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Sample records for dosimetria osl luminescencia

  1. 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; Aplicacao das tecnicas de dosimetria termoluminescente (TL) e luminescencia opticamente estimulada (OSL) na determinacao de curvas de isodose em uma simulacao de tratamento de cancer pela tecnica de radioterapia em arco modulado volumetrico - VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, Amanda

    2015-07-01

    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{sub 4}:Dy and Al{sub 2}0{sub 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{sup 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)

  2. 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)

  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. OSL and thermally assisted OSL response in dental enamel for its possible application in retrospective dosimetry.

    Science.gov (United States)

    Soni, Anuj; Mishra, D R; Polymeris, G S; Bhatt, B C; Kulkarni, M S

    2014-11-01

    Dental enamel was studied for its thermoluminescence (TL) and optically stimulated luminescence (OSL) defects. The TL studies showed a wide glow curve with multiple peaks. The thermally assisted OSL (TA-OSL) studies showed that the integrated TA-OSL and thus OSL signal increases with readout temperature between 100 and 250 °C, due to the temperature dependence of OSL. The thermally assisted energy E A associated with this increase is found to be 0.21 ± 0.015 eV. On the other hand, the signal intensity decreases with temperature between 260 and 450 °C. This decrease could be due to depletion of OSL active traps or possible thermal quenching. The increase of the OSL signal at increased temperature can be used to enhance the sensitivity of dental enamel for ex vivo measurements in retrospective dosimetry. The emission and excitation spectra of its luminescence centers were studied by photoluminescence and were found to be at 412 and 324 nm, respectively. It was found to possess multiple OSL active traps having closely lying photoionization cross sections characterized by continuous wave OSL and nonlinear OSL methods. The investigated dental enamel samples showed a linear OSL dose response up to 500 Gy. The dose threshold was found to be 100 mGy using a highly sensitive compact OSL reader with blue LED (470 nm) stimulation.

  9. 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 t...

  10. Tl and OSL on diopside crystal

    Energy Technology Data Exchange (ETDEWEB)

    Cano, N.F.; Watanabe, S. [Institute of Physics, University of Sao Paulo, CP 66318, 05315-970, Sao Paulo (Brazil); Mittani, J.C.R.; Yukihara, E.G. [Department of Physics, Oklahoma State University, Stillwater, OK 74078 (United States)

    2006-07-01

    The diopside with chemical composition CaMgSi{sub 2}O{sub 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{sub 2} (55.81 % mol), CaO (23.47 % mol), MgO (18.03 % mol), Al{sub 2}O{sub 3} (1.56 % mol), Fe{sub 2}O{sub 3} (0.53 % mol), K{sub 2}O (0.44 % mol), TiO{sub 2} (0.065 % mol), P{sub 2}O{sub 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)

  11. 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

    The factors which affect the shape of Optically Stimulated Luminescence (OSL) decay curves are examined, both experimentally and theoretically, in an effort to understand and describe the behavior of OSL as a function of temperature. The processes considered include: (1) retrapping by shallow traps...

  12. Analysis of TL and OSL kinetics of lithium aluminate

    CERN Document Server

    Twardak, A; Marczewska, B; Gieszczyk, W

    2014-01-01

    Lithium aluminate (LiAlO2) polycrystalline material showing high OSL sensitivity and linear dose response was prepared at IFJ Krakow. The kinetic parameters of OSL and TL processes were evaluated using various experimental techniques: LM-OSL deconvolution, TL glow-curve deconvolution, variable heating rate and isothermal decay. The OSL signal was found to consist of four components, one of them exhibiting a very slow decay. The TL glow-curve possesses two apparent peaks at approximately 85 oC and at 165 oC, which both seem to follow first order kinetics. These peaks seem to have a composite structure and as many as six peaks were found in the glow-curve.

  13. OSL studies of local bricks for retrospective dosimetric application

    Science.gov (United States)

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

    2016-09-01

    Luminescence properties of quartz extracted from bricks has been reported worldwide for its use in dose estimation in case of nuclear or radiological accident. Accordingly, in this study the feasibility of utilizing the optically stimulated luminescence (OSL) emission of quartz extracted from red bricks collected from three different locations in and around Mumbai, India for retrospective dosimetry was explored. Thermoluminescence and OSL characterization of the samples were carried out. The growth curve, thermal stability and equivalent dose plateau of the OSL signal suggested the signals to be well behaving. Subsequently, the dose recovery tests carried for different administered doses, using single aliquot regenerative protocol, demonstrated the feasibility of the OSL emissions of these samples for dose evaluation in retrospective dosimetry.

  14. OSL-thermochronometry using bedrock quartz: A note of caution

    NARCIS (Netherlands)

    Guralnik, B.; Ankjærgaard, C.; Jain, M.; Murray, A.S.; Müller, A.; Walle, M.; Lowick, S.E.; Preusser, F.; Rhodes, E.J.; Wu, T.S.; Mathew, G.; Herman, F.

    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 bo

  15. Studying CaSO4:Eu as an OSL phosphor

    Science.gov (United States)

    Guckan, Veysi; Altunal, Volkan; Nur, Necmettin; Depci, Tolga; Ozdemir, Adnan; Kurt, Kasim; Yu, Yan; Yegingil, Ihami; Yegingil, Zehra

    2017-09-01

    This study was carried out to investigate the properties of the OSL signal from Eu-doped calcium sulfate (CaSO4:Eu) phosphor and study on its thermal behavior as a function of temperature under a series of luminescence experiments. The suitability of its usage as an optically stimulated luminescence (OSL) dosimeter was also checked. CaSO4:Eu was synthesized using the precipitation method and prepared in pellet form. The dopant concentration value was performed as 0.1 mol%. The synthesized CaSO4:Eu was analyzed by X-ray diffraction (XRD) method to confirm the product. To have an idea about the crystallography and microstructure morphology of the material, scanning electron microscope (SEM) analysis were carried out. It was found that the OSL signal is a resultant signal having three components and exhibits thermal quenching above 150 °C. The excitation spectrum of CaSO4:Eu showed different peaks in the region 220-360 nm with the highest one at 269 nm. Thermoluminescence (TL) signals of CaSO4:Eu pellets were obtained and compared with the TL signals obtained after OSL measurements of the same pellets by blue light stimulation. The low temperature peak near 180 °C did not show any significant change in TL after OSL measurement whereas the high temperature peak at 240 °C was bleached with the blue light illumination and might be responsible for the observed OSL signal. The dosimetric properties such as dose response, minimum detectable dose, energy response, reusability, fading properties, thermal stability and effect of reading temperatures on OSL signals were examined. OSL signals of CaSO4:Eu pellets were decreased by approximately 8% at the end of the 24 h and by about 7% at the end of 28 days when compared with the first readout. The thermal stability of the ∼240 °C TL peak and OSL signal using isothermal decay measurements were used to determine the trap parameters. The CaSO4:Eu OSL dosimeter in accordance with the presented study allows a high

  16. 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...... sensitivity changes during SAR measurements. It is found that, in contrast to the test dose OSL, the TT-OSL response to a test dose can successfully monitor sensitivity changes, and a high-temperature blue-light bleach (600s at 260°C) in the middle of each SAR cycle is necessary to minimize interference...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    , 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...

  18. Firing temperature of pottery using TL and OSL techniques

    Energy Technology Data Exchange (ETDEWEB)

    Polymeris, G.S. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Physics Department, Aristotle University of Thessaloniki, University Campus, Thessaloniki GR-54124 (Greece); Sakalis, A. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Papadopoulou, D. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Department of Science, School of Technological Applications, Technological Educational Institute of Kavala, Agios Loukas, Kavala 65404 (Greece); Dallas, G. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Department of Electrical and Computer Engineering, Democritus University of Thrace, Xanthi GR-67100 (Greece); Kitis, G. [Physics Department, Aristotle University of Thessaloniki, University Campus, Thessaloniki GR-54124 (Greece); Tsirliganis, N.C. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece)], E-mail: tnestor@ceti.gr

    2007-09-21

    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.

