de neutrons mesuree dans l ' air etait de 161 {+-} 5 ,5 rad a 200 cm et de 242 {+-} 16.6 rad a 175 cm. A ces distances, la dose gamma etait respectivement de 33 {+-} 2,4 et 42 {+-} 2,5 r. Les doses d'entree et de sortie ainsi que la dose a l ' insertion variaient selon l'elevation de temperature due aux bouffees de neutrons, la distance du reacteur, l 'orientation des feuilles par rapport au reacteur et l'epaisseur et la composition de tissus attenuants. (author) [Spanish] Con el proposito de evaluar la configuracion de la dosis profunda durante la exposicion a neutrones de un espectro de fisionalos autores han ideado un metodo de dosimetria neutronica in vivo que aplicaron a ovejas. Utilizaron para estos estudios un reactor pulsante analogo al GODIVA II del Laboratorio Cientifico de Los Alamos. Dicho conjunto funciona de forma de producir impulsos de 50 {mu}s de amplitud, medida a la mitad de la altura maxima, y un ascenso de temperatura del combustible de unos 100 Degree-Sign C. Ademas, prepararon 'apositos ' subcutaneos que contienen una lamina de oro recubierta de cadmio, una lamina de oro sin recubrir y tres dosimetros de varilla de vidrio, termoluminiscentes, en un recipiente de plomo al litio revestido de vidrio. Estos apositos se introdujeron en el tejido subcutaneo, a ambos lados del cuerpo, y sirvieron para medir el flujo integrado de neutrones termicos y la dosis gamma, a medida que la irradiacion neutronica se aplica 'lateralmente'. Los apositos abdominales se prepararon en forma semejante a los subcutaneos; constan de una esfera de boro que contiene laminas de umbral de fision (Pu, Np, U) recubiertas de cadmio, una pastilla de azufre y los mismos tres tipos de dosimetros que forman parte del aposito subcutaneo. El aposito dosimetrico se sujeto al pilar anterior del rumen del animal 18 h antes de someterlo a la exposicion. En la memoria se describe la tecnica de

  16. Nuclear Accident Dosimetry at Argonne National Laboratory; Dosimetrie dans les Cas d'Accidents Nucleaires au Laboratoire National d'Argonne; 0421 041b 0423 0416 0411 0410 0414 ; Dosimetria en Casos de Accidente Nuclear en el Laboratorio Nacional de Argonne

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L. L.; Duffy, T. L.; Sedlet, J.; O' Neil, D. P. [Argonne National Laboratory, Argonne, IL (United States)

    1965-06-15

    cellules au cuivre, a l'indium et aux composes du soufre. Les auteurs calculent la fluence totale des neutrons en utilisant le spectre corrige en conjonction avec une fonction de probabilite de capture et le resultat pour le sodium du sang. On peut alors obtenir une ou plusieurs specifications de la dose des neutrons, en appliquant la fonction de conversion appropriee aux renseignements obtenus sur le spectre. L'element de l'ensemble dosimetre primaire destine a mesurer les rayons gamma contient des baguettes fluorescentes et un dosimetre a thermoluminescence en plus du dosimetre chimique a deux phases. Le dosimetre gamma de l'ensemble secondaire est une.solution de polyacrylamide qui se degrade sous l'effet des rayons gamma. On calcule la dose absorbee a partir de la valeur mesuree du changement de viscosite de la solution. Le memoire signale les difficultes que presentent l'evaluation des resultats, le choix de l'emplacement et la stabilite pendant le stockage. Des methodes sont etablies pour le dosage du phosphore-32 dans les matieres biologiques, lequel vise a obtenir la dose de neutrons rapides, a analyser les matieres prelevees dans le milieu ambiant pour y doser les produits resultant de l'activation par les neutrons et a determiner le nombre total de fissions. Le controle administratif des operations de dosimetrie est facilite par un manuel qui enumere les emplacements des appareils, precise les methodes de manipulation et de comptage et donne les formules de calcul de la dose. (author) [Spanish] El informe resume las medidas cuya adopcion se preve actualmente en el Laboratorio Nacional de Argonne para evaluar las dosis recibidas a consecuencia de un accidente de criticidad. Discute principalmente dos tipos de dosimetro que se encuentran en el comercio e indica los resultados de calibraciones independientes que se ejecutaron en el citado laboratorio. La red primaria de dosimetria esta constituida por detectores de umbral perfeccionados en el Laboratorio Nacional de

  17. Investigating the resetting of OSL signals in rock surfaces

    DEFF Research Database (Denmark)

    Sohbati, Reza; Murray, Andrew S.; Jain, Mayank

    2011-01-01

    were insensitive. Dose recovery tests using solar simulator and IR diodes on both K-feldspar grains and solid slices taken from the inner parts of the rocks are discussed. Preheat plateau results using surface grains and slices show that significant thermal transfer in naturally bleached samples can...... be avoided by keeping preheat temperatures low. Equivalent doses from surface K-feldspar grains were highly scattered and much larger than expected (0.02 Gy to >100 Gy), while solid surface slices gave more reproducible small doses (mean = 0.17±0.02 Gy, n = 32). Neither crushing nor partial bleaching were...... factors were derived for two samples. These indicate that, for instance, bleaching at a depth of 2 mm into these samples occurs at about ∼28% of the rate at the surface. We conclude that it should be possible to derive meaningful burial doses of >1 Gy from such cobbles; younger samples would probably...

  18. OSL-thermochronometry of feldspar from the KTB borehole, Germany

    NARCIS (Netherlands)

    Guralnik, B.; Jain, M.; Herman, F.; Ankjærgaard, C.; Murray, A.S.; Valla, P.G.; Preusser, F.; King, G.E.; Chen, R.; Lowick, S.E.; Kook, M.; Rhodes, E.J.

    2015-01-01

    The reconstruction of thermal histories of rocks (thermochronometry) is a fundamental tool both in Earth science and in geological exploration. However, few methods are currently capable of resolving the low-temperature thermal evolution of the upper ~2km of the Earth’s crust. Here we introduce a

  19. OSL-thermochronometry of feldspar from the KTB borehole, Germany

    DEFF Research Database (Denmark)

    Guralnik, Benny; Jain, Mayank; Herman, Frédéric

    2015-01-01

    a new thermochronometer based on the infrared stimulated luminescence (IRSL) from feldspar, and validate the extrapolation of its response to artificial radiation and heat in the laboratory to natural environmental conditions. Specifically, we present a new detailed Na-feldspar IRSL thermochronology...... the current geothermal gradient, or (ii) inverted into a geothermal palaeogradient of 29±2 °C km−1, integrating natural thermal conditions over the last ∼65 ka. The demonstrated ability to invert a depth–luminescence dataset into a meaningful geothermal palaeogradient opens new venues for reconstructing...

  20. OSL Based Anthropomorphic Phantom and Real-Time Organ Dosimetry

    International Nuclear Information System (INIS)

    Hintenlang, David E.

    2009-01-01

    The overall objective of this project was the development of a dosimetry system that provides the direct measurement of organ doses in real-time with a sensitivity that makes it an effective tool for applications in a wide variety of health physics applications. The system included the development of a real-time readout system for fiber optic coupled (FOC) dosimeters that is integrated with a state-of-art anthropomorphic phantom to provide instantaneous measures of organ doses throughout the phantom. The small size of the FOC detectors and optical fibers allow the sensitive volume of the detector to be located at organ centroids (or multiple locations distributed through the organ) within a tissue equivalent, anthropomorphic phantom without perturbing the tissue equivalent features of the phantom. The developed phantom/dosimetry system can be used in any environment where personnel may be exposed to gamma or x-ray radiations to provide the most accurate determinations of organ and effective doses possible to date

  1. OSL Based Anthropomorphic Phantom and Real-Time Organ Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    David E. Hintenlang, Ph.D

    2009-02-10

    The overall objective of this project was the development of a dosimetry system that provides the direct measurement of organ does in real-time with a sensitivity that makes it an effective tool for applications in a wide variety of health physics applications. The system included the development of a real-time readout system for fiber optic coupled (FOC) dosimeters that is integrated with a state-of-art anthropomorphic phantom to provide instantaneous measures of organ doses throughout the phantom. The small size of the FOC detectors and optical fibers allow the sensitive volume of the detector to be located at organ centroids (or multiple locations distributed through the organ) within a tissue equivalent, anthropomorphic phantom without perturbing the tissue equivalent features of the phantom. The developed phantom/dosimetry system can be used in any environment where personnel may be exposed to gamma or x-ray radiations to provide the most accurate determinations of organ and effective doses possible to date.

  2. Preparation and dosimetry of radiotherapeutic particles for arthropaties; Preparacion y dosimetria de particulas radioterapeuticas para artropatias

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Z, M A [Departamento de Medicina Nuclear, Instituto Nacional de Pediatria (Mexico); Ferro F, G [Departamento de Materiales Radiactivos, Instituto nacional de Investigaciones Nucleares, Salazar, Estado de Mexico C.P. 52045 (Mexico); Rivera M, T; Azorin N, J [Departamento de Fisica, UAM Iztapalapa, Mexico D.F. (Mexico)

    1999-07-01

    It was developed a new formulation of macro aggregates of Samarium 153 ({sup 153} Sm-MH) for the arthropaties treatment. The radio pharmaceutic was prepared by reaction of Samarium 153 chloride (SmCl{sub 3}) in aqueous environment with sodium boron hydride in NaOH 0.5 N. The microscopic analysis shown that the particles have an average size of 4% m (range 1-14 {mu} m). The velocity of sedimentation was 0.008 cm/min with high stability in vitro in human serum. The biological studies in healthy rabbits, shown that the complex is retained inside the articulation still eight days after of the administration of the radiopharmaceutical. Likewise, it is presented the data of absorbed dose in the different target organs, which was determined by thermoluminescent dosimetry (TLD) through the use of a REMCAL phantom (radiation equivalent manikin calibration). (Author)

  3. Implementation of an alanine dosimetry service; Puesta en marcha de un servicio de dosimetria de alanima

    Energy Technology Data Exchange (ETDEWEB)

    Gago Arias, A.; Nunez Pelaez, N.; Peteiro Vilaseco, E.; Gomez Rodriguez, F.; Gonzalez Castano, D. M.

    2011-07-01

    This work facing the implementation of an alanine dosimetry service, linked to the installation of Co{sub 6}0 Radio physics Laboratory (LP) and Paramagnetic Resonance Service of the University of Santiago de Compostela (USC).

  4. Update Dosimetry Service internal staff Tecnatom; Actualizacion del servicio de dosimetria personal interna de TECNATOM

    Energy Technology Data Exchange (ETDEWEB)

    Bravo, B.; Marchena, P.; Alonso, A.; Navarro, E.; Serrano, E.

    2010-07-01

    The beginning of decommissioning of nuclear facilities and other industrial national context conditions have been a very significant increase in the need for such services, which have been almost overwhelmed by the demand. To provide a solution to this situation, Tecnatom decided to run as a new internal dosimetry service indirect measures to complement its renowned capabilities of direct measures. To perform this task, Tecnatom has signed a collaboration agreement with the Laboratory of Radiochemistry of Geocisa, all with the objective of characterizing contamination by alpha emitters or beta different analytical techniques.

  5. Calibration curves for biological dosimetry; Curvas de calibracion para dosimetria biologica

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail cgc@nuclear.inin.mx

    2004-07-01

    The generated information by the investigations in different laboratories of the world, included the ININ, in which settles down that certain class of chromosomal leisure it increases in function of the dose and radiation type, has given by result the obtaining of calibrated curves that are applied in the well-known technique as biological dosimetry. In this work is presented a summary of the work made in the laboratory that includes the calibrated curves for gamma radiation of {sup 60} Cobalt and X rays of 250 k Vp, examples of presumed exposure to ionizing radiation, resolved by means of aberration analysis and the corresponding dose estimate through the equations of the respective curves and finally a comparison among the dose calculations in those people affected by the accident of Ciudad Juarez, carried out by the group of Oak Ridge, USA and those obtained in this laboratory. (Author)

  6. Design of a system for neutrons dosimetry; Diseno de un sistema para dosimetria de neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Ceron, P.; Rivera, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Paredes G, L. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Azorin, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Sanchez, A. [IPN, Escuela Superior de Fisica y Matematicas, Av. Instituto Politecnico Nacional s/n, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico); Vega C, H. R., E-mail: victceronr@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-08-15

    At the present time diverse systems of detection of neutrons exist, as proportional counters based on BF{sub 3}, He{sub 3} and spectrometers of Bonner spheres. However, the cost and the complexity of the implementation of these systems put them far from the reach for dosimetric purposes. For these reasons a system of neutrons detection composed by a medium paraffin moderator that forms a 4π (spheres) arrangement and of several couples of thermoluminescent dosimeters TLD 600/TLD 700. The response of the system presents a minor repeatability to 5% in several assays when being irradiated with a {sup 239}PuBe source and a deviation of 13.8% in the Tl readings of four different spheres. The calibration factor of the system with regard to the neutrons source which was of 56.2 p Sv/nc also was calculated. These detectors will be used as passive monitors of photoneutrons in a radiotherapy room with lineal accelerator of high energy. (Author)

  7. Dosimetry with slow films in Interventional Radiology; Dosimetria con peliculas lentas en Radiologia Intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Ten, J.I.; Guibelalde, E.; Fernandez, J.M.; Canevaro, L.; Ramirez, R.; Vano, E. [Grupo de Fisica Medica. Departamento de Radiologia. Facultad de Medicina. Universidad Complutense de Madrid. Martin Lagos s/n CP 28040, Madrid (Spain)

    1998-12-31

    In this work it is presented a method for evaluation of patients doses in Interventional Radiology (RI). The method proposed in this work allows the simultaneous valoration of the product dose-area (PDA), the dose in the patient skin (DES) and the distribution of the irradiated fields, all of they together with their corresponding dose levels. The latter sometimes can be essential since the possible damages in skin depend not only of the doses, but also the irradiated area. The method has been resulted adequate for to evaluate doses to patients in Interventional Radiology procedures. It was possible to apply it as a routine form seeing that its not interfering significantly in the normal development of the medical intervention. The fundamental advantages of this dosimetric method in relation with the unique PDA measure or with the utilization of TLD is that it provide information about the total irradiated area, distribution and length of fields, collimation and wedge used besides that allow to determine the most irradiated zone. The visualization of the irradiated regions and the length fields utilized suggest the possibility to optimize the realization protocols of the interventional procedure in the cases in which it is considered that the doses have been very elevated. (Author)

  8. Advances in electron dosimetry of irregular fields; Avances en dosimetria de electrones de campos irregulares

    Energy Technology Data Exchange (ETDEWEB)

    Mendez V, J. [Departamento de Radioterapia, Instituto de Enfermedades Neoplasicas, Avenida Angamos Este 2520, Lima 34 (Peru)

    1998-12-31

    In this work it is presented an advance in Electron dosimetry of irregular fields for beams emitted by linear accelerators. At present diverse methods exist which are coming to apply in the Radiotherapy centers. In this work it is proposed a method for irregular fields dosimetry. It will be allow to calculate the dose rate absorbed required for evaluating the time for the treatment of cancer patients. Utilizing the results obtained by the dosimetric system, it has been possible to prove the validity of the method describe for 12 MeV energy and for square field 7.5 x 7.5 cm{sup 2} with percentile error less than 1 % . (Author)

  9. Thermoluminescent dosimetry in computed tomography for pediatric patients; Dosimetria termoluminiscente en tomografia computada para pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Medrano S, A. C.; Medina A, O.; Hidalgo T, S.; Azorin N, J., E-mail: alicesar1993@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2015-10-15

    Computed tomography (CT) in conjunction with interventional radiology, is considered as high-dose radiological procedure, so the optimization of the dose is necessary. Exposure to ionizing radiation in pediatric CT is of particular interest because the children are up to 10 times more sensitive to radiation than adults, the late somatic and genetic effects of radiation. The exposure and risk associated with ionizing radiation in CT is best characterized by the absorbed dose to each organ. Thermoluminescent dosimeters of LiF: Mg, Ti are best suited for this purpose due to its characteristics such as high sensitivity, small size and its equivalence with the tissue. The results of dose measurements -in vivo- to the three types of CT studies (skull, thorax and abdomen) are presented. These results indicate that lower doses were obtained in skull study, while the highest was one of abdomen. (Author)

  10. Dosimetry of ionizing radiations by Electron paramagnetic resonance; Dosimetria de radiaciones ionizantes por resonancia paramagnetica electronica

    Energy Technology Data Exchange (ETDEWEB)

    Azorin N, J [UAM-I, Av. San Rafael Atlixco 186, 09340 Mexico D.F. (Mexico)

    2005-07-01

    In this work, some historical and theoretical aspects about the Electron Paramagnetic Resonance (EPR), its characteristics, the resonance detection, the paramagnetic species, the radiation effects on inorganic and organic materials, the diagrams of the instrumentation for the EPR detection, the performance of an EPR spectrometer, the coherence among EPR and dosimetry and, practical applications as well as in the food science there are presented. (Author)

  11. Improvements in the Tl dosimetry for Radiotherapy; Mejoras en la dosimetria Tl para Radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Bustos, S.; Velez, G.; Rubio, M. [CEPROCOR. Arenales 230 Juniors Cordoba 5000 (Argentina)

    1998-12-31

    The thermoluminescent dosimetry (TLD) in vivo has been demonstrated to be one of the most reliable for the control of radiotherapeutic treatments, but the delay in the response is the main disadvantage in its applicability. In this work are presented important improvements and it is demonstrated that maintaining the accuracy and reliability of the technique, it is possible to accelerate the response times at a few hours. To realize this work is utilized a lecturer Harshaw 4000, dosemeters LiF-TLD-100 chips (3.1 x 3.1 x 0.89 mm{sup 3}) and rods (1 x 1 x 6 mm{sup 3}). With the implementation of a glow curve analysis program developed in CIEMAT, its obtained a Tl peaks separation in such manner rapid and accurate, by that the thermal treatment of dosemeters may be reduced at one unique annealing pre-irradiation for 1 hr at 400 Centigrade. It is realized a periodical and individual calibration of the TLD and a study of the factors which influencing the ratio Tl signal-dose as linearity, correction by energy, directional response and pride of Tl signal. the results of this study are introducing in a calculation list specially designed and which allows to obtain absorbed dose by TLD starting of the dates (dosimetric peaks area) which appear of the glow curves analysis. The dose is obtained with an accuracy less than 5 %. The dosemeters already irradiated (in vivo) are analysed and informed in only four hours, allowing a greater control of the treatment and a correction of the possible errors for the next session, still in bi fractional treatments. The method implemented results thus accurate, rapid and reliable. (Author)

  12. Thermoluminescent dosimetry in fluoroscopy of pediatric patients; Dosimetria termoluminiscente en fluoroscopia de pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia V, E.; Azorin N, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Departamento de Fisica, San Rafael Atlixco 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico); Hidalgo T, S.; Dies S, P., E-mail: azorin@xanum.uam.mx [Hospital Infantil de Mexico Federico Gomez, Dr. Marquez 162, Col. Doctores, 06720 Ciudad de Mexico (Mexico)

    2016-10-15

    The use of thermoluminescent dosimeters in the area of medical physics and especially in radiology is of paramount importance to guarantee the quality of a particular study, which for this reason the need to verify by means of measurements of peripheral dose in studies of esophagogastroduodenal series by fluoroscopy using TLD of LiF:Mg, Ti. For this the necessary measurements were carried out directly in patients of the Children s Hospital of Mexico Federico Gomez. Previously characterized the dosimeters were used the graphs of the linear equation to obtain the absorbed dose of each dosimeter and was found that the values of the absorbed dose in each patient changes for various reasons like the anatomy, thickness of the tissues, age and exposure time during the study and was verify that none of the studies performed on patients exceeded dose levels that could affect healthy organs. (Author)

  13. Internal dosimetry in nuclear medicine procedures; Dosimetria interna por procedimientos en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Carrera Magarino, F.; Salgado Garcia, C.; Ruiz Manzano, P.; Rivas Ballarin, M. A.; Jimenez Hefernan, A.; Sanchez Segovia, J.

    2011-07-01

    The Department of Radio Physics and Radiation Protection, University Hospital Lozano Blesa Zaragoza presented a calculus textbook to estimate patient doses in diagnostic nuclear medicine. In this paper present an updated version referred Book of calculation.

  14. Course on internal dosimetry in nuclear medicine; Curso de dosimetria interna en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This documentation was distributed to the participants in the Course of Internal Dosimetry in Nuclear Medicine organised by the Nuclear Regulatory Authority (ARN) of Argentina and held in Buenos Aires, Argentina, August 9-13, 2004. The course was intended for people from IAEA Member States in the Latin American and Caribbean region, and for professionals and workers in medicine, related with the radiation protection. Spanish and English were the languages of the course. The following subjects were covered: radioprotection of the patient in nuclear medicine; injuries by ionizing radiations; MIRD methodology; radiation dose assessment in nuclear medicine; small scale and microdosimetry; bone and marrow dose modelling; medical internal dose calculations; SPECT and image reconstruction; principles of the gamma camera; scattering and attenuation correction in SPECT; tomography in nuclear medicine.

  15. Personnel thermoluminescent dosimetry of plane pilots; Dosimetria personal termoluminiscente de pilotos aviadores

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, J.C. [Universidad Nacional Autonoma de Mexico, Facultad de Ciencias, 04510 Mexico D.F. (Mexico); Rivera M, T. [Universidad Autonoma Metropolitana Iztapalapa, Departamento de Fisica, 09340 Mexico D.F. (Mexico); Azorin N, J. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, 11500 Mexico D.F. (Mexico)

    1999-07-01

    In this work are presented the results of the research realized in the pilots of commercial planes of the different flight equipment existing. The results obtained show that the pilots receive during their work, doses of ionizing radiation greater than the limit recommended by the International Commission of Radiological Protection. (Author)

  16. Retrospective dosimetry of nail by Electron Paramagnetic Resonance; Dosimetria retrospectiva de unha por Ressonancia Paramagnetica Eletronica

    Energy Technology Data Exchange (ETDEWEB)

    Giannoni, Ricardo A., E-mail: giannoni@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Rodrigues Junior, Orlando, E-mail: rodrijr@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The purpose of this study is to characterize samples of human nails, subjected to irradiation of high doses through Technical Electron Paramagnetic Resonance (EPR). The goal is to establish a dose/response relationship in order to assess dose levels absorbed by individuals exposed in radiation accidents situations, retrospectively. Samples of human nails were irradiated with gamma radiation, and received a dose of 20 Gy. EPR measurements performed on samples before irradiation identified EPR signals associated with defects caused by the mechanical action of the sample collection. After irradiation other species of free radicals, associated with the action of gamma radiation, have been identified.

  17. Thermoluminescent dosemeter in a X-ray diffractometer; Dosimetria termoluminiscente en un difractometro de rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza A, D.; Gonzalez M, P.; Falcon B, T. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico); Castano, V.M. [Instituto de Fisica, UNAM, Laboratorio Juriquilla, A.P. 1-1010, C.P. 76001, Queretaro (Mexico)

    1999-07-01

    In this work it was presented the results obtained of the dosimetry which was realized in a X-ray diffractometer for powders, trademark Siemens D5000, using the thermoluminescent signal generated by the X-rays in the commercial dosemeter TLD-100 of Harshaw, US. In according to the results obtained, the radiation quantity received by an analysed material in the diffractometer, will be proportional to exposure time and it can vary from unities until tenths of grays. These results are very outstanding when are analysed crystalline materials in a diffractometer, for knowing the present crystalline phases, mainly if these are highly sensitive to the ionizing radiation, as it is the case of the thermoluminescent materials. (Author)

  18. Answer to request on the ININ internal dosimetry; Respuesta a encuesta sobre dosimetria interna del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1999-05-15

    In this report it is presented the reply to CNSNS asking for information about the methodology for the evaluation of the occupational dose due to internal contamination. The characteristics of the installation, type and dimensions of the shield room, construction materials, type of detecting, calibration geometries, type of used phantom, intervals of energy of the calibration, type of routine measurements, detection limit for Cs-137 and Co-60, code to carry out the analysis of the spectra, evaluation of the measurement data, whole body system type armchair with anthropomorphic phantom, whole body system of vertical scanning, distribution and location diagram of the internal dosimetry laboratory there are among the treated aspects. (Author.

  19. Dosimetry of a Cesium 137 source; Dosimetria de una fuente de Cesio 137

    Energy Technology Data Exchange (ETDEWEB)

    Torres R, J.G.; Manzanares A, E.; Vega C, H.R. [Unidades Academicas de Estudios Nucleares, Universidad de Zacatecas (Mexico)

    2005-07-01

    It was carried out a dosimetric study of a source of Cesium 137 used in investigations of Radiobiology. This radionuclide has a half life of 30.07 years and it emits photons of 661.657 keV with a probability of 85.2%. The source has been used in a series of experiments trending to observe the cellular response before the gamma rays, as well as for the calibration of equipment of radiological protection. For such reason it is important to determine the dosimetric properties. In this work it was determined the absorbed dose that this source takes when being placed in the center from a methylmethacrylate badge to three distances, 5, 10 and 15 cm. The dose was measured with thermoluminescent dosemeters and it was calculated by means of Monte Carlo method, also was derived an expression that allows to determine the dose starting from the information of the activity of the source and of the distance regarding the same one. (Author)

  20. Quantification of termite bioturbation in a savannah ecosystem: Application of OSL dating

    DEFF Research Database (Denmark)

    Kristensen, Jeppe Ågård; Thomsen, Kristina Jørkov; Murray, Andrew

    2015-01-01

    transport soil from depth to the surface to construct termitaria. Over time, erosion levels these mounds and returns the sediment to the soil surface. These two processes of construction and erosion together represent an upward “conveyor belt” sediment transport process. We find that the sediment...

  1. A portable system for the measurement of sediment OSL in the field

    DEFF Research Database (Denmark)

    Poolton, N.R.J.; Bøtter-Jensen, L.; Wintle, A.G.

    1994-01-01

    regeneration provided by cold-running gas discharge lamps. The modular form means that the mobile system can be built up into a full luminescence excitation/emission spectrometer useful in the wavelength range 380-1000 nm, thus allowing both quartz and feldspar to be analysed. The characteristics...

  2. Testing OSL failures against a regional glaciation chronology from southern Scandinavia

    DEFF Research Database (Denmark)

    Houmark-Nielsen, Michael

    2008-01-01

    Middle Weichselian periglacial strata and Last Glacial Maximum (LGM) ice proximal deposits showing pre-LGM ages. Suggestions are given as to how the depositional environment may influence the dating results. Even though independent dating anchors the marine Cyprina clay and last interglacial peat bogs...

  3. Use of the LM-OSL technique for the detection of partial bleaching in quartz

    DEFF Research Database (Denmark)

    Larsen, N.A.; Bulur, E.; Bøtter-Jensen, L.

    2000-01-01

    governing the ease-of-bleaching is the photoionization cross-section of the trap involved. The concept is also demonstrated in a model study from which very good agreement with the experimental observations has been found. Potential applications of the technique to dating are discussed. (C) 2000 Elsevier...

  4. Sources of variability in OSL dose measurements using single grains of quartz

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, A.S.; Bøtter-Jensen, L.

    2005-01-01

    spread. In this preliminary study, dose distributions have been studied using single grains of heated and laboratory irradiated quartz. By heating the sample, the contribution from incomplete zeroing was excluded and at the same time the sample was sensitised. The laboratory gamma irradiation...

  5. A continuous OSL scanning method for analysis of radiation depth-dose profiles in bricks

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Jungner, H.; Poolton, N.R.J.

    1995-01-01

    This article describes the development of a method for directly measuring radiation depth-dose profiles from brick, tile and porcelain cores, without the need for sample separation techniques. For the brick cores, examples are shown of the profiles generated by artificial irradiation using...... the different photon energies from Cs-137 and Co-60 gamma sources; comparison is drawn with both the theoretical calculations derived from Monte Carlo simulations, as well as experimental measurements made using more conventional optically stimulated luminescence methods of analysis....

  6. Luminescence dating on Mars: OSL characteristics of Martian analogue materials and GCR dosimetry

    DEFF Research Database (Denmark)

    Jain, M.; Andersen, C.E.; Bøtter-Jensen, L.

    2006-01-01

    , and sedimentary precipitates such as sulphates and chlorides. We present here a preliminary investigation of the luminescence characteristics (sensitivity, dose response, fading) of some Martian analogue mineral and rock samples. These materials are likely to be zeroed by the solar UV light (200-300nm) under sub...

  7. Computerised curve deconvolution of TL/OSL curves using a popular spreadsheet program.

    Science.gov (United States)

    Afouxenidis, D; Polymeris, G S; Tsirliganis, N C; Kitis, G

    2012-05-01

    This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the GLOw Curve ANalysis INtercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters.

  8. Validating post IR-IRSL dating on K-feldspars through comparison with quartz OSL ages

    NARCIS (Netherlands)

    Kars, R.H.; Busschers, F.S.; Wallinga, J.

    2012-01-01

    Recent developments have opened up the possibilities of using potassium feldspar for dating Pleistocene sediments; a stable (less-fading) part of the infrared stimulated luminescence (IRSL) signal can be selected by largely depleting the unstable part of the IR signal, using a combination of thermal

  9. Application of the optically stimulated luminescence (OSL) technique for mouse dosimetry in micro-CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Vrigneaud, Jean-Marc; Courteau, Alan; Oudot, Alexandra; Collin, Bertrand [Department of Nuclear Medicine, Centre Georges-François Leclerc, 1 rue Professeur Marion, Dijon 21079 Cedex (France); Ranouil, Julien [Landauer Europe, 33 avenue du Général Leclerc, Fontenay-aux-Roses 92266 Cedex (France); Morgand, Loïc; Raguin, Olivier [Oncodesign, 20 rue Jean Mazen, Dijon 21076 Cedex (France); Walker, Paul [LE2i CNRS UMR 5158, Faculty of Medicine, BP 87900, 21079 Dijon Cedex (France); Brunotte, François [Department of Nuclear Medicine, Centre Georges-François Leclerc, 1 rue Professeur Marion, Dijon 21079 Cedex, France and LE2i CNRS UMR 5158, Faculty of Medicine, BP 87900, 21079 Dijon Cedex (France)

    2013-12-15

    Purpose: Micro-CT is considered to be a powerful tool to investigate various models of disease on anesthetized animals. In longitudinal studies, the radiation dose delivered by the micro-CT to the same animal is a major concern as it could potentially induce spurious effects in experimental results. Optically stimulated luminescence dosimeters (OSLDs) are a relatively new kind of detector used in radiation dosimetry for medical applications. The aim of this work was to assess the dose delivered by the CT component of a micro-SPECT (single-photon emission computed tomography)/CT camera during a typical whole-body mouse study, using commercially available OSLDs based on Al{sub 2}O{sub 3}:C crystals.Methods: CTDI (computed tomography dose index) was measured in micro-CT with a properly calibrated pencil ionization chamber using a rat-like phantom (60 mm in diameter) and a mouse-like phantom (30 mm in diameter). OSLDs were checked for reproducibility and linearity in the range of doses delivered by the micro-CT. Dose measurements obtained with OSLDs were compared to those of the ionization chamber to correct for the radiation quality dependence of OSLDs in the low-kV range. Doses to tissue were then investigated in phantoms and cadavers. A 30 mm diameter phantom, specifically designed to insert OSLDs, was used to assess radiation dose over a typical whole-body mouse imaging study. Eighteen healthy female BALB/c mice weighing 27.1 ± 0.8 g (1 SD) were euthanized for small animal measurements. OLSDs were placed externally or implanted internally in nine different locations by an experienced animal technician. Five commonly used micro-CT protocols were investigated.Results: CTDI measurements were between 78.0 ± 2.1 and 110.7 ± 3.0 mGy for the rat-like phantom and between 169.3 ± 4.6 and 203.6 ± 5.5 mGy for the mouse-like phantom. On average, the displayed CTDI at the operator console was underestimated by 1.19 for the rat-like phantom and 2.36 for the mouse-like phantom. OSLDs exhibited a reproducibility of 2.4% and good linearity was found between 60 and 450 mGy. The energy scaling factor was calculated to be between 1.80 ± 0.16 and 1.86 ± 0.16, depending on protocol used. In phantoms, mean doses to tissue over a whole-body CT examination were ranging from 186.4 ± 7.6 to 234.9 ± 7.1 mGy. In mice, mean doses to tissue in the mouse trunk (thorax, abdomen, pelvis, and flanks) were between 213.0 ± 17.0 and 251.2 ± 13.4 mGy. Skin doses (3 OSLDs) were much higher with average doses between 350.6 ± 25.3 and 432.5 ± 34.1 mGy. The dose delivered during a topogram was found to be below 10 mGy. Use of the multimouse bed of the system gave a significantly 20%–40% lower dose per animal (p < 0.05).Conclusions: Absorbed doses in micro-CT were found to be relatively high. In micro-SPECT/CT imaging, the micro-CT unit is mainly used to produce a localization frame. As a result, users should pay attention to adjustable CT parameters so as to minimize the radiation dose and avoid any adverse radiation effects which may interfere with biological parameters studied.

  10. Clinical characterization of OSL dosimeters for use in dosimetry of teletherapy beams in conventional fractionation

    International Nuclear Information System (INIS)

    Lopez V, A.; Gutierrez M, J. G.; Rivera M, T.; Velazquez T, J. J.

    2015-10-01

    Optically stimulated materials are increasingly used for dosimetry in clinical settings; to be sure of the obtained reading their proper clinical characterization is necessary. Is important to know the homogeneity of a batch, reproducibility, be exposed to the same conditions of irradiation repeatedly and other dependences that could present such as energy, angular, the type of radiation which are exposed and the dose deposited in them. For characterization they were designed and implemented tests for each of the factors of interest, taking into account the need for them (calculations, manufacture of mannequins, conditions, practicality, etc.) It was shown that we can apply this dosimetry in clinical practice within a radiotherapy center, relying on the readings and practicality. (Author)

  11. Alpha efficiency determination for OSL of quartz extracted from Chinese loess

    International Nuclear Information System (INIS)

    Lai Zhongping; Zoeller, Ludwig; Fuchs, Markus; Brueckner, Helmut

    2008-01-01

    We report here the estimates of alpha efficiency for fine grain quartz extracted from Chinese loess using the SAR protocol. For the seven samples, the α-values range from 0.028 to 0.038 with an average of 0.035±0.001. The annealed quartz (450 deg. C, 45 min) has an α-value of 0.030±0.001 which is similar to the α-value of 0.029±0.001 for the non-annealed quartz extracts, suggesting that the α-value is independent of the quartz's thermal history for this sample. We suggest that an α-value of 0.035±0.003 can be adopted for quartz extracted from Chinese loess when calculating the environmental dose rate

  12. Interlaboratory beta source calibration using TL and OSL on natural quartz

    DEFF Research Database (Denmark)

    Goksu. H.Y.; Bailiff, I.K.; Bøtter-Jensen, L.

    1995-01-01

    Laboratory at GSF using a Go-60 source as well as the in situ measurements with an ionization chamber, calibrated to the primary standards of PTB Braunschweig. Irradiated and unirradiated quartz was distributed to the five laboratories and although different procedures were used for thermoluminescence...

  13. Computerised curve deconvolution of TL/OSL curves using a popular spreadsheet program

    International Nuclear Information System (INIS)

    Afouxenidis, D.; Polymeris, G. S.; Tsirliganis, N. C.; Kitis, G.