  19. Characterisation of OSL and OSLN droplets for dosimetry.

    Science.gov (United States)

    Nascimento, L F; D'Agostino, E; Vaniqui, A C S; Saldarriaga, C; Vanhavere, F; De Deene, Y

    2014-10-01

    In spite of considerable progress in neutron dosimetry, there is no dosemeter that is capable of measuring neutron doses independently of the neutron spectrum with good accuracy. Carbon-doped aluminium oxide (Al2O3:C) is a sensitive material for ionising radiation (beta-ray, X ray and electron) and has been used for applications in personal and medical dosimetry as an optically stimulated luminescence (OSL) dosemeter. Al2O3:C has a low sensitivity to neutron radiation; this prevents its application to neutron fields, representing a disadvantage of Al2O3:C-OSL when compared with LiF, which is used as a thermoluminescent detector. Recently an improvement for neutron dosimetry (Passmore and Kirr. Neutron response characterisation of an OSL neutron dosemeter. Radiat. Prot. Dosim. 2011; 144: 155-60) uses Al2O3:C coated with (6)Li2CO3 (OSLN),which gives the high-sensitive response as known for Al2O3:C with the advantage of being also sensitive to thermal neutrons. In this article, the authors compare small-size detectors (droplets) of Al2O3:C (OSL) and of Al2O3:C+(6)Li2CO3 (OSLN) and discuss the advantages and drawbacks of both materials, regarding size vs. response.

  20. Firing temperature of pottery using TL and OSL techniques

    Science.gov (United States)

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

    2007-09-01

    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.

  1. 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

    is known as linear modulation OSL (LM-OSL). In controlled laboratory conditions, this technique has been employed to study the ease-of-bleaching of the trapped charge in quartz by comparing the OSL curves of quartz aliquots which have been either: (1) fully bleached, followed by a laboratory dose of beta...... -irradiation, or (2) partially bleached, followed by the laboratory beta -dose. The ratio of the OSL signals due to the beta -dose from the partly and fully bleached aliquots is illustrated to be a potential indicator of the degree of optical resetting of the OSL signal in dating material. The key parameter...

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

    Science.gov (United States)

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

    2017-04-01

    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. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 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)

  4. Sand and soil dynamics studied by quartz OSL dating

    Science.gov (United States)

    Wallinga, J.; Schilder, M.; van Mourik, J.

    2012-04-01

    Landscape evolution is the result of altering periods with active geomorphological processes and relatively stable periods with soil development. Soils and buried soils in polycyclic profiles are important indicators of landscape stability. Buried soils as micropodzols in polycyclic driftsand sequences are a common phenomena in driftsand landscapes. Insight in the age of the buried soils is of paramount importance to determine whether they indicate local or regional phases of landscape stability. However, accurate datingof palaeosols is often problematic. Here we investigate the use of optically stimulated luminescence (OSL) dating for determining the time, available for soil formation and duration of palaeosol formation. We studied young drift-sand deposits in the Weerterbergen area in SE-Netherlands. Samples were taken from six shallow pits (hearths in the area. Combining this information with the OSL ages made clear that some of the 'palaeosols' consisted of wind-blown material only and did not reflect a landscape stability phase.

  5. Apparatus And Method For Osl-Based, Remote Radiation Monitoring And Spectrometry

    Science.gov (United States)

    Miller, Steven D.; Smith, Leon Eric; Skorpik, James R.

    2006-03-07

    Compact, OSL-based devices for long-term, unattended radiation detection and spectroscopy are provided. In addition, a method for extracting spectroscopic information from these devices is taught. The devices can comprise OSL pixels and at least one radiation filter surrounding at least a portion of the OSL pixels. The filter can modulate an incident radiation flux. The devices can further comprise a light source and a detector, both proximally located to the OSL pixels, as well as a power source and a wireless communication device, each operably connected to the light source and the detector. Power consumption of the device ranges from ultra-low to zero. The OSL pixels can retain data regarding incident radiation events as trapped charges. The data can be extracted wirelessly or manually. The method for extracting spectroscopic data comprises optically stimulating the exposed OSL pixels, detecting a readout luminescence, and reconstructing an incident-energy spectrum from the luminescence.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.L., E-mail: wxl@loess.llqg.ac.cn [SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 (China); Key Laboratory of Western Mineral Resources and Geological Engineering, Ministry of Education of China and Chang’an University, Xi’an 710054, Shaanxi (China); Du, J.H. [SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 (China); Key Laboratory of Western Mineral Resources and Geological Engineering, Ministry of Education of China and Chang’an University, Xi’an 710054, Shaanxi (China); Adamiec, G. [Silesian University of Technology, Institute of Physics—Centre for Science and Education, ul. Konarskiego 22B, 44-100 Gliwice (Poland); Wintle, A.G. [Institute of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB (United Kingdom); McDonald Institute for Archaeological Research, University of Cambridge, Downing Street, Cambridge CB2 3ER (United Kingdom)

    2015-03-15

    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.

  7. 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%.

  8. 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)

  9. Investigation of OSL signals from very deep traps in unfired and fired quartz samples

    Energy Technology Data Exchange (ETDEWEB)

    Kitis, G. [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, Thessaloniki (Greece); Kiyak, N.G. [ISIK University, Physics Department, Faculty of Science and Arts, 34980 Sile, Istanbul (Turkey); Polymeris, G.S. [ISIK University, Physics Department, Faculty of Science and Arts, 34980 Sile, Istanbul (Turkey); Cultural and Educational Technology Institute - R.C. Athena/Archaeometry Laboratory, Xanthi (Greece); Pagonis, V., E-mail: vpagonis@mcdaniel.ed [McDaniel College, Physics Department, Westminster, MD 21157 (United States)

    2010-03-15

    This paper presents an attempt to isolate experimentally optically stimulated luminescence (OSL) signals which may originate from very deep traps (VDT) in quartz samples. As VDT we consider those traps which are responsible for TL glow peaks with a peak maximum temperature above a TL readout temperature of 500 deg. C. The basic experimental procedure used to isolate OSL signals from VDT is heating the quartz samples to 500 deg. C immediately before measuring the OSL signal. The study was carried out on eight quartz samples of very different origins; it is found that all eight samples exhibit OSL signals from VDT, and for a wide region of OSL stimulation temperatures. The OSL signal from VDT depends strongly on the type of quartz sample studied and on whether the sample was fired at high temperatures or not. The behavior of the OSL signal from VDT as a function of the stimulation temperature is found to be very different in fired and unfired samples. The thermal activation energy E for the OSL signals from VDT is obtained in both fired and unfired samples. The OSL signal from VDT in quartz samples fired at 800 deg. C for 1 h is very high, and the OSL curves consist of three well-defined components and a fourth slow component which is rather poorly resolved. The dose response of these components is obtained using a computerized deconvolution procedure for the dose region 0.5-300 Gy. The results are of importance for dating of ancient fired ceramics, since OSL signals from VDT could potentially extend appreciably the equivalent dose region toward both lower and higher values.

  10. Developpement and performance testing of a time-resolved OSL measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Duk Geun [Dept. of Physics, Kangwon National University, Chuncheon (Korea, Republic of); Kim, Myung Jin [Radiation Research Institute, Neosiskorea Co., Ltd., Daejeon (Korea, Republic of)

    2017-03-15

    Time-resolved optically stimulated luminescence (TR-OSL) is a very useful method for calculating the lifetimes of crystalline quartz and feldspar. A compact TR-OSL system was developed, comprising a heater assembly manufactured using Kanthal wire, 2 powerful blue light-emitting diodes (LED, LXHL-PB02) for optical stimulation equipped with VIS liquid light guides, and a photomultiplier tube combined with an optical filter for luminescence detection. A pulse generated from the data acquisition board (NI PCI 6250) was used to initiate on/off signals in LED and TR-OSL measurements. The TR-OSL and background signals measured using this TR-OSL system using quartz samples were very similar to those reported in a previous study. Additionally, the lifetimes of the build-up and TR-OSL signals were calculated as 27.4±2.2 μs and 30.3±0.6 μs, respectively, in good agreement with the findings of a previous study. It was concluded that the developed TR-OSL system was very reliable for TR-OSL signal measurements and lifetime calculations.

  11. 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

    Quartz extracted from heated bricks has been previously suggested for use in dose estimation in accident dosimetry, but this technique has never been applied before to Japanese quartz which often has unusual OSL characteristics. In this study the optically stimulated luminescence (OSL) characteri...

  12. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Yukihara, E.G. [Department of Physics, Oklahoma State University, Stillwater, OK 74078 (United States)], E-mail: eduardo.yukihara@okstate.edu; Mittani, J.; McKeever, S.W.S. [Department of Physics, Oklahoma State University, Stillwater, OK 74078 (United States); Simon, S.L. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-7238 (United States)

    2007-07-15

    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.

  14. 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 recently developed single grain attachment for the Riso TL-OSL reader has been modified to achieve linearly modulated optically stimulated luminescence (LM-OSL). Three different types of luminescence behaviour were observed in 81 quartz grains measured. These types are those showing only the ...

  15. Impact of firing on the OSL luminescence properties of natural quartz: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Koul, D.K., E-mail: dkkoul@barc.gov.in [Radiological and Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Polymeris, G.S. [Institute of Nuclear Sciences, Tandogan Campus, 06100 Beşevler, Ankara (Turkey); Soni, A.; Kulkarni, M.S. [Radiological and Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2016-03-01

    A comprehensive study was carried out to observe the impact of firing on the behavior of different features of the optically stimulated luminescence (OSL) signal of geological quartz. The different features which could influence its use in different applications were studied. A comparison of nature of (i) thermoluminescence (TL) glow curves, (ii) OSL decay curves, (iii) pulse annealing curves, (iv) fast and slow components and (v) thermally transferred OSL (TT-OSL) emission of unfired and fired samples suggested a profound influence of thermal firing on the OSL signal. The composition of the OSL signal was seen to get altered by firing treatment; the magnitude of slow component losing its dominance to the fast component. This was true of pulse annealing also, the fired curve looked different from the unfired one. TT-OSL was observed to be larger in unfired sample as compared to the fired sample. Finally, firing was seen to enable reliable dose recovery using single aliquot regenerative (SAR) method, which has not been the case with the unfired sample studied here.

  16. Investigating the resetting of OSL signals in rock surfaces

    DEFF Research Database (Denmark)

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

    2011-01-01

    There are many examples of buried rock surfaces whose age is of interest to geologists and archaeologists. Luminescence dating is a potential method which can be applied to dating such surfaces; as part of a research project which aims to develop such an approach, the degree of resetting of OSL...... signals in grains and slices from five different cobbles/boulders collected from a modern beach is investigated. All the rock surfaces are presumed to have been exposed to daylight for a prolonged period of time (weeks to years). Feldspar was identified as the preferred dosimeter because quartz extracts...... 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...

  17. Temperature coefficients for in vivo RL and OSL dosimetry using Al2O3 : C

    DEFF Research Database (Denmark)

    Andersen, C.E.; Edmund, Jens Morgenthaler; Damkjaer, S.M.S.

    2008-01-01

    A radiotherapy dosimetry system based on radiolurninescence (RL) and optically stimulated luminescence (OSL) from small carbon-doped aluminum oxide (Al2O3:C) crystals attached to optical-fiber cables has been developed. To quantify the influence of temperature variations on clinical RL and OSL...... measurement results, we conducted an automated laboratory experiment involving threefold randomization of (1) irradiation temperature (10-45 degrees C), (2) stimulation temperature (10-45 degrees C), and (3) irradiation dose (0-4 Gy; 50 kV X-rays). We derived linear RL and OSL temperature coefficients using...

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

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, Daniela Piai; Caldas, Linda V.E., E-mail: dpgroppo@usp.br [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    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 ({sup 90}Sr+{sup 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)

  20. Crushing effects on TL and OSL on quartz: relevance to fault dating

    Energy Technology Data Exchange (ETDEWEB)

    Toyoda, S. E-mail: toyoda@dap.ous.ac.jp; Rink, W.J.; Schwarcz, H.P.; Rees-Jones, J

    2000-12-15

    The effect of crushing on the TL and OSL signals in quartz was investigated to examine the feasibility of using OSL and TL for dating of faulted rocks. 275 deg. C TL signals were not reduced by crushing by hand (mortar and pestle), in a pellet die press, or using an automatic mortar and pestle, but the sensitivity of the 100 deg. C TL signal to a test dose decreased in crushed samples. Green light-stimulated OSL signal intensities were not decreased after crushing, but showed strongly increased inter-aliquot variability after crushing. We concluded that OSL and TL in quartz might be useful to characterize the crushing history of quartz in fault rocks, but their usefulness in dating fault events was not evident because we did not find evidence of signal zeroing under the conditions used in this study.

  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.

  2. Fundamentals of materials, techniques and instrumentation for OSL and FNTD dosimetry

    Science.gov (United States)

    Akselrod, M. S.

    2013-02-01

    The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al2O3:C as a material of choice for many dosimetric applications including fiberoptic OSL/RL sensors with diameters as small as 300 μm. A new RL/OSL fiberoptic system has a high potential for in vivo and in vitro dosimetry in both radiation therapy and diagnostic mammography. Different aspects of instrumentation, data processing algorithms, post-irradiation and real-time measurements are described. The next technological breakthrough was done with Fluorescent Nuclear Track detectors (FNTD) that has some important advantages in measuring fast neutron and high energy heavy charge particles that became the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology were engineered and successfully demonstrated for occupational and accident dosimetry, for medical dosimetry and radiobiological research.

  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 ca...... dose used and the natural dose. However, the sensitivity changes appear only weakly dependent upon added dose, suggesting that the SARA single aliquot technique may be a suitable method to overcome the sensitivity changes. (C) 1997 Elsevier Science Ltd.......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. Characteristics of thermally transferred optically stimulated luminescence (TT-OSL) in quartz and its potential for dating sediments

    Energy Technology Data Exchange (ETDEWEB)

    Tsukamoto, Sumiko [Institute of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB (United Kingdom); Duller, Geoff A.T. [Institute of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB (United Kingdom)], E-mail: ggd@aber.ac.uk; Wintle, Ann G. [Institute of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB (United Kingdom)

    2008-08-15

    The temperature dependence, dose response and bleaching characteristics of the thermally transferred optically stimulated luminescence (TT-OSL) of sedimentary quartz were studied, in order to assess the potential of the TT-OSL signal for dating. The TT-OSL was separated into two components; recuperated OSL (ReOSL) and basic transfer (BT-OSL) by annealing samples at 300 deg. C for 10 s as suggested in an earlier study. Four quartz extracts were studied, two from loess from China and two from coastal sands from South Africa. The equivalent doses of the two recent samples (one sand and one loess) were {approx}15Gy and this suggests that the signal can be bleached by sunlight but may not be totally zeroed. The sensitivity-corrected ReOSL from the older samples did not reach zero and gave doses of 14 and 52 Gy, respectively, after 7 days bleaching with a solar simulator. A single aliquot regenerative dose (SAR) protocol using ReOSL was proposed and tested. In this protocol, a blue light stimulation at 280 deg. C for 100 s at the end of each cycle resulted in the recovery of identical sensitivity-corrected ReOSL values, in spite of {approx}20 -30% loss in sensitivity for the four samples that were tested. Two dose response curves were constructed using the sensitivity-corrected ReOSL, one for the initial 2 s signal and the other for the fast component obtained by curve fitting. Using the additional high temperature bleach and the separated fast component of the ReOSL, it was possible to recover given doses within 10%, up to {approx}1000Gy for the loess and {approx}2000Gy for the coarse grained quartz. However, the natural dose obtained for the older sand was twice that obtained using the conventional SAR OSL method.

  5. 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.

  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

    (AMS) dates constrain these OSL ages. Quartz extracted from seven OSL samples from each of the cores was measured using both single-grain and multi-grain OSL techniques. Three of the single-grain natural dose distributions appear to be well bleached, but the others appear to be incompletely bleached...... incomplete bleaching is probably less important than postdepositional mixing and mixing during sampling. As a result, the burial age is probably best estimated using the weighted average of the individual single-grain dose estimates. The application of multi-grain OSL techniques to these samples results...

  7. OSL dating of Glacial Sediments from New Zealand and Olympic Mountains: Using Stratigraphy to our Advantage

    Science.gov (United States)

    Rittenour, T. M.; Thackray, G. D.; Shulmeister, J.

    2012-12-01

    Optically stimulated luminescence (OSL) dating provides an age estimate for the last time sediment was exposed to light. In glacial environments solar resetting of the luminescence signal prior to deposition is not assured and can lead to significant age overestimates. Sediments derived from glacial settings also commonly have other deleterious properties such as weak quartz luminescence signals, feldspar contamination and high levels of electron thermal transfer. Despite these potential problems, OSL commonly provides the only means to date glacial deposits due to limited material for radiocarbon and/or surface exposure dating, discrepancies between the age of a landform and the targeted underlying sediment, or deposit age beyond the range for radiocarbon. As part of a larger project to reconstruct MIS 3/4 glacial chronologies, OSL samples were collected from the Rangitata and Clutha River basins along the eastern Southern Alps, New Zealand and from the Hoh and Queets River basins, western Olympic Mountains, Washington USA. Samples for quartz OSL dating were collected from carefully selected shallow-water and well-sorted facies of glaciofluvial and glaciolacustrine sediments to select sediments most likely to have been exposed to light prior to deposition. OSL dating is preferred over other dating methods in the study areas because evidence for multiple pre-LGM glaciations is commonly preserved as buried and over-run packages of diamicton, outwash and lacustrine sediment, excluding application of surface-exposure techniques. Further, where the sediments are in fact associated with surficial landforms, detailed description of the underlying stratigraphy permits interpretation of the glacial processes at work and thus provides a more thorough understanding of the relevance of the ages to the advance. Results indicate that while some samples contain evidence for partial bleaching, most show symmetric equivalent dose distributions, and ages are in stratigraphic order

  8. 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...