    2012-01-01

    This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the Glow Curve Analysis Intercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters. (authors)

  14. Sources of variability in OSL dose measurements using single grains of quartz

    International Nuclear Information System (INIS)

    Thomsen, K.J.; Murray, A.S.; Boetter-Jensen, L.

    2005-01-01

    In luminescence-based measurements of dose distributions in unheated mineral samples, the observed spread in dose values is usually attributed to four main factors: fluctuations in the number of photons counted, incomplete zeroing of any prior trapped charge (including signals arising from thermal transfer), heterogeneity in dosimetry, and instrument reproducibility. For correct interpretation of measured dose distributions in retrospective dosimetry, it is important to understand the relative importance of these components, and to establish whether other factors also contribute to the observed spread. In this preliminary study, dose distributions have been studied using single grains of heated and laboratory irradiated quartz. By heating the sample, the contribution from incomplete zeroing was excluded and at the same time the sample was sensitised. The laboratory gamma irradiation was designed to deliver a uniform dose to the sample. Thus it was anticipated that statistical fluctuations in the number of photons counted and instrument reproducibility, both quantifiable entities, should be able to account for all the observed variance in the measured dose distributions. We examine this assumption in detail, and discuss the origins and importance of the residual variance in our data

  15. Type tests to the automatic system of thermoluminescent dosimetry acquired by the CPHR for personnel dosimetry; Pruebas tipo al sistema de dosimetria termoluminiscente automatico adquirido por el CPHR para dosimetria personal

    Energy Technology Data Exchange (ETDEWEB)

    Molina P, D.; Pernas S, R. [Centro de Proteccion e Higiene de las Radiaciones (CPHR), Calle 20, No. 4113 e/ 41 y 47, Miramar, Ciudad de la Habana (Cuba)]. e-mail: daniel@cphr.edu.cu

    2005-07-01

    The CPHR individual monitoring service acquired an automatic RADOS TLD system to improve its capacities to satisfy the increasing needs of their national customers. The TLD system consists of: two automatic TLD reader, model DOSACUS, a TLD irradiator and personal dosimeters card including slide and holders. The dosimeters were composed by this personal dosimeters card and LiF: Mg,Cu,P (model GR-200) detectors. These readers provide to detectors a constant temperature readout cycle using hot nitrogen gas. In order to evaluate the performance characteristics of the system, different performance tests recommended by the IEC 1066 standard were carried out. Important dosimetric characteristics evaluated were batch homogeneity, reproducibility, detection threshold, energy dependence, residual signal and fading. The results of the tests showed good performance characteristics of the system. (Author)

  16. Type tests to the automatic thermoluminescent dosimetry system acquired by the CPHR for personal dosimetry; Pruebas tipo al sistema de dosimetria termoluminiscente automatico adquirido por el CPHR para dosimetria personal

    Energy Technology Data Exchange (ETDEWEB)

    Molina P, D.; Pernas S, R.; Martinez G, A. [Centro de Proteccion e Higiene de las Radiaciones (CPHR), Calle 20 No. 4113 e/41 y 47. Playa, C.P. 11300, A.P. 6195, C.P. 10600 La Habana (Cuba)

    2006-07-01

    The CPHR individual monitoring service acquired an automatic RADOS TLD system to improve its capacities to satisfy the increasing needs of their national customers. The TLD system consists of: two automatic TLD reader, model DOSACUS, a TLD irradiator and personal dosimeters card including slide and holders. The dosimeters were composed by this personal dosimeters card and LiF:Mg,Cu,P (model GR-200) detectors. These readers provide to detectors a constant temperature readout cycle using hot nitrogen gas. In order to evaluate the performance characteristics of the system, different performance tests recommended by the IEC 1066 standard were carried out. Important dosimetric characteristics evaluated were batch homogeneity, reproducibility, detection threshold, energy dependence, residual signal and fading. The results of the tests showed good performance characteristics of the system. (Author)

  17. Use of radiological evaluation system from the Instituto de Radioprotecao e Dosimetria in the analysis of recent radiation accidents; Utilizacao do sistema de avaliacao radiologica do Instituto de Radioprotecao e Dosimetria na analise de acidentes radiologicos recentes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rodolfo Julio da

    2013-07-01

    The response to an emergency situation involving ionizing radiation requires the joint participation of professionals from various kind of knowledge, belonging to public and private organizations (in the local, state and federal levels). The theme radiation tends to be an additional challenging factor - considering that it's, usually, remembered for its macabre and ominous aspect, in spite of the benefits provided by it - which makes the implementation of actions to protect the public, emergency professionals, the environment and property, very difficult. To this, we can add the complicating factor that, in most cases, the technician (holder of basic or advanced on the subject) is far !Tom the place where this action unfolds. The accident/incident takes the form of a radioactive source (sometimes orphaned, one that gone astray or even stolen) that is found by a person unaware of the risks to which they are being exposed or, let not forget about it, the non-observance of safety standards in industries and workplaces, by their own operators. Thus, before integrating emergency response plans with conventional plans specific to the prompt response to radiological emergencies, it is necessary that some measures had been anticipated and that some actions had, already, been planned - with the intention of mitigate health, psychological and economical damage, in ali of kind. To do this, since in the course of the second decade of the second millennium, and since you own a portable personal computer (Note or Netbook), or even with a mobile device (cellular) with a bit more resources, both of them previously updated, a responder (or even a qualified technician that is next to that fact) may already guide, at least, about a safety distances !Tom the source. Since he had knowledge about some characteristics of the source (its individual data), he can plan ahead about the possible serious situation that unfolds itself and emergency responders will find, when it get to the site. With the situation assessments done, the formal emergency team triggered will can prepare itself (with personnel and technical-materials facilities) to resolve the incident in the shortest time and with the least possible risks. (author)

  18. Computerized dosimetry of I-125 sources model 6711; Dosimetria computarizada de las fuentes de I-125 modelo 6711

    Energy Technology Data Exchange (ETDEWEB)

    Isturiz, J [Centre de Radiotherapie du Parc, Dijon (France)

    2001-07-01

    It tries on: physical presentation of the sources; radiation protection; mathematical model of I-125 source model 6711; data considered for the calculation program; experimental com probation of the dose distribution; exposure rate and apparent activity; techniques of the use given to the sources I-125; and the calculation planning systems. [Spanish] Trata sobre presentacion fisica de las fuentes, radioproteccion, modelo matematico de las fuentes I-125 modelo 6711, datos considerados en el programa de calculo, comprobacion experimental de la distribucion de dosis, tasa de exposicion y actividad aparente, tecnicas de utilizacion de las fuentes I-125; y los sistemas de planificacion del calculo de las dosis.

  19. Dosimetry of wires and single ribbons of Iridium 192; Dosimetria de alambres y ribbons individuales de Iridio-192

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucco, L.D. [Centro Medico Nuclear S.R.L. San Juan (Argentina)

    1998-12-31

    The objective of this work is in order to present in table formats the dosimetry of wires and single ribbons of Iridium with lengths 1-12 cm for each one linear source along the bisector which is perpendicular at tissue sources (water) computed for linear activity 1 mCi/cm in the case of wires, and 1 mCi/seed for ribbons. The above tables are of direct use, adaptable at particular cases so they facilitate logarithmic graphics of doses in function of the distance for interpolation and use in the treatments planning. It was shown that for two sources with identical linear activity and total length, one of the equidistant seeds at 1 cm (ribbon) and one wire on the other hand, the differences in dose rates in near positions can be about the 15% so corroborating that it is not possible to use wire tables for seeds neither vice versa. Moreover it was elaborated tables of practical direct use for dose rate in water at c Gy/hr for wires and Ribbons 1-12 cm length and from 0.5-10 cm of distance in the perpendicular bisector at the Iridium implant. (Author)

  20. Development of a guidance guide for dosimetry in computed tomography; Desenvolvimento de um guia orientativo para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Ladyjane Pereira

    2016-07-01

    Due to frequent questions from users of ionization chambers pencil type calibrated in the Instrument Calibration Laboratory of the Institute of Energy and Nuclear Research (LCI - IPEN), on how to properly apply the factors indicated in their calibration certificates, a guide was prepared guidance for dosimetry in computed tomography. The guide includes guidance prior knowledge of half value layer (HVL), as it is necessary to know the effective beam energy for application quality for correction factor (kq). The evaluation of HVL in TC scanners becomes a difficult task due to system geometry and therefore a survey was conducted of existing methodologies for the determination of HVL in clinical beams Computed Tomography, taking into account technical, practical and economic factors. In this work it was decided to test a Tandem System consists of absorbing covers made in the workshop of IPEN, based on preliminary studies due to low cost and good response. The Tandem system consists of five cylindrical absorbing layers of 1mm, 3mm, 5mm, 7mm and 10mm aluminum and 3 cylindrical absorbing covers 15mm, 25mm and acrylic 35mm (PMMA) coupled to the ionization chamber of commercial pencil type widely used in quality control tests in dosimetry in clinical beams Computed tomography. Through Tandem curves it was possible to assess HVL values and from the standard curve pencil-type ionization chamber, Kq find the appropriate beam. The elaborate Guide provides information on how to build the calibration curve on the basis of CSR, to find the Kq and information for construction Tandem curve, to find values close to CSR. (author)

  1. Calculation of absorbed dose in water by chemical Fricke dosimetry; Calculo de dose absorvida na agua por dosimetria quimica Fricke

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Adenilson Paiva, E-mail: adenilson-fisica@hotmail.com.br [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil); Meireles, Ramiro Conceicao [Fundacao do Cancer, Rio de Janeiro, RJ (Brazil)

    2016-07-01

    This work is the result of a laboratory activity performed in Radiological Sciences Laboratory (CRL), linked to the State University of Rio de Janeiro (UERJ). This practice aimed to determine the absorbed dose to water, through the primary calibration method called dosimetry Fricke, which consists of ferrous ions (Fe + 2) to ferric (Fe + 3), generated by water radiolysis products which is the structural change of water molecule caused by ionizing radiation. A spectrophotometer was used to extract data for analysis at a wavelength (λ) 304 and 224 nm with function of measuring the absorbance using bottles with irradiated and nonirradiated Fricke solution. (author)

  2. Thermoluminescent dosimetry in dentistry students in radiological training; Dosimetria termo-luminiscente en estudiantes de odontologia en entrenamiento radiologico

    Energy Technology Data Exchange (ETDEWEB)

    Loya, M.; Duarte, R. [Escuela de Odontologia, Universidad Autonoma de Chihuahua (Mexico); Montero, M.E. [CIMAV, Chihuahua (Mexico); Gonzalez, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Ojeda, S.L.; Sanin, L.H. [Facultad de Enfermeria y Nutriologia, Chihuahua (Mexico)

    2007-07-01

    Full text: In this work, the obtained results of the mensuration of the equivalent one are presented of dose (E), in students of the career of Dentistry who during their training in radiology complete the three lists of patient, odontologist and observer. The study one carries out with 35 students (Odontologists), 7 men and 28 women, with ages between 20 and 24 years. A characterization of risk was made following the methodology of the Agency for the environmental control of United States (EPA), counting the number of shots in each list, during the time of training. The effective energy of the X rays used was of 24 KeV. The irradiation technique understood two modalities; the first one with 3 shots of 1.25 seconds and the second with 5 shots of 0.6 seconds. The measurement of E, was carried out with thermoluminescent dosemeters (TL) of LiF:Mg,Cu,P+PTFE, developed in the National Institute of Nuclear Research (ININ). The homogenization of the dosemeters showed a variation in its response to the radiation of 1.85%DS. For the odontologist position, the dosemeters was placed to the height of the chest and the measurement was multiplied by the number of shots that it was 304. The E value was of 3.62 mSv/four-month (11 mSv/year), without any safety equipment and of 2.02 mSv/four-month (6.14 mSv/year), when was considered the scenario for this position with use of vest and lead collar, like safety equipment, diminishing E, almost 50%. In the case of the corresponding position to patient, E, it was measured in different organs of interest, the obtained results are compared with the international standards. Recommendations are given for similar cases. (Author)

  3. Dose measurements in dental radiology using thermoluminescent dosimetry;Medicoes de dose em radiodiagnostico odontologico utilizando dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Chiara, Ana Claudia M. de; Costa, Alessandro M. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras; Pardini, Luiz Carlos [Universidade de Sao Paulo (FORP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Odontologia

    2009-07-01

    The aim of this work was the implementation of a code of practice for dosimetry in dental radiology using the technique of thermoluminescent dosimetry. General principles for the use of thermoluminescent dosimeters were followed. The irradiations were performed using ten X-ray equipment for intra-oral radiography and an X-ray equipment for panoramic radiography. The incident air kerma was evaluated for five different exposure times used in clinical practice for intra-oral radiographs. Using a backscatter factor of 1.2, it was observed that approximately 40% of the entrance skin dose values found for intra-oral radiographs are above the diagnostic reference level recommended in national regulation. Different configurations of voltage and current were used representing the exposure as a child, woman and man for panoramic radiographs. The results obtained for the air kerma area product were respectively 53.3 +- 5.2 mGy.cm{sup 2}, 101.5 +- 9.5 mGy.cm{sup 2} and 116.8 +- 10.4 mGy.cm{sup 2}. The use of thermoluminescent dosimetry requires several procedures before a result is recorded. The use of dosimeters with ionization chambers or semiconductors provides a simple and robust method for routine measurements. However, the use of thermoluminescent dosimetry can be of great value to large-scale surveys to establish diagnostic reference levels. (author)

  4. Dosimetry computer module of the gamma irradiator of ININ; Modulo informatico de dosimetria del irradiador gamma del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Ledezma F, L. E.; Baldomero J, R. [ININ, Gerencia de Sistemas Informaticos, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Agis E, K. A., E-mail: luis.ledezma@inin.gob.mx [Universidad Autonoma del Estado de Mexico, Facultad de Ingenieria, Cerro de Coatepec s/n, Ciudad Universitaria, 50100 Toluca, Estado de Mexico (Mexico)

    2012-10-15

    This work present the technical specifications for the upgrade of the dosimetry module of the computer system of the gamma irradiator of the Instituto Nacional de Investigaciones Nucleares (ININ) whose result allows the integration and consultation of information in industrial dosimetry subject under an outline client-server. (Author)

  5. Biological Dosimetry of X-rays by micronuclei study; Dosimetria Biologica de rayos-X mediante el estudio de micronucleos

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, E.; Silva, A.; Navlet, J.

    1991-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes citokinetics blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree centigree has been produced. Experimental data is fitted to model Y=C+ {alpha}D+BD''2 where Y is the number of micronuclei per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 24 refs.

  6. Biological Dosimetry of X-rays by micronuclei study; Dosimetria Biologica de rayos-X mediante el estudio de micronucleos

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, E; Silva, A; Navlet, J

    1991-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes citokinetics blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree centigree has been produced. Experimental data is fitted to model Y=C+ {alpha}D+BD''2 where Y is the number of micronuclei per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 24 refs.

  7. Differences between cross-section libraries for neutron dosimetry; Diferencas entre bibliotecas de secoes de choque para dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Tardelli, T.C.; Stecher, L.C.; Coelho, T.S.; Castro, V.A. De; Cavalieri, T.A.; Menzel, F.; Giarola, R.S.; Domingos, D.B.; Yoriyaz, H., E-mail: tiago.tardelli@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Engenharia Nuclear

    2013-08-15

    Absorbed dose calculations depend on a consistent set of nuclear data used in simulations in computer codes. Nuclear data are stored in libraries, however, the information available about the differences in dose caused by different libraries are rare. The libraries are processed by a computer system to be able to be used by a radiation transport code. One of the systems capable of processing nuclear data is the NJOY system. The objective of this study is to evaluate the nuclear data libraries for neutrons available in the literature, and to quantify the differences in absorbed dose obtained using the libraries JENDL 4.0, JEFF 3.3.1 and ENDF/B.VII. The absorbed dose calculation was performed on a simple geometric model, as spheres, and in anthropomorphic model of the human body based on the ICRP-110 for neutron transport simulation using the MCNP5 code. The results were compared with literature data. The results obtained with cross sections from the libraries JEFF and ENDF/B.VII have shown to be identical in most cases, except for one case where the difference has exceeded 10%. The results obtained with JENDL library has shown to be considerably different in most cases comparing to other two libraries. Some differences were over 200%. The dose calculations showed differences between the libraries, which is justified by differences in the cross sections. It has been observed that the cross sections values of certain nuclides assume quite different values in different libraries. These differences in turn cause considerable differences in dose calculations. (author)

  8. Application of numerical analysis methods to thermoluminescence dosimetry; Aplicacion de metodos de analisis numerico a la dosimetria por termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Ros, J M; Delgado, A

    1989-07-01

    This report presents the application of numerical methods to thermoluminescence dosimetry (TLD), showing the advantages obtained over conventional evaluation systems. Different configurations of the analysis method are presented to operate in specific dosimetric applications of TLD, such as environmental monitoring and mailed dosimetry systems for quality assurance in radiotherapy facilities. (Author) 10 refs.

  9. Thermoluminescent dosimetry in the radiodiagnostic area of the INNSZ; Dosimetria termoluminiscente en el area de radiodiagnostico del INNSZ

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, J.C.; Azorin N, J.; Rivera M, T. [Universidad Autonoma Metropolitana-Iztapalapa, 09340 Mexico D.F. (Mexico)

    1998-12-31

    During the year 1997 the Secretaria de Salud through the Direccion de Riesgos Radiologicos published the Mexican Official Standard about the medical diagnostic using X-rays in the Diario Oficial de la Federacion. They are of obligatory observance for all hospitals and radiological rooms which have medical diagnostic with X-ray equipment in the country. These standards were emitted with the purpose improve the conditions as for safety and radiological protection it is referred employing this type of ionizing radiation emitter equipment. Also it is presented the evaluation results about conditions existing about in thirteen X-ray medical diagnostic rooms in the Instituto Nacional de la Nutricion with the purpose of providing the radiological protection means toward the occupationally exposure personnel. It was realized measurements of each one of the blinding barriers for the X-ray equipment and it was suggested the appointments arrangement. (Author)

  10. Use of the calorimeter in the dosimetry for electron accelerators; Uso del calorimetro en la dosimetria para aceleradores de electrones

    Energy Technology Data Exchange (ETDEWEB)

    Chavez B, A

    1991-02-15

    The measure of different radiation types, with specific dosemeters, requires that the absorbed dose should be measured with accuracy by some common standard. The existent problem around the dosimetry of accelerated electrons has forced to the development of diverse detector types that after having analyzed the characteristics; dependability and reproducibility are used as dosemeters. Recently the calorimeters have been developed, with the purpose of carrying out dosimetry for electron accelerators. The RISO laboratory in Denmark, in it 10 MeV accelerator had been used for the dosimetry those water calorimeters, later on, using the principle of the water calorimeter, it was designing one similar, for the accelerator of 400 keV. Recently manufactured simple calorimeters of graphite have been used, which can be used in both accelerators of 10 MeV and 400 keV. (Author)

  11. Accreditation ISO/IEC 1705 in dosimetry: Experience and results; Acreditacion ISO/IEC 17025 en dosimetria: Experiencia y resultados

    Energy Technology Data Exchange (ETDEWEB)

    Martin Garcia, R.; Navarro Bravo, T.

    2013-07-01

    The objective of this work is to present the experience in the process of accreditation of the radiation dosimetry service in which there are trials for the determination of radiation doses due to internal and external exhibitions. Is They describe the aspects that were considered for the design and development of a system of quality and results after its implementation. A review of the benefits accreditation has been reported to the organization is finally made. (Author)

  12. Dosimetry of professionals involved in radio guided surgery; Dosimetria de los profesionales involucrados en la cirugia radioguiada

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, A. C.; Cardoso, G.; Ferreira, L. S.; Santos, A. I.

    2013-07-01

    The procedure of sentinel node localization is important because it allows less invasive staging of breast cancer. With the capture probe after intradermal injection of the radiopharmaceutical, the surgeon can identify the location of the sentinel node. The use of radioactive materials, generated considerable concern in terms of radiation exposure. The main objective is to evaluate the possible individual dose of each professional involved in the process of radio-location. (Author)

  13. A new implementation of multichannel radiochromic film dosimetry; Una nueva implementacion del analisis multicanal para la dosimetria mediante peliculas radiocromicas

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, C.; Martin Martin, G.; Bermudez Luna, R.; Lopez Fernandez, A.; Tores Olombrada, M. V. de

    2014-07-01

    The aims of this paper are to carry out a new implementation of the multichannel radiochromic film dosimetry (Micke A, Lewis D, Yu X. Multichannel film dosimetry with nonuniformity correction. Med Phys 2011;38:2523-34), to quantify the variation in gamma index as compared to the single channel film dosimetry, and to determine if the procedure achieves similar results by means of a different scanner that the one used by Micke et al. Radiochromic EBT2 films and a Microtek 9000 XL scanner were used. Our procedure simplifies the system calibration splitting it into two factors, manufactured batch and digitalization specific. Absorbed dose spatial distributions from an open radiotherapy beam without any modulation and 20 IMRT treatments were determined. Their gamma index maps were calculated and a comparison of the results from single channel and multichannel dosimetry was performed. A 5% mean increase in concordance was obtained by using the multichannel film dosimetry. Our results are similar to those reported by Micke et al. even though we are using a different scanner. (Author)

  14. Radiation chemical dosimetry by means of nitrate-nitrite; Dosimetria quimica de la radiacion aplicacion del sistema nitrato-nitrito

    Energy Technology Data Exchange (ETDEWEB)

    Tormo Ferrero, M J

    1977-07-01

    The different chemical systems used in dosimetry and the selection criteria for them are described. The general topics in dosimetry with alkali nitrates as well as the phenomena occurring in their radiolysis are also treated. The possibility of application in dosimetric areas useful in radiosterilization and industrial processes is studied too. (Author) 22 refs.

  15. A definitive method for dosimetry with radiochromic movie; Un metodo definitivo para la dosimetria con pelicula radiocromica

    Energy Technology Data Exchange (ETDEWEB)

    Miras del Rio, H.; Arrans Lara, R.

    2013-07-01

    Despite the undoubted benefits of radiochromic film as a two-dimensional radiation detector, the manufacturing process and characteristics of scanners make to present some inherent difficulties that result that its use is complex, tedious, and if not performed so appropriate, imprecise. A protocol that simplifies the calibration process while reducing the number of films used for this purpose is proposed systematically corrects several difficulties, both inherent in the manufacture of the film as the reader and, what is more important achieves levels comparable to those of other more widespread use detectors accuracy. (Author)

  16. Study of dosimetry CT in Skull for pediatric patients; Estudio de dosimetria TC en craneo para pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Ramos Amores, D.; Serna Berna, A.; Mata Colodro, F.; Puchades Puchades, V.

    2013-07-01

    The dose that receiving the patients in CT studies is the highest that can be received in a study of Radiology. If patients are children and we do studies with the same parameters as adults, they will receive a higher dose of radiation. This work seeks to expose the result of a dosimetric study on CT for children aged 0-15, carried out at the Hospital General Universitario de Santa Lucia in Cartagena during the year 2012. (Author)

  17. EPR dosimetry in tooth enamel by x radiation; Dosimetria EPR en esmalte dental irradiado con rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Dubner, Diana; Perez, Maria del Rosario; Gisone, P. [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina)] E-mail: ddubner@cae.arn.gov.ar; Fainstein, C.; Winkler, E. [Comision Nacional de Energia Atomica (CNEA), San Carlos de Bariloche (Argentina). Centro Atomico Bariloche]|[Universidad Nacional de Cuyo, Mendoza (Argentina). Inst. Balseiro; Saravi, Margarita [Comision Nacional de Energia Atomica (CNEA) (Argentina). Centro Atomico Ezeiza; Davila, Francisco [Ateneo Argentino de Odontologia, Buenos Aires (Argentina)

    2001-07-01

    Tooth enamel, extracted from molars, was irradiated with 66 keV X-rays, with doses up to 1 Gy. The preparation of the powder samples is described, as well as the protocol for the acquisition and processing of the spectra. The radiation induced paramagnetism is measured, at room temperature, by ESR spectroscopy. The ESR spectra is well described considering two paramagnetic species, with magnetic moments (in units of Bohr magnetrons) g=2,0041, and g1=2,0018, g2=1,9972. The ESR data (peak-to-peak amplitude per mg, hpp/mg, vs dose D), for doses 0 Gy

  18. Dosimetria “in vivo” para implantes ginecologicos de cancer de cervix, con braquiterapia de alta tasa de dosis (hdrb

    OpenAIRE

    Guillen G., Oscar O.; Duran S., Rosalia

    2009-01-01

    SOLCA Guayaquil en el Servicio de Braquiterapia dispone de un equipo de carga diferida de alta tasa de dosis, Microselectron HDR de la Empresa Nucletron, equipado con una fuente de Ir192, para la realización de tratamiento a pacientes portadores de cáncer en diferentes localizaciones. Se usa un maniquí de sólido de PMMA tipo 9193, de la PTW con el objetivo de determinar la tasa de kerma en aire de la fuente de Ir192, cuyo error no supera el 0.5%. Adicionalmente, se establece un mecanismo ...

  19. Use of radiological evaluation system from the Instituto de Radioprotecao e Dosimetria in the analysis of recent radiation accidents

    International Nuclear Information System (INIS)

    Silva, Rodolfo Julio da

    2013-01-01

    The response to an emergency situation involving ionizing radiation requires the joint participation of professionals from various kind of knowledge, belonging to public and private organizations (in the local, state and federal levels). The theme radiation tends to be an additional challenging factor - considering that it's, usually, remembered for its macabre and ominous aspect, in spite of the benefits provided by it - which makes the implementation of actions to protect the public, emergency professionals, the environment and property, very difficult. To this, we can add the complicating factor that, in most cases, the technician (holder of basic or advanced on the subject) is far !Tom the place where this action unfolds. The accident/incident takes the form of a radioactive source (sometimes orphaned, one that gone astray or even stolen) that is found by a person unaware of the risks to which they are being exposed or, let not forget about it, the non-observance of safety standards in industries and workplaces, by their own operators. Thus, before integrating emergency response plans with conventional plans specific to the prompt response to radiological emergencies, it is necessary that some measures had been anticipated and that some actions had, already, been planned - with the intention of mitigate health, psychological and economical damage, in ali of kind. To do this, since in the course of the second decade of the second millennium, and since you own a portable personal computer (Note or Netbook), or even with a mobile device (cellular) with a bit more resources, both of them previously updated, a responder (or even a qualified technician that is next to that fact) may already guide, at least, about a safety distances !Tom the source. Since he had knowledge about some characteristics of the source (its individual data), he can plan ahead about the possible serious situation that unfolds itself and emergency responders will find, when it get to the site. With the situation assessments done, the formal emergency team triggered will can prepare itself (with personnel and technical-materials facilities) to resolve the incident in the shortest time and with the least possible risks. (author)

  20. Course of training in Specific internal dosimetry for the patient; Curso de capacitacion en dosimetria interna especifica para el paciente

    Energy Technology Data Exchange (ETDEWEB)

    Rojo, A.M.; Michelin, S.C. [Dosimetria Interna, Autoridad Regulatoria Nuclear, Av. Del Libertador 8250 CP (429BNP), Buenos Aires (Argentina); Gomez P, I.M. [Sociedad Argentina de Radioproteccion, Av. del Libertador 8250, Buenos Aires (Argentina)]. e-mail: arojo@cae.arn.gov.ar

    2006-07-01

    In this work the experience obtained in a course organized in Argentina to qualify professionals in the radiopharmaceutical dosimetry using the methodology MIRD and the patient's images is presented. The motivation to carry out it was based on the continuous development of new radiopharmaceuticals with therapeutic purposes that makes necessary the knowledge of the distribution of the absorbed dose to be able to establish the dose-response relationship. The main objective was the study of the biokinetic model and those techniques available that starting from images can contribute information of specific parameters of the patient to calculate with more accuracy the doses in the tumor and in different organs. In the design of the program of this course it was considered to approach the different focuses for the calculation of specific dose of the patient and includes the following topics: the patient's radiological protection, new concepts in damages by radiations (bystander effect), methodology for the internal dosimetry by radiopharmaceuticals, dosimetric systems (MIRD/ICRP), revision of the physical phantoms, design of kinetic studies, compartmental models, calculation tools and the demonstration of the programs SAAM and OLINDA; calculation of activity starting from the patient's images (planar and SPECT). Principles of the gamma camera: the dispersed radiation, calculation of the activity with planar images, the attenuation, correction of the dispersed radiation, collimation problems. SPECT: the common method of reconstruction, basic principles, method of filtered over head projection and iterative methods (MLEM/OSEM), measurement of the attenuation maps, problems of the penetration in the collimator (I-131, I-123), effects of partial volume, incorporation of corrections in an iterative reconstruction. Dosimetry in bone marrow, discussion of study cases of new radiopharmaceuticals. Internal dosimetry in small scale for electrons and photons. Perspectives of the Monte Carlo method in the internal dosimetry. Dose calculation with the LundAdose program of the 'Lund University'. The development of these theoretical practice activities including conferences of foreign experts and practices in reference centers of Argentina, took place in Buenos Aires in August, 2004 during one week on complete time. This was the mark for the conjunct work of professionals of different specialties (doctors, physical, biochemical) of the national and regional environment. The survey carried out at the end of this first course showed the interest for a continuity in the in agreement upgrade to the technological advances in this topic, what allows us to conclude that the formation of those involved professionals should be faced in the region countries in permanent form. (Author)

  1. Dosimetry in medical specialist in procedures of interventionist radiology; Dosimetria en medico especialista en procedimientos de radiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E. [Universidad Autonoma Metropolitana, Unidad Xochimilco, Calz. del Hueso 1100, Col. Villa Quietud, 04960 Mexico D. F. (Mexico); Vazquez V, J. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico); Izeta G, A. C. [Hospital Central Militar, Periferico y Av. Ejercito Nacional s/n, 11200 Mexico D. F. (Mexico); Azorin V, J. C. [Universidad de Guanajuato, Instituto de Fisica, Loma del Bosque 103, 37150 Leon, Guanajuato (Mexico); Arreola, M., E-mail: gaen1310@correo.xoc.uam.mx [Shands Hospital at University of Florida, Department of Radiology, PO Box 100374, Gainesville, FL 32610-0374 (United States)

    2014-08-15

    In this work are presented the experimental results of determining the dose in different body parts, measured by thermoluminescent dosimeters, to medical specialists of implantation procedures of definitive cardiac pacemaker. The medical personnel in ten intervention procedures were controlled according to the procedure type, pathological indication, fluoroscopy time and machine generating estimates of the patient doses. The doses to the extremities of the cardiologist were measured by means of thermoluminescent dosimeters (TLD). The domains of first level in the hand are in the index finger of the left and the right hand. The medium doses of the skin in the eyes, a report of the dose received during each type of intervention procedure in the glandular thyroid and fingers of the cardiologists is made. The results represent the integrated dose to the cardiologist, received during the implantation procedures of definitive cardiac pacemaker in the same patient. By a half time of detection of 70 minutes for patient, the half dose of the skin, received for the right and left hand, ascended to 1,4 mSv, under the glove. In conclusion, the dose average for the dosimeters of the thyroid gland and forehead was varied from 0,41 up to 1,14 mSv for study. The exposure to the X-rays is a topic to consider, more important every time on the development of systematic procedures little invasive, including the angiography, catheter, worker and patient. (Author)

  2. Tl dosimetry around equipment s for dental radiography; Dosimetria TLD en torno a equipos para radiografia dental

    Energy Technology Data Exchange (ETDEWEB)

    Medrano, E.; Robles G, M. A. [Universidad Autonoma de Zacatecas, Unidad Academica de Odontologia, Apdo. Postal 336, 98000 Zacatecas (Mexico); Vega C, H. R.; Letechipia de L, C.; Hernandez D, V. M., E-mail: edumeco@yahoo.com.mx [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-08-15

    The ambient dose equivalent around X-rays units used in dentistry has been measured. The radiation that escapes of the tail stock of the X-rays equipment was also measured, and the dose in the surfaces of a polyethylene spherical mannequin and other of water, used to represent the patient and the operator, respectively. The study was realized with thermoluminescent dosimeters of the type 100. The operation conditions of the X-rays units were varied when the ambient dose equivalent was measured. In the other measurements the equipment s were operated to 70 k Vp and 8 m A. In the ambient dose equivalent was found asymmetry, likewise the due dose to the radiation that escapes of one of tail stocks was also asymmetric. The dose values in the mannequins went minors to the recommended reference values. (Author)

  3. Estimations of internal dosimetry: practical calculations of incorporated activity; Estimaciones de dosimetria interna: calculos practicos de actividad incorporada

    Energy Technology Data Exchange (ETDEWEB)

    Cortes C, A. [CNSNS, Dr. Barragan 779, 03020 Mexico D.F. (Mexico)

    2003-07-01

    The National Commission of Nuclear Security and Safeguards (CNSNS) carries out periodically measurements of corporal activity to Occupationally Exposed Personnel (POE) to determine that the received doses are in according to that settled down in the General Regulation of Radiological Security. In this work the results of the incorporated activity estimates starting from the results of the measurements that were carried out in the one CNSNS laboratory are presented, with which it should be determine lastly the internal dose. Its were used different methodologies to estimate the incorporated activity: estimate with isolated data, estimate with global data and method of the best estimate, demonstrating this last to be the more appropriate to determine the internal dose. (Author)

  4. A new method for dosimetry with films radiochromic; Un nuevo metodo para la dosimetria con peliculas radiocromica

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Carot, I.

    2013-07-01

    in this paper a new method is presented and the results of the comparison between the calibration is summarized based on a planning reference and calibration obtained from the irradiated fragments measure different dose levels multichannel compare dosimetry based on the weighted average dosimetry described by Micke et al.(present in the FilmQAPro software) and, finally, show different results obtained with the method proposed in several applications clinics. (Author)

  5. Neutron dosimetry. Environmental monitoring in a BWR type reactor; Dosimetria de neutrones. Monitoreo ambiental en un reactor del tipo BWR

    Energy Technology Data Exchange (ETDEWEB)

    Tavera D, L; Camacho L, M E

    1991-01-15

    The measurements carried out on reactor dosimetry are applied mainly to the study on the effects of the radiation in 108 materials of the reactor; little is on the environmental dosimetry outside of the primary container of BWR reactors. In this work the application of a neutron spectrometer formed by plastic detectors of nuclear traces manufactured in the ININ, for the environmental monitoring in penetrations around the primary container of the unit I of the Laguna Verde central is presented. The neutron monitoring carries out with purposes of radiological protection, during the operational tests of the reactor. (Author)

  6. Dosimetry on the radiological risks prevention in radiotherapy; La dosimetria en la prevencion de riesgos radiologicos en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Fornet R, O. M.; Perez G, F., E-mail: nuclear2@citmahlg.holguin.inf.cu [Delegacion Territorial del CITMA, Peralta 16 esq. P. Feria, Rpto. Peralta, 80400 Holguin (Cuba)

    2014-08-15

    Dosimetry in its various forms plays a determining role on the radiological risks prevention in radiotherapy. To prove this in this paper is shown an analysis based on the risk matrix method, how the dosimetry can influence in each stages of a radiotherapy service; installation and acceptance, operation, maintenance and calibration. For each one of these stages the role that can play is analyzed as either the initiating event of a radiological accident or limiting barrier of these events of the dosimetric processes used for the individual dosimetry, the area monitoring, fixed or portable, for radiation beam dosimetry and of the patients for a radiotherapy service with cobalt-therapy equipment. The result of the study shows that the application of a prospective approach in the role evaluation of dosimetry in the prevention and mitigation of the consequences of a radiological accident in radiotherapy is crucial and should be subject to permanent evaluation at each development stage of these services. (author)

  7. Statistical analysis of personal dosimetry of exposed workers; Analisis estadistico de la dosimetria personal de trabajadores expuestos

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Munoz, F. J.; Alejo Luque, L.; Mas Munoz, I.; Serrada Hierro, A.