  9. Relative TL and OSL efficiency to protons of various dosimetric materials.

    Science.gov (United States)

    Sądel, M; Bilski, P; Swakoń, J

    2014-10-01

    Thermoluminescence (TL) and optically stimulated luminescence (OSL) are the well-known phenomena used for passive methods of dose measurements. TL and OSL detectors are frequently used in the dosimetry of cosmic radiation in space and of particle radiotherapy beams. However, the relative TL/OSL efficiency, which is defined as a ratio of the emitted light intensity per unit dose for a given radiation type, to the same quantity for the reference gamma radiation is not constant and depends on radiation type and energy. In the present work several types of TL and OSL dosimetric materials, including lithium fluoride (LiF), aluminium oxide, beryllium oxide and lithium aluminate, were tested with protons. The measurements were realised exploiting the 60-MeV proton beam of the AIC-144 cyclotron in the Proton Eye Radiotherapy Facility at Institute of Nuclear Physics (IFJ PAN). The influence of proton energy on the relative efficiency and other TL/OSL characteristics of the studied detector types was presented. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Correlation between TL and OSL properties of CaF{sub 2}:N

    Energy Technology Data Exchange (ETDEWEB)

    Polymeris, George S. [Cultural and Educational Technology Institute (CETI), R.C. ' Athena' , Archaeometry Laboratory, Tsimiski 58, GR-67100 Xanthi (Greece) and Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece)]. E-mail: polymers@auth.gr; Kitis, George [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece); Tsirliganis, Nestor C. [Cultural and Educational Technology Institute (CETI), R.C. ' Athena' , Archaeometry Laboratory, Tsimiski 58, GR-67100 Xanthi (Greece)

    2006-09-15

    Natural CaF{sub 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.

  11. Independent evaluation of optically stimulated luminescence (OSL) 'dot' dosemeters for environmental monitoring.

    Science.gov (United States)

    Timilsina, Bindu; Gesell, Thomas F

    2011-01-01

    Optically stimulated luminescence (OSL) 'dot' dosemeters (manufactured by Landauer®) are reported to have a high degree of environmental stability, high level of sensitivity and provide wide range of dose measuring capabilities from 0.05 mGy to 100 Gy. The optical read out method is fast and relatively simple and permits repeated read out, but few studies have been performed about its application in monitoring radiation in the environment. This study was initiated to independently test the performance of OSL dot dosemeters for the application of measuring doses of radiation in the outdoor environment. Testing was performed in the laboratory to evaluate reproducibility and stability and in the field to evaluate accuracy relative to calibrated high-pressure ionisation chambers. The results showed that OSL dot dosemeters had good reproducibility and stability in both laboratory and field tests and met the performance requirements of standards of the American National Standards Institute.

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

    Energy Technology Data Exchange (ETDEWEB)

    Rink, W.J.; Toyoda, S.; Rees-Jones, J.; Schwarcz, H.P. [School of Geography and Geology, McMaster University, Hamilton, ON (Canada)

    1999-02-01

    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 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.

  13. Entrance surface dose measurements using a small OSL dosimeter with a computed tomography scanner having 320 rows of detectors.

    Science.gov (United States)

    Takegami, Kazuki; Hayashi, Hiroaki; Yamada, Kenji; Mihara, Yoshiki; Kimoto, Natsumi; Kanazawa, Yuki; Higashino, Kousaku; Yamashita, Kazuta; Hayashi, Fumio; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

    2017-03-01

    Entrance surface dose (ESD) measurements are important in X-ray computed tomography (CT) for examination, but in clinical settings it is difficult to measure ESDs because of a lack of suitable dosimeters. We focus on the capability of a small optically stimulated luminescence (OSL) dosimeter. The aim of this study is to propose a practical method for using an OSL dosimeter to measure the ESD when performing a CT examination. The small OSL dosimeter has an outer width of 10 mm; it is assumed that a partial dose may be measured because the slice thickness and helical pitch can be set to various values. To verify our method, we used a CT scanner having 320 rows of detectors and checked the consistencies of the ESDs measured using OSL dosimeters by comparing them with those measured using Gafchromic™ films. The films were calibrated using an ionization chamber on the basis of half-value layer estimation. On the other hand, the OSL dosimeter was appropriately calibrated using a practical calibration curve previously proposed by our group. The ESDs measured using the OSL dosimeters were in good agreement with the reference ESDs from the Gafchromic™ films. Using these data, we also estimated the uncertainty of ESDs measured with small OSL dosimeters. We concluded that a small OSL dosimeter can be considered suitable for measuring the ESD with an uncertainty of 30 % during CT examinations in which pitch factors below 1.000 are applied.

  14. 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

    While reviews of comparisons between multi-grain OSL ages and independent chronological information are available in the literature, there is hardly any such performance test for single-grain OSL ages. And yet, this is all the more needed as the interpretation of single-grain dose distributions r...

  15. 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.

  16. 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.

  17. Applicability of OSL pre-dose phenomenon of quartz in the estimation of equivalent dose

    Energy Technology Data Exchange (ETDEWEB)

    Koul, D.K., E-mail: dkkoul@barc.gov.i [Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Chougaonkar, M.P. [Environmental Assessment Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Polymeris, G.S. [Archaeometry Laboratory, Cultural and Educational Technology Institute, R.C. ' Athena' , Tsimiski 58, GR-67100, Xanthi (Greece)

    2010-01-15

    The feasibility of utilizing the pre-dosed OSL signal in the estimation of the equivalent dose has been investigated. The results based on (i) the behavior of growth curve, (ii) dose recovery tests and (iii) non-bleachability of reservoir centres, R-centres, suggests that (i) the pre-dosed OSL does not seem to work satisfactorily in dose estimation unlike the pre-dosed 110 deg. C TL emission and (ii) it may not be applicable in case of bleached specimen.

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

    DEFF Research Database (Denmark)

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

    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....

  19. Preparation of waterproof OSL dosimeters from hygroscopic materials with a special reference to NaCl:Cu

    Science.gov (United States)

    More, Y. K.; Wankhede, S. P.; Patil, R. R.; Kulkarni, M. S.; Kumar, Munish; Moharil, S. V.

    2016-05-01

    Optically stimulated luminescence (OSL) originally developed for geological/archaeological dating, has been found very useful for diverse applications in the field of radiation dosimetry. There is still a scarcity of OSL materials with demonstrated properties suited to dosimetry applications. Progress on the development of OSL materials with engineered properties has been slow and most research has focused on the OSL characterization of existing materials. One of the reasons for availability of only a handful of OSL dosimetry materials with adequate properties is that they have to satisfy certain stringent conditions necessary for such applications. Especially, hygroscopic materials are considered totally unsuitable. The efforts were made in our laboratory to overcome this problem. It is shown here that "water-proof" dosimeters can be prepared from even hygroscopic materials such as NaCl.

  20. Testing the potential of OSL, TT-OSL, IRSL and post-IR IRSL luminescence dating on a Middle Pleistocene sediment record of Lake El'gygytgyn, Russia

    Directory of Open Access Journals (Sweden)

    A. Zander

    2012-09-01

    Full Text Available Lake El'gygytgyn is a 12 km wide crater lake located in remote Chukotka in the far East Russian Arctic about 100 km to the north of the Arctic Circle. It was formed by a meteorite impact about 3.58 Ma ago. This study tests the paleomagnetic and proxy data-based Mid- to Late-Pleistocene sediment deposition history using novel luminescence dating techniques of 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. Polymineral sub-samples were analysed by infra-red stimulated luminescence (IRSL and post-IR infra-red stimulated luminescence (post-IR IRSL 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 TT-OSL approach. According to an independent age model, the lowest sample from 27.8–27.9 m below lake bottom level correlates to the Brunhes-Matuyama (B/M reversal. Finally, the SAR post-IR-IRSL protocol applied to polymineral fine grains was the only luminescence technique able to provide dating results of acceptable accuracy up to ca. 700 ka. Major factors limiting precision and accuracy of the luminescence chronology are, for some samples, natural signals already approaching saturation level, and overall the uncertainty related to the sediment water content and its variations over geological times.

  1. OSL age determinations of Pleistocene fluvial deposits in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Emílio A.A. Soares

    2010-09-01

    Full Text Available Absolute dating methods have been used in chronological studies of geological processes and sedimentary units of Quaternary age in Central Amazonia, Brazil. Although radiocarbon dating has been very useful in archaeological research and soil studies, the temporal interval of this method is inefficient in evaluating the sedimentation aspects and geological events from the beginning of the Quaternary in the Amazon basin. The use of crystal luminescence dating has been one of the most promising tool for determining the absolute dating of Quaternary deposits in the Amazonian region. Optically stimulated luminescence (OSL dating, following the MAR and SAR protocols, in a tectonic-sedimentary study of Quaternary fluvial deposits in the confluence area of the Negro and Solimões rivers, indicated ages from 1.3 (Holocene to about 67.4 kyears (Late Pleistocene for these sediments. Low radioactive isotope concentrations were found about 2ppm for 235U and 238U; 5ppm for 232Th; and the 40K concentrations were almost zero. A comparison was made between MAR and SAR protocols taking into account the fluvial depositional process.Métodos de datação absoluta têm sido usados em estudos cronológicos de processos geológicos e unidades sedimentares de idade quaternária na Amazônia Central, Brasil. Embora as datações pelo 14C tenham sido muito úteis na pesquisa arqueológica e estudos de solos, o intervalo de tempo abrangido por este método é ineficiente para avaliar aspectos da sedimentação e eventos geológicos do início do Quaternário na bacia Amazônica. O uso da datação por luminescência de cristais tem sido uma das ferramentas mais promissoras para a determinação da idade absoluta de depósitos quaternários na região amazônica. A datação por luminescência opticamente estimulada (LOE, seguindo os protocolos MAR e SAR, em um estudo tectono-sedimentar de depósitos aluviais quaternários da área de confluência dos rios Negro e Solim

  2. A portable multi-purpose OSL reader for UV dosimetry at workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, F. [Atomic Institute of the Austrian Universities, Vienna University of Technology, Stadionallee 2, AT-1020 Vienna (Austria); Hajek, M. [Atomic Institute of the Austrian Universities, Vienna University of Technology, Stadionallee 2, AT-1020 Vienna (Austria)], E-mail: mhajek@ati.ac.at; Bergmann, R. [Atomic Institute of the Austrian Universities, Vienna University of Technology, Stadionallee 2, AT-1020 Vienna (Austria); Brusl, H. [Austrian Social Insurance for Occupational Risks, Adalbert-Stifter-Strasse 65, AT-1200 Vienna (Austria); Fugger, M. [Atomic Institute of the Austrian Universities, Vienna University of Technology, Stadionallee 2, AT-1020 Vienna (Austria); Gratzl, W. [WEGS Data, Gatterholzgasse 14, AT-1120 Vienna (Austria); Kitz, E. [Austrian Social Insurance for Occupational Risks, Adalbert-Stifter-Strasse 65, AT-1200 Vienna (Austria); Vana, N. [Atomic Institute of the Austrian Universities, Vienna University of Technology, Stadionallee 2, AT-1020 Vienna (Austria)

    2008-02-15

    Optically stimulated luminescence (OSL) techniques are used for environmental radiation monitoring, luminescence dating and retrospective dosimetry. A portable and robust field instrument has been developed for the routine assessment of occupational exposure to ultraviolet (UV) radiation at workplaces. The design principles of hard- and software are described, along with preliminary measurements that illustrate the operation of the system and its capabilities.

  3. 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.

  4. 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...

  5. 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)

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Catherine C.O.; Alencar, Marcus A.V. de, E-mail: vallim@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    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)

  12. Testing portable luminescence reader signals against late Pleistocene to modern OSL ages of coastal and desert dunefield sand in Israel

    Science.gov (United States)

    Roskin, Joel; Sivan, Dorit; Bookman, Revital; Porat, Naomi; López, Gloria I.

    2017-04-01

    Rapid assessment of luminescence signals of poly-mineral samples by a pulsed-photon portable OSL reader (PPSL) is useful for interpreting sedimentary sections during fieldwork, and can assist with targeted field sampling for later full OSL dating and prioritize laboratory work. This study investigates PPSL signal intensities in order to assess its usefulness in obtaining relative OSL ages from linear regressions created by interpolating newly generated PPSL values of samples with existing OSL ages from two extensive Nilotic-sourced dunefields. Eighteen OSL-dated sand samples from two quartz-dominated sand systems in Israel were studied:(1) the Mediterranean littoral-sourced coastal dunefields that formed since the middle Holocene; and (2) the inland north-western Negev desert dunefield that rapidly formed between the Last Glacial Maximum and the Holocene. Samples from three coastal dune profiles were also measured. Results show that the PPSL signals differ by several orders of magnitude between modern and late Pleistocene sediments. The coastal and desert sand have different OSL age - PPSL signal ratios. Coastal sand show better correlations between PPSL values and OSL ages. However, using regression curves for each dunefield to interpolate ages is less useful than expected as samples with different ages exhibit similar PPSL signals. The coastal dune profiles yielded low luminescence signal values depicting a modern profile chronology. This study demonstrates that a rapid assessment of the relative OSL ages across different and extensive dunefields is useful and may be achieved. However, the OSL ages obtained by linear regression are only a very rough age estimate. The reasons for not obtaining more reliable ages need to be better understood, as several variables can affect the PPSL signal such as mineral provenance, intrinsic grain properties, micro-dosimetry and moisture content.

  13. OSL and TL techniques combined in a beryllium oxide detector to evaluate simultaneously accumulated and single doses.

    Science.gov (United States)

    Malthez, Anna L M C; Freitas, Marcelo B; Yoshimura, Elisabeth M; Umisedo, Nancy K; Button, Vera L S N

    2016-04-01

    Optically stimulated luminescence (OSL) and thermoluminescence (TL) are similar techniques widely used in radiation dosimetry. The main difference between these techniques is the stimulus to induce luminescence emission: TL technique uses thermal stimulation, whereas OSL uses optical stimulation. One of the main intrinsic characteristics of the OSL technique is the possibility of reading several times the dosimetric materials with a negligible loss of signal. In the case of BeO, recent studies have shown that TL stimulation up to 250°C does not affect its OSL signal. Taking the advantages of dosimetric characteristics of BeO combined with both techniques, in this study, we demonstrated the possibility of measuring accumulated and single doses in the same BeO-based detector in order to use it to improve individual monitoring of radiation workers exposed to X-ray or gamma-ray fields. Single doses were measured using TL technique by heating the detector up to 250°C, whereas accumulated doses were estimated using OSL technique in the same detector in a relatively short time of optical stimulation. The detectors were exposed to two energies: 28keV X-rays and 1.25MeV Co-60 gamma rays. The doses estimated by OSL and TL of BeO (Thermalox 995) were compared with those obtained with LiF (TLD-100) and recorded with a calibrated ionization chamber. The results indicate that combined OSL and TL signals of BeO detectors can provide additional information of accumulated dose, with additional exploration of the advantages of both techniques, such as speed in readouts with OSL, and double-check the doses using TL and OSL intensities from BeO.

  14. 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

    this stimulation source, and hi.-h-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......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\\feldspar mineral assemblages, or in separated quartz contaminated...