    2013-07-01

    The dosimetry centers accredited by the Nuclear Safety Council (CSN) normally report overcoming legal limits, or some fraction thereof, but do not provide comparative dosimetric criteria indicating if assigned to a given dose is large TPE or small relative to that of their peers. In order to help to resolve the difficulties mentioned ds, it has developed an application that statistically processes the dosimetric data provided by the National Dosimetry Center. (Author)

  8. Thermoluminescent dosimetry in the radiodiagnostic area of the INNSZ; Dosimetria termoluminiscente en el area de radiodiagnostico del INNSZ

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, J C; Azorin N, J; Rivera M, T [Universidad Autonoma Metropolitana-Iztapalapa, 09340 Mexico D.F. (Mexico)

    1999-12-31

    During the year 1997 the Secretaria de Salud through the Direccion de Riesgos Radiologicos published the Mexican Official Standard about the medical diagnostic using X-rays in the Diario Oficial de la Federacion. They are of obligatory observance for all hospitals and radiological rooms which have medical diagnostic with X-ray equipment in the country. These standards were emitted with the purpose improve the conditions as for safety and radiological protection it is referred employing this type of ionizing radiation emitter equipment. Also it is presented the evaluation results about conditions existing about in thirteen X-ray medical diagnostic rooms in the Instituto Nacional de la Nutricion with the purpose of providing the radiological protection means toward the occupationally exposure personnel. It was realized measurements of each one of the blinding barriers for the X-ray equipment and it was suggested the appointments arrangement. (Author)

  9. A single-aliquot OSL protocol using bracketing regenerative doses to accurately determine equivalent doses in quartz

    International Nuclear Information System (INIS)

    Folz, Elise; Mercier, Norbert

    1999-01-01

    In most cases, sediments show inherent heterogeneity in their luminescence behaviours and bleaching histories, and identical aliquots are not available: single-aliquot determination of the equivalent dose (ED) is then the approach of choice and the advantages of using regenerative protocols are outlined. Experiments on five laboratory bleached and dosed quartz samples, following the protocol described by Murray and Roberts (1998. Measurement of the equivalent dose in quartz using a regenerative-dose single aliquot protocol. Radiation Measurements 27, 171-184), showed the hazards of using a single regeneration dose: a 10% variation in the regenerative dose yielded some equivalent dose estimates that differed from the expected value by more than 5%. A protocol is proposed that allows the use of different regenerative doses to bracket the estimated equivalent dose. The measured ED is found to be in excellent agreement with the known value when the main regeneration dose is within 10% of the true equivalent dose

  10. Photon energy readings in OSL dosimeter filters: an application to retrospective dose estimation for nuclear medicine workers.

    Science.gov (United States)

    Villoing, Daphnée; Kitahara, Cari M; Passmore, Christopher; Simon, Steven L; Yoder, R Craig

    2018-06-19

    This work investigates the applicability of using data from personal monitoring dosimeters to assess photon energies to which medical workers were exposed. Such determinations would be important for retrospective assessments of organ doses to be used in occupational radiation epidemiology studies, particularly in the absence of work history or other information regarding the energy of the radiation source. Monthly personal dose equivalents and filter ratios under two different metallic filters contained in the Luxel+® dosimeter were collected from Landauer, Inc. from 19 nuclear medicine (NM) technologists employed by three medical institutions, the institution A only performing traditional NM imaging (primarily using 99mTc) and institutions B and C also performing positron emission tomography (PET, using 18F). Calibration data of the Luxel+® dosimeter for various X-ray spectra were used to establish ranges of filter ratios from 1.1 to 1.6 for 99mTc and below 1.1 for 18F. Median filter ratios were 1.33 (Interquartile range (IQR), 0.15) for institution A, 1.08 (IQR, 0.16) for institution B, and 1.08 (IQR, 0.14) for institution C. The distributions of these filter ratios were statistically-significantly different between the institution A only performing traditional NM imaging and institutions B and C also performing PET imaging. In this proof-of-concept study, filter ratios from personal dosimeters were used to assess differences in photon energies to which NM technologists were exposed. Dosimeters from technologists only performing traditional NM procedures mostly showed Al/Cu filter ratios above 1.2, those likely performing only PET in a particular month had filter ratios below 1.1, and those which showed filter ratios between 1.1 and 1.2 likely came from technologists rotating between traditional NM and PET imaging in the same month. These results suggest that it is possible to distinguish technologists who only worked with higher-energy procedures versus those who only worked with other types of NM procedures. © 2018 IOP Publishing Ltd.

  11. Testing the use of OSL from quartz grains for dating debris flows in Miyun, northeast Beijing, China

    DEFF Research Database (Denmark)

    Zhao, Qiuyue; Thomsen, Kristina Jørkov; Murray, Andrew

    2015-01-01

    Extreme seasonal summer rain storms are common in the mountains to the north east of Beijing and these often result in mass movement of sediment slurries transported for up to a few km. These debris flows can be deadly and are very destructive to infrastructure and agriculture. This project tests...... the application of luminescence dating to determining the return frequency of such extreme events. The high sediment concentration and the very short flow duration gives very little opportunity for daylight resetting during transport and only a small fraction of the total mass is likely to be reset before...

  12. A single-aliquot OSL protocol using bracketing regenerative doses to accurately determine equivalent doses in quartz

    CERN Document Server

    Folz, E

    1999-01-01

    In most cases, sediments show inherent heterogeneity in their luminescence behaviours and bleaching histories, and identical aliquots are not available: single-aliquot determination of the equivalent dose (ED) is then the approach of choice and the advantages of using regenerative protocols are outlined. Experiments on five laboratory bleached and dosed quartz samples, following the protocol described by Murray and Roberts (1998. Measurement of the equivalent dose in quartz using a regenerative-dose single aliquot protocol. Radiation Measurements 27, 171-184), showed the hazards of using a single regeneration dose: a 10% variation in the regenerative dose yielded some equivalent dose estimates that differed from the expected value by more than 5%. A protocol is proposed that allows the use of different regenerative doses to bracket the estimated equivalent dose. The measured ED is found to be in excellent agreement with the known value when the main regeneration dose is within 10% of the true equivalent dose.

  13. Using the OSL single-aliquot regenerative-dose protocol with quartz extracted from building materials in retrospective dosimetry

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Solongo, S.; Murray, A.S.

    2000-01-01

    We report on the application of the single-aliquot regenerative-dose (SAR) protocol to the optically stimulated luminescence signal from quartz extracted from fired bricks acid unfired mortar in retrospective dosimetry. The samples came from a radioactive materials storage facility, with ambient...... dose rates of about 0.1 mGy/h. A detailed dose-depth profile was analysed from one brick, and compared with dose records from area TL dosemeters. Small-aliquot dose-distributions were analysed from the mortar samples; one associated with the exposed brick, and one from a remote site exposed only...

  14. Using the OSL single-aliquot regenerative-dose protocol with quartz extracted from building materials in retrospective dosimetry

    International Nuclear Information System (INIS)

    Boetter-Jensen, L.; Solongo, S.; Murray, A.S.; Banerjee, D.; Jungner, H.

    2000-01-01

    We report on the application of the single-aliquot regenerative-dose (SAR) protocol to the optically stimulated luminescence signal from quartz extracted from fired bricks and unfired mortar in retrospective dosimetry. The samples came from a radioactive materials storage facility, with ambient dose rates of about 0.1 mGy/h. A detailed dose-depth profile was analysed from one brick, and compared with dose records from area TL dosemeters. Small-aliquot dose-distributions were analysed from the mortar samples; one associated with the exposed brick, and one from a remote site exposed only to background radiation. We conclude that unfired materials have considerable potential in retrospective dosimetry

  15. The Temporal-Spatial Distribution of Shule River Alluvial Fan Units in China Based on SAR Data and OSL Dating

    Directory of Open Access Journals (Sweden)

    Lu Zhang

    2013-12-01

    Full Text Available Alluvial fans in arid and semi-arid regions can provide important evidence of geomorphic and climatic changes, which reveal the evolution of the regional tectonic activity and environment. Synthetic aperture radar (SAR remote sensing technology, which is sensitive to geomorphic features, plays an important role in quickly mapping alluvial fan units of different ages. In this paper, RADARSAT-2 (Canada’s C-band new-generation radar satellite and ALOS-PALSAR (Japan’s advanced land observing satellite, phased array type L-band SAR sensor data, acquired over the Shule River Alluvial Fan (SRAF, are used to extract backscattering coefficients, scattering mechanism-related information, and polarimetric characteristic parameters. The correlation between these SAR characteristic parameters and fan units of the SRAF of different ages was studied, and the spatial distribution of fan units, since the Late Pleistocene, was extracted based on the Maximum Likelihood classification method. The results prove that (1 some C-band SAR parameters can describe the geomorphic characteristics of alluvial fan units of different ages in the SRAF; (2 SAR data can be used to map the SRAF’s surface between the Late Pleistocene and the Holocene and to extract the spatial distribution of fan units; and (3 the time-spatial distribution of the SRAF can provide valuable information for tectonic and paleoenvironmental research of the study area.

  16. OSL and Tl response characterization of micro LiF:Mg, Ti dosimeters to be applied to VMAT quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, A.; Campos, L. L. [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Sakuraba, R. K.; Da Cruz, J. C., E-mail: ambravim@hotmail.com [Sociedade Beneficente Israelita Brasileira - Hospital Albert Einstein, Av. Albert Einstein 627/701, Jardim Leonor, 05652-900 Sao Paulo (Brazil)

    2014-08-15

    VMAT Rapid Arc is a new method of treatment responsible for a change in the setting of radiotherapy, bringing benefits and allowing a lower toxicity in the treatment of patients. With this treatment is possible to minimize the radiation dose to the healthy tissues and escalate the dose to the target volume (tumor) (Hall, 1998; Mundt, 2005; Bortfeld, 2006). The quality assurance is essential to verify the operation of all components involved in the process of treatment planning and dose delivery. Several organizations recommended the verification of patient dose for quality improvement in radiotherapy and the recommended maximum values for the uncertainty in the dose range of ± 5% (ICRU, 1976, AAPM, 1983). This paper aims to evaluate the feasibility of applying LiF:Mg,Ti micro dosimeters as a new method of dosimetry to VMAT Rapid Arc. (Author)

  17. Formulation, radiopharmaceutical kinetics and dosimetry of the {sup 188}Re(V)-DMSA complex; Formulacion, radiofarmacocinetica y dosimetria del complejo {sup 188}Re(V)-DMSA

    Energy Technology Data Exchange (ETDEWEB)

    Garcia S, L; Ferro F, G [Departamento de Materiales Radiactivos. Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Salazar, Estado de Mexico (Mexico); Murphy, C.A. de; Pedraza L, M [Departamento de Medicina Nuclear, Instituto Nacional de la Nutricion, Salvador Zubiran, Mexico D.F. (Mexico); Azorin N, J [Departamento de Fisica, Universidad Autonoma Metropolitana Iztapalapa, Mexico D.F. (Mexico)

    1999-07-01

    It was developed through experimental design (ANOVA), a formulation to prepare the {sup 188} Re(V)-Dmsa complex. Likewise, there were realized studies of radiopharmaceutical kinetics and internal dosimetry in animals, its normal and with induced tumors, considering an open bi compartmental model using the MIRD methodology. The {sup 188} Re(V)-Dmsa complex was obtained with a radiochemical purity greater than 95% incubating 30 min at 90 Centigrade under the following formulation: [SnCl{sub 2}] = 1.4 mg/ml, [ascorbic acid] = 0.5 mg/ml, p H = 2.0 - 3.0. The stability test of the formulation, shows that after 48 h of its preparation, does not produce radiolytic degradation neither chemical decomposition. The radiopharmaceutical kinetics data show an average residence time 7.2h, velocity constant {alpha} = 0.6508h{sup -1} and {beta} = 0.1046 h{sup -1} with an apparent distribution volume 6.9 l. The main elimination via was renal and it was observed osseous caption with an accumulated activity 522.049 {+-} 62 MBq h (residence time 14.1094 {+-} 1.69h). In according with the dosimetric calculations, by each 37 MBq injected, the equivalent dose at the tumor was 9.67{+-} 0.33 Sv/g, for an effective dose 0.292 {+-} 0.0017 mSv/MBq. The images obtained in the gamma camera of the mice with induced tumors, show that do not have significant accumulation in the metabolic organs. The caption in bone and in tumors induced of the {sup 188} Re(V)-Dmsa complex, show its potential for be used as a palliative agent for pain in patients with osseous metastasis and in the treatment of tumors of soft tissue. (Author)

  18. Personal dosimetry calculations by means of radio pharmacokinetic and gamma graphic studies; Calculos de dosimetria personalizada por medio de estudios radiofarmacocineticos y gammagraficos

    Energy Technology Data Exchange (ETDEWEB)

    Arteaga de Murphy, C; Ferro F, G; Pedraza L, M; Montoya M, C E [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion, Vasco de Quiroga 15, 14000 Mexico D.F. (Mexico)

    2000-07-01

    The determination of the absorbed radiation dose is an essential factor to assess the risk to patient with a diagnostic study of nuclear medicine but over all it is indispensable for predicting the efficiency of individualized radio pharmacotherapy and weighting up the risk/benefit of the treatment. In studies for diagnostic or/and treatment of nuclear medicine generally the absorbed radiation dose is not determined for each patient since the methods for estimating it are laborious and include complex models such biological as mathematical, therefore is very important to have a relatively easy method. The obtained data with {sup 99m} Tc-Abp., a new radiopharmaceutical for osseous gammagraphy, were used with the purpose of exemplifying a practical method. The radio pharmacokinetic parameters were determined during 24 hours in 10 health voluntaries and serial gamma grams were taken during two hours to another voluntaries. The obtained data were used to estimate, with the MIRDOSE3 computer program, the absorbed radiation dose in an osseous dragging with {sup 99m} Tc-Abp. is low: 0.00472 m Gy/MBq to osseous marrow, mainly to the vertebral column and femur, and 0.00169 m Gy/ MBq to whole body. These data are lower than those informed in the medical literature for other bis phosphonates. (Author)

  19. Thermoluminescent dosemeters characterization for patient dosimetry in diagnostic radiology preliminary results;Caracterizacao de dosimetros termoluminescentes para dosimetria de pacientes em radiodiagnostico - resultados iniciais

    Energy Technology Data Exchange (ETDEWEB)

    Castro, William J.; Squair, Peterson L. [Faculdade Novo Rumo, Belo Horizonte, MG (Brazil); Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Gonzaga, Natalia B. [Universidade Unincor, Belo Horizonte, MG (Brazil); Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Nogueira, Maria S.; Silva, Teogenes A. da [Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2009-07-01

    The determination of the metrological characteristics of thermoluminescent (TL) dosimeters plays an important role in dosimetry of patients submitted to x-ray examinations for diagnostic purpose. Entrance surface doses can be measured with TL dosimeters to verify the compliance with the diagnostic reference levels. Organ doses can be estimated through TL measurements in an anthropomorphic phantom which it allows the radiation risk assessment. In this work, LiF:Mg,Ti (TLD-100) rod and chip thermoluminescent dosimeters were characterized considering their use for patient dosimetry in computerized tomography and mammography. Preliminary results showed that TL dosimeters have a response reproducibility of 7.8% and 4.8% and homogeneity of 18.4% and 6.5% for rod and chip shapes, respectively. (author)

  20. Progetto EURAMET: HLT03 DUTy - Dosimetria per terapie ultrasonore. Confronto tra metodi di misura - EURAMET: HLT03 DUTy - Dosimetry for ultrasound therapy. Intercomparison of methods

    Directory of Open Access Journals (Sweden)

    Giovanni Durando

    2016-03-01

    Full Text Available La mancanza di una definizione della dose ultrasonora rende di fatto impossibile la valutazione della più appropriata “quantità” energia ceduta ai tessuti dal fascio ultrasonoro emesso da un trasduttore durante una terapia. Il progetto di ricerca “Dosimetry for Ultrasound Therapy - DUTy”, finanziato dal programma di ricerca EURAMET EMRP, aveva tra i suoi principali obiettivi, oltre al confronto interlaboratorio che validasse le capacità metrologiche dei laboratori partecipanti, la ricerca della definizione di dose ultrasonora che consentisse la definizione di un piano terapeutico specifico per ogni paziente. ------ Standardized and traceable dose has not yet been developed for medical ultrasound applications. This means that the ‘amount’ of ultrasound required for a particular therapy cannot be calculated and that the ‘amount’ actually delivered quantified. The aim of EURAMET EMRP project “Dosimetry for Ultrasound Therapy - DUTy” project was developing the metrological infrastructure (definitions, validated measurement and modelling methods which underpins the specification of dose for therapeutic ultrasound applications allowing appropriate treatment planning and risk assessment.

  1. Development and application of a pediatric head phantom for dosimetry in computed tomography; Desenvolvimento e aplicacao de um simulador pediatrico craniano para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Elaine Wirney

    2016-11-01

    To determine the exposure levels and the absorbed dose in patients undergoing CT scans, is necessary to calculate the CT dose index in measurements with a PMMA or water phantom. The phantom must be enough to simulate the attenuation and scattering characteristics of a human body or parts in a radiation field. The CT specific quantities : CT air kerma index (Ca,100) , weighted CT air kerma index (CW ), a total volume CT air kerma index (Cvol) and the CT air kerma-length product (PKL) must be determined and compared to literature reference levels. In this work a head pediatric phantom was developed, considering that the Brazilian published Diagnostic Reference Levels (DRL) are based on adult phantom measurements. This developed phantom shows a construction innovation using materials to simulate the skullcap, cortical bone (aluminum) and cancellous bone (PVC), and it was filled with distilled water. The phantom dimension follows the recommendations of the World Health Organization and the International Commission on Radiation Units for children from 0 to 5 years old head size: diameter of 160 mm and height of 155 mm. The skullcap has 4 mm of thickness and 111.9 mm of internal diameter. In order to evaluate its behavior, tests were carried out in calibration laboratories and in clinical beams. The results showed attenuation up to 23% when different materials are used as skullcap, demonstrating that the DRLs adopted could be overestimating the dose received by pediatric patients. It is observed that the dose received by CT skull scans presents different distribution, due to the skullcap partially attenuation and/or backscattering which is not considered when the PMMA phantom is used.

  2. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram; Dosimetria termoluminiscente In vivo en estudios de tomografia computada helicoidal y urograma excretor

    Energy Technology Data Exchange (ETDEWEB)

    Cruz C, D.; Azorin N, J. [UAM-I, 09340 Mexico D.F. (Mexico); Saucedo A, V.M.; Barajas O, J.L. [Unidad de Especialidades Medicas, Secretaria de la Defensa Nacional, 11500 Mexico D.F. (Mexico)

    2005-07-01

    The dosimetry is the field of measurement of the ionizing radiations. It final objective is to determine the 'absorbed dose' for people. The dosimetry is vital in the radiotherapy, the radiological protection and the treatment technologies by irradiation. Presently work, we develop 'In vivo' dosimetry, in exposed patients to studies of helical computed tomography and excretory urogram. The dosimetry 'in vivo' was carried out in 20 patients selected aleatorily, for each medical study. The absorbed dose was measured in points of interest located in crystalline, thyroid, chest and abdomen of each patient, by means of thermoluminescent dosemeters (TLD) LiF: Mg,Cu,P + Ptfe of national fabrication. Also it was quantified the dose in the working area. (Author)

  3. Characterization of chemical compounds for dosimetry of the radiation in industrial processes; Caracterizacao de compostos quimicos para dosimetria das radiacaoes em processos industriais

    Energy Technology Data Exchange (ETDEWEB)

    Galante, Ana Maria Sisti

    1999-07-01

    Different chemical compounds have been studied to optimize dosimetric systems in irradiation processes. In this study 2,3,5 Triphenyl -2H- Tetrazolium Chloride, Brilliant Cresyl Blue, Bromocresol Green and Potassium Nitrate were investigated for their merits or faults, for {sup 60} Co gamma field, in order to verify if can be considered as dosimeters. Fricke solution was used as reference dosimeter to determine absorption dose rates at the gamma facilities.Only Bromocresol Green and Potassium Nitrate are recommended for dosimetry purposes since the main characteristics were achieved. The other two compounds could be used in dosimetry with changes in their formulation. Bromocresol Green and potassium Nitrate are reproducible and radiation sensitive for absorbed doses from 300 Gy to 150 kGy Bromocresol Green was used in liquid form and Potassium Nitrate was prepared in solid pellets form. Spectrophotometry in the visible region was used as the main detection technique, which allows relating optical absorption, before and after irradiation, with the absorbed dose. The maximum absorption wavelength for each compound was observed at 450-460nm for bromocresol Green and 546nm for Potassium Nitrate. Dose calibration curves are linear for both compounds in all dose intervals. When irradiated with accelerated electrons, with energies between o,9 MeV and 1,5MeV, optical absorption intensification, of about 2,6 times, was observed when comparing results for Potassium Nitrate, with those for gamma rays. All the evaluations are presented in this work. (author)

  4. Training of reverse propagation neural networks applied to neutron dosimetry; Entrenamiento de redes neuronales de propagacion inversa aplicadas a la dosimetria de neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez P, C. F.; Martinez B, M. R.; Leon P, A. A.; Espinoza G, J. G.; Castaneda M, V. H.; Solis S, L. O.; Castaneda M, R.; Ortiz R, M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Av. Ramon Lopez Velarde 801, Col. Centro, 98000 Zacatecas, Zac. (Mexico); Mendez V, R. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Laboratorio de Patrones Neutronicos, Av. Complutense 22, 28040 Madrid (Spain); Gallego, E. [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, ETSI Industriales, Jose Gutierrez Abascal 2, 28006 Madrid (Spain); De Sousa L, M. A. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Pampulha, Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Neutron dosimetry is of great importance in radiation protection as aims to provide dosimetric quantities to assess the magnitude of detrimental health effects due to exposure of neutron radiation. To quantify detriment to health is necessary to evaluate the dose received by the occupationally exposed personnel using different detection systems called dosimeters, which have very dependent responses to the energy distribution of neutrons. The neutron detection is a much more complex problem than the detection of charged particles, since it does not carry an electric charge, does not cause direct ionization and has a greater penetration power giving the possibility of interacting with matter in a different way. Because of this, various neutron detection systems have been developed, among which the Bonner spheres spectrometric system stands out due to the advantages that possesses, such as a wide range of energy, high sensitivity and easy operation. However, once obtained the counting rates, the problem lies in the neutron spectrum deconvolution, necessary for the calculation of the doses, using different mathematical methods such as Monte Carlo, maximum entropy, iterative methods among others, which present various difficulties that have motivated the development of new technologies. Nowadays, methods based on artificial intelligence technologies are being used to perform neutron dosimetry, mainly using the theory of artificial neural networks. In these new methods the need for spectrum reconstruction can be eliminated for the calculation of the doses. In this work an artificial neural network or reverse propagation was trained for the calculation of 15 equivalent doses from the counting rates of the Bonner spheres spectrometric system using a set of 7 spheres, one of 2 spheres and two of a single sphere of different sizes, testing different error values until finding the most appropriate. The optimum network topology was obtained through the robust design methodology of artificial neural networks where the parameters of the network that produced the best results were selected. (Author)

  5. Uncertainty analysis in the determination of absorbed dose in water by Fricke chemical dosimetry; Analise das incertezas na determinacao da dose absorvida na agua por dosimetria quimica Fricke

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Fabia; Aguirre, Eder Aguirre, E-mail: fabiavasco@hotmail.com, E-mail: ederuni01@gmail.com [Fundacao do Cancer, Rio de Janeiro, RJ (Brazil); Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

    2016-07-01

    This work studies the calculations of uncertainties and the level of confidence that involves the process for obtaining the dose absorbed in water using the method of Fricke dosimetry, developed at Laboratorio de Ciencias Radiologicas (LCR). Measurements of absorbance of samples Fricke, irradiated and non-irradiated is going to use in order to calculate the respective sensitivity coefficients, along with the expressions of the calculation of Fricke dose and the absorbed dose in water. Those expressions are used for calculating the others sensitivity coefficients from the input variable. It is going to use the combined uncertainty and the expanded uncertainty, with a level of confidence of 95.45%, in order to report the uncertainties of the measurement. (author)

  6. A new computation tool for neutron spectrometry and dosimetry; Una nueva herramiento de computo para la espectrometria y dosimetria de neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Martinez B, M. R.; Ortiz R, J. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Av. Ramon Lopez Velarde No. 801, Col. Centro, Zacatecas (Mexico)], e-mail: mrosariomb@yahoo.com.mx

    2009-10-15

    By using the integrated accounts of spectrometric system of Bonner spheres is possible to reconstruct the neutron spectrum using various methods such as: Monte Carlo, the parameterization and iterative methods. The response matrix, counting rates and neutron spectrum are intimately related through the integral-differential of Fredholm of first type. however, the weight of Bonner spheres system, the procedure of spectra reconstruction, the need of a expert user, the high time consumption, the need to use a reconstruction code (BUNKI, SAND, among others) and the spectrum resolution, are some of problems that this system presents. The above difficulties have motivated the development of complementary procedures such as maximum entropy, genetic algorithms and artificial neural networks. In recent years, using neural network technology has become an alternative procedure in the nuclear science research area, considering a replacement for classical techniques used for years. In previous works, was used a new method called robust design methodology of artificial neural networks, to construct various network topologies capable of solving the problems of neutron spectrometry and dosimetry, however noted that not exist tools for end-user that allow test and validate the designed networks. This paper presents the development of a software for neutronic spectrometry and dosimetry, based on information extracted from an artificial neural network designed in previous work, through the robust design methodology of artificial neural networks with the following characteristics: was designed in a user graphical interface easy to use, speed on the application execution, unlike other deconvolution codes, not is necessary to select and initial spectrum for spectrum reconstruction, as an additional element to this tool, besides spectrum, the calculation is performed simultaneous of 13 equivalent dose from just counting rates from a spectrometric system of Bonner spheres. (Author)

  7. Biological dosimetry after criticality accidents. Intercomparison exercise in the Silene Reactor - France; Dosimetria biologica en accidentes de criticidad. Ejercicio de intercomparacion en el Reactor Silene - Francia

    Energy Technology Data Exchange (ETDEWEB)

    Di Giorgio, Marina; Vallerga, Maria B; Taja, Maria R [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); arn gov ar, E-mail: mdigiorg@cae

    2004-07-01

    The Institute of Radiation Protection and Nuclear Safety Institute (IRSN) organized an international biological dosimetry intercomparison, at the SILENE experimental reactor (Valduc, France), simulating different criticality scenarios: bare source 4 Gy, lead shield source 1 and 2 Gy and gamma pure {sup 60}Co source 2 Gy. Fifteen laboratories were involved in this exercise, including the Argentine Biological Dosimetry Laboratory. The purposes of the intercomparison were: 1) To compare the unstable chromosome aberration (UCA) frequency observed by the different laboratories; and 2) To compare the dose estimation for gamma rays and neutrons. The objects of the present work were: I) To compare the mean frequency of UCA observed by the Argentine laboratory with the mean frequency observed by the participant laboratories as a whole. II) To compare the dose estimates performed by the Argentine lab with those estimated by the other laboratories involved in the second stage of the intercomparison. Overall, the mean frequencies of UCA and the correspondent 95% confidence limits obtained by the Argentine lab were consistent with the results obtained by the laboratories as a whole. For the gamma pure scenario, smaller variations were observed among laboratories in terms of dose (CV=18,2%) than in terms of frequency (CV=30,1%). For the mixed field scenarios, only four laboratories, including the Argentine lab, estimated gamma and neutron components of the total dose and just two (Argentine lab and lab 12) were in agreement with the given physical doses. The 1 Gy experiment presented lesser variations both in terms of frequency and dose than the other two scenarios. For the 4 and 2 Gy experiments, variations in neutron dose were more significant than variations in gamma dose, related to the magnitude of the dose. The results suggest that intercomparison exercises jointly with the accreditation of biological dosimetry by cytogenetic service laboratories, in compliance with ISO/IEC 17025, would allow to unify the protocols applied regarding: techniques, metaphase selection and scoring process. Thus, the dosimetric response in accidental overexposures that would require cooperation among countries, will be improved. (author)

  8. Production of LiF films for dosimetric thermoluminescence application; Producao de filmes de LiF para aplicacao em dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Mauricio, Claudia Lucia de Pinho

    2000-12-01

    This work studies the LiF monolayer and multilayer polycrystalline film's dosimetric properties. The films were produced by electron beam evaporation technique in aluminium and stainless steel substrates maintained at several temperatures. As dosimetric variable, the intensity of the thermoluminescent (TL) glow curve of the films was used. effects of the substrate type and temperature; of the addition of layers of Mg F{sub 2} NaF and Cu F{sub 2} to the LiF films; and of thermal treatments in the TL response of the produced films were studied. The microstructural characterization of the films was accomplished through measures of scanning electronic microscopy and grazing incidence X-rays diffraction analysis. The dosimetric characterization was made of gamma radiation exposure in a {sup 60} Co source, with kerma from 0,1 to 500 Gy. Studies of reproducibility, homogeneity, stability and other environmental effects were also made. LiF and Cu F{sub 2}: LiF; Mg F{sub 2} films were the only ones that presented mechanical stability and reproducibility of the TL emission. There is a strong indication of some correlation between the residual tension fields inside the films and the intensity of its TL emission peaks. LiF monolayer films present supralinear behaviour from 0,2 to 100 Gy. These films present a main TL glow peak around 150 deg C, whose half-time is about 30 days. Its volumetric sensitivity can reach about 60 times that of LiF powder and about 0,25 that of TLD100 (LiF:Mg, Ti commercial dosimeter from Harshaw Chemical Co.) The homogeneity and reproducibility inside a same film batch is better than 12% for 95% confidence level. Cu F{sub 2} : LiF: Mg F{sub 2} films present linear behaviour from 3 to 500 Gy and its main TL glow peak around 200 deg C did not present any fading for a a period of 30 days, in laboratory conditions. This glow peak is characteristic of the Mg doping of LiF, which confirms the diffusion of Mg ions from the Mg F{sub 2} layer to the LiF layer. The TL volumetric sensitivity of these films is about four times that of LiF powder and about 1% that of TLD 100. The homogeneity and reproducibility inside a same film batch is better than 20% for 95% of confidence level. (author)

  9. Neutron spectrometry and dosimetry by means of evolutive neural networks; Espectrometria y dosimetria de neutrones por medio de redes neuronales evolutivas

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz R, J.M.; Martinez B, M.R.; Vega C, H.R. [UAZ, Av. Ramon Lopez Velarde Num. 801, 98000 Zacatecas (Mexico)

    2008-07-01

    The artificial neural networks and the genetic algorithms are two relatively new areas of research, which have been subject to a growing interest during the last years. Both models are inspired by the nature, however, the neural networks are interested in the learning of a single individual, which is defined as fenotypic learning, while the evolutionary algorithms are interested in the adaptation of a population to a changing environment, that which is defined as genotypic learning. Recently, the use of the technology of neural networks has been applied with success in the area of the nuclear sciences, mainly in the areas of neutron spectrometry and dosimetry. The structure (network topology), as well as the learning parameters of a neural network, are factors that contribute in a significant way with the acting of the same one, however, it has been observed that the investigators in this area, carry out the selection of the network parameters through the essay and error technique, that which produces neural networks of poor performance and low generalization capacity. From the revised sources, it has been observed that the use of the evolutionary algorithms, seen as search techniques, it has allowed him to be possible to evolve and to optimize different properties of the neural networks, just as the initialization of the synaptic weights, the network architecture or the training algorithms without the human intervention. The objective of the present work is focused in analyzing the intersection of the neural networks and the evolutionary algorithms, analyzing like it is that the same ones can be used to help in the design processes and training of a neural network, this is, in the good selection of the structural parameters and of network learning, improving its generalization capacity, in such way that the same one is able to reconstruct in an efficient way neutron spectra and to calculate equivalent doses starting from the counting rates of a Bonner sphere spectrometric system. (Author)

  10. Thermoluminescent dosimetry of new phosphors of Zn O exposed to beta radiation; Dosimetria termoluminiscente de nuevos fosforos de ZnO expuestos a radiacion beta

    Energy Technology Data Exchange (ETDEWEB)

    Cruz V, C.; Burruel I, S.E.; Grijalva M, H. [UNISON, A.P. 130, Hermosillo, Sonora (Mexico); Barboza F, M.; Bernal, R. [CIF, UNISON, A.P. 5-088, Hermosillo, Sonora (Mexico)

    2004-07-01

    In this work, we report the thermoluminescence dosimetry of a new Zn O phosphor obtained by annealing of Zn S powder precipitated when Zn S films were grown by employing a CBD method. The collected Zn S powder was pressed in a die to form pellets which were subjected to different thermal treatments under air atmosphere. X-ray diffraction (XRD) patterns and energy-dispersive X-ray Spectrometry (EDS) analyses confirmed the transformation of Zn S to Zn O. The phosphors thus obtained were exposed to high doses of beta radiation and their thermoluminescent dosimetry show that these new phosphors are materials suitable to be used in high dose thermoluminescence dosimetry. (Author)

  11. The Pelletron Accelerator of IFUNAM and its possible applications to the dosimetry; El Acelerador Pelletron del IFUNAM y sus posibles aplicaciones a la dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Rickards, J. [Instituto de Fisica, UNAM, Circuito Exterior, C.U. 04510 Mexico D.F. (Mexico)

    1999-07-01

    The Pelletron Accelerator of positive ions 3 MV in the Institute of Physics of UNAM has characteristics that make it useful for the application to the radiations dosimetry. It is ideal for studying the detailed mechanisms of the radiation interaction with matter, therefore it can be applied to know the performance of dosemeters. With this device can be accelerated almost any type of ion, including He, but excepting the others noble gases. The energies of the disposable ions are in the interval 1 MeV until several MeV, depending of the state of charge selected, the energy can be varied continuously with accuracy of some KeV. It can be achieved streams from 10{sup 4} until 10{sup 6} ions/cm{sup 2}, allowing studies of individual events (tracks) or of collective processes. the beam size can be varying from a diameter 1 mm until 5 cm. It is also took in account with detectors and other techniques associated that can be combined for supporting studies, as surface barrier detectors and of other types, as well as the RBS, PIXE, RN techniques and channeling. (Author)

  12. Dosimetry through the Secondary Laboratory of Dosimetric Calibration of Mexico; Dosimetria a traves del Laboratorio Secundario de Calibracion Dosimetrica de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tovar M, V.M.; Alvarez R, J.T.; Medina O, V.P.; Vergara M, F.; Anaya M, R.; Cejudo A, J.; Salinas L, B. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2004-07-01