  15. Identification of defects responsible for optically stimulated luminescence (OSL) from copper-diffused LiAlO{sub 2} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Holston, M.S.; Ferguson, I.P.; Giles, N.C.; McClory, J.W. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, OH 45433 (United States); Halliburton, L.E., E-mail: Larry.Halliburton@mail.wvu.edu [Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506 (United States)

    2015-08-15

    A large optically stimulated luminescence (CW-OSL) response has been observed from bulk lithium aluminate (LiAlO{sub 2}) crystals that have been copper-diffused. After introducing the copper, an optical absorption band peaking at 277 nm is present and is assigned to Cu{sup +} (3d{sup 10}) ions at Li{sup +} sites. Photoluminescence (PL and PLE) from copper-diffused samples shows an emission band near 359 nm and an excitation band near 273 nm. These PL bands are also assigned to the Cu{sup +} ions. After an irradiation at room temperature with x-rays, the copper-diffused crystals give an intense OSL signal when stimulated with light in the 425–500 nm region. The OSL emitted light has a peak near 357 nm and thus is directly associated with recombination at a Cu ion. Electron paramagnetic resonance (EPR) shows that the x-rays produce two distinct Cu{sup 2+} (3d{sup 9}) centers, both at Li{sup +} sites. One of the trapped-hole centers is a Cu{sup 2+} with no nearby defects and the other is a Cu{sup 2+} with a neighboring Li{sup +} vacancy. Monitoring the EPR spectra before and after OSL shows that only the isolated Cu{sup 2+} ions (i.e., those with no nearby defect) participate in the OSL process. The electron traps participating in the OSL are shown with EPR to be transition-metal ions that are unintentionally present. Specifically, Fe{sup 2+} ions replacing Li{sup +} ions, possibly with a nearby lithium vacancy, convert to Fe{sup +} (3d{sup 7}) ions when they trap an electron during irradiation. These electrons are optically released by the OSL exciting light and migrate to the holes trapped as isolated Cu{sup 2+} ions, where electron–hole recombination gives the characteristic Cu{sup +} emission. By combining OSL, PL, and EPR, we establish the general OSL mechanism in copper-diffused LiAlO{sub 2} crystals. - Highlights: • Copper is diffused into LiAlO{sub 2} crystals at high temperature. • Cu{sup +} ions at Li{sup +} sites cause PL at 359 nm and PLE at 273 nm

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

    CERN Document Server

    Mrozik, Anna; Bilski, Pawel; Gieszczyk, Wojciech

    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 Al2O3, which is optically stimulated luminescence (OSL) material sensitive to ionizing radiation. This work is focused on determination of dose homogeneity within a 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 60Co and 137Cs 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 layer of copper-clad laminate and battery, in comparison to the dose at the front of the phone. The resistors showed the lower signal when the mobi...

  17. Retrospective dosimetry with EPR and OSL at McMaster University

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J.W.; Boreham, D.R.; Rink, W.J.; Mistry, R. [McMaster Univ., Ontario (Canada)

    2010-07-01

    Retrospective dosimetry may be of use following a radiological incident, in order to determine whether individuals may have been exposed. We briefly review the fundamentals of two primary techniques for retrospective biophysical dosimetry: electron paramagnetic resonance (EPR) and optically-stimulated luminescence (OSL). Our facility at McMaster University has the capability to perform both EPR and OSL dosimetry, which provides us with the flexibility to study so-called 'fortuitous' dosimeters with the most appropriate technique. In this paper, we review our research of the past decade, during which we have developed techniques for the measurement of absorbed dose in human, rodent, and canine dental enamel, synthetic quartz oscillators, and gypsum wallboard. (author)

  18. OSL and TSL interrelations in SrSO{sub 4}:Eu

    Energy Technology Data Exchange (ETDEWEB)

    Kerikmaee, M., E-mail: mihkel.kerikmae@ut.e [Faculty of Science and Technology, University of Tartu, Vanemuise 46, Tartu (Estonia); Danilkin, M.; Jaek, I.; Must, M.; Ots, A.; Pung, L.; Paernoja, E.; Ratas, A.; Seeman, V.; Tonutare, T. [Faculty of Science and Technology, University of Tartu, Vanemuise 46, Tartu (Estonia)

    2010-03-15

    Thermoluminescence (TL), dose-dependence of TL, optically stimulated luminescence (OSL), and EPR of Eu-doped strontium sulphate are studied. Eu enters the host lattice in 2+ charge state and does not change the charge state during energy storage and release. OSL disappears during pulse-step annealing of excited luminophor at the temperatures corresponding to dosimetric TL peak. Dosimetric TL peak can be destroyed by a continuous optical stimulation of excited sample. Ionizing radiation creates radiation defects in the host lattice, with the ionized sulphate anions being stable hole centres well above room temperature. Optical stimulation in the blue band (460-470 nm) causes the captured holes to be transported to the luminescence centres, similarly acts the heating of luminophor. The model of energy storage and release is discussed.

  19. 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.

  20. OSL dating of a Pleistocene maar: Birket Ram, the Golan heights

    Science.gov (United States)

    Shaanan, U.; Porat, N.; Navon, O.; Weinberger, R.; Calvert, A.; Weinstein, Y.

    2011-01-01

    Direct dating of maars and their phreatomagmatic deposits is difficult due to the dominance of lithic (host rock) fragments and glassy particles of the juvenile magma. In this paper we demonstrate that optically stimulated luminescence (OSL) dating can be successfully used for age determination of phreatomagmatic deposits. We studied the tuff deposit of Birket Ram, a basanitic maar located at the northern edge of the Golan heights on the western Arabian plate. The maar is underlain by a thick section of Pleistocene basalts, and currently hosts a small lake. It is filled by approximately 90m of lacustrine sediments with radiocarbon ages extrapolated to 108ka at the base. OSL was applied to quartz grains extracted from tuffs and paleosols in order to set the time frame of the phreatomagmatism at the site. A maximum age constraint of 179??13ka was determined for a paleosol that underlies the maar ejecta. Quartz grains from two layers in the tuff section yielded a direct age of 129??6ka for the phreatomagmatic eruption. A younger age of 104??7ka, which was determined for a tuff layer underlying a basaltic flow, was attributed to thermal resetting during the lava emplacement. This was confirmed by an 40Ar/39Ar age of 101??3ka determined on the overlying basalt. The internal consistency of the OSL ages and the agreement with the 40Ar/39Ar age determination as well as with previous estimates demonstrates the potential of OSL for maar dating. ?? 2010 Elsevier B.V.

  1. Review of optically stimulated luminescence (OSL) instrumental developments for retrospective dosimetry

    DEFF Research Database (Denmark)

    Bøtter-Jensen, Lars; Thomsen, Kristina Jørkov; Jain, Mayank

    2010-01-01

    This review describes 40 years of experience gained at Risø National Laboratory in the development of facilities for irradiation, thermal/optical stimulation and luminescence signal detection. These facilities have mainly been used in luminescence dating and nuclear accident dosimetry. We focus e...... especially on methods for light stimulation and irradiation, and developments of new portable TL/OSL readers for determining doses directly in the field on both Earth and the planet Mars....

  2. 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 examp......, at decadal to millennial timescales or perhaps longer (depending on the environmental dose rate) even for material subsequently buried. This has considerable potential in many archeological, geological and geo-hazard applications....

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

    Energy Technology Data Exchange (ETDEWEB)

    Afouxenidis, D.; Stefanaki, E.C.; Polymeris, G.S. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Physics Department, Aristotle University of Thessaloniki, University campus, Thessaloniki GR-54124 (Greece); Sakalis, A. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece); Tsirliganis, N.C. [Archaeometry Laboratory, Cultural and Educational Technology Institute/R.C. ' Athena' , Tsimiski 58, Xanthi 67100 (Greece)], E-mail: tnestor@ceti.gr; Kitis, G. [Physics Department, Aristotle University of Thessaloniki, University campus, Thessaloniki GR-54124 (Greece)

    2007-09-21

    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.

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

    Science.gov (United States)

    Sohbati, Reza; Murray, Andrew S.; Chapot, Melissa S.; Jain, Mayank; Pederson, Joel

    2012-09-01

    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 of Barrier Canyon Style (BCS) rock art in Canyonlands National Park, Utah, USA, is constrained. The natural OSL signal from quartz grains is measured from the surface to a depth of >10 mm in three different rock samples of the Jurassic Navajo Sandstone. Two samples are from talus with unknown daylight 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 ˜700 years before burial and that the unburied sample has been exposed for ˜120 years. The shielded surface of the buried talus sample is decorated with rock art; this rock fell from the adjacent Great Gallery panel. Related research using conventional OSL dating suggests that this rockfall event occurred ˜900 years ago, and so we deduce that the rock art must have been created between ˜1600 and 900 years ago. Our results are the first credible estimates of exposure ages based on luminescence bleaching profiles. The strength of this novel OSL method is its ability to establish both ongoing and prior exposure times, at decadal to millennial timescales or perhaps longer (depending on the environmental dose rate) even for material subsequently buried. This has considerable potential in many archeological, geological and geo

  5. Determination of average LET of therapeutic proton beams using Al2O3:C optically stimulated luminescence (OSL) detectors.

    Science.gov (United States)

    Sawakuchi, Gabriel O; Sahoo, Narayan; Gasparian, Patricia B R; Rodriguez, Matthew G; Archambault, Louis; Titt, Uwe; Yukihara, Eduardo G

    2010-09-07

    In this work we present a methodology and proof of concept to experimentally determine average linear energy transfer (LET) of therapeutic proton beams using the optically stimulated luminescence (OSL) of small Al(2)O(3):C detectors. Our methodology is based on the fact that the shape of the OSL decay curve of Al(2)O(3):C detectors depends on the LET of the radiation field. Thus, one can use the shape of the OSL decay curves to establish an LET calibration curve, which in turn permits measurements of LET. We performed irradiations at the M D Anderson Cancer Center Proton Therapy Center, Houston (PTCH), with passive scattering beams. We determined the average LET of the passive scattering beams using a validated Monte Carlo model of the PTCH passive scattering nozzle and correlated them with the shape of the OSL decay curve to obtain an LET calibration curve. Using this calibration curve and OSL measurements, we determined the averaged LET at various water-equivalent depths for therapeutic spread-out Bragg peaks and compared the results with averaged LETs determined using the Monte Carlo simulations. Agreement between measured and simulated fluence-averaged LET was within 24% for low energy spread-out Bragg peak (SOBP) fields and within 14% for high energy SOBP fields. Agreement between measured and simulated dose-averaged LET was within 12% for low energy SOBP fields and within 47% for high energy SOBP fields. The data presented in this work demonstrated the correlation between the OSL decay curve shapes and the average LET of the radiation fields, providing proof of concept of the feasibility of using OSL from Al(2)O(3):C detectors to measure average LET of therapeutic proton beams.

  6. 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.

  7. Investigation on heat sterilization of BeO-detectors for optical stimulated luminescence (OSL); Untersuchungen zur Hitzesterilisation von BeO-Detektoren fuer die optisch stimulierte Lumineszenz (OSL)

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, W.; Piehler, S.; Burgkhardt, B. [Duale Hochschule Baden-Wuerttemberg (DHBW), Karlsruhe (Germany). Sicherheitswesen

    2015-07-01

    BeO-Detectors show a high thermal stability when optically stimulated luminescence is measured. With respect to steam sterilization of extremity dosimeters in medicine this paper investigates the effect of heat treatments on the response at commonly used temperatures of 121 C and 134 C. A commercial OSL-dosimetry system with BeO detectors uses dosimeter trays made of none-heat resistant plastic. The detectors are welded with the tray. Constructing a tray which allowed the detectors to be taken out was essential to perform heat treatments in heat resistant holders. Up to 20 simulated heat treatments at 121 C as well as irradiations of one dosimeter during one month resulted in small changes of the detector response, within ±10%. Similar results were shown by one irradiation and one summed up heat treatment at 121 C and 134 C. This is also true for the characteristics of the response vs. time of the heat treatment.

  8. 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

  9. Geochronological (OSL) and geomorphological investigations at the presumed Frankfurt ice marginal position in northeast Germany

    Science.gov (United States)

    Hardt, Jacob; Lüthgens, Christopher; Hebenstreit, Robert; Böse, Margot

    2016-12-01

    The Weichselian Frankfurt ice marginal position in northeast Germany has been critically discussed in the past owing to weak morphological evidence and a lack of clear sedimentological records. This study aims to contribute to this discussion with new geochronological and geomorphological results. Apart from very few cosmogenic exposure ages, the time frame is to date still based on long distance correlation with radiocarbon chronologies. We selected a study site in a key position regarding the classic location of the Frankfurt ice marginal position and the recently described arcuate ridge structures on the Barnim plateau. For the first time we present Optically Stimulated Luminescence (OSL) ages of quartz from glaciofluvial deposits for this Weichselian phase. Our results indicate an advance of the Scandinavian Ice Sheet (SIS) at around 34.1 ± 4.6 ka. This is in agreement with OSL ages from sandur deposits at the Brandenburg ice marginal position located farther south and could also be correlated with the Klintholm advance in Denmark. The subsequent meltdown phase lasted until around 26.3 ± 3.7 ka. During the meltdown phase a minor oscillation of the SIS caused the formation of the recently described arcuate ridges on the Barnim till plain. Recalculated surface exposure ages of glacigenic boulders with an updated global production rate indicate a landscape stabilization phase at around 22.7 ± 1.6 ka, which is in agreement with our ages. A phase of strong aeolian activity has been dated with OSL to 1 ± 0.1 ka; this may have been triggered by human activities that are documented in this region for the medieval period.

  10. CW-OSL measurement protocols using optical fibre Al2O3:C dosemeters

    DEFF Research Database (Denmark)

    Edmund, J.M.; Andersen, C.E.; Marckmann, C.J.

    2006-01-01

    A new system for in vivo dosimetry during radiotherapy has been introduced. Luminescence signals from a small crystal of carbon-doped aluminium oxide (Al2O3:C) are transmitted through an optical fibre cable to an instrument that contains optical filters, a photomultiplier tube and a green (532 nm......) laser. The prime output is continuous wave optically stimulated luminescence (CW-OSL) used for the measurement of the integrated dose. We demonstrate a measurement protocol with high reproducibility and improved linearity, which is suitable for clinical dosimetry. A crystal-specific minimum pre...

  11. 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.

  12. 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

    Luminescence dating is one of the most promising technique available for studying bioturbation on pedological timescales. In this study, we use multi-grain and single-grain quartz OSL to quantify termite bioturbation processes (Macrotermes natalensis) in a savannah ecosystem in Ghana. Termites...... is effectively bleached during the erosion process allowing us to quantify retrospectively, for the first time, the surface deposition rate, the inverse of the upwards transport rate. At this site, this is ~0.28 mm year-1 and began about 4.000 years ago. Downward mixing through subsurface galleries may replace...

  13. Optically stimulated luminescence (OSL) of Lu{sub 2}SiO{sub 5}:Ce powder: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Gartia, R.K., E-mail: rkgartia02@yahoo.i [Physics Department, Manipur University, Imphal 795003 (India); Singh, Th. Tejkumar [Physics Department, Manipur University, Imphal 795003 (India); Singh, Th. Basanta [Luminescence Dating Laboratory, Manipur University, Imphal 795003 (India)

    2011-01-01

    Optically stimulated luminescence (OSL) of Lu{sub 2}SiO{sub 5}:Ce powder (Phosphor Technology Ltd., UK) has been measured by Riso TL/OSL Reader (TL-DA-15). Upon blue photon stimulation ({lambda}{sub ex} {approx}470 nm) the material shows strong OSL signal that can detect {beta}-irradiation right up to the dose of {approx}0.2 Gy. A brief discussion on this finding is presented by comparing the thermoluminescence of the system with and without optical stimulation. The two key important parameters namely, trap-depth (E) and frequency factor (s) of the main peaks that occur at 85 and 232 {sup o}C are determined.

  14. 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

    Optically stimulated luminescence (OSL) signals from feldspar and quartz samples were studied using infrared (860 nm) and green light (420-575 nm) stimulation. A serious problem connected with the regeneration technique used for dating is associated with a change of OSL sensitivity to radiation...... in the couse of the measurement process. A typical effect seen is a large increase of the apparent strength of our beta source when calibrated against a gamma source. If the regeneration procedure is used, it is shown that the sensitivity increases up to similar to 50% during the measurement process...... 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...

  15. TL/OSL properties of beta irradiated Al2O3 Nanophosphor synthesized by microwave combustion method

    Science.gov (United States)

    Reddy, S. Satyanarayana; Nagabhushana, K. R.; Chauhan, Naveen; Singh, Fouran

    2017-05-01

    Stable α-phase of Al2O3 is synthesized by combustion method usingtemperature controlled microwave oven. Crystalline phase is analyzed by X-ray diffraction (XRD)and average crystallite size is found to be 75 nm. Thermoluminescence (TL) glow curve of Al2O3 is studied in UV, blue and open (visible) windows after beta irradiation. A prominent TL glow with peak at 472 K along with shoulders at 416 and 513 K are observed in all three windows. These peaks may be ascribed to F, F2 and F+- centers. Highest TL intensity isobserved inopen window. Optically stimulated luminescence (OSL) studies in UV and blue windows shows highest intensityin UV window. TL/OSL of phosphor shows linearresponse with beta dose upto 6.16 Gy.TL/OSL properties viz fading,repeatabilityand MDDare studied. TL kinetic parameters are estimated by deconvolution with computerized glow curve deconvolution (CGCD) techniques.

  16. Optimização da metodologia de avaliação de doses de corpo inteiro em dosimetria individual de radiação externa

    OpenAIRE

    Batel, Vera Inês Pimentel

    2009-01-01

    Tese de mestrado, Engenharia Física, Universidade de Lisboa, Faculdade de Ciências, 2009 Este trabalho foi realizado no Serviço de Dosimetria Individual (SDI) do Instituto Tecnológico e Nuclear (ITN), na Unidade de Protecção e Segurança Radiológica (UPSR). Caracterizou-se o dosímetro individual de corpo inteiro termo luminescente, cujo detector é deLiF:Mg,Ti (TLD-100) e a leitura dos mesmo realizada nos leitores semi-automáticos Harshaw6600. O conjunto dosímetro e leitor de dosímetros cons...