    In the beginnings of the sixty years an urgent necessity is presented mainly in the developing countries, of improving in important form the accuracy in the dosimetry of external faces in therapy of radiations (radiotherapy centers), mainly in the calibration of ''clinical dosemeters''. In 1976 the International Atomic Energy Agency, (IAEA), and the World Health Organization, (WHO), they carried out a mutual agreement with regard to the establishment and operation of a net of Secondary Patron Laboratories of Dosimetry, (LSCD). The necessity to establish measure patterns in the field of the dosimetry of the ionizing radiations, is necessary, to have an accuracy but high in the dosimetry of the radiation beams in therapy which is highly dependent of the dose given to the tumor of those patient with cancer. Similar levels of accuracy are required in protection measures to the radiation with an acceptable smaller accuracy, however, when the personal dosemeters are used to determine the doses received by the individuals under work conditions, such mensurations in therapy of radiations and radiological protection will have traceability through a chain of comparisons to primary or national patterns. The traceability is necessary to assure the accuracy and acceptability of the dosimetric measures, as well as, the legal and economic implications. The traceability is also necessary in the dosimetry of high dose like in the sterilization of different products. The main function of the LSCD is to provide a service in metrology of ionizing radiations, maintaining the secondary or national patterns, which have a traceability to the International System of measures, which is based for if same in the comparison of patterns in the Primary Laboratories of Dosimetry (LPD) under the auspice of the International Office of Weights and Measure (BIPM). The secondary and national patterns in the LSCD constitute in Mexico, the national patterns of the magnitudes in the dosimetry of the ionizing radiations. The net of the LSCD of the IAEA/WHO counts the international support to promote the objectives of improving the accuracy in dosimetry measures, particularly in radiotherapy centers, radiological protection and irradiation of different products, as well as, to transfer the dosimetric magnitudes and the distribution of the knowledge in applied dosimetry. The net of LSCD of the IAEA has 69 laboratories in the world in 58 states affiliated members, 13 primary laboratories (Germany, Australia, Austria, Canada, France, Hungary, Italy, Japan, Holland, Russia, United Kingdom, United States), 5 international organizations (ICRU, BIPM, IOMP, IEC, IOML). The first Standard Regional Center of Calibration and Dosimetry in Mexico settled down in the year of 1974 in the Department of Radiotherapy of the Hospital General of Mexico of the Secretary of Health SSA of Mexico. It was working until the year of 1985 when an earthquake in Mexico City destroys great part of its infrastructure. Later on in the year of 1986, the Standard Regional Center of Calibration and Dosimetry, for agreement of the SSA and of the National Institute of Nuclear Research, ININ, step to the Department of Metrology of the ININ. (Author)

  13. Personal dosimetry TLD 100 in orthopedic surgeons exposed to ionizing radiation in Bogota - Colombia; Dosimetria personal TLD 110 en medicos ortopedistas expuestos a radiacion ionizante en Bogota - Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Sierra C, B. Y.; Jimenez, Y. [Universidad Nacional de Colombia, Departamento de Fisica, Grupo de Fisica Medica, Carrera 45 No. 26-85, Bogota (Colombia); Plazas, M. C. [Hospital Universitario Fundacion Santa Fe de Bogota, Instituto de Oncologia Carlos Ardila Lulle, Calle 119, No. 7-90, 220246 Bogota (Colombia); Eslava S, J. [Universidad Nacional de Colombia, Instituto de Investigaciones Clinicas, Grupo Equidad en Salud, Carrera 45 No. 26-85, Bogota (Colombia); Groot R, H., E-mail: brigith.sierra@gmail.com [Universidad de los Andes, Laboratorio de Genetica Humana, Carrera 1 No. 18A -12, Bogota (Colombia)

    2014-08-15

    Orthopedic surgeons should be considered as professionals occupationally exposed to ionizing radiation, for using C arc (fluoroscope) an equipment of X type radiation emission, during surgical procedures for imaging generation. Some health institutes, use of C arc under uncontrolled circumstances, such a lack of dosimetry control, incomplete or absence of personnel protective elements and protective measures, which in turn, lead to a high exposition to the personnel. Materials and methods. Study of double match cohort by age and gender, was conducted, in four health institutions of second and third level of attention in Bogota city. Personal dosimetry measurements with TLD-100 dosimetry crystals in both cohorts and environmental dosimetry in each of operation rooms used for orthopedic procedures, were carry out during six months of follow up. Dosimetry crystals were read in a Harshaw 4500 - Bicron equipment, in the Medical Physics Laboratory of National University of Colombia. Results. Dosimetry measurements are compatibles with those of occupationally exposed personnel 3.44 mSv/6 m CI 95% (1.66-3.99), even does not overpass ICRP recommendations, are higher as were expect at the beginning of the study. The median of effective accumulative dose in thorax is 3,4 mSv CI 95% (1,66-3,99), higher in comparison with neck value 2,7 mSv CI 95% (1,73-3,80) and hand dosimetry 1,42 mSv CI 95% (0,96-2,34). Conclusions: Orthopedic surgeons should be considered occupational exposed to ionizing radiation, who has to accomplish to the radiological protection measures, dosimetric follow up and maintenance of the used X ray equipment. It was confirm throughout this study that dosimetry shows higher levels as expected at the beginning of the study, compatible with occupationally exposed personnel. (Author)

  14. TL Dosimetry on the Tandetron Ion Accelerator area of the ININ; Dosimetria TL en el area del Acelerador de iones Tandetron del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valdovinos A, M.A.; Gonzalez M, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    For the fulfilment of the operation tests of the Positive Ions type Tandetron 4120 MC, 2 MV, it was obtained the permission consented by the National Commission of Nuclear safety and safeguards (CNSNS). During the stage of tests were arranged Tl dosemeters in the Tandetron Accelerator area, as well as toward to the beam exit. In this work, it was presented the results obtained of the measurement of radiation levels, as much in the area as in the beam exit. This Accelerator is useful in different fields of science such as: biology, radiochemistry, materials, solid state physics, archaeology and environmental sciences between others. (Author)

  15. A new Implementation of the multi-channel analysis in the dosimetry through radiochromic films; Una nueva implementacion del analisis multicanal en la dosimetria mediante peliculas radiocromicas

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, C.; Martin Martin, G.; Bermudez Luna, R.; Lopez Fernandez, A.; Torres Olombrada, M. V. de; Garcia Canibano, T.; Caballero Guerra, P.

    2013-07-01

    The objectives of this study are to implement multi-channel analysis algorithm using open source tools, extend the application of the same to a scanner other than the supported by Micke, generate maps of dose absorbed in compatible format with the PTW Verisoft quality control program and to quantify the improvement in the results of the gamma index as to what would be obtained by applying a conventional single-channel analysis. (Author)

  16. Development and implementation of own software for dosimetry multichannel film; Desarrollo e implementacion de un software propio para la dosimetria multicanal con pelicula radiocromica EBT2

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Feltstrom, D.; Reyes Garcia, R.; Luis Simon, F. J.; Carrasco Herrera, M.; Sanchez Carmona, G.; Herrador Cordoba, M.

    2013-07-01

    The objective of this work is to develop its own software for multichannel film dosimetry Radiochromic EBT2. Compare the results obtained with its use in multichannel and single-channel dosimetry. Check that the multi-channel dosimetry eliminates much of the artifacts caused by dirt, fingerprints, scratches, etc. Radiochromic in film and scanner devices. (Author)

  17. Experimental verification of a new neutron spectrometer for environmental dosimetry and area; Verficiacion experimental de un nuevo espectrometro de neutrones para dosimetria ambiental y de area

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ros, J. M.; Romero, A.; Begogini, R.; Esposito, A.; Moraleda, M.; Lagares, J. I.; Sansaloni, F.; Arce, P.; Llop, J.

    2011-07-01

    In this communication, we present experimental results with a new neutron spectrometer, developed jointly by the Radiation Dosimetry Unit of CIEMAT Unita di Fisica and INFN-LNF Sanitary (Italy), consisting of a polyethylene moderating sphere detectors thermal neutrons (paired thermoluminescent dosimeters and activation foils) located in different positions. The device configuration and distribution of dosimeters are designed to elicit a response in a nearly isotropic up to 20 MeV energy range. (Author)

  18. Determination of effective dose for workers hemodynamics service using double dosimetry; Determinacion de la dosis efectiva para los trabajadores del servicio de hemodinamica usando doble dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Lopez, M. A.; Lobato Munoz, M.; Jodar Lopez, C. A.; Ramirez Ros, J. C.; Jerez Sainz, M. I.; Pamos Urena, M.; Carrasco Rodriguez, J. L.

    2013-07-01

    The use of an additional dosimeter at the level of the neck above the lead apron we can provide an indication of the dose in the head (the Crystal dose). In addition, it is possible to combine the two readings of the dosimeter to provide an improved estimate of the effective dose. In the hemodynamics service of our Hospital we have maintained a worker for 3 years with the double dosimetry read monthly. With the readings from these dosimeters will do following algorithms, several estimates of the effective dose to see if, with working conditions that occur in this service, it would be necessary to extend this practice to the rest of the workers to get a better estimation of effective dose. (Author)

  19. Experience of the new service of dosimetry internal by Bio elimination of Tecnatom; Experiencia del nuevo servicio de dosimetria interna por bioeliminacion de Tecnatom

    Energy Technology Data Exchange (ETDEWEB)

    Duran, T.; Navas Menchen, C.; Campos Mendia, J.

    2012-07-01

    Internal dosimetry is of particular relevance for occupationally exposed workers in the field of nuclear decommissioning and radioactive facilities. The tasks to be performed at these facilities involve an increase in the risk of incorporation of radioactive material into the body, the radioactive waste generated diverse in nature and involve work that may lead to a greater dispersion of radioactive material.

  20. ISO 9001 certification in the clinical dosimetry process in physics medical service; Certificacion ISO9001 en el proceso de dosimetria clinica en un servicio de fisica medica

    Energy Technology Data Exchange (ETDEWEB)

    Font Gomez, J. A.; Andres Redondo, M. M.; Gandia Martinez, A.; Jimenez Albericio, F. J.; Mengual Gil, M. A.

    2013-07-01

    The objective of this work is to simply name a series of procedures that are part of the certification and technical instructions (manuals about how to perform specific tasks) without going into details. (Author)

  1. Development of pathological anthropomorphic models using 3D modelling techniques for numerical dosimetry; Desenvolvimento de modelos antropomorficos patologicos usando tecnicas de modelagem 3D para dosimetria numerica

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Kleber Souza Silva [Faculdade Integrada de Pernambuco (FACIPE), Recife, PE (Brazil); Barbosa, Antonio Konrado de Santana; Vieira, Jose Wilson [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco, Recife, PE (Brazil); Lima, Fernando Roberto de Andrade, E-mail: falima@cnen.gov.b [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2011-10-26

    Computational exposure models can be used to estimate human body absorbed dose in a series of situations such as X-Ray exams for diagnosis, accidents and medical treatments. These models are fundamentally composed of an anthropomorphic simulator (phantom), an algorithm that simulates a radioactive source and a Monte Carlo Code. The accuracy of data obtained in the simulation is strongly connected to the adequacy of such simulation to the real situation. The phantoms are one of the key factors for the researcher manipulation. They are generally developed in supine position and its anatomy is patronized by compiled data from international institutions such as ICRP or ICRU. Several pathologies modify the structure of organs and body tissues. In order to measure how significant these alterations are, an anthropomorphic model was developed for this study: patient mastectomies. This model was developed using voxel phantom FASH and then coupled with EGSnrc Monte Carlo code

  2. Biological dosimetry of ionizing radiation by chromosomal aberration analysis; Dosimetria biologica de las radiaciones ionizantes mediante el analisis de aberraciones cromosomicas

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Castano, S.; Silva, A.; Navlet, J.

    1990-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y ={alpha} + {beta}{sub 1}D + {beta}{sub 2}D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs.

  3. EPR response characterization of drugs excipients for applying in accident dosimetry; Caracterizacao da resposta RPE dos excipientes dos medicamentos para aplicacao em dosimetria de acidente

    Energy Technology Data Exchange (ETDEWEB)

    Marczewski, Barbara S.; Rodrigues Junior, Orlando; Galante, Ocimar L.; Costa, Zelia M. da; Campos, Leticia L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2002-07-01

    Some drugs are widely used by the population and can be employed to dose retrospective. The carbohydrates (saccharides), commonly used as excipients in the pharmaceutical industry, produce a quantity of free radicals after gamma irradiation, making them useful for dosimetry in emergency or accident situations that imply in dose evaluation from the materials found nearly or in contact with victims. In general, EPR signal from pulverized pills of some drugs are very complex due to the variety of components in the formulation. Because of this fact, some pharmaceutical excipients identified in the pill composition were also analysed by EPR spectrometry. On the counter drugs were studied: Cebion glucose, AAS, Aspirina, Conmel, Lacto-Purga and sugar substitutive ZeroCal. The excipients were: lactose, amide, anhydrous glucose and magnesium stearate. In some samples the number of radicals produced increased with the dose, showing a linear response for a dose range of interest and an adequate sensibility for dosimetry in accident cases.

  4. Use of Fricke solution modified with dyes for dosimetry in phototherapeutic treatments; Uso da solucao Fricke modificada com corantes para futura dosimetria em tratamentos fototerapeuticos

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Mayara Gabriella Oliveira de; Nascimento, Rizia Keila; Vieira, Rafaela Etelvina de Amorim; Souza, Vivianne Lucia Bormann, E-mail: mayaradqf@hotmail.com, E-mail: riziakeila@hotmail.com, E-mail: rafaelarodriguesss@hotmail.com, E-mail: vlsouza@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife (Brazil)

    2014-07-01

    Dyes and pigments (photosensitizers) are characterized by their ability to absorb visible light, and to participate in photochemical reactions. These colors are used in medicine in the dose recommended for use in photodynamic therapy (PDT). There are lasers that can meet most of the phototherapeutic agents and are capable of providing light of considerable power with precision on the injured tissue. The use of light emitting diodes (LEDs) have become feasible, thus reducing the cost of the procedures. The Dosimetry Laboratory Chemistry of the CRCN-NE/Brazilian CNEN has worked with some likely dye use in phototherapy treatments, including: methylene blue, malachite green and toluidine blue. A volume of 2.6 ml of the dosimeters was transferred to test tubes and these were irradiated with LED 24, 48, 72 and 96 acrylic simulator 110 mm x 110 mm x 80 mm at a distance of 6.5 cm from reading light source of the irradiated samples was performed on a spectrophotometer. Having obtaining excellent correlations (above 0.97) to the dosimeter calibration curves. Suggests that the dosimeter can be applied to perform a quality control in photodynamic therapy. However, further experiments should be performed before a wide application of this technique. A volume of 2.6 ml of the dosimeters was transferred to test tubes and these were irradiated with LED 24, 48, 72 and 96 acrylic simulator 110 mm x 110 mm x 80 mm at a distance of 6.5 cm from reading light source of the irradiated samples was performed on a spectrophotometer. Having obtaining excellent correlations (above 0.97) to the dosimeter calibration curves. Suggests that the dosimeter can be applied to perform a quality control in photodynamic therapy. However, further experiments should be performed before a wide application of this technique.

  5. Dosimetry for the treatment of cystic craniopharyngioma through radiocolloids with {sup 186} Re; Dosimetria para el tratamiento de craneofaringiomas quisticos mediante radiocoloide con {sup 186} Re

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, E.L.; Al-dweri, F.M.O.; Lallena, A.M. [Depto. de Fisica Moderna, Universidad de Granada (Spain); Bodineau, C.; Galan, P. [Servicio de Radiofisica Hospitalaria, Hospital Regional Universitario ' Carlos Haya' , 29010 Malaga (Spain)

    2003-07-01

    The cystic craniopharyngioma (CQ) are histologically benign tumors that can affect important organs, as the hypothalamus or the optic nerve. They are treated introducing, inside the cyst, a radioactive colloid. The wall constitutes the white volume and the dosimetry is usually carried out starting from analytic formulas that only are valid in the case of an homogeneous media, uniform and infinite. In this work it is studied the dosimetry of the CQ by means of Monte Carlo simulation (MC), taking in account the different materials and interfaces that conform them. We present the obtained results for the radionuclide {sup 186} Re. We have used the Monte Carlo code Penelope and we follow 5x10{sup 6} histories in each simulation. We supposed a size of CQ of 1.75 cm of radio and a wall thickness of 1 mm and we have varied the constituent materials of the interior of the cyst and of the wall. The analytic calculations that we carry out show an excellent agreement with the MC results for an unique media (water), as much for the beta radiation as for those originated of the Rhenium disintegration. However, when it takes in account the gel that is introduced in the tumor for the treatment and we vary the constituent material of the wall, we find important differences. Of the analysis of our results we can conclude that the dosimetry for the treatment of CQ based in the usual analytic formulas overestimates the doses really deposited in the wall of the CQ. (Author)

  6. Test and validation of the iterative code for the neutrons spectrometry and dosimetry: NSDUAZ; Prueba y validacion del codigo iterativo para la espectrometria y dosimetria de neutrones: NSDUAZ

    Energy Technology Data Exchange (ETDEWEB)

    Reyes H, A.; Ortiz R, J. M.; Reyes A, A.; Castaneda M, R.; Solis S, L. O.; Vega C, H. R., E-mail: alfredo_reyesh@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Ingenieria Electrica, Av. Lopez Velarde 801, Col. Centro, 98000 Zacatecas (Mexico)

    2014-08-15

    In this work was realized the test and validation of an iterative code for neutronic spectrometry known as Neutron Spectrometry and Dosimetry of the Universidad Autonoma de Zacatecas (NSDUAZ). This code was designed in a user graph interface, friendly and intuitive in the environment programming of LabVIEW using the iterative algorithm known as SPUNIT. The main characteristics of the program are: the automatic selection of the initial spectrum starting from the neutrons spectra catalog compiled by the International Atomic Energy Agency, the possibility to generate a report in HTML format that shows in graph and numeric way the neutrons flowing and calculates the ambient dose equivalent with base to this. To prove the designed code, the count rates of a spectrometer system of Bonner spheres were used with a detector of {sup 6}LiI(Eu) with 7 polyethylene spheres with diameter of 0, 2, 3, 5, 8, 10 and 12. The count rates measured with two neutron sources: {sup 252}Cf and {sup 239}PuBe were used to validate the code, the obtained results were compared against those obtained using the BUNKIUT code. We find that the reconstructed spectra present an error that is inside the limit reported in the literature that oscillates around 15%. Therefore, it was concluded that the designed code presents similar results to those techniques used at the present time. (Author)

  7. Quality control of radiosurgery: dosimetry with micro camera in spherical mannequin; Control de calidad en radiocirugia: dosimetria con microcamara en maniqui esferico

    Energy Technology Data Exchange (ETDEWEB)

    Casado Villalon, F. J.; Navarro Guirado, F.; Garci Pareja, S.; Benitez Villegas, E. M.; Galan Montenegro, P.; Moreno Saiz, C.

    2013-07-01

    The dosimetry of small field is part of quality control in the treatment of cranial radiosurgery. In this work the results of absorbed dose in the isocenter, Planner, with those obtained from are compared experimentally with a micro-camera into an spherical mannequin. (Author)

  8. Biological dosimetry of patients with differenced carcinoma of thyroid treated with Iodine-131; Dosimetria biologica de pacientes con carcinoma diferenciado de tiroides tratados con Iodo-131

    Energy Technology Data Exchange (ETDEWEB)

    Vallerga, M. B.; Rojo, A.M.; Taja, M.R.; Deluca, G.; Di Giorgio, M. [Autoridad Regulatoria Nuclear Av. Del Libertador 8250 (C1429BNP). Buenos Aires (Argentina); Fadel, A. [Hospital General de Agudos Dr. Carlos Durand Av. Diaz Velez 5044. Buenos Aires (Argentina); Cabrejas, M.; Valdivieso, C. [Hospital de Clfnicas Jose de San Martin Av. Cordoba 2351 (CP1120). Buenos Aires (Argentina)]. e-mail: mvallerg@cae.arn.gov.ar

    2006-07-01

    The administration of I-131 to patient with Differentiated Thyroid Carcinoma (CaDiT) it is used inside the therapeutic outline as later step to the thyroidectomy. However, the good activity to give is of difficult determination due to factors such as, the variability in the capacity of tumoral reception of the I-131, distribution of the pharmaceutical, physiologic status, other associate pathologies, grade of advance of the illness, and previous treatments. Additionally, the activity to administer is dependent of the dose of tolerance in the healthy tissues; superior dose to 2 Gy in bone marrow, its could drive to myelotoxicity. At the moment, the form more extended of administration it is the empiric prescription that considers clinical parameters and of laboratory for their determination. Presently work, the protocol of applied treatment incorporates the evaluation for internal dosimetry and biological dosimetry to estimate absorbed dose in bone marrow. The biological estimate of the dose of these patients is based on the quantification of chromosomal aberrations whose frequency is referred to a curve-dose response in which the lymphocytes is irradiated in vitro with I-131, allowing to determine the in vivo dose to the patient's circulating lymphocytes. The objective of the present work is to determine the applicability of different cytogenetic essays in the estimate of the absorbed dose to the whole body or specific organs. Three patients were evaluated with CaDiT. Their treatment protocol consisted on a tracer administration of radioactive iodine of 74 - 111 MBq (2 - 3 mCi) and a therapy 7,4 - 11,1 GBq (200 - 300 mCi). Previous to the tracer administration and 8 days post-therapeutic administration took samples of veined blood that were evaluated by biological dosimetry by means of the application of the techniques: conventional cytogenetic Micronucleus and FISH (Hybridization in situ by Fluorescence). Starting from the frequencies of observed chromosomal aberrations it was considered absorbed dose to whole body. The obtained doses were compared by the different biological methods used. The evaluation by internal dosimetry of the data obtained tracer post-activity allowed to personalize the activity of I-131 to administer, starting from physical-mathematical models that consider the particular biokinetics of each patient (MIRD methodology). The doses estimated by the used biological dosemeters were consistent among them. It was discussed its scopes and limitations to be applied in the validation of the dosimetric estimation based on models, in order to administer a therapeutic dose protecting the patient of the adverse effects of the internal radiotherapy in organs that are not target of the same one. The acquired experience is considered of utility to give answer in cases of radioiodine incorporation in occupationally exposed personnel. (Author)

  9. Internal dosimetry for [4-{sup 14}C]-cholesterol in humans; Dosimetria interna para o [4-{sup 14}C]-colesterol em humanos

    Energy Technology Data Exchange (ETDEWEB)

    Marcato, Larissa Andreto

    2012-07-01

    The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose due to intake of [4-{sup 14}C]-cholesterol. The model was validated comparing the values of fecal excretion and absorption described in literature with that predicted by the model. The proposed model achieved good concordance between the results (p = 0.416 for excretion and p = 0.423 for absorption). The coefficients of effective dose (SvBq{sup -1}), equivalent dose (SvBq{sup -1}) and absorbed dose (GyBq{sup -1}) in human organs and tissues were calculated using the MIRD methodology and the compartmental analysis software ANACOMP. The coefficients were estimated for four phantoms: adult with a body mass of 73.3 kg, 15 years old adolescent (56.9 kg), 10 years old child (33.2 kg) and five years old child (19.8 kg). The organ that received the highest absorbed dose for all phantoms was the lower large intestine (LLI). The allometry theory was used to interpolate the coefficient of absorbed dose in the lower large intestine (DLLI) for unknown body mass (m): DLLI (GyBq{sup -1})=161.26 m (kg){sup -1.025}. For the same administered activity, the effective dose coefficient (E) decreases as the body mass increases. On other words, for the same intake activity, individuals with low body mass are exposed to higher doses. The allometry theory was used to interpolate the coefficient effective dose (E) for unknown body mass (m): E(SvB{sup -1})= 171.1 m(kg){sup -1,021}. (author)

  10. Dosimetria comparativa de braquiterapia de próstata com sementes de I-125 e Pd-103 via SISCODES/MCNP

    OpenAIRE

    Trindade, Bruno Machado; Christóvão, Marília Tavares; Trindade, Daniela de Fátima Maia; Falcão, Patrícia Lima; Campos, Tarcisio Passos Ribeiro de

    2012-01-01

    OBJETIVO: O presente artigo visa apresentar um estudo dosimétrico comparativo de braquiterapia de próstata com sementes de I-125 e Pd-103. MATERIAIS E MÉTODOS: Um protocolo adotado para ambos os implantes com 148 sementes foi simulado em um fantoma tridimensional heterogêneo de pelve por meio dos códigos SISCODES/MCNP5. Histogramas dose-volume na próstata, bexiga e reto, índices de doses D10, D30, D90, D0,5cc, D2cc e D7cc, e representações de distribuição espacial de dose foram avaliados. RES...

  11. TLD personnel dosimetry and its relationship with the radiodiagnostic training; Dosimetria personal TLD y su relacion con la capacitacion en radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E.; Franco E, J.G. [DEHA, Universidad Autonoma Metropolitana-Xochimilco, Mexico D.F. (Mexico); Gaona C, E. [Universidad Tecnologica de Mexico, Mexico D.F. (Mexico)

    2002-07-01

    The personnel dosimetry and the training in radiological protection in radiodiagnostic in Mexico before 1997 were almost nonexistent except few services of public and private radiology, we can to say that the personnel dosimetry and the obligatory training was born in the year 1997, together with the present Mexican Official Standards in radiology. This study has the purpose to make an evaluation of the personnel dosimetry of 110 radiology services distributed in the Mexican Republic for the year 2001 and to estimate the annual and bimonthly mean doses, as well as its trust intervals and its relationships with the personnel training in radiological protection by means of a sampling that was realized in two stages (1997 and 2000) in the metropolitan area of Mexico City. The results show that the received doses by the medical and technical personnel in the participating radiology services are in the 0.03 mSv and 0.94 mSv interval and the mean is 0.25 mSv. The estimated annual personnel dose would be in the 0.18 mSv to 5.64 mSv interval, which are values very lower to the annual dose limit that is 50 mSv and its magnitude is similar to the effective annual dose by natural background radiation. In the first stage in training was found that there is not a significant difference in the response frequencies among the medical and technical personnel with a p < 0.05. The 52% of the occupational exposure personnel of radiology uses dosemeter, but only 17% of them know the dose reports. the 15.8% of personnel considers that dosemeter protects against radiation and only 16.5% knows the annual maximum permissible dose for stochastic effects. The second stage, the results shown that there is a significant difference in the response of frequencies among medical and technical personnel, the same results which are obtained for members and non members of a professional association with a p < 0.05. The 38% has personnel dosimetry, the 19% knows the principles of radiological protection. (Author)

  12. Determination of the components of uncertainty for a dosimetry system in radiation protection; Determinacion de las componentes de incertidumbre para un sistema de dosimetria en radio proteccion

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, F., E-mail: flopez@unan.edu.ni [Universidad Nacional Autonoma de Nicaragua, Managua (Nicaragua); Cabral, T.S.; Peixoto, J.G. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    This work is about the theoretical calculation of uncertainties associated to the dosimetry of photons of a {sup 137}Cs source that will be used in a Dosimetry Laboratory. In this case recognition of the influence quantities that provide most uncertainty and the right choice of resolution of auxiliary equipment to obtain the smallest uncertainties according to the laboratory. (author)

  13. Accreditation of a system of extremity dosimetry: validation and uncertainty of method; Acreditacion de un sistema de dosimetria de extremidades: validacion e incertidumbre del metodo

    Energy Technology Data Exchange (ETDEWEB)

    Romero Gutierrez, A. M.; Rodriguez Jimenez, R.; Lopez Moyano, J. L.

    2013-07-01

    The authors' goal is to spread the practical experience gained during the accreditation process paying special attention to the process of method validation and estimation uncertainty of the dosimetry system. (Author)

  14. Dosimetry for computed tomography using Fricke gel dosimetry and magnetic resonance imaging; Dosimetria em tomografia computadorizada empregando dosimetro Fricke gel e a tecnica de imageamento por ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Capeleti, Felipe Favaro; Campos, Leticia L., E-mail: felipe@gmpbrasil.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-04-15

    In this work it was determined a new method for the determination of absorbed doses in Computed Tomography (CT) examinations using Fricke gel dosimetry developed at IPEN. Absorbed doses were determined by different methods of analysis, such as optical absorption spectrometry, ionization chambers and magnetic resonance imaging. Lower limit of sensitivity of the Fricke gel solution, the solution repeatability signal Fricke gel and CT equipment, detection sensitivity, among other tests were performed. Different equipment of computed tomography with multiple detectors were used. The Fricke gel solution showed better repeatability than ±5.5% using the technique of optical absorption spectrophotometry and computed tomography equipment showed repeatability better than ±0.2%. The Fricke gel solution features an easy and relatively quick preparation, but it is necessary to be careful not to contaminate and lose the solution. With the results, it was confirmed the application of this type of dosimetry for computed tomography equipment. (author)

  15. Calibration methods of plane-parallel ionization chambers used in electron dosimetry; Metodos de calibracao de camaras de ionizacao de placas paralelas para dosimetria de feixes de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Bulla, Roseli Tadeu

    1999-07-01

    The use of linear accelerators in radiotherapy is of great importance in Medicine, and according to international recommendations the electron beam dosimetry has to be performed using plane-parallel ionization chambers, previously calibrated in standard gamma radiation fields at accredited laboratories. In this work, calibration methods of plane-parallel ionization chambers used in dosimetry procedures of high energy electron beams of clinical accelerators were presented, tested and intercompared. The experiments were carried out using gamma radiation beams of {sup 60} Co at the Calibration Laboratory of Clinical Dosemeters at IPEN and electron beams od 4 to 16 MeV at the Radiotherapy Department of Hospital Israelita Albert Einstein, Sao Paulo. A method was chosen to be established at IPEN. Proposals of the calibration procedure, calibration certificate and data sheets are presented. (author)

  16. Spectrometry and dosimetry of isotopic sources of neutrons by means of artificial neural networks; Espectrometria y dosimetria de fuentes isotopicas de neutrones mediante redes neuronales artificiales

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Ortiz R, J. M.; Hernandez D, V. M; Martinez B, M. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Gallego, E.; Lorente, A. [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, C/Jose Gutierrez Abascal No. 2, 28006 Madrid (Spain); Barquero, R., E-mail: fermineutron@yahoo.co [Hospital del Rio Hortega, C/Dulzaina No. 2, 47012 Valladolid (Spain)

    2010-09-15

    The artificial neural networks technology has been applied to reconstruct the neutrons spectra of two isotopic sources: {sup 252}Cf, and {sup 241}Am-Be. Also, this technology has been applied to obtain the effective dose, E, and the personal dose equivalents, Hp(10) and environmental, H *(10). To obtain the spectra and the doses only were used the count rates produced in a Bonner Spheres spectrometer with a scintillator of {sup 6}LiI(Eu) of 0.4 {phi} x 0.4 cm{sup 2}. The equivalent environmental dose and the spectra of the sources were also obtained by means of the reconstruction code BUNKIUT. When comparing the results obtained by means of both procedures it was found that they are consistent. (Author)

  17. Monte Carlo dosimetry in simple geometries with interfaces: applications in radiotherapy; Dosimetria Monte Carlo en geometrias simples con interfases: aplicaciones en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E.L

    2004-07-01

    In the last decade, dosimetry has evolved in an accelerated way due in part, to the development of new techniques and advances in instruments manufactured for several applications in Medical Physics. In order to improve achievements gotten with the use of radiation sources for therapeutic use, a guessed right dosimetry must be done and clinical data must be explained with the aid of investigation and supported with scientific bases. In this context, Monte Carlo (MC) method used to simulate radiation transport in materials, contribute with extensive knowledge and extremely useful information to that objective. MC dosimetry has some advantages over experimental and analytical dosimetry but it also has limitations. Maybe the most important is the computer time required to reach to an acceptable uncertainty level in a complex problem. Though this restrictive factor, a right application of MC simulation of radiation transport is a useful, reliable and versatile instrument for dosimetric calculations. From our point of view, the problem of heterogeneities in the sources or in the treatment targets in radiotherapy is of great importance, and this is the principal question to study aboard in this work. We use the MC simulation code Penelope to calculate some dosimetric quantities.The cases we study involve dosimetric aspects of different geometric distributions of radionuclides where interfaces are evident and must be taken into account. This work is divided in five chapters. In the first chapter we give a succinctly description of MC codes for simulation of the transport of particles in a medium and we describe the code Penelope. In chapter two, we study spherical distributions of radionuclides and the effect that interfaces in the target have in the dose received by the tumor. Specifically we study the application of radiocolloids with {sup 186} Re and {sup 32} P to treat homogeneous and nonhomogeneous cystic craniopharyngioma. Chapter three is dedicated to study plane distributions of radionuclides in presence of interfaces, particularly we deal with the injection of radiocolloids with {sup 165} Dy, {sup 32} P and {sup 90} Y into the knee joint with different healing purposes. The model is described and similar studies to those of chapter two, involving heterogeneities of the joint are presented. In chapter four, dosimetric studies of simulated treatments of radiosurgery of the head with the Leksell Gamma Knife are done. We describe the unit, give the simulation details and parameters and describe the targets. To make our investigation spheric interfaces of different materials in the phantoms are considered. Finally, a chapter with the conclusions is presented. References are given after this chapter. (Author)

  18. Dosimetria comparativa de braquiterapia de próstata com sementes de I-125 e Pd-103 via SISCODES/MCNP

    Directory of Open Access Journals (Sweden)

    Bruno Machado Trindade

    2012-10-01

    Full Text Available OBJETIVO: O presente artigo visa apresentar um estudo dosimétrico comparativo de braquiterapia de próstata com sementes de I-125 e Pd-103. MATERIAIS E MÉTODOS: Um protocolo adotado para ambos os implantes com 148 sementes foi simulado em um fantoma tridimensional heterogêneo de pelve por meio dos códigos SISCODES/MCNP5. Histogramas dose-volume na próstata, bexiga e reto, índices de doses D10, D30, D90, D0,5cc, D2cc e D7cc, e representações de distribuição espacial de dose foram avaliados. RESULTADOS: A atividade inicial de cada semente de I-125, para que D90 seja equivalente à dose de prescrição, foi calculada em 0,42 mCi, e de Pd-103, em 0,94 mCi. A dose máxima na uretra foi 90% e 108% da dose de prescrição para I-125 e Pd-103, respectivamente. A D2cc para I-125 foi 30 Gy no reto e 127 Gy na bexiga, e para Pd-103 foi 29 Gy no reto e 189 Gy na bexiga. A D10 no osso do púbis foi 144 Gy para I-125 e 66 Gy para Pd-103. CONCLUSÃO: Os resultados indicam que os implantes de Pd-103 e I-125 puderam depositar a dose prescrita no volume alvo. Entre os achados, observou-se excessiva exposição de radiação nos ossos da pelve, principalmente no protocolo com I-125.

  19. Quality assurance program in the External dosimetry laboratory of the CPHR; Programa de aseguramiento de la calidad en el laboratorio de dosimetria externa del CPHR

    Energy Technology Data Exchange (ETDEWEB)

    Molina P, D.; Pernas S, R.; Martinez H, E.; Cardenas H, J. [Centro de Proteccion e Higiene de las Radiaciones, Calle 20 No. 4113 e/41 y 47. Playa, C.P. 11300, A.P. 6195, C.P. 10600 La Habana (Cuba)

    2006-07-01

    From 1999 the Laboratory of External Dosimetry of the Radiation Protection and Hygiene Center comes applying in its service of personal dosimetry a Program of Quality Assurance. This program was designed according to the recommendations of national and international organizations as the National Assuring Office of the Republic of Cuba (ONARC), the International Standards Organization (ISO), the International Electro technique Commission (IEC) and the International Atomic Energy Agency (IAEA). In this work it is presented in a summarized way the operation of this Program of Quality Assurance which includes the administration and conservation of the results and the documentation of the service, the controls that are carried out to the equipment, the acceptance tests that are applied to the equipment and new dosemeters, the shipment and prosecution of the dosemeters, the evaluation, storage and conservation of the doses, the report of the results, the traceability and reproducibility of the measurements, the attention to the reclamations and the clients complaints and the internal and external audits to those that it undergoes periodically the laboratory. (Author)

  20. Kinetic and allometric models for dosimetry using radiopharmaceuticals labeled with lanthanides; Proposicao de modelos cineticos e alometricos para a dosimetria de radiofarmacos marcados com lantanideos

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Marina Ferreira

    2012-07-01

    This work proposes two models based in compartmental analyses: Animal model and Human model, using images from gamma camera measurements to determinate the kinetic constants of the {sup 177}Lu-DOTATATE to three animal species (rat Wistar, Armenian hamster and Syrian hamster) and to the human in biodistribution studies split in two phases: Phase 1 governed by uptake from the blood and Phase 2 governed by the real excretion. The kinetic constants obtained from the animals' data ere used to build allometric scaling to predict radiopharmaceutical biodistribution in the human employing relations by mass, metabolism, by life span and by physiological parameters. These extrapolation results were compared with the PRRT (Peptide receptor radiotherapy) patients kinetic data calculated using the Human model. The kinetic constants obtained from humans were used in dose assessment to PRRT patients considering MIRD 26 organs and tissues. Dosimetry results were in agreement with available results from literature. For the Phase 1 allometric scaling from kinetic data from the blood to the organs straight responsible for the {sup 177}Lu-DOTATATE metabolism and excretion - liver, kidneys and urinary bladder -show good correlation in the scaling by mass, metabolism and physiological and parameters. For the Phase 2, only the kinetic data from blood to the liver and to the kidneys show good correlation. Based in the anaesthetics inhibitory action over the renal excretion, there is not empirical basis to allow measurement times over 40 minutes in in vivo studies with small animals. Consequently, the Phase 1 results seem enough to make allometric scaling to assessment dose in PRRT. (author)

  1. Validation criteria of an internal dosimetry laboratory in vivo; Criterios para la validacion de un laboratorio de dosimetria interna in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M. de las M., E-mail: mercedes.alfaro@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    People working with radioactive materials, under certain circumstances (e.g. not using the proper protective equipment, an incident not covered, etc.) could be incorporated into the body. The radiation protection programs include direct measurement methods -in vivo- or indirect -in vitro- or both, to know that radioactive material is incorporated into the body. The monitoring measurements of internal contamination or (Radio-bioassay) are carried out with the purpose of determining the amount of radioactive material incorporated in the body; estimate the effective dose and committed dose; management administration of radiation protection; appropriate medical management; and to provide the data necessary for the legal requirements and the preservation of records. The measurement methods used in the monitoring of internal contamination must be validated by the combination of the following processes: calibration, using standards reference materials and/or simulators; execute systematic research, using control samples; and intercomparison between laboratories and performance tests. In this paper the validation criteria of an internal dosimetry laboratory in vivo are presented following the information provided by the standard ANSI N13-30-1996 and ISO/TEC 17025-2005 as are the criteria of facilities, staff training, interpretation of measurements, performance criteria for monitoring of internal contamination in vivo, results reporting and records retention. Thereby we achieve standardized quantitative performance criteria of truthfulness, accuracy and detection limit and a consensus on statistical definitions to establish the validation plan of a monitoring laboratory of internal contamination in vivo. (Author)

  2. Cytogenetics dosimetry: dose-response curve for low doses of X-ray; Dosimetria citogenetica: curva dosis-respuesta para bajas dosis de rayos-X

    Energy Technology Data Exchange (ETDEWEB)

    Lara, Virginia E. Noval; Pineda Bolivar, William R.; Riano, Victor M. Pabon, E-mail: venovall.15@hotmail.com, E-mail: wrpineda@misena.edu.co, E-mail: vmpabonr@udistrital.edu.co [Universidad Distrital Francisco Jose de Caldas (UD), Bogota (Colombia). Grupo de Investigacion en Ciencia y Tecnologia Nuclear; Ureana, Cecilia Crane, E-mail: cecicrane@yahoo.com [Instituto Nacional de Salud (INS), Bogota (Colombia). Laboratorio de Genetica

    2013-07-01

    The purpose of this study was to conduct a preliminary study for the standardization in the future, the dose-response curve for low doses of X-rays, through the analysis of in vitro cultures of peripheral blood samples of 3 men and 3 women occupationally not exposed to artificial sources of ionizing radiation, age 18-40 years, where possible nonsmokers.

  3. Alanine/RPE dosimetry in the process of blood irradiation; Dosimetria alanina/RPE en el proceso de irradiacion de sangre

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Covas, D.T.; Baffa, O. [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto-SP (Brazil)

    2000-07-01

    A set of eighty dosemeters approximately of Dl- alanine was proportioned to the Hemo center of Hospital das Clinicas of Medicine Faculty at Ribeirao Preto (HC-FRMP) in the Sao Paulo University, with the purpose to realize a quality control of the radiation dose supplied to blood bags. These dosemeters were divided in eight groups and irradiated for a two months period.The dosemeters were adhered to the bags and arranged inside of an acrylic box filled water with dimensions: (40x40x20) cm{sup 3}. The box irradiation was made using two fields parallel-opposed of (40x40) cm{sup 2} at 80 cm distance source-surface, in the Radiotherapy Service of HC-FMRP, with a {sup 60} Co teletherapy unit. The irradiation time was sufficient to supply a dose of 20 Gy approximately in the box center. The RPE measures were realized in a Varian E-4 spectrometer operating in X-band. For the total of dosemeters and for the irradiation volume, the minimum and maximum doses were of 14 Gy and 23 Gy respectively. The mean dose was (18{+-}2) Gy (1 {sigma}), and the variability coefficient 11 %. Around 5 % of the bags received a dose under of the recommended limit by the Brazilian legislation and as consequence, the exposure time was increased. (Author)

  4. Reconstructive dosimetry of radiological accidents - study of a brazilian case of industrial gamma radiography; Dosimetria reconstrutiva de acidentes radiologicos - estudo de um caso brasileiro de gamagrafia industrial

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Francisco Cesar Augusto da; Hunt, John G.; Ramalho, Adriana [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Pinto, Livia M.F. Amalfi [ARCtest - Servicos Tecnicos de Inspecao e Manutencao Industrial Ltda., Paulinia, SP (Brazil)]. E-mail: protecao@arctest.com.br

    2002-07-01

    On May 2000, an industrial gamma radiography operator, during a maintenance work of a {sup 60}Co irradiator, has suffered a radiological accident with severe consequences to the left hand. The experts of the High Doses Analysis Group (GADE/IRD/CNEN) initiated the reconstructive dosimetry for the radiation dose estimation, in order to determine the real dose received by the operator, and to help the medical evaluation for prescribing the medical procedures for treatment of the involved victim. This paper presents the reconstructive dosimetry performed through the determination of the radiation doses of the operator, based on theoretical, experimental and computational methods. For the computer methods, a program for the calculation of external doses were used, based on the Monte Carlo method, and a human body simulator composed by voxels. The values of effective and equivalent doses are also presented which has caused severe lesions on the operator hand.

  5. Experience on IMRT treatment for prostate cancer. Planning, dosimetry and quality assurance; Experiencia en el tratamiento de IMRT en cancer de prostata. Planificacion, dosimetria y garantia de calidad

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Barrado, A.; Garcia Vicente, F.; Fernandez Bedoya, V.; Zapatero Laborda, A.; Fernandez, I.; Bermudez Luna, R.; Perez Gonzalez, L.; Torres Escobar, J. J.

    2011-07-01

    In this study a revision concerning the treatment of prostate cancer with intensity-modulated radiation therapy (IMRT) is performed. Planning and verification of treatments involving dose calculations and image positioning are considered. A set of 110 patients is analysed concerning dosimetry and 92 considering image verification. Dose calculation is verified both experimentally and by means of a monitor unit (MU) calculation system. Positioning control of the prostate is achieved using intraprostatic fiducial markers and digitally reconstructed radiographs (DRRs) as well as a home-made software. All patients studied were consistent with the specifications of the treatment protocol regarding dose prescription in planning target volume (PTV), organ at risk (OAR) dose limitations, dosimetric quality assurance and positioning control. The procedure includes a learning curve considering every aspect of the treatment. The MU calculation system itself has been proved as an effective and functional tool for treatment verification. (Author) 12 refs.

  6. Dosimetry of internal emitting: principles and perspectives of the MIRD technology; Dosimetria de emisores internos: principios y perspectivas de la metodologia MIRD

    Energy Technology Data Exchange (ETDEWEB)

    Ferro F, G [Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, Salazar, Estado de Mexico C.P. 52045 (Mexico)

    1999-07-01

    The development of the radiopharmaceutical technology have multiplied the number of radioisotopes with applications in therapeutical nuclear medicine so known as Directed radiotherapy. Assuming the radiation is capable to produce noxious effects in the biological systems, it is important to evaluate appropriately the risks and benefits of the administration of radioactive agents in the patient. The outstanding parameter in this evaluation is the absorbed dose, which is product of the radiation emitted by a radionuclide that is localized or distributed to the interior of the human body in study and whose its estimation helps to predict the efficacy of the treatment. The scheme generalized of MIRD, it was formulated from thirty years ago for evaluating the interior dosimetry at level of organs.The finality of this work is to show the basic principles of the MIRD methodology and its perspectives using innovator tools as the dosimetry for dynamic masses, in particular the personnel dosimetry for the organs of each patient, the dosimetry for the small structures inside the organs (sub organic dosimetry), the distributions of doses in three dimensions (S voxel), the dosimetry at cellular level and the quantitative acquisition of pharmaceutical data. (Author)

  7. Direct detection of second harmonic and its use in alanine/EPR dosimetry; Deteccao direta do segundo harmonico e seu uso na dosimetria alanina/RPE

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Guzman, C.S.; Graeff, C.F.O.; Baffa, O. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica e Matematica]. E-mail: chen@dfm.ffclrp.usp.br

    2001-07-01

    In this work, the possible use of the second harmonic EPR signal from irradiated alanine for low radiation dose ({approx}1 Gy) was explored, aiming applications to HDR brachytherapy and teletherapy. The second harmonic signal was directly detected after overmodulation. A batch of DL-alanine/paraffin small cylindrical pellets was made. A VARIAN E-4 X-Band EPR spectrometer with optimized operation parameters like microwave power and modulation amplitude to obtain a signal with the highest amplitude was used. The modulation frequency and modulation amplitude were 100 kHz and 1.25 mT (to overmodulate the signal) respectively. The second harmonic signal was directly detected at twice the modulation frequency. One group of dosimeters was irradiated with a {sup 192} Ir brachytherapy source and the other in a 10 MeV X-rays linear accelerator, both group at a dose range: 0.5 - 15 Gy. The second harmonic signal showed better resolution than the first harmonic one making possible a more easy localization of the signal. Moreover, for both types of radiation, the dose-response curve showed a good linear behavior for the dose range indicated. (author)

  8. Annual course of retraining for the occupational exposure personnel of the laboratory of internal dosimetry; Curso anual de reentrenamiento para el POE del laboratorio de dosimetria interna

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2002-09-15

    The general objective of this report is to instruct the personnel in the basic concepts of radiological protection and in the Manual of Procedures of Radiological Safety of the Laboratory of Internal Dosimetry. Also, to exchange experiences during the activities that are carried out in the laboratory and in the knowledge of abnormal situations. The referred Manual consists of 14 procedures and 5 instructions which are listed in annex of this document. The content of this course consists of three topics: 1. Basic principles of radiological protection to reduce the received dose equivalent. 2. Use of radiation measurer equipment. 3. Emergency procedures of the laboratory of internal dosimetry. (Author)

  9. Thermoluminescent dosimetry in pediatric patients subjected to TAC cranium multi cutting studies; Dosimetria termoluminiscente en pacientes pediatricos sometidos a estudios de TAC multicorte de craneo

    Energy Technology Data Exchange (ETDEWEB)

    Tabares V, M.J.; Azorin N, J. [UAM-Iztapalapa, 09340 Mexico D.F. (Mexico); Azorin V, J.C. [CICATA-IPN, 11500 Mexico D.F. (Mexico)]. e-mail: azorin@xanum.uam. mx

    2007-07-01

    Full text: In this work the doses to critical organs in pediatric patient subjected to studies of multi cutting skull tomography were determined. The study included patient smaller than 16. The used tomograph was a Siemens Somaton 16 plus multi cutting. The dosimetry one carries out with thermoluminescent dosemeters of LiF:Mg,Cu,P +Ptfe of national production. This dosemeters type was used due to it characteristics, such as low fading, equivalence with the tissue, easy handling and reading and independence of it answer with the radiation energy. The value of the absorbed doses in organs in the simple study results half of the obtained value in the contrasted study that which indicates that the CTDI{sub vol} is proportional to the dose to organ. In the case of the skull three-dimensional reconstruction tomography the CTDI{sub vol} was practically the same one that for simple tomography was practically; however, the doses to organs differed significantly. When comparing the TDI{sub vol} value of the three-dimensional reconstruction tomography with that of the contrasted tomography the obtained reason it was 1:2; however, the doses to organ didn't show the same relationship and the absorbed dose in the case of the thyroid gland was even bigger in the study of three-dimensional reconstruction. The value of the CTDI{sub vol} is a good indicator of the exposure factors selected for the tomographic exploration and it is useful for the determination of the effective dose, but it doesn't indicate the absorbed dose to organ. (Author)

  10. Dosimetry of the JS-6500 industrial irradiator for the irradiation of the PVC graduated flasks; Dosimetria del irradiador industrial JS-6500 para la irradiacion de probetas de PVC

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda F, A.; Carrasco A, H.; Martinez P, M.E. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The dosimetry of the JS-6500 AECL irradiator was realized, outside of the industrial transportation rails to know the dose distribution, as well as its dose speed. This one with the intention of exposing to gamma radiation; plastified PVC graduated flasks and evaluating their interweavement or degradation or both. This study of dosimetry was carried out by means of a theoretical and experimental evaluation in air atmosphere. The results allow to know the irradiation conditions of the PVC graduated flasks as well as those results prove that has not a significant difference among the obtained result as theoretical as experimentally due to that the obtained result in the theoretical evaluation is 2.62 KGy/h and the result for the case of the experimental evaluation is 2.74 KGy/h. (Author)

  11. Applications of the Monte Carlo simulation in dosimetry and medical physics problems; Aplicaciones de la simulacion Monte Carlo en dosimetria y problemas de fisica medica

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E. L., E-mail: leticia.rojas@inin.gob.m [ININ, Gerencia de Ciencias Ambientales, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    At the present time the computers use to solve important problems extends to all the areas. These areas can be of social, economic, of engineering, of basic and applied science, etc. With and appropriate handling of computation programs and information can be carried out calculations and simulations of real models, to study them and to solve theoretical or application problems. The processes that contain random variables are susceptible of being approached with the Monte Carlo method. This is a numeric method that, thanks to the improvements in the processors of the computers, it can apply in many tasks more than what was made in the principles of their practical application (at the beginning of the decade of 1950). In this work the application of the Monte Carlo method will be approached in the simulation of the radiation interaction with the matter, to investigate dosimetric aspects of some problems that exist in the medical physics area. Also, contain an introduction about some historical data and some general concepts related with the Monte Carlo simulation are revised. (Author)

  12. Calibration of semiconductors diodes for in vivo dosimetry in total body irradiation treatments; Calibracao de diodos semicondutores para dosimetria in vivo em tratamentos de irradiacao de corpo inteiro

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Fernanda F.; Costa, Alessandro M.; Ghilardi Netto, Thomaz, E-mail: ferretti.oliveira@gmail.com [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias e Letras. Departamento de Fisica; Amaral, Leonardo L. [Universidade de Sao Paulo (HCFMRP/USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

    2012-08-15

    This paper presents the results of in vivo dosimetry with p-type semiconductors diodes, EDP-15 (Scanditronix Wellhoefer) of two patients who underwent total body irradiation treatments, at Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto University of Sao Paulo (HCFMRP-USP). The diodes were well calibrated and the calibration factors were determined with the aid of a reference ionization chamber (FC065, IBA dosimetry, sensitive volume of 0.65 cm{sup 3}).The calibration was performed in a Total Body Irradiation (TBI) setup, using solid water phantoms. Different lateral thicknesses from one patient were simulated and then the calibration factors were determined by means of maximum depth dose readings (half of the lateral thickness). The response difference between diode readings and the prescribed dose for both treatments was below 4%. This difference is in agreement as recommended by International Commission on Radiation Units (ICRU), which is {+-}5%. (author)

  13. Study of the reliability of the TLDs reader in a Thermoluminescent dosimetry laboratory; Estudio de la constancia de la lectora de TLDs en un laboratorio de dosimetria termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Silva F, J.C. da; Fonseca, H.G. da [Instituto de Radioprotecao e Dosimetria-IRD, Av. Salvador Allende s/n- CEP, 22780-160, Rio de Janeiro (Brazil)]. e-mail: Jfeital@ird.gov.br

    2006-07-01

    Acting from the beginning of the decade of 80 in a postal program called 'Dentistry Programs' the Institute of Radioprotection and Dosimetry (IRD) it makes an effort supported by the IAEA so that it can determine with security the reference levels for the diverse practices in radiodiagnostic, including the dentistry. The dentistry program that uses 4 TLDs of lithium fluorite (LiF 100) for evaluations of the doses and of the hemirreductor layer, until 1995 it had already verified close of 5529 X-ray equipment. This work accompanies the result of 3 main parameters (arbitrary reading, reference light and noise) of the reader Harshaw marks 5500, when it is used for routine readings of the TLDs that arrive in the dosimetry laboratory for the due ratings. Together with these TLDs 9 previously selected dosemeters of a certain dosemeters lot is placed with a percentage uncertainty of 3% (for 1 standard deviation). before them they were irradiated in an irradiator of Sr90/Y90 with a dose of approximately 5 mGy, they are treated thermally in an oven PTW it marks to 400 grades for 1 hour + 100 grades for 2 hours and 100 grades in 15 minutes after the irradiations. The referred methodology follows a procedure where they are distributed of 3 in 3 the chosen TLDs of the group of the 9, to the beginning, half and at the end among the total quantity of dosemeters read in the reading disk that it can read of a single time 50 dosemeters. Together with this 10 measurements of reference light and noise are made, data that are provided by the reader through the 'softer WinRem'. Finally the obtained results of reference light and noise, its are compared with the maker's recommendations. Already that of the arbitrary reading (average of the 9 TLDs and its uncertainties), it has revealed a reduction in the percentage uncertainty (2 deviations standard / average) with relationship to one of the first results already obtained through the methodology proposal. It has been, also, applied the statistical test (F of Snedecor) for the verification among the variance of the populations for these two samples. (Author)

  14. Dosimetry in Computed Tomography head and neck scans; Dosimetria em varreduras de Tomografia Computadorizada de cabeça e pescoço

    Energy Technology Data Exchange (ETDEWEB)

    Gómez, A.M.L.; Santana, P.C.; Mourão, A.P., E-mail: amlgphys@gmail.com [Universidade Federal de Minas Gerais (UFMG), Berlo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    Non-invasive diagnostic methods for X-rays, such as computed tomography (CT), have shown rapid growth in radiology services. There is concern about the radiation doses deposited in patients because the CT scans are the ones that contribute most to the dose increase in the population. The legislation for regulating patient dose levels only imposes an upper limit for a given test, depending on the region of the body to be irradiated. Therefore, it is necessary to know the dose values deposited in patients referring to routine protocols used in radiology services and propose an optimization of these according to the principles of radiological protection. Experiments were performed to determine the dose profile deposited in routine adult patient head scans using a male anthropomorphic simulator. Radiochromic film strips were introduced in the central region of the simulator to record the dose profile in the head and neck region and thus determine the air kerma values within the simulator object. Four scans were performed on a General Electric 64-channel tomograph programmed in helical mode and the scans were made with voltages of 80, 100 and 120 kV, and fixed current and automatic current control were used. The mean values recorded on the strips ranged from 14.82 to 22.98 mGy. Imaging noise analyzes were performed so that for all the scans the images obtained were considered of diagnostic quality and the Kerma values in the air when converted to absorbed dose are diagnostic parameters acceptable in the Brazilian legislation.

  15. Integrating techniques for neutron dosimetry in Linac 18 MV; Integrando tecnicas para dosimetria de neutrones en un Linac de 18 MV

    Energy Technology Data Exchange (ETDEWEB)

    Ceron R, P. V.; Diaz G, J. A. I.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico); Paredes G, L. C. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-10-15

    In this paper thermoluminescent dosimetry, analytical techniques and Monte Carlo calculations were used to estimate the neutron dose equivalent in a radiotherapy room with a linear electron accelerator of 18 MV. The equivalent dose was measured at isocenter to 1.42 m of target and at the entrance of the labyrinth of the room of a Novalis Tx. The neutron detectors were constructed with pairs of thermoluminescent dosimeters TLD 600 ({sup 6}LiF: Mg, Ti) and TLD 700 ({sup 7}LiF: Mg, Ti) which are placed inside a paraffin sphere of 20 cm in diameter. These measurements enabled the calculation of equivalent dose in the gate and the source term, using the relationships contained in the NCRP-151. Through the models carried out with the code MCNPX the absorbed dose distribution with regard to depth in a paraffin phantom are included and the neutron spectrum produced by the head, taking into account the geometry and component materials. The results are in the order of neutron milli sievert by gray of X-rays (mSv/Gy x) which are in the same order as those found in other reports for different accelerators. (Author)

  16. Electronic Paramagnetic Resonance of irradiated nails: challenges for a dosimetry in radiation accidents; Ressonancia Paramagnetica Eletronica de unhas irradiadas: desafios para uma dosimetria em acidentes radiologicos

    Energy Technology Data Exchange (ETDEWEB)

    Giannoni, Ricardo A., E-mail: giannoni@ird.gov.br [Instituto de Radioprotecao e Dosimetria, (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Rodrigues Junior, Orlando [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    The purpose of this work is to characterize samples of human nails exposed to high doses of radiation, applying the technique of Electron Paramagnetic Resonance (EPR). The objective is to establish a dose response study that allow determine the absorbed dose by exposed individuals in situations of radiological accidents, in a retrospective form. Samples of human nails were collected and afterward irradiated with gamma radiation, and received dose of 20 Gy. The EPR measurement performed on the samples, before irradiation, permitted the signal identification of the components associated with effects caused by the mechanical stress during the fingernail cutting, the so-called mechanically induced signal (MIS). After the irradiation, different species of free radicals were identified, the so-called radiation induced signal (RIS). (author)

  17. Use of semiconductor diodes for dosimetry TomoTherapy Hi-Art unit; Utilizacion de diodos de semiconductor para la dosimetria de una unidad Tomotherapy Hi-Art

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Rodriguez, J.; Garcia Repiso, S.; Martin Rincon, C.; Ramos Pacho, J. A.; Verde Velasco, J. M.; Montes Fuentes, C.; Dena Espinel, E. de; Gomez Llorente, P. L.; Fernandez Bordes, M.

    2011-07-01

    The radiotherapy unit TIT-Art TomoTherapy allows the realization of intensity modulated treatments in a helical manner through design, consisting of a linear accelerator installed on a rotating gantry in combination with the longitudinal movement of the treatment table and a multi leaf collimator (MLC) binary. The acceptance tests include, among other things, the acquisition of a set of dosimetric data (profiles and PDD), for later comparison with a reference set of measures taken at the factory, called the gold standard. Being pre commissioning from the factory, the unit will be accepted provided that the measured data meet the gold standard within preset tolerances. The dosimetric equipment used in the test of acceptance is provided by the manufacturer and so far is done with water tank, camera, software electrometer and associate of Standard Imaging and marketed by TomoTherapy Inc. The objective of this study is to compare the measures obtained with a semiconductor diode with the gold standard. (Author)

  18. Dosimetria de pacientes e médicos em intervenções coronárias percutâneas em Recife, Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    Maria do Socorro Rocha da Silva

    2011-04-01

    Full Text Available OBJETIVO: Este trabalho teve como objetivo estimar os valores de doses de radiação recebidas por médicos e pacientes em procedimentos intervencionistas cardíacos realizados em um hospital público na cidade de Recife, Pernambuco. MATERIAIS E MÉTODOS: As medidas foram determinadas em 31 pacientes adultos, dos quais 22 tiveram acompanhamento clínico após o procedimento, e em dois cardiologistas com mais de dez anos de experiência. Parâmetros de irradiação para cada procedimento foram registrados. RESULTADOS: Os valores obtidos para a dose absorvida máxima na pele do paciente variaram entre 612 e 8.642 mGy, sendo que 53% foram maiores que 2.000 mGy, valores estes que podem causar efeitos determinísticos. Com relação aos médicos, a dose efetiva média por procedimento foi de 11 µSv e os valores médios do equivalente de dose nas extremidades, mais altos, foram: 923 µSv no pé esquerdo, 514 µSv no pé direito, 382 µSv na mão esquerda e 150 µSv no olho esquerdo. Dependendo do número de procedimentos, as doses recebidas pelos médicos podem exceder os valores limites de doses estabelecidos pelas normas nacionais e internacionais. CONCLUSÃO: Os resultados obtidos sinalizam a necessidade de adoção de estratégias para otimização da proteção radiológica tanto de pacientes quanto de médicos.

  19. Dosimetry of ultraviolet radiation with BaHfO{sub 3} powders; Dosimetria de radiacion ultravioleta con polvos de BaHfO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Barrera A, A. A.; Aguilar D, G. A.; Guzman M, J.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Ceron R, V., E-mail: abalba1@hotmail.com [Universidad de Guanajuato, 37670 Leon, Guanajuato (Mexico)

    2016-10-15

    Ceramic materials based on pure barium hafnate (BaHfO{sub 3}) have been obtained as a powder by the co-precipitation method. The powders obtained have a cubic structure that favors the thermoluminescent and optical properties, through which a better detection of the non-ionizing radiation is allowed. With these powders various tests were performed in the ultraviolet range at different exposure times. These thermoluminescent (Tl) studies were carried out using a Tl 3500 hand held reader which yielded a brightness curve that ranged from room temperature to the 350 degrees Celsius. This BaHfO{sub 3} response exhibits a broad brightness curve with a single peak centered around 225 degrees Celsius. Finally, is reported that there are materials of barium hafnate (BaHfO{sub 3}) doped with some rare earths (Eu, Tb) which, instead of improving the performance of the powders, decrease it, so that the use of intrinsic barium hafnate is the most appropriate. (Author)

  20. Uncertainties in the dosemeter calibration used for dosimetry in mammography; Incertezas na calibração de dosímetros utilizados para dosimetria em mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Vivian C.R.N.; Evangelista, Claudete R.; Silva, Teógenes A. da, E-mail: vcrnb@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    This study aims to detail the sources of uncertainties and to estimate the combined standard uncertainties associated with the calibration procedure of dosimeters to be used in the dosimetry of X-ray bundles in mammography. A RADCAL ionization chamber, model RC6-M, and the semiconductor dosimeters UNFORS Xi and RADCAL Digitizer AGDM Accul-Gold were used. The calibration coefficients in terms of air kerma and uncertainties were obtained for the reference radiations of the W-Mo target-filter combinations. (author)

  1. Application of the Electron paramagnetic resonance to the ionizing radiation dosimetry; Aplicacion de la Resonancia paramagnetica electronica a la dosimetria de las radiaciones ionizantes

    Energy Technology Data Exchange (ETDEWEB)

    Urena N, F. [Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera Mexico-Toluca, 52045 Salazar, Estado de Mexico (Mexico)

    2000-07-01

    The Electron Paramagnetic Resonance (EPR) is defined as the resonant absorption of electromagnetic energy in paramagnetic substances by the spin transition of a non-pairing electron between different energy levels in presence of a magnetic field. (Slighter, 1989). One of the more important characteristic of EPR is that the electron spin levels are subdivided by the electron interaction with the magnetic dipoles of the nearby nucleus giving occasion for a spectral structure called hyperfine structure. In this kind of interactions two limit cases are distinguished: 1. when the non-pairing electron is located in a central ion surrounded of atoms belonging to coordinate molecules. 2. When a non-pairing electron interactioning in the same form with a number of equivalent nucleus, which is common in organic radicals, these will give as result spectra. Some EPR spectrometer can be used to dosimetric purposes by free radicals via. In this work, it is presented the application of EPR to dosimetry of ionizing radiations by free radicals via which allows to determinations of high doses. (Author)

  2. Analysis of the gamma criteria validation of dosimetric for VMAT; Analisis de los criterios gamma de validacion de dosimetrias para VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Carrasco, M.; Marti Asenjo, J.; Torres Pozas, S.; Madan Rodriguez, C.; Luque Japon, L.; Godoy Cazorla, J.; Martin Olica, R.

    2013-07-01

    The simultaneous use of the variable elements of the patients, make it necessary to add a specific quality control for each treatment in addition to the quality controls newspapers of the machine. Likewise, the absence of an international or academic standard that a procedure for the validation of these treatments, justify the study of possible criteria for validation. Mannequins and computer programs used in this respect support a variety of analytical methods for the validation of the reproduction of the treatment. These methods of analysis are evaluated according to their sensitivity and specificity. (Author)

  3. Dosimetric pens: evaluation of calibration results in the Laboratorio Nacional de Metrologia das Radiacoes Ionizantes do Instituto de Radioprotecao e Dosimetria (IRD/LNMRI), RJ, Brazil

    International Nuclear Information System (INIS)

    Quaresma, D.S.; Ramos, M.M.O.; Cabral, T.S.; Peixoto, J.G.P.

    2005-01-01

    Dosimetric pens are direct reading personal dosemeters that are used in the practices of radiation protection in industries, hospitals, universities, and research institutes in the country. Quality control of measurements made with these instruments must include their periodical calibration in one of the laboratories of the Calibration Laboratory Network for Ionizing Radiation with the aim to compare the behavior of the measurements made in dosimetric pens of different models and manufacturers, submitted for calibration in the LNMRI/IRD/CNEN (Brazilian Lab for Metrology of Ionizing Radiations of the Institute for Radioprotection and Dosimetry of the Brazilian Nuclear Energy Commission), RJ or national reference laboratory and a member of the Network, in the years of 2000 to 2002. The parameters considered for the purpose of this work were: accuracy and linearity of response and measurement uncertainty evaluated. The results show that among the analyzed models there are changes in behavior

  4. Electron dosimetry in irradiation processing with rad-hard diodes; Dosimetria de eletrons em processos de irradiacao com diodos resistentes a danos de radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Thais Cavalheri dos

    2012-07-01

    This work had the aim of the development of dosimetric systems based on Si special diodes, resistant to radiation damage to online monitoring of irradiation processing using 1.5 MeV electrons energy and for relative dosimetry and clinical electron beam scanning within an energy range of 6 MeV up to 21 MeV. The diodes used were produced by Float Zone standard (FZ), Magnetic Czochralski (MCz) and epitaxy growth (EPI) methods. In order to use the diodes as detectors, they were fixed on alumina base to allow the connection of the polarization electrodes and the signals extraction. After the diode assembly on the base, each one was housed in a black acrylic probe with aluminized Mylar Registered-Sign window and LEMO Registered-Sign connector. With the devices operating in photovoltaic mode, the integration of the current signals as a function of irradiation time allowed obtain the charge produced in the sensitive volume of each diode irradiated. The electron accelerator used for high doses irradiation was the DC 1500/25/4 JOB 188 of the 1.5 MeV installed at the Radiation Technology Center of the IPEN/CNEN-SP. The current profile as function of exposure time, the response repeatability, the sensitivity as function of absorbed dose and the dose response curve were studied for each device. In comparison to FZ diode, we observed a greater decrease in the sensitivity for MCz diode, and good repeatability in both cases. Also, the increasing of the charge with the absorbed dose was well fitted by a second order polynomial function. In the EPI diode characterization, this one exhibited repeatability better than CTA dosimeters applied routinely in radiation processing. The above results indicate the potential use of these radiation hardness Si diodes in online dosimetry to high doses applications. For low doses irradiation were used the linear accelerators KD2 and Primus, both manufactured by Siemens and located at Sirio-Libanes Hospital. The diodes responses were evaluated for electron beams within the energy range of 6 MeV up to 21 MeV. The following studies were carried out: the short-term repeatability, the dose-response curve as a function of absorbed dose, the charge sensitivity as function of electron beam energy, the percentage depth dose (PPD) and the dose transversal profile. Despite the response of the diodes FZ, MCz and EPI be slightly dependent on the electron beam energy, the dosimetric response was linear in all electron beam energy range studied. In addition to this, the EPI devices showed excellent agreement with simulation performed with Monte Carlo code and the measurements performed with MatriXX Registered-Sign , confirming that the devices can be used as dosimeters in radiotherapy for scanning purposes, dose distribution mapping, constancy monitoring of calibration factor and relative dosimetry. (author)

  5. Characterization of an electronic system for Image acquisition portal to open field dosimetry; Caracterizacao de um sistema eletronico de aquisicao de imagem portal para dosimetria em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Barbi, Gustavo L.; Oliveira, Harley F.; Bertucci, Edenyse C.; Amaral, Leonardo L.; Borges, Leandro F., E-mail: gustavobarbi@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas. Centro de Ciencias das Imagens e Fisica Medica

    2012-08-15

    The objective was to characterize and enable an electronic portal imaging device (EPID) to use like a portal dosimetry device - PDI, in non-transit mode, without interposition of scattering between the beam and EPID for measurement to open fields. The images as well as the DICOM header data are extracted from software ImageJ and the information are used in the basic algorithm for converting pixel to dose. The linearity and reproducibility of response were analyzed, and the maximum deviation found of 2,3% to 800 monitor units (MU) for linearity and -0,9% for reproducibility of signal measured daily. A 512x512 matrix with a resolution of 0,8mm was established to restore the shape of beam from the image. The field size dependence was evaluated, by obtaining the ratio of total scattering of ionization chamber and EPID. Finally, a calibration factor of 28470.88{+-}170.73 pixel/cGy was established for the central area of the image. Comparative analyzes between the PDI, radiochromic film and array of ionization chambers (MatriXX) showed good agreement for fields greater then 5 x 5 cm{sup 2} to reestablishment of form field and dose, however, for fields between 3x3 cm{sup 2} and 5x5 cm{sup 2}, the agreement to shape of beam was best established by film. (author)

  6. Obtention of a thermoluminescent material for dosimetry of ionizing radiation; Obtencion de un material termoluminiscente para dosimetria de la radiacion ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P R

    1990-07-01

    The thermoluminescent dosemeters are small crystals which suffer changes in their structure by the radiation effect, being displaced the electrons toward higher energy levels. On heating the previously irradiated crystals, the electrons come back to their base state emitting light photons. The light quantity emitted is proportional to the received radiation dose. The light quantity emitted is proportional to the received radiation dose. The lithium fluoride is one of the thermoluminescent materials considered as tissue equivalents by having a low effective atomic number (Z{sub ef}). At present, the more used commercial product used of this type is the TLD-100*. In this work the obtained results in the preparation of the lithium fluoride thermoluminescent material are presented. This is activated with magnesium (Mg) and titanium (Ti), which we have labelled as: LiF: Mg, Ti. The results from the tests performed for verifying his thermoluminescent properties are presented too, as powder form as in pellets form. These tests were performed in simultaneous form with TLD-100 samples, which is considered as reference. The LiF: Mg, Ti thermoluminescent material manufactured in the ININ presents similar dosimetric characteristics to those ones of the TLD-100. Therefore being able to replace the imported dosemeters. * (TLD-100 is a commercial trademark registered by Harshaw/Filtrol (US) for LiF: Mg, Ti Tl dosemeters) (Author)

  7. Thermoluminescent properties of ZrO{sub 2}:Mn for UV light dosimetry; Propiedades termoluminiscentes de ZrO{sub 2}:Mn para dosimetria de la luz UV

    Energy Technology Data Exchange (ETDEWEB)

    Rivera M, T. [Universidad Autonoma Metropolitana Iztapalapa, Deparatmento de Fisica, 09340 Mexico D.F. (Mexico); Azorin N, J. [CICATA-IPN, 11500 Mexico D.F. (Mexico); Falcony G, C. [CINVESTAV-IPN, Departamento de Fisica, 07300 Mexico D.F. (Mexico); Martinez, E.; Garcia, M. [Universidad Nacional Autonoma de Mexico, Instituto de Investigaciones en Materiales, 04510 Mexico D.F. (Mexico)

    1999-07-01

    The main source of ultraviolet light (UV) to whom is exposed the population is the one coming from the Sun, although exist some artificial sources too. The UV light can be classified in UV A (315-400)nm, in UV B (180-315) nm and UV C (100-180) nm. In this work are presented the results studying in the thermoluminescent characteristics of ZrO{sub 2}: Mn for the UV dosimetry. The studied dosimetric characteristics were: concentration effect of the doping material, erased thermal treatment, posterior thermal treatment to the irradiation, Tl curve, response in function to the wavelength, response in function to the dose and reproducibility. Finally, presenting results highly promisers for the UV light dosimetry. (Author)

  8. Electret ionization chamber: a new method for detection and dosimetry of thermal neutrons; Camara de ionizacao de eletretos: um novo metodo para deteccao e dosimetria de neutrons termicos

    Energy Technology Data Exchange (ETDEWEB)

    Ghilardi, A J.P.

    1988-12-31

    An electret ionization chamber with boron coated walls is presented as a new method for detecting thermal neutrons. The efficiency of electret ionization chambers with different wall materials for the external electrode was inferred from the results. Detection of slow neutrons with discrimination against the detection of {gamma}-rays and energetic neutrons was shown to depend on the selection of these materials. The charge stability over a long period of time and the charge decay owing to natural radiation were also studied. Numerical analysis was developed by the use of a micro-computer PC-XT. Both the experimental and numerical results show that the sensitivity of the electret ionization chamber for detection of thermal neutrons is comparable with that of the BF{sub 3} ionization chamber and that new technologies for deposition of the boron layer will produce higher efficiency detectors. (author). 102 refs, 32 fig, 10 tabs.

  9. Development of a calorimetric system for electron beam dosimetry in radiation processing; Desenvolvimento de um sistema calorimetrico para dosimetria de feixe de eletrons em processos por radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Banados P, H E

    1994-12-31

    A calorimetric system for electron beam dosimetry in radiation processing was developed. The system is composed of a graphite core calorimeter, the temperature measuring and electrical calibrating instrumentation, a microcomputer and the software for the system automation. The research aimed at the optimization of the project parameters, the development of advanced methodologies for calibrating the temperature sensor, the determination of the thermal capacity as a function of the temperature, the measurement of the absorbed dose, and the development of the software needed for the system operation. The operating range extends from 0.1 kGy to 30 kGy. The uncertainty in the measurement of the absorbed dose was estimated to be {+-} 1.8% at the 95% confidence level. Comparative tests of the absorbed dose measurements were made using the IPEN electron accelerator. The results obtained showed an excellent agreement between the absorbed dose determined by the calorimeter and the absorbed dose calculated from the nominal power delivered by the accelerator. (author). 67 refs, 63 figs, 2 tabs.

  10. Chromosomal analysis and application of biological dosimetry in two cases of apparent over exposure; Analisis cromosomico y aplicacion de la dosimetria biologica en dos casos de aparente sobreexposicion

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [Departamento de Biologia, ININ A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The gamma radiation calibration curve of {sup 60} Co is used which was generated in the ININ Laboratory of Biology to calculate the exposure dose of two workers whose dosemeters marked values above of the limit allowed. The analysis indicates that in a first case, the aberrations frequency corresponded to the basal value, therefore there is not over exposure. The aberrations frequency of the second case is lightly above to the basal value and therefore the probability favors to what the physical dosimetry indicates. (Author)

  11. Traceability of a panoramic gamma irradiator using different TLD systems as transfer Instruments; Trazabilidad de un irradiador panoramico mediante sistemas de dosimetria TL

    Energy Technology Data Exchange (ETDEWEB)

    Romero, A. M.; Saez, J. C

    1994-07-01

    This work shows the calibration in terms of the new operational radiological quantities Hp (10) and H(10) for different TLD systems (Harshaw TLD-100 and Panasonic UD-002) used in personal and environmental monitoring. The irradiations were performed in the Spanish Reference Laboratory in radiation protection levels, managed by the CIEMAT Metrology of ionizing radiations Unit. With those data, different calibrations of a panoramic gamma irradiator in terms of the radiological quantity for unit of time were established, providing the traceability of the irradiator to the Reference Laboratory using the corresponding TLD systems as transfer instruments. (Author) 9 refs.

  12. Traceability of a panoramic gamma irradiator using different TLD systems as transfer instruments; Trazabilidad de un irradiador panoramico mediante sistemas de dosimetria TL

    Energy Technology Data Exchange (ETDEWEB)

    Romero, A.M.; Saez, J.C.

    1994-08-01

    This work shows the calibration in terms of the new operational radiological quantities Hp(10) and H*(10) for different TLD systems (Harshaw TLD-100 and Panasonic UD-802) used in personal and environmental monitoring. The irradiations were performed in the Spanish Reference Laboratory in radiation protection levels, managed by the CIEMAT Metrology of ionizing radiations Unit. With these data, different calibrations of a panoramic gamma irradiator in terms of the radiological quantity for unit of time were established, providing the traceability of the irradiator to the Reference Laboratory using the corresponding TLD systems as transfer instruments. (Author) 9 refs.

  13. Dosimetry of the Occupational Exposure Personnel and not exposure of the INNSZ; Dosimetria del Personal Ocupacionalmente Expuesto (POE) y no expuesto del INNSZ

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz J, A [Departamento de Medicina Nuclear, Instituto nacional de la nutricion Salvador Zubiran, Mexico D.F. C.P. 14100 (Mexico)

    1999-07-01

    In this work, was measured the equivalent dose of all the personnel of Nuclear medicine and personnel of the Institute which by its activities remain in the Department, by time determined, through thermoluminescent dosemeters and the results were that the personnel presents variable equivalent dose and it is proportional to the time and radionuclide type which use for their work. By this it is allowed to secure what the work watched with respect to radiological protection to fulfil with the International Standards standing for personnel in the Institute. (Author)

  14. Precision of RL/OSL medical dosimetry with fiber-coupled Al2O3:C: Influence of readout delay and temperature variations

    DEFF Research Database (Denmark)

    Andersen, Claus Erik; Morgenthaler Edmund, Jens; Damkjær, Sidsel Marie Skov

    2010-01-01

    Carbon-doped aluminum oxide (Al2O3:C) crystals attached to 15 m optical fiber cables can be used for online in vivo dosimetry during, for example, remotely afterloaded brachytherapy. Radioluminescence (RL) is generated spontaneously in Al2O3:C during irradiation, and this scintillator-like signal...

  15. Estimation of equivalent dose and its uncertainty in the OSL SAR protocol when count numbers do not follow a Poisson distribution

    International Nuclear Information System (INIS)

    Bluszcz, Andrzej; Adamiec, Grzegorz; Heer, Aleksandra J.

    2015-01-01

    The current work focuses on the estimation of equivalent dose and its uncertainty using the single aliquot regenerative protocol in optically stimulated luminescence measurements. The authors show that the count numbers recorded with the use of photomultiplier tubes are well described by negative binomial distributions, different ones for background counts and photon induced counts. This fact is then exploited in pseudo-random count number generation and simulations of D e determination assuming a saturating exponential growth. A least squares fitting procedure is applied using different types of weights to determine whether the obtained D e 's and their error estimates are unbiased and accurate. A weighting procedure is suggested that leads to almost unbiased D e estimates. It is also shown that the assumption of Poisson distribution in D e estimation may lead to severe underestimation of the D e error. - Highlights: • Detailed analysis of statistics of count numbers in luminescence readers. • Generation of realistically scattered pseudo-random numbers of counts in luminescence measurements. • A practical guide for stringent analysis of D e values and errors assessment.

  16. Holocene climate dynamics and construction of the pesqueiras in the NW Iberian Lower Miño River: an OSL approach

    NARCIS (Netherlands)

    Viveen, W.; Sanjurjo-Sanchez, J.; Schoorl, J.M.; Veldkamp, A.

    2012-01-01

    Abstract In the Lower Miño River basin a 15-m thick sandy fluvial sequence is found at the town of Chan de Vide, some 55 km upstream from the Atlantic Ocean. The deposit is exceptional because it is the only known sandy deposit in the upstream reaches of the Lower Miño area, which is dominated by

  17. The loess sequence of Dolní Věstonice, Czech Republic: A new OSL-based chronology of the Last Climatic Cycle

    Czech Academy of Sciences Publication Activity Database

    Fuchs, M.; Kreutzer, S.; Rousseau, D.-D.; Antoine, P.; Hatté, Ch.; Lagroix, F.; Moine, O.; Gauthier, C.; Svoboda, Jiří; Lisá, Lenka

    2013-01-01

    Roč. 42, č. 3 (2013), s. 664-677 ISSN 0300-9483 Institutional support: RVO:67985831 ; RVO:68081758 Keywords : climate conditions * climate cycle * environmental change * loess * luminescence dating * magnetic susceptibility * oxygen isotope * paleoclimate * pedology * Pleistocene * quartz * regional climate * sedimentation rate * sedimentology * stratigraphy * transition zone Subject RIV: DB - Geology ; Mineralogy; AC - Archeology, Anthropology, Ethnology (ARUB-Q) OBOR OECD: Environmental sciences (social aspects to be 5.7); Archaeology (ARUB-Q) Impact factor: 2.383, year: 2013

  18. Testing single-grain quartz OSL methods using sediment samples with independent age control from the Bordes-Fitte rockshelter (Roches d'Abilly site, Central France)

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, Andrew Sean; Buylaert, Jan-Pieter

    2016-01-01

    We present quartz single-grain dose distributions for four well-bleached and unmixed sediment samples with independent age control (22–48 ka), from the archaeologically important Bordes-Fitte rockshelter at Roches d'Abilly, France. This site has previously been dated using 14C AMS dating and stan...

  19. Fine-grained quartz OSL dating chronology of loess sequence from southern Tajikistan: Implications for climate change in arid central Asia during MIS 2

    Science.gov (United States)

    Wang, Leibin; Jia, Jia; Li, Guoqiang; Li, Zaijun; Wang, Xin; Chen, Fahu

    2018-04-01

    The desert and semi-desert region of arid central Asia is one of the most important areas of middle-latitude dust emission and deposition in the Northern Hemisphere. Marine isotope stage 2 (MIS 2) was the latest and one of the most representative intervals of dust emission from the region, and it is especially important for research into processes of dust transportation and deposition. Here, we report the results of an optically stimulated luminescence study of the Hoalin section in southern Tajikistan, which was deposited during MIS 2. The fine-grained quartz single aliquot regeneration (SAR) approach was used and its reliability was verified by internal checks. In addition, grain-size analyses, calculated dust accumulation rates (DARs) and mass accumulation rates (MARs) were used to reconstruct the pattern of climate change during MIS 2. The mean DAR for southern Tajikistan during MIS 2 was 0.43 m/ka, and the corresponding average MAR was 673 g/cm2/a for a non-river-terrace site, which is higher than the average MARs estimated for the central and southern Chinese Loess Plateau (CLP). In contrast to previous suggestions, the high dust DARs and MARs during the LGM indicate a 'cold-dry' climatic pattern, rather than a 'cold-humid' pattern. Our results also confirm that the patterns of high dust emission and deposition during the LGM in the mid-latitude arid zone of Asia were synchronous.

  20. Evaluation of the processes used for the treatment of the hospitable radwastes containing Cs-137

    International Nuclear Information System (INIS)

    Peres, S.S.; Silva, J.J.G.

    1988-01-01

    This work presents a resume of results obtained in the treatment of radwastes containing Cs-137 from HNMD (Hospital Naval Marcilio Dias) and IRD (Instituto de Radioprotecao e Dosimetria), due to the radiological accident of Goiania. (author) [pt

  1. Development of optically stimulated luminescence reader systems in BARC

    International Nuclear Information System (INIS)

    Kulkarni, M.S.

    2008-01-01

    BARC has very vast experience in the development of thermoluminescence (TL) reader systems both for routine personnel monitoring and research application. However, optically stimulated luminescence (OSL) related instrumentation is a recent development in BARC. The increasing popularity of OSL technique in the radiation dosimetry applications in the recent past has driven investigation and developmental programme in the OSL measurement facilities at BARC. As the consequence of the efforts directed towards the indigenous development of OSL reader system, OSL readers with various readout modes like continuous wave (CW) OSL mode, linear intensity modulated OSL (LM-OSL), pulsed OSL (POSL) have been developed. In addition to these conventional modes of operation a novel non-linear OSL mode (NL-OSL) has also been developed for the OSL measurements. This paper reviews the details of the development of OSL reader system including experience with high intensity blue/green LED stimulation light source and detection system. Also discussed are recently developed versatile integrated TL/OSL reader systems for TL and OSL measurements. (author)

  2. Biokinetics and dosimetry in patients of {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesin: images of GRP receptors; Biocinetica y dosimetria en humanos de {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesina: imagenes de receptores GRP

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C L [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2007-07-01

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [{sup 99m}Tc]EDDA/HYNIC-Lys{sup 3}-bombesin ({sup 99m}Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red marrow). The mean effective dose was 3.3 +- 0.6 mSv. Conclusions: The highest absorbed dose variability was found in breast tissues because of differences in the in vivo affinity for GRP-r over-expression. All the absorbed doses are comparable with that known for most of the {sup 99m}Tc studies. In spite of the ubiquitous GRP-r expression in non-neoplastic tissues {sup 99m}Tc-HYNIC-BN is as a promising imaging radiopharmaceutical to target site-specific early breast cancer. These results warrant a further clinical study. (Author)

  3. Internal dose assessment in nuclear medicine: fetal doses due to radiopharmaceutical administration to the mother; Dosimetria interna en medicina nuclear: dosis absorbida en el feto por la administracion de radiofarmacos a la madre

    Energy Technology Data Exchange (ETDEWEB)

    Rojo, Ana M; Michelin, Severino C

    2004-07-01

    The objective of this publication is to present a guideline for the dose assessment through a comprehensive introduction of knowledge on ionizing radiation, radiation protection during pregnancy and fetal dosimetry for physician and other professionals involved in nuclear medicine practices. It contains tables with recommended dose estimates at all stages of pregnancy for many radiopharmaceuticals. Compounds for which some information was available regarding placental crossover are shown in shaded rows. It includes the most common diagnostic and therapy practices in nuclear medicine considering the four radioactive isotopes selected: {sup 99m}Tc, {sup 131}I, {sup 201}Tl and {sup 67}Ga. There is a special case included, it is when conception occurs after the iodine has been administered. In almost every case, the diagnostic benefit to the mother outweighs the risk of any irradiation of the fetus. However, there is one situation in which severe fetal injury can be incurred from administering a radiopharmaceutical to the mother, and that is use of iodine-131 therapy for ablation of the thyroid in cases of hyperthyroidism or carcinoma. Radioactive iodine readily crosses the placenta and concentrates in the fetal thyroid, where, because of its small organ mass, high radiation doses are received. (author)

  4. Radiological protection in pelvis studies by computed tomography in Rando phantom by means of thermoluminescent dosimetry; Proteccion radiologica en estudios de pelvis por tomografia computada en fantoma Rando mediante dosimetria termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Madrid G, O. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Calz. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin N, J., E-mail: riveramt@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2011-11-15

    The risks of the radiation in computed tomography (CT) studies have been recently reported in many works. Caution should be had in the environment of the exploration in the patient. To maintain the radiation doses so low as is reasonably possible during the CT examination, is important that in the CT the parameters are correctly adjusted for each patient with the purpose of having the minimum dose in the application of the study. Thermoluminescent dosimeters were used to measure the absorbed dose and to measure the CT profiles of dose. The distribution of the dose in the CT abdominal examination in the simulated patients was evaluated. The exploration parameters of the CT were 130 kV, 90 m A, with a cut thickness of 3 mm and a field of 1.0 in the pitch. The assignment dose was increased in an axis along the direction of the study, they were also studied. The equivalent dose due to the direct and dispersed radiation was determined during the procedures of the irradiation in pelvis examinations, for the next areas to the study like is in specific the critical organ (gonads) that is the terminal area of the exploration. During this study of 26 cuts was obtained an equivalent dose to critical organ of 14.27 mSv. (Author)

  5. Neutron spectrometry and dosimetry with neural networks and Bonner spheres: a study to reduce the spheres number; Espectrometria y dosimetria neutronica con redes neuronales y esferas Bonner: un estudio para reducir el numero de esferas

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza G, J. G.; Martinez B, M. R.; Leon P, A. A.; Hernandez P, C. F.; Castaneda M, V. H.; Solis S, L. O.; Castaneda M, R.; Ortiz R, J. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Av. Ramon Lopez Velarde 801, Col. Centro, 98000 Zacatecas, Zac. (Mexico); Mendez, R. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Laboratorio de Patrones Neutronicos, Av. Complutense 22, 28040 Madrid (Spain); Gallego, E. [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, C. Jose Gutierrez Abascal 2, 28006 Madrid (Spain); De Sousa L, M. A. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, MG (Brazil)

    2016-10-15

    For neutron spectrometry and neutron dosimetry, the Bonner spheres spectrometric system has been the most widely used system, however, the number, size and weight of the spheres composing the system, as well as the need to use a reconstruction code and the long periods of time used to carry out the measurements are some of the disadvantages of this system. For the reconstruction of the spectra, different techniques such as artificial neural networks of reverse propagation have been used. The objective of this work was to reduce the number of Bonner spheres and to use counting speeds in a reverse propagation neural network, optimized by means of the robust design methodology, to reconstruct the neutron spectra. For the design of the neural network we used the neutron spectra of the IAEA and the response matrix of the Bonner spheres with {sup 6}LiI(Eu) detector. The performance of the network was compared; using 7 Bonner spheres against other cases where only 2 and one sphere are used. The network topologies were trained 36 times for each case keeping constant the objective error (1E(-3)), the training algorithm was trains cg and the robust design methodology to determine the best network architectures. With these, the best and worst results were compared. The results obtained using 7 spheres were similar to those with the 5-in sphere, however is still in an information analysis stage. (Author)

  6. Accreditation of the Personal Dosimetry internal Service Tecnatom by the National Entity (ENAC); Acreditacion del Servicio de Dosimetria Personal Interna de Tecnatom por la Entidad Nacional de Acreditacion (ENAC)

    Energy Technology Data Exchange (ETDEWEB)

    Bravo, B.; Marchena, P.

    2014-07-01

    The service of personal Dosimetry internal Tecnatom has made the process of adapting its methodology and quality assurance, requirements technical and management will be required to obtain accreditation from the National Accreditation Entity according to ISO / IEC 170251 standard {sup G}eneral Requirements competence of testing and calibration laboratories. To carry out this process, the laboratory has defined quality criteria set out in their test procedures, based on ISO Standards 27048: 2011; ISO 20553: 2005 and ISO 28218: 2010. This paper describes what has been the methodology used to implement the requirements of different ISO test methods of SDPI Tecnatom. (Author)

  7. Internal dosimetry for the radiological protection of the patient in the therapy with I-131; Dosimetria interna para la proteccion radiologica del paciente en la terapia con I-131

    Energy Technology Data Exchange (ETDEWEB)

    Deluca, G.M.; Rojo, A.M. [Autoridad Regulatoria Nuclear, Av. Del Libertador 8250 (C1429BNP), Buenos Aires (Argentina)]. e-mail: gdeluca@cae.arn.gov.ar

    2006-07-01

    In the patients with differentiated thyroid cancer (CADIT) subjected to therapy with radiopharmaceuticals should be considered the possible risk of sharp depression of the bone marrow like consequence of the intolerance to the quantity of administered activity. The manifestation of the myelotoxicity can limit in a substantial way the future treatments and to deteriorate the predict of resolution of the illness. In this work it shows the physical-mathematical mark of a methodology for the estimated absorbed dose in bone marrow based in the MIRD scheme whose objective is to protect the one patient of the noxious and undesirable effects of the internal radiotherapy in organs that are not target of the same one. The formalism incorporates specific information of the patient and also peculiar characteristics of the internal therapy in patient with CADIT. The considerations are the following ones: (1) the main organ to protect is the bone marrow: (2) the accumulated activity, in bone marrow, it is obtained starting from measurements in blood: (3) the used isotope almost exclusively in this type of therapies is the {sup 131}I; (4) it is used as radiopharmaceutical at the {sup 131}INa that it is characterized to be a simple, inorganic and small molecule: (5) the statistical incidence of the CADIT is bigger in women than in men. It is explained for that it was selected the formalism that is presented, the principles on which it is sustained which are their reaches and their limitations. They are also presented future innovations that can be implemented to effects of improving the estimates. The work is framed inside the thematic of the medical applications of open radioactive sources and it constitutes a contribution to the invigoration of the internal therapy with radiopharmaceuticals. This is due to that the methodology of dose estimation presented supplements with a theoretical biophysics base the protocols of empiric prescription broadly used in this practice. For these reasons, the dosimetric information obtained, adjusted to each concrete case, it contributes to improve the radiological protection of the patient. (Author)

  8. Reshaping of computational system for dosimetry in neutron and photons radiotherapy based in stochastic methods - SISCODES; Remodelagem do sistema computacional para dosimetria em radioterapia por neutrons e fotons baseado em metodos estocasticos - SISCODES

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Bruno Machado

    2011-02-15

    This work shows the remodeling of the Computer System for Dosimetry of Neutrons and Photons in Radiotherapy Based on Stochastic Methods . SISCODES. The initial description and status, the alterations and expansions (proposed and concluded), and the latest system development status are shown. The SISCODES is a system that allows the execution of a 3D computational planning in radiation therapy, based on MCNP5 nuclear particle transport code. The SISCODES provides tools to build a patient's voxels model, to define a treatment planning, to simulate this planning, and to view the results of the simulation. The SISCODES implements a database of tissues, sources and nuclear data and an interface to access then. The graphical SISCODES modules were rewritten or were implemented using C++ language and GTKmm library. Studies about dose deviations were performed simulating a homogeneous water phantom as analogue of the human body in radiotherapy planning and a heterogeneous voxel phantom, pointing out possible dose miscalculations. The Soft-RT and PROPLAN computer codes that do interface with SISCODES are described. A set of voxels models created on the SISCODES are presented with its respective sizes and resolutions. To demonstrate the use of SISCODES, examples of radiation therapy and dosimetry simulations for prostate and heart are shown. Three protocols were simulated on the heart voxel model: Sm-153 filled balloon and P-32 stent, to prevent angioplasty restenosis; and Tl-201 myocardial perfusion, to imaging. Teletherapy with 6MV and 15MV beams were simulated to the prostate, and brachytherapy with I-125 seeds. The results of these simulations are shown on isodose curves and on dose-volume histograms. The SISCODES shows to be a useful tool for research of new radiation therapy treatments and, in future, can also be useful in medical practice. At the end, future improvements are proposed. I hope this work can contribute to develop more effective radiation therapy treatments. (author)

  9. Fabrication and electrical characterization of polyaniline-silicon heterojunction for gamma radiation dosimetry application; Fabricacao e caracterizacao eletrica de heterojuncoes de polianilina - silicio para aplicacao em dosimetria de radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Laranjeira, Jane Maria Goncalves

    2004-08-15

    In this work a technique has been developed to fabricate high quality polyaniline-silicon heterojunction diodes for use as gas and/or ionizing radiation sensors. Polyaniline thin films (40 nm thick) produced by spin-coating on silicon substrates, were the active part of the junction structure. The devices presented excellent reproducibility of their electrical characteristics with high rectification ratio, 60,000 at {+-}1.0 V, and typical reverse current at - 1.0 V of 3 nA at 295 K. A G/I x G plot has been used to analyze the current-voltage characteristics, yielding typical series resistance of 4 k{omega} {+-} 5% and ideality factor in a range of 1,9 {+-} 0.5%. The heterojunction diode presents high sensitivity to gamma radiation in the dose range of 3 x 10{sup -2} to 7 kGy with a linear response in the forward and reverse bias. The excellent electrical characteristics together with the linear response with the dose, strongly suggest the application of this device for spectrometry or dosimetry of high doses of gamma radiation. These devices presented high sensitivity to gas moistures such as ammonia, nitric acid and trichloroethylene. In both cases the sensitivity was observed through shifts of the current-voltage curves, which can be easily monitored to provide a calibration curve of the sensor either as a radiation dosimeter or as a gas sensor for use in applications for gas monitoring or radiation dosimetry. Several aspects of the reliability physics of silicon-polyaniline heterojunction, such as degradation effects induced by local heating, charge trapping and temperature changes, have been discussed. These results further confirm the quality of the devices electrical characteristics and their suitability for radiation and gas sensors applications. Another interesting results presented in this work was the use of polyemeraldine nanofilms (thickness in the range 30-50 nm) deposited by 'spin coating' on glass substrates as an optical dosimeter for gamma radiation based on the color change of the polymer. The nanofilms devices were characterized by UV visible absorption spectroscopy. The deep blue color, characteristic of undoped polyaniline films before irradiation, becomes subsequently green as the film is being irradiated, and the film absorption coefficient exhibits a linear dependence with the logarithm of the irradiation dose from I to 10 kGy. (author)

  10. Calculation of the uncertainty of H{sub P} (10) evaluation for a thermoluminescent dosimetry system; Calculo da incerteza da avaliacao do H{sub P} (10) para um sistema de dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, M.S.; Silva, E.R.; Mauricio, C.L.P., E-mail: max.das.ferreira@gmail.com [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    Full interpretation of dose assessment only can be performed when the uncertainty of the measurement is known. The aim of this study is to calculate the uncertainty of the TL dosimetry system of the LDF/IRD for evaluation of H{sub P} (10) for photons. It has been done by experimental measurements, extraction of information from documents and calculation of uncertainties based on ISO GUM. Energy and angular dependence is the most important source to the combined u{sub c}(y) and expanded (U) uncertainty. For 10 mSv, it was obtained u{sub c}(y) = 1,99 mSv and U = 3,98 mSv for 95% of coverage interval. (author)

  11. TL dosimetry in the new Tandetron ion accelerator site of the National Institute of Nuclear Research (ININ); Dosimetria TL en el area del nuevo acelerador de iones Tandetron del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valdovinos A, M.; Gonzalez M, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The National Institute of Nuclear Research (ININ) acquired a positive ions accelerator type Tandetron 2 MV of the dutch company High Voltage Engineering, Europe B.V., which was finished its installation this year (2000) in an already existing building in the Dr. Nabor Carrillo Flores Nuclear Centre, where it was prepared for the following purposes: the accelerator will be used to realize research through X-ray emission induced by charged particles, Rutherford backscattering analysis, nuclear reaction analysis, gamma ray emission induced by charged particles, resonant dispersion analysis, elastic backward detection analysis and by particle canalization analysis. The accelerator consists of an injection system with two ion sources, ion accelerator tank with voltage in terminal at 2 MV, recovery and recirculation system of charge interchange gas, iman selector analyzer system and with high energy focussing, control system through computer and management and recovery of isolator gas system. For the realization of operation tests of this accelerator, it was had the license authorizing by the National Commission of Nuclear Safety and Safeguards (CNSNS). During the test stage Tl dosemeters were arranged in the Tandetron accelerator area, and also in direction to the beam outlet. In this work, are presented the obtained results of the measurement of radiation levels, as in the area as in the beam outlet. (Author)

  12. Secondary calibration laboratory for dosimetry in levels of therapy at the University of Santiago; Laboratorio secundario de calibracion para dosimetria en niveles de terapia en la Universidad de Santiago

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Rodriguez, F.; Gonzalez Castano, D. M.; Pazos Alvarez, A.

    2011-07-01

    A basic inherent benefits provided by the existence of a traceability chain radiation in any application, add the legal requirement for hospitals as pointed to by the RO. 1566/1998, which sets quality standards in radiotherapy. The decree attributed to hospital specialists radio physics in article 10 the responsibility for determining the acceptance and initial reference state of radiation generating equipment for therapeutic purposes, and the establishment and implementation of quality control programs associated and technical and physical aspects of radiation dosimetry. Different international organizations such as ICRU and IAEA recommendations on maintaining the accuracy of the dose delivered to patients in general, should be placed at least 5% considering the whole chain irradiation. In order to achieve this purpose it is necessary to establish programs of quality control and calibration dosimetric regular basis. The protocol of the IAEA TRS398 recommended dose calibration in water because it is a quantity of interest closest to clinical use and allows a relative uncertainty in the calibration environment reduced to 1%.. (Author)

  13. Dosimetry on ocular brachytherapy with ROPES plaque with Iodine-125 and Palladium-103 seeds; Dosimetria em braquiterapia ocular com placa ROPES contendo sementes de iodo-125 e paladium-103

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, Arnaldo P. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET/MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar], e-mail: aprata@des.cefetmg.br; Campos, Tarcisio P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares

    2010-03-15

    Radiotherapy is an alternative to ocular enucleation. However, the irradiation of ocular region can bring deleterious effects due to the high doses, mainly in the lens, retina and in the bone structures in growth phase. Brachytherapy instead of teletherapy looks for departuring absorbed doses in tumor minimizing doses in the lens and the adjacent tissues of the eyeball (orbital region), avoiding deleterious effects. Thus, a three-dimensional computational model of ocular area was developed to simulate orbital irradiation with ROPES ophthalmologic plaque placed on the sclera surface filled to ten iodine-125 seeds, and palladium-103 seeds. Simulations are performed on the MCNP5 code. The computational simulation allows evaluating how the dose rates are spatially distributed in the orbital volume. The results are normalized to 100% at the maximum dose on the tumor base, and by the applied source activity. The maximum dose is found onto the eyeball, in the vitreous. The present model represents an advance in simulating and predicting absorbed dose on ocular brachytherapy. (author)

  14. Dosimetry on ocular brachytherapy with ROPE plaque with iodine{sub 1}25 and palladium-103;Dosimetria em braquiterapia ocular com placa ROPES contando sementes de iodo-125 e paladio-103

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, Arnaldo P. [Centro Federal de Educacao Tecnologica (CEFET/MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar; Campos, Tarcisio [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares

    2009-07-01

    Radiotherapy is an alternative to ocular enucleation. However, the irradiation of ocular region can bring deleterious effects due to the high doses, mainly in the lens, retina and in the bone structures in growth phase. Brachytherapy instead of teletherapy looks for departing absorbed doses in tumor minimizing doses in the lens and the adjacent tissues of the eyeball (orbital region), avoiding deleterious effects. Thus, a three-dimensional computational model of ocular area was developed to simulate orbital irradiation with ROPES ophthalmologic plaque placed on the sclera surface filled to ten iodine-125 seeds, and palladium-103 seeds. Simulations are performed on the MCNP5 code. The computational simulation allows evaluating how the dose rates are spatially distributed in the orbital volume. The results are normalized to 100% at the maximum dose on the tumor base, and by the applied source activity. The maximum dose is found onto the eyeball, in the vitreous. The present model represents an advance in simulating and predicting absorbed dose on ocular brachytherapy. (author)

  15. Synthesis and characterization of alanine boron hydrate for its use in thermal neutron dosimetry.; Sintesis y caracterizacion del borohidrato de alanina para su uso en dosimetria de neutrones termicos.

    Energy Technology Data Exchange (ETDEWEB)

    Yanez S, J C

    1994-07-01

    Alanine boron hydrate was synthesized for its possible use as intercomparison dosimeter for thermal neutron irradiation. The irradiations were performed in the Nuclear Reactor of the Nuclear Center of Mexico. The salt was prepared by reacting alanine and boric acid in a (1:1) stoichiometric ratio in neutral pH 7.5 aqueous solution and also in a basic pH 13 solution. The latter reaction was prepared with the addition of ammonia hydroxide (25%). Solutions were stirred and afterwards were let to evaporate. The obtained product in each reaction is a white solid. Dosimeters were prepared with the obtained reaction products and irradiated under thermal neutron flux of 5 x 10{sup 7} n/cm{sup 2} s. For 30 hours. The analysis of irradiated samples was made in a Variant E-15 Electron Paramagnetic Resonance spectrometer. The observed response of the samples prepared with the reaction product at the basic pH is approximately 50% higher than the neutral pH samples. In order to investigate the optimum signal enhancement samples were prepared in a basic pH medium in the following stoichiometric ratios: (1:0.5); (1:0.75); (1:1.25); (1:1.5) and (1:1.75). It was observed that the samples of the reaction (1:0.75) produced the higher response. The response was 2728% higher than the alanine only dosimeters. The reaction product was chemically characterized by X-ray diffraction, Nuclear Magnetic Resonance, Chromatography, Refractometry and Solubility tests. Results indicate that alanine boron hydrate is formed in basic media and in a stoichiometric ratio (1:0.75). The dosimetric characterization of alanine boron hydrate was performed, results are reported. It is concluded that alanine boron hydrate may be a good intercomparison dosimeter for thermal neutron irradiation. (Author).

  16. Development of internal dosimetry protocols using the code MCNPx and voxelized phantoms of Reference of ICRP 110; Desenvolvimento de protocolos de dosimetria interna empregando o codigo MCNPx e fantomas voxelizados de referencia da ICRP 110

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, B.M.; Fonseca, T.C.F., E-mail: bmm@cdtn.br [Centro de esenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Trindade, B.M.; Campos, T.P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-04-01

    The objective of this work was to perform internal dosimetry calculations for {sup 18}F-FDG employing the MCNPx code and ICRP 110 voxelized reference phantoms (RCP{sub A}F and RCP{sub A}M). The methodologies developed and validated here represent protocols of internal dosimetry holding a better anthropomorphic and anthropometric representation of the human model in which heterogeneous distributions of the emissions can be adopted, useful in the study of new radiopharmaceuticals and internal contamination cases. The reference phantoms were implemented to run on MCNPx. Biodistribution data of {sup 18}F-FDG radiopharmaceutical provided in ICRP 128 were used in the simulations. The organs average absorbed doses and the effective doses were calculated for each model. The values obtained were compared with two reference works available in the literature for validation purposes. The means of the difference of our values and Zankl et al., 2012 reference values were -0.3% for RCP{sub A}M and -0.4% for RCP{sub A}F. Considering Hadid et al., 2013 reference values, the means of the deviation were -2.9% and -2.2% for RCP{sub A}M and RCP{sub A}F respectively. No statistically significant differences were observed (p <0.01) between the reference values and the values calculated by the internal dosimetry protocols developed by our group. Considering the {sup 18}F-FDG validation study performed in this work, the internal dosimetry protocols developed by our group have produced suitable dosimetry data. (author)

  17. Subsidies to cytogenetic dosimetry technique generated from analysis of results of Goiania radiological accident; Subsidios a tecnica de dosimetria citogenetica gerados a partir da analise de resultados obtidos com o acidente radiologico de Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Adriana Teixeira

    1993-06-15

    Following the Goiania radiation accident, which occurred in September of 1987, peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequency of unstable chromosomal aberrations (dicentrics and centric rings) to estimate absorbed radiation dose. During the emergency period, the doses were assessed to help immediate medical treatment. After this initial estimation, doses were reassessed using in vitro calibration curves produced after the accident, more suitable for the conditions prevailing in Goiania. Dose estimates for 24 subjects exceeded 0,5 Gy. Among those, 15 individuals exceeded 1,0 Gy and 5 exceeded 3,0 Gy. None of the estimates exceeded 6,0 Gy. Four of the subjects died. During the emergency period, a cytogenetic follow-up of 14 of the exposed patients was started, aiming to observe the mean lifetime of lymphocytes containing dicentric and ring aberrations. The results suggest that for the highly exposed individuals the disappearance rate of unstable aberrations follows a two- term exponential function. Up to 470 days after the exposure, there is a rapid fall in the aberration frequency. After 470 days, the disappearance rate is very slow, almost constant. The estimated average half-time of elimination of dicentrics and rings among the highly exposed group (> 1 Gy) was 140 days for the initial period after the exposure (up to 470 days). This value is significantly shorter than the usually accepted value of 3 years reported in the literature. Mean disappearance functions of unstable chromosome aberrations were inferred, to be applied in accident situations in which there is a blood sampling delay. Statistical analysis of possible correlations between the individual half-times and biological parameters, such as sex, age, leukopenia level shown during the critical period, absorbed dose (initial frequency of chromosomal aberrations) and the administration of the bone marrow stimulating factor (rHuGM-CSF) was performed. None of these parameters showed correlation to the half-time of disappearance of chromosomal aberrations. For one patient who had high {sup 137}Cs body burden, the aberration yield at first increased in reasonable agreement with the estimated doses due to internal contamination, and later began to fall following the decorporation of {sup 137}Cs.

  18. Development of a dosimetric system for {sup 90}Sr + {sup 90}Y betatherapy applicators; Desenvolvimento de um sistema de dosimetria para aplicadores de betaterapia de {sup 90}Sr + {sup 90}Y

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Talita Salles

    2010-07-01

    The {sup 90}Sr+{sup 90}Y applicators, used in betatherapy for prevention of keloids and pterigium, are imported and many times their dosimetric features are shown only in an illustrated form by the manufacturers. The exhaustive routine of the medical physicists in the clinic do not make possible the accomplishment of procedures for the confirmation of these parameters. This work presents the development of a methodology for the dosimetry of {sup 90}Sr+{sup 90}Y betatherapy applicators. The Monte Carlo code MCNP5 was used for the simulation of the percentage depth dose curves and dose distribution profiles produced by these applicators. The experimental measurements of the radial and axial radiation attenuation, have been done with a mini-extrapolation chamber, thermoluminescent dosimeters and radiographic films. The experimental results have been compared with the simulated values. Both percentage depth dose curves and the radial dose profiles, the theoretical and the experimental ones, have presented good agreement, which may validate the use of the MCNP5 for these simulations, confirming the viability of the usage of this method in procedures of beta emitter sources dosimetry. (author)

  19. Influence of the modification of protocol internal of change of dosimeters in the personal dosimetry control; Influencia de la modificacion del protocolo internao de cambio de dosimetros en el control de la dosimetria personal

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, M. A.; Ramirez Ros, J. c.; Lobat Munoz, M.; Jodar Lopez, C. A.; Jerez Sainz, M. I.; Pamos Urena, M.; Carrasco Rodriguez, J. L.

    2013-07-01

    The linking of the correct use of the dosimeter with economical remuneration received by the worker is very useful, since it has allowed us to lower the number of assignments of administrative, due to various incidents doses, as they are not repeated shipments, lost dosimeters or anomalous readings. (Author)

  20. Evaluation of radiochromic films EBT3 for in-vivo dosimetry in radiotherapy treatments with photons; Evaluacion de peliculas radiocromicas EBT3 para dosimetria in vivo en tratamientos de radioterapia con fotones

    Energy Technology Data Exchange (ETDEWEB)

    Galvan de la C, O. O.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Garcia G, O. A.; Larraga G, J. M., E-mail: olinca@ciencias.unam.mx [Instituto Nacional de Neurologia y Neurocirugia, Laboratorio de Fisica Medica, Insurgentes Sur 3877, Col. La Fama, 14269 Mexico D. F. (Mexico)

    2015-10-15

    Full text: In-vivo dosimetry is a challenge in radiotherapy due to the measures are carried out in reference conditions outside; there is no balance of charged particle and beam consists of photons own and contamination electrons. Detectors that are useful for such measures should be sufficiently small and thin so they do not disturb the beam and do not alter the dose on target. In this paper the radiochromic films Gafchromic model EBT3 are evaluated as potential detectors for in-vivo dosimetry; measurements were carried out in solid water phantom on the surface, with films of dimensions 3 x 3 cm{sup 2}. Irradiations were performed with a linear accelerator Novalis of 6 MV. Comparison between dose values found with a diode type Sfd detector (IBA dosimetry, Germany) and a diamond detector CVD (PTW-Freiburg) for 2 different sized of field (5 x 5 cm{sup 2} and 10 x 10 cm{sup 2}) on the surface of a water phantom scanning was realized. The total spreading factor (Tsf) measured on surface was of 0.831 ± 4.6%; which is greater 12.9% than Tsf measured at a depth of maximum dose. This difference may be due to the contribution of scattered electrons to the beam exit. The measures must be corroborated with Monte Carlo simulations, which they will be validated on surface by the Abdel-Rahman [et al.] method; this mechanism will determine if the films are useful detectors for in-vivo dosimetry clinically. (Author)

  1. Evaluation of radiosensitivity and correlation between physical and biological dosimetry in a case of vascular radiology; Valoracion de la radiosensibilidad y correlacion entre dosimetria biologica y fisica en un caso de radiologia vascular

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Sebastia, N.; Aparici, F.; Candela, C.; Soriano del Castillo, J. M.; Perez, J.; Gras, P.; Cervera, J.; Alonso, O.; Villaescusa, J. I.

    2013-07-01

    The threshold dose required to produce a deterministic effect or even differences in the degree of the effect produced vary between individuals due to idiopathic causes, at the age or underlying disease. According to this work based on the Society of Interventional Radiology and the Guidelines for patient radiation dose management greater than 60 minutes fluoroscopy time management it is an indirect indicator of a significant radiation dose. According to this guide, instructions post procedure in these cases included a follow-up of the patient. (Author)

  2. Computational voxel phantom, associated to anthropometric and anthropomorphic real phantom for dosimetry in human male pelvis radiotherapy; Fantoma computacional de voxel, associado a fantoma real antropomorfico antropometrico, para dosimetria em radioterapia de pelve masculina

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cleuza Helena Teixeira; Campos, Tarcisio Passos Ribeiro de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares]. E-mail: campos@nuclear.ufmg.br

    2005-07-01

    This paper addresses a computational model of voxels through MCNP5 Code and the experimental development of an anthropometric and anthropomorphic phantom for dosimetry in human male pelvis brachytherapy focusing prostatic tumors. For elaboration of the computational model of the human male pelvis, anatomical section images from the Visible Man Project were applied. Such selected and digital images were associated to a numeric representation, one for each section. Such computational representation of the anatomical sections was transformed into a bi-dimensional mesh of equivalent tissue. The group of bidimensional meshes was concatenated forming the three-dimensional model of voxels to be used by the MCNP5 code. In association to the anatomical information, data from the density and chemical composition of the basic elements, representatives of the organs and involved tissues, were setup in a material database for the MCNP-5. The model will be applied for dosimetric evaluations in situations of irradiation of the human masculine pelvis. Such 3D model of voxel is associated to the code of transport of particles MCNP5, allowing future simulations. It was also developed the construction of human masculine pelvis phantom, based on anthropometric and anthropomorphic dates and in the use of representative equivalent tissues of the skin, fatty, muscular and glandular tissue, as well as the bony structure.This part of work was developed in stages, being built the bony cast first, later the muscular structures and internal organs. They were then jointly mounted and inserted in the skin cast. The representative component of the fatty tissue was incorporate and accomplished the final retouchings in the skin. The final result represents the development of two important essential tools for elaboration of computational and experimental dosimetry. Thus, it is possible its use in calibrations of pre-existent protocols in radiotherapy, as well as for tests of new protocols, besides comparative studies among different clinical protocols. (author)

  3. Dosimetry of Rn-222 in the air in environments located above and below ground level; Dosimetria de Rn-222 no ar em ambientes localizados acima e abaixo do nivel do solo

    Energy Technology Data Exchange (ETDEWEB)

    Cazula, Camila Dias

    2015-07-01

    Exposure of the general population to ionizing radiation comes mainly from natural sources. The main contribution is due to inhalation of radon (Rn-222), a gas that occurs naturally (UNSCEAR, 2000). The Rn-222 concentration in the environment is controlled by factors such as soil permeability and water content, the weather variability, materials used in the foundation and the usual positive pressure differential between the soil and the internal environment. Studies indicate that the concentration of radon shows a wide variation in the basement, ground floor and upper floors of buildings. The objective of this study is to determine radon levels in basements, ground floor and floors above ground level, at a university in the city of Sao Paulo and in one residential building in the city of Peruibe. Rn-222 measurements were performed using the method with nuclear track of solid state detectors (CR-39). The studied environments present Rn-222 concentration well below the values recommended by the International Commission on Radiological Protection, published in the 2009 document, of 300 Bq/m{sup 3} for homes and 1000 Bq/m{sup 3} for the workplace. In the residential building, the concentration of Ra-266, Th-232 and K-40 in the materials used in the building construction was also analyzed, by gamma spectrometry. The effective total dose for the resident due to external exposure was 0.8 mSv y{sup -1}, lower than the annual dose limit for the general public of 1 mSv y{sup -1}. (author)

  4. On line CALDose{sub X}: real time Monte Carlo calculation via Internet for dosimetry in radiodiagnostic; CALDose{sub X} online: Calculos de Monte Carlo em tempo real via Internet para dosimetria em radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, Richard; Cassola, Vagner Ferreira; Lira, Carlos Alberto Brayner de Oliveira; Khoury, Helen Jamil, E-mail: rkramer@uol.com.b, E-mail: vagner.cassola@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Cavalcanti, Arthur; Lins, Rafael Dueire, E-mail: rdl@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Tecnologia e Geociencias. Dept. de Eletronica e Sistemas

    2011-10-26

    The CALDose{sub X} 4.1 is a software which uses thr MASH and FASH phantoms. Patient dosimetry with reference phantoms is limited because the results can be applied only for patients which possess the same body mass and right height that the reference phantom. In this paper, the dosimetry of patients for diagnostic with X ray was extended by using a series of 18 phantoms with defined gender, different body masses and heights, in order to cover the real anatomy of the patients. It is possible to calculate absorbed doses in organs and tissues by real time Monte Carlo dosimetry through the Internet through a dosimetric service called CALDose{sub X} on line

  5. Dosimetry service participation of CIEMAT in intercomparisons 2008-2010 for personal dosimeters EURADOS; Participacion del servicio de dosimetria del CIEMAT en las intercomparaciones EURADOS 2008-2010 para dosimetros personales

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Jimenez, R.; Romero Gutierrez, A. M.; Lopez Moyano, J. L.

    2011-07-01

    Individual monitoring of workers exposed to ionizing radiation requires the use of personal dosimeters. EURADOS (European Radiation Dosimetry Group) recently organized three intercomparison exercises External Personal Dosimetry Services (EPDS): two for body dosimeters in 2008 and 2010 and one for extremity dosimeters in the year 2009.El paper shows and analyzes the results obtained by CIEMAT SDPE participation in all exercises.

  6. Design of a computation tool for neutron spectrometry and dosimetry through evolutionary neural networks; Diseno de una herramienta de computo para la espectrometria y dosimetria de neutrones por medio de redes neuronales evolutivas

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz R, J. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Ingenieria Electrica, Av. Ramon Lopez Velarde No. 801, Col. Centro, Zacatecas (Mexico); Martinez B, M. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Av. Ramon Lopez Velarde No. 801, Col. Centro, Zacatecas (Mexico); Gallego, E. [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, Jose Gutierrez Abascal No. 2, E-28006 Madrid (Spain)], e-mail: morvymmyahoo@com.mx

    2009-10-15

    The neutron dosimetry is one of the most complicated tasks of radiation protection, due to it is a complex technique and highly dependent of neutron energy. One of the first devices used to perform neutron spectrometry is the system known as spectrometric system of Bonner spheres, that continuous being one of spectrometers most commonly used. This system has disadvantages such as: the components weight, the low resolution of spectrum, long and drawn out procedure for the spectra reconstruction, which require an expert user in system management, the need of use a reconstruction code as BUNKIE, SAND, etc., which are based on an iterative reconstruction algorithm and whose greatest inconvenience is that for the spectrum reconstruction, are needed to provide to system and initial spectrum as close as possible to the desired spectrum get. Consequently, researchers have mentioned the need to developed alternative measurement techniques to improve existing monitoring systems for workers. Among these alternative techniques have been reported several reconstruction procedures based on artificial intelligence techniques such as genetic algorithms, artificial neural networks and hybrid systems of evolutionary artificial neural networks using genetic algorithms. However, the use of these techniques in the nuclear science area is not free of problems, so it has been suggested that more research is conducted in such a way as to solve these disadvantages. Because they are emerging technologies, there are no tools for the results analysis, so in this paper we present first the design of a computation tool that allow to analyze the neutron spectra and equivalent doses, obtained through the hybrid technology of neural networks and genetic algorithms. This tool provides an user graphical environment, friendly, intuitive and easy of operate. The speed of program operation is high, executing the analysis in a few seconds, so it may storage and or print the obtained information for further analysis and treatment. (Author)

  7. Results of the ninth exercise of intercomparison in services of personal dosimetry in Argentina Republic in the year of 2011; Resultados del noveno ejercicio de intercomparacion de servicios de dosimetria personal realizado en la Republica Argentina en el ano 2011

    Energy Technology Data Exchange (ETDEWEB)

    Ferrufino, G.A.; Discacciatti, P.A.; Lopez, F.O., E-mail: gferrufino@am.gob.ar [Autoridad Regulatoria Nuclear (ARN), Buenos Aies (Argentina)

    2013-10-01

    In this paper we present the results of the ninth intercomparison exercise personal dosimetry services, conducted by the Nuclear Regulatory Authority in 2011. The exercise was designed to evaluate the performance of laboratories providing personal dosimetry services in Argentina , for X-rays and gamma radiation fields . This exercise was organized by the Nuclear Regulatory Authority with the Ministry of Health of the Nation and the Regional Reference Laboratory Centre for Dosimetry of the National Atomic Energy Commission . The irradiations were carried out in full accordance with ISO 4037-3 . Participates all private companies in Argentina serving all personal dosimetry laboratories and agencies, provincial and national. Furthermore, the Laboratories from Cuba, Brazil and Uruguay also participate. The performance of a laboratory is considered acceptable if it meets the criteria established in the IRAM- ISO 14146 , which states: 'It is recognized that at most, one-tenth of dosimeters irradiated to exceed the limits'. Of all of the laboratories that participated , 68% reported their results within the acceptance criteria above. The primary objective of this intercomparison exercise is to provide an objective tool to evaluate the ability of personnel dosimetry services. (author)

  8. Protocol for adaptation of internal dosimetry techniques for planning of individualized doses of {sup 131}I in pediatric patients; Protocolo para adaptacao de tecnicas de dosimetria interna para planejamento de doses individualizadas de {sup 131}I em pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Biancardi, Rodrigo

    2011-07-01

    The optimization of radiation doses is emphasized in diseases with good prognosis, as differentiated thyroid carcinomas, especially in pediatric patients, since the radiation risk is conversely proportional to age. Aiming to establish individual treatment planning, it has been studied four dosimetry methodologies (external dose monitoring, image quantification, urine and blood bioassay) for four 13.3 {+-} 1.5-year-old female patients, who received 107 {+-} 15 MBq (2,9 {+-} 0,4 mCi) for tracer dose and 5.5 {+-} 0.3 GBq (149 {+-} 8 mCi) for thyroid ablation. Effective half-lives, residence times and cumulated activities were estimated in organs and tissues with iodine uptake, through planar images quantification by conjugate-view and attenuation correction, in order to compare biokinetic behavior in tracer dose and ablative dose phases. For external monitoring, two patients had similar whole-body effective half-lives in both phases. For this methodology, despite the uncertainties associated to measurements, equipment used and procedures performed were adequate. For urine bioassay, there were not similarities among the patients whole-body effective half-lives. Through blood bioassay, it was observed that 0.2 % of the administered activity for ablative dose remained in the blood until 76 hours after administration. The external monitoring allowed estimating effective doses in patients mothers by conversion of the environmental equivalent dose. In the ablative dose phase, the effective doses resulted in 1.3 {+-} 0.3 mSv in the hospital and 0.3 {+-} 0.1 mSv in patients houses. (author)

  9. Male patients dosimetry undergoing brain PET/CT exam for diagnosis of mild cognitive impairment; Dosimetria de pacientes masculinos submetidos ao exame de PET/CT cerebral para diagnostico de comprometimento cognitivo leve

    Energy Technology Data Exchange (ETDEWEB)

    Santana, P.C.; Mamede, M.; Carvalho, F.M.V., E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Fac. de Medicina. Departamento de Anatomia e Imagem; Mourao, A.P. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Eletrica; Silva, T.A.; Oliveira, P.M.C. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-08-15

    Diagnosis of Mild Cognitive Impairment (MCI) can indicate an initial dementia framework, or increase in the likelihood of developing this. The PET/CT (positron emission tomography associated with computed tomography) has shown excellent prospects for MCI diagnosis. The PET/CT helps diagnosis, but the patients effective dose is higher, it depends on the computed tomography (CT) protocol and the radiopharmaceutical patient injected activity. This study evaluates the dose in 38 male patients undergoing this technique for MCI diagnosis. To assess the radiation level from CT modality imaging was used TLD100 detectors embedded in a male anthropomorphic Alderson Randon® phantom, undergoing the same imaging protocol to which patients were referred. The dose resulting of radiopharmaceutical injected activity was estimated using the ICRP106 model proposed. The PET / CT effective dose for producing image was (5.12 ± 0.90) mSv. The contribution to the effective dose due to the FDG brain incorporation was (0.12 ± 0.01) mSv and thyroid (0.13 ± 0.02) mSv. The effective dose contribution due to brain and thyroid CT irradiation was (0.18 ± 0.01) mSv and (0.010 ± 0.001) mSv, respectively. The use of optimized CT protocols and FDG injected activity reduction can assist in this procedure dose reduction. (author)

  10. General criteria for validation of dosimetry methods in the context of a quality system ISO / IEC 17025; Criterios generales sobre validacion de metodos de dosimetria en el marco de un sistema de calidad ISO/IEC 17025

    Energy Technology Data Exchange (ETDEWEB)

    Martin Garcia, R.; Navarro Bravo, T.

    2011-07-01

    The accreditation of a testing laboratory in accordance with ISO / IEC 17025 recognizes the technical competence of a laboratory to perform certain tests. One of the requirements of that rule states that laboratories must demonstrate that the methods used are valid and appropriate for the intended use and customer needs. This demonstration is accomplished through the process of validation of methods, defined in the rule it self as {sup c}onfirmation by examination and provision of objective evidence that the requirements for a particular purpose{sup .} The process of validating a test method should be well planned and documented, including the requirements under the applicable rules and criteria established by the laboratory to comply with these requirements.

  11. Fabrication and electrical characterization of polyaniline-silicon heterojunction for gamma radiation dosimetry application; Fabricacao e caracterizacao eletrica de heterojuncoes de polianilina - silicio para aplicacao em dosimetria de radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Laranjeira, Jane Maria Goncalves

    2004-08-15

    In this work a technique has been developed to fabricate high quality polyaniline-silicon heterojunction diodes for use as gas and/or ionizing radiation sensors. Polyaniline thin films (40 nm thick) produced by spin-coating on silicon substrates, were the active part of the junction structure. The devices presented excellent reproducibility of their electrical characteristics with high rectification ratio, 60,000 at {+-}1.0 V, and typical reverse current at - 1.0 V of 3 nA at 295 K. A G/I x G plot has been used to analyze the current-voltage characteristics, yielding typical series resistance of 4 k{omega} {+-} 5% and ideality factor in a range of 1,9 {+-} 0.5%. The heterojunction diode presents high sensitivity to gamma radiation in the dose range of 3 x 10{sup -2} to 7 kGy with a linear response in the forward and reverse bias. The excellent electrical characteristics together with the linear response with the dose, strongly suggest the application of this device for spectrometry or dosimetry of high doses of gamma radiation. These devices presented high sensitivity to gas moistures such as ammonia, nitric acid and trichloroethylene. In both cases the sensitivity was observed through shifts of the current-voltage curves, which can be easily monitored to provide a calibration curve of the sensor either as a radiation dosimeter or as a gas sensor for use in applications for gas monitoring or radiation dosimetry. Several aspects of the reliability physics of silicon-polyaniline heterojunction, such as degradation effects induced by local heating, charge trapping and temperature changes, have been discussed. These results further confirm the quality of the devices electrical characteristics and their suitability for radiation and gas sensors applications. Another interesting results presented in this work was the use of polyemeraldine nanofilms (thickness in the range 30-50 nm) deposited by 'spin coating' on glass substrates as an optical dosimeter for gamma radiation based on the color change of the polymer. The nanofilms devices were characterized by UV visible absorption spectroscopy. The deep blue color, characteristic of undoped polyaniline films before irradiation, becomes subsequently green as the film is being irradiated, and the film absorption coefficient exhibits a linear dependence with the logarithm of the irradiation dose from I to 10 kGy. (author)

  12. Evaluation of detectors for blood bioanalysis in Lu-177 and I-131 therapies for bone marrow dosimetry; Avaliacao de detectores para bioanalise de sangue em terapias com Lu-177 and I-131 para dosimetria de medula ossea

    Energy Technology Data Exchange (ETDEWEB)

    Degenhardt, Amilie Louize

    2016-10-01

    The measures traceability is mandatory for minimizing uncertainties in internal dosimetry for radiopharmaceuticals clinical studies and ensures the quality of the standard. Equipment should have resolution and efficiency compatible with radionuclides energies and, additionally, be able to quantify variations in human bodies' activities samples since the initial administration near the minimum residual activities. For testing three equipment (ionization chamber Capintec 25R, sodium iodine scintillator LTI Genesys Gamma-1 and high hyperpure germanium detector Canberra), they were prepared Lu-177 and I-131 radiation sources simulating patient's blood samples activities by adopting the following hypothesis: (1) initial activities according the Brazilian protocols; (2) blood volume in the whole body (5.3 L for adult men and 1.4 L for 5 years-old children); (3) effective half-lives (1.61 h and 42.9 h for Lu-177 bi-exponential adjustment and 15.7 h for I-131 mono-exponential adjustment); (4) sampling between 30 min and 168 h; (v) blood density adjustments. The standard sources were measured in the secondary standard ionization chamber Centronics IG11 at the Laboratorio Nacional de Metrologia das Radiacoes Ionizantes. The Capintec ionization chamber efficiencies ranged, respectively for I-131 and Lu-177, between (111.58±0.02)% and (102.27±0.01)% and HPGe semiconductor detector efficiencies ranged, respectively, between (89.40±0.03)% and (87.80±0.04)%. For the NaI detector, when the Lu-177 sources were positioned inside the detector the efficiencies ranged between (12.66±0.01)% and (11.54± 0.07)% and when the sources were positioned at 5 cm and 10 cm from the detector the efficiencies decreased to less than 5%. For I-131 sources positioned inside the detector, the efficiencies ranged between (29.76±0.21)% and (30.20±0.04)% and they decreased to less than 5% when they were positioned at 5 cm and 10 cm from the detector (deviation greater than 95%). Comparing the reference values from the secondary standard ionization chamber for the I-131 standard sources, Capintec ionization chamber showed 111.58% (11,58% deviation), NaI detector 29.83% and HPGe detector 87.80% from the absolute values. For Lu-177 standard sources, the ionization chamber showed 102% (2% deviation), NaI detector 12.67% and HPGe detector 89.40% from the reference values. The variations observed for the equipment's efficiencies may be attributable to the radionuclides energies, since the experimental conditions were maintained (distance source-detector, detector type, temperature, background radiation). Presuming that the time of sampling and activities simulation were adequate, the equipment better performances were: the ionization chamber for the first day collecting samples and the HPGe detector for the second and subsequent days sampling. (author)

  13. Thermoluminescent dosimetry of beta radiations of {sup 90} Sr/ {sup 90} Y using amorphous ZrO{sub 2}; Dosimetria termoluminiscente de radiaciones beta de {sup 90} Sr/ {sup 90} Y usando ZrO{sub 2} amorfo

    Energy Technology Data Exchange (ETDEWEB)

    Rivera M, T. [CICATA-Legaria, IPN, Legaria Num. 694, 11500 Mexico D.F. (Mexico); Olvera T, L.; Azorin N, J.; Barrera R, M.; Soto E, A.M. [UAM-I, 09340 Mexico D.F. (Mexico)

    2005-07-01

    In this work the results of studying the thermoluminescent properties (Tl) of the zirconium oxide in its amorphous state (ZrO{sub 2}-a) before beta radiations of {sup 90} Sr/ {sup 90} Y are presented. The amorphous powders of the zirconium oxide were synthesized by means of the sol-gel technique. The sol-gel process using alkoxides like precursors, is an efficient method to prepare a matrix of zirconium oxide by hydrolysis - condensation of the precursor to form chains of Zr-H{sub 3} and Zr-O{sub 2}. One of the advantages of this technique is the obtention of gels at low temperatures with very high purity and homogeneity. The powders were characterized by means of thermal analysis and by X-ray diffraction. The powders of ZrO{sub 2}-a, previously irradiated with beta particles of {sup 90} Sr/{sup 90} Y, presented a thermoluminescent curve with two peaks at 150 and 257 C. The dissipation of the information of the one ZrO{sub 2}-a was of 40% the first 2 hours remaining constant the information for the following 30 days. The reproducibility of the information was of {+-} 2.5% in standard deviation. The studied characteristics allow to propose to the amorphous zirconium oxide as thermoluminescent dosemeter for the detection of beta radiation. (Author)

  14. Thermoluminescent dosimetry of ionizing radiations using ZrO{sub 2} prepared at low temperatures; Dosimetria termoluminiscente de radiaciones ionizantes usando ZrO{sub 2} preparado a bajas temperaturas

    Energy Technology Data Exchange (ETDEWEB)

    Rivera M, T.; Diaz G, J.A.I. [CICATA-IPN, Legaria 694, 11500 Mexico D.F. (Mexico); Olvera T, L.; Azorin N, J.; Barrera S, M.; Soto E, A.M. [UAM-I, 09340 Mexico D.F. (Mexico)

    2005-07-01

    The thermoluminescent dosimetry (TLD) it is a versatile tool for an evaluation of dose of ionizing radiation. A great variety of ceramic materials and their different physical forms allow a determination of the ionizing radiation in a wide dose interval. In this work the results of studying those thermoluminescent characteristics (TL) of the zirconium oxide obtained by means of the sol-gel technique to low temperatures are presented. To these temperatures the material was obtained in its amorphous state (ZrO{sub 2}-a). The structural characteristics of ZrO{sub 2}-a they were obtained by means of X-ray diffraction. The TL characteristics studied were: TL curve, reproducibility of the TL signal and the fading of the information. The powders of ZrO{sub 2}-a, previously irradiated with beta particles of {sup 90}Sr/ {sup 90}Y, they presented a thermoluminescent curve with two peaks at 150 and 260 C. The fading of the information of the one ZrO{sub 2}-a it was of 20% during the first two hours starting from this time there was one lost of information of 5% to the finish of the 30 days. The reproducibility of the information was of {+-} 2.5% in standard deviation. (Author)

  15. Dosimetry with semiconductor diodes in the application to the full-length irradiation technique of electrons; Dosimetria con diodos semiconductores en la aplicacion a la tecnica de irradiacion de cuerpo entero de electrones

    Energy Technology Data Exchange (ETDEWEB)

    Madrid G, O. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Calz. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

    2012-10-15

    The use of charged particles as electrons for the tumor-like lesions treatment to total surface of skin is not very frequent, the types of fungo id mycosis and cutaneous lymphomas compared with other neoplasms they are relatively scarce, however for the existent cases a non conventional technique should be contemplated as treatment alternative that can reach an effective control. In this work the variables of more influence with ionization chamber and semiconductor diodes are studied for to determine the quality of an electrons beam. (Author)

  16. Effect of the peptide Tat(49-57) on the bio-distribution and similar radiopharmaceuticals dosimetry of the bombesin; Efecto del peptido TAT(49-57) sobre la biodistribucion y dosimetria de radiofarmacos analogos de la bombesina

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C. L.

    2011-07-01

    The gastrin-releasing peptide receptor (GRP-r) is over-expressed in prostate and breast cancer. {sup 99m}Tc-Bombesin ({sup 99m}Tc-Bn) has been reported as a radiopharmaceutical with specific cell GRP-r binding. The HIV Tat(49-57)-derived peptide has been used to deliver a large variety of molecules to cell nuclei. New hybrid radiopharmaceuticals of type {sup 99m}Tc-N{sub 2}S{sub 2}-Tat(49-57)-Lys{sup 3}-Bn ({sup 99m}Tc-Tat-Bn) and {sup 188}Re-N{sub 2}S{sub 2}-Tat(49-57)-Lys{sup 3}-Bn ({sup 188}Re-Tat-Bn), would increase cell uptake and internalized in cancer cell nuclei could act as an effective system of targeted radiotherapy using Auger and internal conversion (I C) electron emissions near DNA. The aim of this research was to prepare and assess in vitro and in vivo uptake kinetics in cancer cells of {sup 99m}Tc/{sup 188}Re-Tat-Bn and the in vitro nucleus and cytoplasm internalization kinetics in GRP receptor-positive cancer cells as well as to evaluate the subcellular-level radiation absorbed dose associated with the observed effect on cancer cell DNA proliferation. Structures of N{sub 2}S{sub 2}-Tat-Bn and Tc/Re(O)N{sub 2}S{sub 2}-Tat-Bn were calculated by an Mm procedure. {sup 99m}Tc-Tat-Bn and {sup 188}Re-Tat-Bn were synthesized and stability studies carried out by HPLC and I TLC-Sg analyses in serum and cysteine solutions. In vitro internalization was tested using human prostate cancer Pc 3 cells and breast carcinoma cell lines MDA-Mb 231 and MCF 7. Nuclei from cells were isolated using a nuclear extraction kit. Total disintegrations in each subcellular compartment were calculated by integration of experimental time activity kinetic curves. Nucleus internalization was corroborated by con focal microscopy images using immunofluorescent labelled Tat-Bn. Biodistribution was determined in Pc 3 tumor-bearing nude mice. The Penelope code was used to simulate and calculate the absorbed dose by contribution of {beta}, Auger and I C electrons in the cytoplasm and nucleus using geometric models built from immunofluorescent cell images. A cell proliferation kit was used to evaluate DNA concentration after cancer cell incubation with {sup 99m}Tc-Tat-Bn. Results showed a minimum energy of 271 kcal/mol for N{sub 2}S{sub 2}-Tat-Bn and 300 kcal/mol for Re/Tc(O)N{sub 2}S{sub 2}-Tat-Bn. {sup 99m}Tc/{sup 188}Re-Tat-Bn radiochemical purity was >90%. In vitro studies demonstrated stability in serum and cysteine solutions, specific cell receptor binding and internalization in three cell lines was significantly high. The tumor-to muscle radioactivity ratio was 8.5 for {sup 99m}Tc-Tat-Bn. Also it showed that 59.7%, 61.2% and 41.5% of total disintegrations per unit of {sup 99m}Tc-Tat-Bn activity (1 Bq) bound to the cell occurred in the nucleus of Pc 3, MCF 7 and MDA-Mb 231, respectively and 63.36%, 65.70% and 45.55% of total disintegrations per 1 Bq of {sup 188}Re-Tat-Bn bound to the cell occurred in the nucleus of these three cell lines respectively. The {sup 99m}Tc-Tat-Bn absorbed doses delivered to nuclei were 0.142 mGy/Bq{center_dot}s (Pc 3), 0.434 Gy/Bq{center_dot}s (MCF 7) and 0.276 mGy/Bq{center_dot}s (MDA-Mb 231) and from {sup 188}Re-Tat-Bn were 0.156 mGy/Bq{center_dot}s (Pc 3); 0.368 mGy/Bq{center_dot}s (MCF 7) and 0.251 mGy/Bq{center_dot}s (MDA-Mb 231). {sup 99m}Tc-Tat-Bn produced a significant decrease in cellular proliferation of Pc 3 (52.98%), MCF 7 (45.71%) and MDA-Mb 231 (35.80%) with respect to untreated cells. These hybrid radiopharmaceuticals are potentially useful in imaging and therapy of breast and prostate cancer. (Author)

  17. Establishment of a radiotherapy service with a linear accelerator (photons): acceptance tests, dosimetry and quality control; Implantacao de um servico de radioterapia com acelerador linear (fotons): testes de aceitacao, dosimetria e controle de qualidade

    Energy Technology Data Exchange (ETDEWEB)

    Berdaky, Mafalda Feliciano

    2000-07-01

    This work presents the operational part of the final process of the establishment of a radiotherapy service with a linear accelerator (6 MeV photon beams), including the acceptance tests, commissioning tests and the implementation of a quality control program through routine mechanical and radiation tests. All acceptance tests were satisfactory, showing results below the allowed limits of the manufacturer, the commissioning tests presented results within those of the international recommendations. The quality control program was performed during 34 months and showed an excellent stability of this accelerator. (author)

  18. Verification of an algorithm of cono collapsed through the IAEA TECDOC 1583 protocol and dosimetry with radiochromic films; Verificacion de un algoritmo de cono colapso mediante en protocolo IAEA TECDOC 1583 y dosimetria con peliculas radiocromicas

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Viera Cueto, J. A.; Benitez Villegas, E. M.; Bodineau Gil, C.; Parra Osorio, V.; Garcia Pareja, S.; Casado Villalon, F. J.

    2013-07-01

    The objective of this study is to verify the characterization of the collapsed cone algorithm of an SP using this Protocol. In addition, given that it only offers details of dose values measured at discrete points, measures are complemented by a gamma test distributions 2D of doses in different cases using film radiochromic. (Author)

  19. Relative dosimetry of photon beam of 6 MV with a liquid ionization chamber; Dosimetria relativa de un haz de fotones de 6 MV con una camara de ionizacion liquida

    Energy Technology Data Exchange (ETDEWEB)

    Benitez Villegas, E. M.; Casado Villalon, F. J.; Martin-Cueto, J. A.; Caudepon Moreno, F.; Garcia Pareja, S.; Galan Montenegro, P.

    2011-07-01

    The increasing use of reduced size fields in the special techniques of treatment generates regions with high dose gradients. It therefore requires the use of detectors that present high spatial resolution. The aim of this study is to compare the dosimetric measurements obtained with a liquid ionization chamber PTW MicroLion recently acquired with other commonly used detectors for a photon beam of 6 MV linear electron accelerator Varian 600DBX.

  20. Dosimetry in occupational exposure workers of the medical institutes of the University San Francisco Xavier de Chuquisaca; Dosimetria en TOEs de los institutos medicos de la Universidad San Francisco Xavier de Chuquisaca

    Energy Technology Data Exchange (ETDEWEB)

    Zambrana Z, A. J.; Castro S, O.; Huanca S, E.; Torrez C, M. [Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, Instituto de Medicina Nuclear de Sucre, Plaza Libertad No. 1, Sucre (Bolivia, Plurinational State of); Villca Q, I., E-mail: nuclear_sre@entelnet.bo [Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, Instituto Nacional de Cancerologia Dr. Jose Cupertino Arteaga, Plaza Libertad No. 1, Sucre (Bolivia, Plurinational State of)

    2014-08-15

    In this work is made a retrospective analysis of the record, of the dosimetric control readings processed by the Dosimetry Laboratory of the Instituto Boliviano de Ciencia y Tecnologia Nuclear, as regulator entity at national level for Occupational Exposed Workers (OEWs) to ionizing radiations, of the Medical Institutes of the Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, by a period of 10 and 15 years. The results showed that in the Nuclear Medicine Institute of Sucre, the Accumulated Occupational Exposure of a total of 393 readings of 15 OEWs was of 20.4 mSv, identifying as maximum value 10.2 mSv, in the official that develops the Radio-pharmacy activities (elution, fractionation, preparation and management). In the Instituto Nacional de Cancerologia Dr. Jose Cupertino Arteaga the dosimetric background registered an Accumulated Occupational Exposure of a total of 1319 readings of 50 OEWs of 309.69 mSv, with a maximum value of 62.30 mSv, corresponding to the worker of the technical area (maintenance, adjustment and calibration). Comparison that allows to infer that the difference is due mainly to the radio-active source type {sup 99m}Tc Vs {sup 60}Co utilized in these health centers. (Author)

  1. Personnel dosimetry of extremities by using Harshaw rings XD-100 at Centro Regional de Ciencias Nucleares, CRCN, Brazilian CNEN; Dosimetria pessoal de extremidades utilizando aneis Harshaw XD-100 no Centro Regional de Ciencias Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Ricardo de Andrade; Vilela, Eudice; Nogueira, Maria do Socorro; Ferreira Filho, Alfredo Lopes; Castro, Walber Amorim [Centro Regional de Ciencias Nucleares (CRCN), Recife, PE (Brazil)]. E-mail: ral@elogica.com.br

    2000-07-01

    Data concerning calibration and type tests of an extremity system based on XD100 rings (Harshaw) are presented. Dosemeter used is a thermoluminescent chip inserted in a sealed pouch and was read out using a Harshaw 6600 reader. The dosimetric system complied with all ISO/DIS 12794-1 draft report suggested tests, in which this work was based on. This work obtained results point to the applicability of those recommendations to Brazilian institutes and suggest its adoption by the national regulatory commission. (author)

  2. Contribution to the planning and dosimetry of photon beams applied to radiosurgery and stereotactic radiotherapy; Contribuicao ao planejamento e a dosimetria de feixes de fotons aplicados a radiocirurgia e a radioterapia estereotaxica

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Walter Menezes

    2003-08-15

    Radiosurgery and stereotactic radiotherapy are irradiation techniques that use small diameter photon beams for treating intracranial lesions such as pituitary adenomas, acoustic tumors and arterio-venous malformations which are inaccessible for surgery. These treatment techniques are characterized by the use of very small radiation beams which deliver a precisely measured dose to the target volume, while sparing the surrounding healthy tissue. Treatment can be performed by using multiple {sup 60}Co gamma-ray sources (in the so-called 'Gamma Knife'), charged particles or X-ray beams produced by linear accelerators. The prescribed dose can be given in a single session or in multiple fractions, as in conventional radiotherapy. The success of the treatment depends, among other factors, of the accurate determination of the parameters that characterize the radiation beam produced by the equipment, as well as, of a well designed quality assurance program. In this study, the dosimetric parameters of a set of collimating cones of a Radionics{sup TM} treatment system applied to two 6 MV- photon beams (Clinac 600C - Varian{sup TM}, and Mevatron MD2 - Siemens{sup TM}) were evaluated by using a water filled PMMA simulator. Measurements were carried out for photon beam diameters ranging from 12.5 to 40.0 mm for the Clinac-600C and from 5.0 to 50.0 mm for the Mevatron MD2. The parameters were evaluated by using a parallel plate ionization chamber (Markus), Kodak X-Omat V dosimetric films, thermoluminescent dosemeters (Harschaw, TLD-100) and photodiodes. The maximum tissue-ratio, the off-axis profile and the output factors were determined and the results were compared to those reported elsewhere. A study of the dosimetric characteristics of some commercially available phototransistors was also carried out. The results showed that these electronic components can be successfully used for measuring the dosimetric parameters of small diameter photon beans used in radiosurgery. Measurements were also performed with thermoluminescent dosimeters in order to verify the degree of compliance between the doses calculated through the Radionics{sup TM} Planning System and the actual treatment dose. This was accomplished by using a Rando(R) anthropomorphic phantom. The results showed that the two doses agree within {+-} 2%. The influence of the presence of inhomogeneities within the irradiated volume, due to the presence of air or bone in the radiation path was assessed. The results showed that these inhomogeneities significantly affect both the dose distribution pattern and the beam profiles in the treatment volume. The results of this study show that the dosimetry of small diameter radiation beams is still challenging, due mainly to the limited resolution of available detectors and to the lack of lateral equilibrium in small diameter radiation beams. (author)

  3. Occupational dosimetry commissioning of a PET-CT: learning curve and staff participation; Dosimetria ocupacional en la puesta en funcionamiento de un PET-TC curva de aprendizaje y participacion del personal

    Energy Technology Data Exchange (ETDEWEB)

    Sierra Diaz, F.; Hurtado Sanchez, A.; Gomez Cortes, M. S.; Gonzalez Ruiz, C.; Gago Gomez, P.; Ruiz Galan, G.; Lopez Bote, M. A.

    2011-07-01

    The Nuclear Medicine Department, Hospital General Universitario Gregorio Maranon has been in clinical use PET-CT equipment at the end of 2009. The Dosimetry and Radiation Protection Service has been conducting surveillance at the facility and individual environmental dosimetry. Following the obligations contained in the performance specifications of the authorization granted by the Nuclear Safety Council (CSN), during the first year of the PET-CT has been tracking personal dosimetry of the professionals involved. As a novelty, had to take the ring dosimetry to control the dose equivalent in the hands instead of the normal wrist.

  4. Analysis of the uncertainty of semiconductor diodes in dosimetry in vivo of brachytherapy treatments; Analisis de la incertidumbre de diodos semiconductores en dosimetria in vivo de tratamientos de braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, K.; Rodriguez, P.; Prieto, D.; Esteve, S.; Colmenares, R.; Bejar, M. J.; Ordonez, J.; Capuz, B.; Moris, R.

    2013-07-01

    Brachytherapy involves the administration of high doses in some parts of healthy tissue, especially in the organ at risk coming to the region of prescription, as it is the case of the rectum and bladder in various gynecological treatments. The possibility of trying to know the actual dose in vivo through the use of dosimeters of semiconductor diode could be. However, to know if you can have certainty in these measures it is necessary to establish the uncertainty previously. The objective of this work consists in estimating the intrinsic uncertainty of diodes and compare it with other dosimetry uncertainties such as the one given the displacement of these between the planning and administration of treatment. (Author)

  5. Study and characterization of dosimeter LiF:Mg,Cu,P for using in aeronautical dosimetry; Estudo e caracterizacao do dosimetro de LiF:Mg,Cu,P para utilizacao em dosimetria aeronautica

    Energy Technology Data Exchange (ETDEWEB)

    Flavia, Hanna, E-mail: hannasantana.f@gmail.com [Universidade Paulista (UNIP), Sao Jose dos Campos, SP (Brazil); Federico, Claudio; Lelis, Odair; Pereira, Heloisa; Pereira, Marlon, E-mail: claudiofederico@ieav.cta.br [Instituto de Estudos Avancados (EFA-A/IEAV), Sao Jose dos Campos, SP (Brazil). Div. de Fisica Aplicada

    2014-07-01

    The effects of cosmic ionizing radiation incidents in aircraft components and crews has been a source of concern and motivated increasingly studies and improvements in the area. The low dose rates involved in this radiation field in aircraft flight altitudes imply Dosimetric necessity of using materials with high efficiency of detection, to enable studies lower cumulative doses resulting in shorter routes or lower altitude. The choice of thermoluminescent dosimeters LiF: Mg, Cu, P was done by having a detection efficiency of about fifteen times higher than its predecessor (LiF: Mg, Ti), and therefore, applied in very low doses dosimetry, and environmental dosimetry . The implementation of the use of pair dosimetric TLD-600H and 700H-TLD will serve as support for testing and studies on the effects of low doses of cosmic radiation in environmental dosimetry applied in the aviation environment in the usual flight altitudes. In this paper are presented the results of development of a methodology for dosimetry low doses of gamma radiation and neutrons using the pair dosimetric TLD-600H and 700H-TLD. The results demonstrate a sensitivity of dosimeters well above the dosimeters LiF: Mg, Ti confirming its suitability for dosimetry of low doses.

  6. Internal dosimetry of radiopharmaceuticals derived of antitumor polypeptide isolated from venoms: Crotalus durissus terrifucus and Scorpaena plumieri;Dosimetria interna de radiofarmacos derivados de polipeptideos antitumorais isolados dos venenos de: Crotalus durissus terrificus e Scorpaena plumieri

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Henrique Martins de

    2009-07-01

    The identification of new diagnostic and therapeutic agents capable of inhibiting tumor growth is essential for improving the prognosis of patients suffering from malignant tumors (glioma, breast and others). In this context, natural products (plants and animals) are a rich source of substances with potential antitumor. Despite knowledge of the etiology and pathology of tumors little progress has been observed in the area of diagnosis. Molecules of snake venoms have been shown to play an important role not only in the survival and proliferation of tumor cells but also in the process of tumor cell adhesion, migration and angiogenesis. Polypeptides isolated from the venom of the snake, Crotalus durissus terrificus, Crtx, and Scorpaena plumieri fish, SPGP, have antitumor activity against malignant tumors. It was shown that similar radio iodines Crtx and SPGP, {sup 125}I-Crtx and {sup 125}I-SPGP, can interact specifically with malignant tumors and induce cell death. Prototype-based radiopharmaceuticals Crtx and SPGP containing radioiodine 1311 were able to produce diagnostic images to accumulate specifically in the tumor site. The present study aimed at evaluating the potential radiological safety and diagnostic/therapeutic efficacy of {sup 131}I-Crtx {sup l31}I-SPGP and (evaluated from the biokinetic data in mice bearing Ehrlich tumor) were treated by the MIRD formalism to carry out internal dosimetry studies. Absorbed doses due to the uptake of {sup 131}I-Crtx and {sup 131}I-SPGP were determined in various organs of mice and implanted into the tumor. The results obtained for the animal model were extrapolated to humans by assuming a similar concentration ratio among the various tissues between mice and humans. In extrapolation, we used the masses of human organs of the phantom of Cristy/Eckerman. Both radiation penetrating and non penetrating of {sup 131}I on the tissue were considered in dose calculations. The absorbed dose in the bone marrow due to the administration of {sup 131} I-Crtx was 0.01 mGy/370MBq for both intravenous injection and for the intratumoral injection. In tumor, the value was 3.28 mGy/370MBq for intravenous injection and 107.18 mGy/370MBq for intratumoral injection. For the administration of {sup 131}I-SPGP values for the bone marrow were 1.34 mGy/370MBq for intravenous injection and 0.12 mGy/370MBq for intratumoral injection. In tumor, 256.29 mGy/370MBq for intravenous injection and 895.69 mGy/370MBq for intratumoral injection. The results suggest good radiation safety for both radiopharmaceuticals considering the values found for the bone marrow by both intratumoral and intravenous routes, in view of the importance of this body to generate blood cells. The results for the tumor intravenously indicate diagnostic applicability for both molecules. Through intratumoral, the values suggest the feasibility for use of {sup 131}I-Crtx and of {sup 131}I-SPGP as a therapeutic agent, given the persistence of radioactivity in the tumor site. Although {sup 131}I-Crtx has proved to be more secure for applications in diagnosis, its potential for application in internal radiotherapy is lower than that of {sup 131}I-SPGp. Both {sup 131}I-Crtx and {sup 131}I-SPGP, proved to be good prototypes for the development of radiopharmaceuticals. This study indicates that is necessary the synthesis of analogues with lower uptake in healthy organs and a higher tumor uptake, as well as pharmaceutical formulations, using nano technology, such as liposomes, nano-materials for controlled release of drugs. (author)

  7. Dosimetry of the energy of the electrons beam and virtual distance of the source of a lineal accelerator; Dosimetria de la energia del haz de electrones y distancia virtual de la fuente de un acelerador lineal

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, A.; Garcia, B.; Ramirez, J.; Marquina, J., E-mail: andres.gonzales@aliada.com.pe [ALIADA, Oncologia Integral, Av. Jose Galvez Barrenechea 1044, San Isidro, Lima 27 (Peru)

    2014-08-15

    The objectives of this work were to characterize, to gauge the energy of a electrons beam of 12 MeV and to find the virtual distance of the source for a lineal accelerator Trilogy-Varian. For the characterization, calibration and to find the virtual distance of the source of a lineal accelerator Trilogy-Varian, a water phantom was used (cylindrical Cuba 3-D) of Sun-Nuclear. The following values were found: R{sub 50.ion} = 4, 95 g/cm{sup 2}, R{sub 50} = 5, 04 g/cm{sup 2}, Z{sub ref} = 2,92 g/cm{sup 2}, Z{sub max} = 2, 60 g/cm{sup 2}. In the calibration was found D{sub W,Q}(Z{sub max}) = 1, 0015 c Gy/Um. In the profile In-plane was measured a symmetry and flatness of 1, 9% and 1, 6% respectively. In the profile Cross-plane a symmetry was measured and flatness of 1, 9% and 1, 3% respectively. The virtual distance regarding the source was of DFS (virtual) =105,81 cm. The electrons beam of 12 MeV was characterized and gauged satisfactorily, were carried out the In-plane and Cross-plane profiles, obtaining all the parameters inside the acceptance limit. The virtual distance of the source was of 105,81 cm. (Author)

  8. Technical requirements for implementation of an individual monitoring service for evaluation of operational quantity HP(10) using thermoluminescent dosimetry; Requisitos tecnicos para a implantacao de um servico de monitoracao individual externa de corpo inteiro para fotons utilizando dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Francisco, Adelaide Benedita Armando

    2016-11-01

    This work aims to establish technical requirements for the development of a TLDs system for the assessment of operational quantity H{sub P}(10), in order to implement an external individual monitoring service in countries who do not have. This allows a better understanding of the technic and the thermoluminescent dosimetry system, thus contributing to identify the technical criteria to be followed by a dosimetry laboratory and evaluation of the dosimetric system performance. For this, the review of the specific literature of the dosimetry field was conducted and later the type and performance tests that must be followed by a dosimetric system were reproduced in practice. In additional was made a analysis of internationals standards norms and the technical regulation used in Brazil, to define the essentials type testes to a dosimetric system. To check the performance of a dosimetry system, a performance analysis of the Brazilian TLDs system was carried out over the past 6 years using the trumpet curve, where it was observed that most of TLDs system, in this review period, were approved and have excellent performance. The technical requirements for the development of a thermoluminescent dosimetry system ensure that the system provides technically reliable results and allow demonstration of compliance with the standard criteria established by national and international standards, and the implementation of the dosimetry system, is verified the compliance of the annual doses limits set for occupationally exposed. (author)

  9. Study and parameters survey for iodine-125 source dosimetry to be applied in brachytherapy; Estudo e levantamentos de parametros para dosimetria de fontes de iodo-125 aplicadas em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Eduardo Santana de

    2011-07-01

    The use of brachytherapy technique with iodine-125 seeds to prostate cancer treatment has been used for decades with good clinical outcomes. To aim the Brazilian population necessities, IPEN-CNEN/SP developed the iodine-125 seed prototype with national technology. The objectives of this work are the development and the study of dosimetric procedures associates with the experimental acquisition of the useful parameters for the iodine-125 dosimetric characterization and to evaluate if the developed procedures, in this work, have the basic conditions to determinate the dosimetric analysis, that are fundamental for clinical procedures. The dosimeters selected for the analysis are the TLD-100 (LiF:Mg,Ti), initially these dosimeters were submitted for two selection steps to choose the dosimeters more reproducible for the dosimetric analysis. The two steps were the selection by the mass of the dosimeters and the reproducibility after four irradiation series in a Cobalt-60 irradiator (CTR-IPEN). Afterwards these steps, the dosimeters were irradiated in linear accelerator with 6 MV energy (Service of Radiotherapy - Hospital Israelita Albert Einstein) to yield the individual calibration factors to each dosimeter. After, the dosimeters were used to the irradiations with iodine-125 seed, 6711 model, (GE-Healthcare). The irradiations and others analysis with iodine-125 seeds yield the useful values for the determination of the parameters suggested by the AAPM (American Association of Physicists in Medicine): constant of dose rate, geometry function, dose radial function and anisotropy function. The results showed good agreement with the values published by the literature, for the same iodine- 125 model, this fact confirms that the realized parameters will be able to be used for the IPEN-CNEN iodine-125 seeds dosimetry and quality control. (author)

  10. Dosimetry of the stereotactic radiosurgery with linear accelerators equipped with micro multi-blades collimators; Dosimetria dos sistemas de radiocirurgia estereotaxica com aceleradores lineares equipados com colimadores micro multi-laminas

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Andre Mozart de Miranda

    2008-07-01

    In this work, absorbed dose to water produced by the radiation beam of a clinical linear accelerator - CLINAC 600C{sup TM} (Varian), with a photon beam of 6 MV, were evaluated both theoretically and experimentally. This determination includes square and circular field configurations, the last one obtained with a micro multi leaf collimator - mMLC m3{sup TM} (Brain Lab). Theoretical evaluation was performed throughout Monte Carlo method. Experimental measurements of Percentage Depth Dose - PDD and derived Tissue Maximum Ratio - TMR curves from CLINAC 600C were validated by comparison with reference values as well as with measurements using different detectors. The results indicate local differences smaller than 5% and average differences smaller than 1,5% for each evaluated field, if they are compared to the previous commissioning values (made in 1999) and to the values of literature. Comparisons of ionization chamber and diode result in an average local difference of -0,6% for PDD measurements, and within 1% for lateral dose profiles, at depth, in the flat region. Diode provides measurements with better spatial resolution. Current output factors of open fields agree with reference values within 1,03% of discrepancy level. Current absorbed dose distributions in water are, now, considered reference values and allow characterization of this CLINAC for patient dose calculation. The photon spectra resulting from simulations with PENELOPE and MCNP codes agree approximately in 80% of the sampled points, in what average energies of (1,6 {+-} 0,3)MeV, with MCNP, and of (1,72 {+-} 0,08)MeV, with PENELOPE, are coincident. The created simple source model of the CLINAC 600C, using the PENELOPE code, allows one to calculate dose distributions in water, for open fields, with discrepancies of the order of {+-} 1,0% in dose and of {+-} 0,1 cm in position, if they are compared to experimental measurements. These values met the initial proposed criteria to validate the simulation model and guarantee its applicability in dosimetric evaluations of radiotherapy with this CLINAC. The geometrical description of the mMLC m3 for Monte Carlo purposes, using the PENELOPE code, was considered satisfactory, providing the characterization of relevant physical parameters such as the transmission of the mMLC, within an estimated uncertainty of {+-} 0,2%, and the average under dose of (11,4 {+-} 2,0)%, due the tongue and groove effect, which is coincident with the experimental value of (12,5 {+-} 2,7)%, for this particular collimator design. The Monte Carlo simulation codes which combine a single source model of the CLINAC 600C with the full m3 model, allows to calculate dose distributions in water for conformal beams within the discrepancy level of {+-} 1%. However, output factors of conformal beams with the mMLC can be calculated with uncertainties varying from 1 to 3%, when they are compared to experimental results. These evaluated fields represent, and come close to treatment fields. The results of this work guarantee a better dosimetric knowledge of the micro multi leaf collimator m3, which is used in three-dimensional stereotactic radiotherapy and radiosurgery techniques. This provides a useful tool in the evaluation of the mMLC as well as the absorbed doses produced in complex field configurations.(author)

  11. Implementation of a dosimetry service for the occupationally exposed personnel of the ESFM-IPN; Implementacion de un servicio de dosimetria para el personal ocupacionalmente expuesto de la ESFM-IPN

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez A, Y. [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Barragan No. 779, Col. Narvarte, 03020 Mexico D. F. (Mexico); Sanchez R, A. A. [IPN, Escuela Superior de Fisica y Matematicas, U. P. Adolfo Lopez Mateos, Edif. 9, 07738 Mexico D. F. (Mexico); Ceron R, P. V.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia y Tecnologia Avanzada, Unidad Legaria, Av. Legaria No. 694, 11500 Mexico D. F. (Mexico); Vega C, H. R., E-mail: yamani.hernandez@cnsns.gob.mx [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    Because the ionizing radiations handling implies a risk for the health, is necessary to take a control of the radiation quantity that the occupationally exposed personnel receives during their daily work with ionizing radiations. For this purpose there are several types of dosimetry and companies that provide the service, but taking advantage that the Escuela Superior de Fisica y Matematicas del Instituto Politecnico Nacional (ESFM-IPN) possesses a thermoluminescence equipment (Tl) was decided to develop a personnel dosimetry service for gammas, with thermoluminescent glasses of type TLD-100. First one carries out a glasses characterization, for which the glasses were washed with a methyl alcohol solution, without rubbing them for not damaging them; after the drying, they were subjected to a temperature of 400 C during one hour and later on 100 grades C for two hours in order to erasing them the bottom information that they could have. 200 glasses were exposed to gamma radiation coming from a Cobalt 60 source property of ESFM-IPN in order to selecting the glasses that had a response whose precision was inside a standard deviation. Of this characterization 80 dosimeters were selected that had better response according to the obtained readings as well as of their shine curves. These selected TLD-100 glasses were irradiated to different dose of gamma radiation and with those readings it was built a dose response curve in m R against readings of electric load in pick Coulombs (pCou). The response curve was a direct line or calibration curve. As final exercise some glasses of this selected lot were subjected to irradiation dose not known by the person that carried out the readings and this way was proven that the results were appropriate with the calibration curve. Finally these dosimeters were placed in port-dosimeters and erased guides of dosimeters, of equipment use and dosimeters lecture were also elaborated. (Author)

  12. Pilot project for implantation of the National Commission on Radiation Protection and Dosimetry of CONTER, Brazil; Projeto piloto de implantação da Comissão Nacional de Radioproteção e Dosimetria do CONTER

    Energy Technology Data Exchange (ETDEWEB)

    Padilha Filho, L.G., E-mail: lucaspadilhaemec@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Santos, J.R.A.; Dmitruk, P.P.; Souza, J.H.C.; Hamann, J.H. [Conselho Nacional dos Técnicos e Tecnólogos em Radiologia (CONTER), Brasília, DF (Brazil); Soboll, D.S. [Universidade Tecnológica Federal do Paraná (UTFPR), Curitiba, PR (Brazil)

    2017-07-01

    This work presents the pilot project of the National Council of Technicians and Technologists in Radiology (CONTER), which created the National Commission on Radioprotection and Dosimetry (CNRD), in order to develop a radioprotection culture for professionals in radiographic techniques.

  13. Evaluation of the efficiency of different methods of personal dosimetry in vascular interventional radiology; Avaliação da eficiência de diferentes métodos de dosimetria pessoal em radiologia intervencionista vascular

    Energy Technology Data Exchange (ETDEWEB)

    Bacchim Neto, F.A., E-mail: fernando.bacchim@lnls.br [Laboratório Nacional de Luz Síncrotron (LNLS), Campinas-SP (Brazil). Centro Nacional de Pesquisa em Energia e Materiais; Alves, A.F.F.; Rosa, M.E.D. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Instituto de Biociências; Pina, D.R. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Departamento de Doenças Tropicais e Diagnóstico por Imagem

    2017-07-01

    Interventional Radiology - IR is the area of medicine that provides the largest occupational exposures. The dose values to which interventionists are exposed are difficult to standardize. The objective of the study is to perform a complete evaluation of occupational exposures and to determine the efficiency of different personal dosimetry methods used in IR. We evaluated the efficiencies of 6 different personal dosimetry methodologies used internationally to estimate the effective dose received by interventional professionals. And, based on this analysis, determine the characteristics of each methodology. One of the methods of personal dosimetry recommended by Brazilian legislation was the most conservative, overestimating, on average, the effective dose of professionals by up to 200%, reaching maximum values close to 400%. The most accurate method was that used in North America. This method did not overestimate the effective dose of the professionals more than a few percent and their standard deviation relative to the effective reference dose were the lowest. Based on these results, the choice of methodologies employing at least two dosimeters, one under and above protective aprons is recommended. In addition, in some situations where the dose in the hands may be high, additional dosimeters for this region are also recommended.

  14. L-alanine detector characterization for dosimetry of small fields in SBRT with VMAT techniques; Caracterizacao do detector de L-alanina para dosimetria de campos pequenos em SBRT com a tecnica de VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Mazaro, Sarah J.; Peres, Leonardo [Instituto Nacional de Cancer (INCA), Rio de Janeiro, RJ (Brazil); Baffa, Oswaldo, E-mail: sarahmazaro@yahoo.com.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Departamento de Fisica

    2016-07-01

    New radiotherapy treatment techniques have some problems such as: the dosimetric and geometric of the beam and small fields. Determination of the prescribed dose on the target volume in small fields is hampered due to lack of lateral electronic equilibrium and steep dose gradient along the edges of fields. The choice of radiation better detector becomes important in the dosimetry of small fields. Alanine detector has been shown to be a good choice for measurements of high doses of radiation in small fields. This study aims to characterize the L-alanine detector through the dosimetric tests for SBRT in VMAT techniques. L-alanine response showed a strong linear correlation with the dose (R ² = 0.9865), with significant angles and dose rate dependencies (14%) and (15%) respectively, and minor with the small field size (maximum 4% deviation). (author)

  15. Experiences in the continuous improvement of quality assurance of the dosimetry services of SLDC-MD-ININ; Experiencias en la mejora continua del aseguramiento de la calidad de los servicios de dosimetria de LSCD-ME-ININ

    Energy Technology Data Exchange (ETDEWEB)

    Tovar M, V. M.; Vergara M, F.; Perez M, V.; Anaya M, R.; Cejudo A, J.; Alvarez R, J. T.; Arenas O, A.; Cruz F, C., E-mail: victor.tovar@inin.gob.m [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Laboratorio Secundario de Calibracion Dosimetrica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-09-15

    From 2003 the Secondary Laboratory of Dosimetric Calibration (SLDC) of Metrology Department of Ionizing Radiations (MD), has complemented the Quality Manual of National Institute of Nuclear Research (ININ) according to the standard ISO 9001: 2000. However, due to that the National Center of Metrology of Mexico delegates its functions in the dosimetry and activity area for the field of the ionizing radiations to the ININ: one of the requirements so that the ININ has been designated as -Declared Institute- before the International Office of Weights and Measurements, it is to demonstrate before the Inter-American System of Metrology that the quality system of the SLDC fulfills the standard ISO/IEC 17025: 2005, satisfied this requirement the Inter-American System of Metrology in their meeting of evaluation of quality systems, Ottawa (2007) grants a certification document to the SLDC that guarantees their capacities of calibration measurements for dosimetry services. Concretely, inside the standard activities ISO 9000 with respect to the point 8 on measurement, analysis and improvement the Management of Quality Assurance of ININ carries out at year two interns auditing and every month is given continuation to the non conformities detected in the procedures that support the services of the SLDC for dosimetry with purposes of radiological protection and clinical dosimetry. (Author)

  16. Experience in the treatment of IMRT in prostate cancer. Planning, dosimetry and quality control; Experiencia en el tratamiento de IMRT en cancer de prostata. Planificacion, dosimetria y control de calidad

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Barrado, A.; Garcia Vicente, F.; Fernandez Bedoya, V.; Bermudez Luna, R.; Perez Gonzalez, L.; Torres Escobar, J. J.

    2011-07-01

    The aim of this study is to review the treatment of prostate cancer at our center. A description of the entire procedure, involving clinical dosimetry, and procedures for verification of treatment, including physical dosimetry and parallel computing system MSure (Standard Imaging, Inc., Middleton) as part of these procedures. This system is based on the model published by trifuente Yang et al. (Yang et al. 2002) for testing treatments regarding the number of monitor unit (MU) given. In addition, this software has a module for the testing of treatments for intensity modulated radiotherapy (IMRT), which will be analyzed in this study.

  17. Verification of dosimetry planning in brachytherapy in format Dicom and EUD calculation of Risk in bodies; Verificacion de la planificacion dosimetria en braquiterapia en formato Dicom y calculo del EUD en organos de riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Hernandez, M. J.; Sendon del Rio, J. R.; Ayala Lazaro, R.; Jimenez Rojas, M. R.; Gomez Cores, S.; Polo Cezon, R.; Lopez Bote, M. A.

    2013-07-01

    This work Describes a program that automates the verification of the schedules in brachytherapy (configuration and dosimetric treatment parameters) for sources of Ir-192 (mHDR v2) and Co-60 (Co0.A86) from the plan exported in DICOM format data. (Author)

  18. The comet assay as a dosimetric tool in evaluation of overexposure localized irradiation; El ensayo de cometa como herramienta de la dosimetria biologica en la evaluacion de sobreexposiciones fuertemente localizadas

    Energy Technology Data Exchange (ETDEWEB)

    Giorgio, Marina Di; Taja, Maria R.; Nasazzi, Nora [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); Bustos, Norma; Cavalieri, Hernan; Bolgiani, Alberto [Fundacion Fortunato Benaim, Buenos Aires (Argentina)

    2001-07-01

    With inhomogeneous exposures, as is characteristic in accidents, the skin may be an important organ in determining clinical prognosis, being dosimetric assessment a necessary requirement. In order to get information to be applied on the evaluation of skin biopsies without culture for an early assessment of irradiation consequences in locally irradiated individuals, contributing with the biophysical techniques, we evaluate the alkaline comet assay (for doses < 5 Gy) as a method for the detection of DNA radiation induced damage in keratinocytes from primary and secondary cultures obtained from medium thickness skin biopsies and epidermal cells, without culture, derived from the same sample of skin biopsies of patients requiring grafts. To extend the dose range (> 5 Gy), neutral comet assay was applied to keratinocytes from primary and secondary cultures and to a suspension of epidermal cells obtained from biopsies irradiated in vitro an afterwards processed to obtain the mentioned cellular suspension, in order to reproduce the closest condition to in vivo overexposure. The correlation of the obtained data with factors of the patient and the corresponding skin graft response, were evaluated. (author)

  19. Intercalibration of radiological measurements for surveillance purposes of the internal dosimetry laboratory coordinated by the IAEA; Intercalibracion de mediciones radiologicas para fines de vigilancia del laboratorio de dosimetria interna coordinada por el OIEA

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2002-07-15

    The ININ of Mexico participated in this intercomparison organized by the IAEA in 2000. The objective of this activity is that the dosimetry laboratories that participate can validate the programs of internal dosimetry, with the purpose of improving its capacity in the evaluation of the internal dose and have access to a mechanism to evaluate its dosimetry system under real conditions. The specific objectives of this intercomparison were: 1. To evaluate the participant's capacity to manage the measurements of individual monitoring in terms of the activity in the phantom. 2. To provide the access to the unique calibration resources that otherwise would not be available. 3. To compare the operation of several detection systems, the geometry, phantoms, calibration methods and methods for the evaluation of activity of the radionuclide used by each institution. 4. To provide the independent verification of the direct measurement methods of the dosimetry service. (Author)

  20. Vivo dosimetry using TLD detectors in prostate seed implants of I-125: preliminary results; Dosimetria in vivo mediante detectores de TLD en implantes de prostata con semillas de I-125: resultados preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Reyes, A.; Pedro, A.; Bassas, P.; Duch, M. A.; Cros, M.; Mane, S.

    2011-07-01

    We present preliminary results of a new in vivo dosimetry technique that could allow to know immediately after implantation of the prostate if the dose distribution determined by the scheduler is similar to the actual dose measured with TLD detectors.

  1. Evaluation of the response of thermoluminescent detectors in clinical beams dosimetry using different phantoms; Avaliacao da resposta de detectores termoluminescentes na dosimetria de feixes clinicos utilizando diferentes objetos simuladores

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, Luciana Cardoso

    2010-07-01

    Radiotherapy is one of the three principal treatment modalities used in the treatment of malignant diseases such as cancer, the other two are chemotherapy and radiosurgery. In contrast to other medical specialties that rely mainly on the clinical knowledge and experience of medical specialists, radiotherapy, with its use of ionizing radiation in treatment of cancer, relies heavily on modern technology and the collaborative efforts of several professionals whose coordinated team approach greatly influences the outcome of the treatment. In the area of clinical dosimetry, an efficient and accurate calibration of the radiation beam ensures knowledge of the radiation dose delivered to the patient, allowing thus the success of radiotherapy. This study aims to compare the thermoluminescent response of calcium sulfate doped with dysprosium (CaSO{sub 4}:Dy) dosimeters produced by IPEN (6 mm in diameter and 0,8 mm tick) with the response of lithium fluoride (3,15 x 3,15 x 0,9 mm{sup 3}) doped with magnesium and titanium (LiF:Mg,Ti) in dosimetry of clinical photons (6 and 15 MV) and electrons beams (6 and 9 MeV) using solid water (RMI-457), water and PMMA phantoms. Initially, the dose-response curves were obtained for irradiation in cobalt-60 gamma radiation source in air (PMMA plates) and under electronic equilibrium conditions and for clinical electrons and photons beams at depth of maximum dose. The sensitivities of the thermoluminescent dosimeters were also evaluated and the values of their reproducibilities and intrinsic efficiency were determined for the response to different types of phantoms and radiation energy. The obtained results indicate that the main advantage of CaSO{sub 4}:Dy dosimeters is the enhanced sensitivity to radiation doses measured for {sup 60}Co, photons and electrons beams, thus representing a viable alternative for application in dosimetry in the radiotherapy area. (author)

  2. Dosimetry in non-homogeneous media with alanine/EPR mini dosemeters and simulation with PENELOPE Monte Carlo code;Dosimetria em meios nao-homogeneos com minidosimetros de alanina/EPR e simulacao Monte Carlo com o codigo PENELOPE

    Energy Technology Data Exchange (ETDEWEB)

    Vega Ramirez, J.L.; Chen, F.; Nicolucci, P.; Baffa, O. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica e Matematica

    2009-07-01

    The dosimetric system of L-alanine mini dosimeter and K-Band EPR spectrometer was tested for the dosimetry in non-homogeneous media through the determination of the Percentage Depth Dose (PDD) curve for a small radiation field. The alanine mini dosimeters were produced by mechanical pressure of a mixture of L-alanine (95%) and PVA (5%) to nominal dimensions of 1 mm diameter and 3 mm length and 3 - 4 mg. For detecting the EPR signal of the mini dosimeters irradiated to 25 Gy, a K-Band (24 GHz) spectrometer was used. The dosimeters were irradiated in a {sup 60}Co radiotherapy unit using 80 cm source skin distance and field sizes of 2.5 x 2.5 cm{sup 2}. The inhomogeneous phantom consisted of acrylic and cork sheets of 30 x 30 x 1 cm{sup 3}; six cork sheets were sandwiched between five and nine acrylic sheets, which were placed at the top and bottom regions respectively. PDD curves with radiographic film and PENELOPE simulation were also determined. The PDD results for alanine mini dosimeters agreed better than 5.9% with film and PENELOPE. (author)

  3. Development of a pediatric chest phantom for dosimetry in computerized tomography; Desenvolvimento de objeto simulador de tórax pediátrico para dosimetria em tomografia computadorizada