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

    DEFF Research Database (Denmark)

    Gaza, R.; McKeever, S.W.S.; Akselrod, M.S.

    2004-01-01

    We describe a high-sensitivity, fiber-optic dosimetry system based on optically stimulated luminescence (OSL) and radioluminescence from Al2O3: 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 f...

  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. Soil development in OSL dated sandy dune substrates under Quercus robur Forest (Netherlands)

    Science.gov (United States)

    van Mourik, J. M.; Nierop, Ir. K.; Verstraten, J. M.

    2009-04-01

    Coastal dune landscapes are very dynamic. The present distribution of vegetation and soil is the result of over 2000 years of natural processes and human management. The initial soil development was controlled by an increase of the organic matter content, which consisted mainly of decomposed roots of grasses (rhizomull), and a decrease of the soil pH to 3-4 by decalcification. This stage was followed by the development of a deciduous forest, which was dominated by Quercus robur. Since 1600 AD, a large part of the deciduous forest that dominated the east side of the coastal dune landscape transferred in expensive residential areas and urbanizations. Nevertheless some parts of the oak forest belt remained. The present forest soils are acid and the controlling soil processes are leaching of sesquioxides and storage of organic matter in mormoder humus forms. The sustainability of ecosystems is closely related to the quality of the humus form, controlling nutrient cycling and water supply. Therefore, improve of knowledge of humus form development and properties is important. We applied soil micromorphology and pyrolysis-gas chromatography/mass spectrometry (GC/MS) to investigate more details of humus form development at two locations (Duivendrift and Hoek van Klaas) in the coastal dune area of the Amsterdamse Waterleidingduinen (near Haarlem, the Netherlands). However, to understand forest soil development, including the organic matter composition in the humus form, the age of the substrate and the forest is required. Therefore, we used tradition techniques as pollen analysis and radiocarbon dating but also the recently introduced optical stimulated luminescence (OSL) dating technique. OSL dating works excellent for aeolian sandy deposits with a high percentage of quartz grains. The OSL age is defined as the time after the last bleaching by solar radiation of mineral grains. Or in other words, the start of a stable period without sand drifting. In the Ah horizons we

  20. Fundamental investigations of natural and laboratory generated SAR dose response curves for quartz OSL in the high dose range

    DEFF Research Database (Denmark)

    Timar-Gabor, Alida; Constantin, Daniela; Buylaert, Jan-Pieter;

    2015-01-01

    SAR-OSL investigations on quartz from Romanian loess resulted in non concordant fine and coarse-grain ages for equivalent doses higher than ~100 Gy. The laboratory dose response for both grain sizes is well represented by a sum of two saturating exponential functions, fine and coarse grains chara...

  1. 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

    Pulsed stimulation has earlier been proven useful for several applications in dosimetry and luminescence research. Pulsed stimulation has been integrated in the Risø TL/OSL reader along with a software control built into the Sequence Editor. To facilitate research of the lifetime or delay involved...

  2. 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

    Multiple-aliquot quartz OSL dose-response curves often suffer from substantial variability in the luminescence output from identically treated aliquots (scatter) that leads to large uncertainties in the equivalent-dose estimates. In this study, normalisation and its bearing on the accuracy...

  3. 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

  4. 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.

  5. 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

  6. A compact design for monochromatic OSL measurements in the wavelength range 380-1020 nm

    Energy Technology Data Exchange (ETDEWEB)

    Boetter-Jensen, L.; Poolton, N.R.J.; Willumsen, F.; Christiansen, H. [Risoe National Lab., Roskilde (Denmark)

    1994-04-01

    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 automated Risoe 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 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 are demonstrated in the article. (author).

  7. OSL dating results of post-Barreiras sediments in the Paraiba basin, Northeastern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Tudela, Diego R.G.; Munita, Casimiro S., E-mail: drtudela@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Mittani, Juan C.R.; Tatumi, Sonia H., E-mail: tatumi@fatecsp.br [Faculdade de Tecnologia de Sao Paulo (FATEC-SP/CEETEPS), Laboratorio de Datacao e Luminescencia de Cristais, Sao Paulo, SP (Brazil); Rossetti, Dilce F., E-mail: rossetti@dsr.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Centro de Observacao da Terra, Divisao de Sensoriamento Remoto - DSR

    2011-07-01

    In the present study we show ages of 39 sediments samples of two sedimentary units (PB1 and PB2) collected from Paraiba Basin, northeastern Brazil, obtained by optically stimulated luminescence (OSL) making use of standardized growth curve (SGC) and applying single aliquot regenerative dose (SAR) protocol in 15 randomly selected samples to validate the equivalent Dose (D{sub e}). Environmental radiation dosimetry of the area was performed to evaluate the natural concentrations of {sup 238}U, {sup 232}Th and {sup 40}K and in this way annual dose rates of the locations were evaluated. The results showed natural radioisotopes concentrations between 0.542-4.879 ppm for U, 1.314-26.098 ppm for Th and 0.141-1.12% for K and annual dose rates between 439-4172{mu}Gy/yr. The ages ranged from 1.8-178.3 kyr were obtained, and they are in agreements with the geological considerations. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Jain, M. [Risoe National Laboratory, DK-4000 Roskilde (Denmark) and Institute of Geography and Earth Sciences, University of Wales, Aberystwyth, Wales SY23 3DB (United Kingdom)]. E-mail: mgj@aber.ac.uk; Murray, A.S. [Nordic Laboratory for Luminescence Dating, Department of Earth Sciences, Aarhus University, Risoe National Laboratory, DK-4000 Roskilde (Denmark); Boetter-Jensen, L. [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Wintle, A.G. [Institute of Geography and Earth Sciences, University of Wales, Aberystwyth, Wales SY23 3DB (United Kingdom)

    2005-06-01

    In the optically stimulated luminescence (OSL) dating of quartz, the presence of significant medium and slow components in the initial-OSL signal (first 0.8s 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 the fast component alone. In this paper, the reduction of fast component OSL by high temperature infrared (IR) stimulation is investigated. It is shown that, in the temperature range from 120-190-bar C, it is possible to deplete the fast component preferentially using IR stimulation. The thermal assistance energy required for IR stimulation (1.49eV; 830nm) of the fast component is calculated to be 0.41+/-0.02eV. However, the elevated temperature IRSL of quartz has a poor signal-to-noise ratio; hence a single-aliquot regenerative-dose (SAR) protocol based on a differential-OSL signal (the difference between the two short OSL signals separated by an elevated temperature IR stimulation) is proposed. The measurement conditions are optimised following examination of both the photoionisation cross-sections of the fast component for different stimulation temperatures, and possible thermally induced sensitivity changes arising from holding the samples at high temperatures for long periods ({approx}1500s). The resulting equivalent dose values, and those from a conventional SAR protocol based on the initial-OSL signal, are compared with the expected doses for several samples. We observe that for samples with relatively strong medium and slow components, the SAR protocol based on isolation of the fast component (derived by IR depletion of the OSL) gives significantly more accurate estimates than the SAR protocol using net initial OSL signals. On the other hand, accurate dose estimates are obtained from samples dominated by the fast component using both protocols. Finally, the implications are discussed for dosimetry using quartz.

  9. OSL surface exposure dating of wave-emplaced coastal boulders - Research concept and first results from the Rabat coast, Morocco

    Science.gov (United States)

    Brill, Dominik; May, Simon Matthias; Mhammdi, Nadia; King, Georgina; Brückner, Helmut

    2017-04-01

    Fields of wave-emplaced blocks and boulders represent impressive evidence of cyclone and tsunami flooding over Holocene time scales. Unfortunately, their use for coastal hazard assessment is in many cases impeded by the absence of appropriate dating approaches, which are needed to generate robust chronologies. The commonly applied AMS-14C, U/Th or ESR dating of coral-reef rocks and marine organisms attached to the clasts depends on a - mostly hypothetical - coincidence between the organisms' death and boulder displacement, and inferred event chronologies may be biased by the marine 14C-reservoir effect and reworked organisms. Here we discuss the potential of the recently developed optically stimulated luminescence (OSL) surface exposure dating technique to directly date the relocation process of wave-emplaced boulders. By measuring the depth-dependent resetting of luminescence signals in exposed rock surfaces and comparing it to the signal-depth profiles of known-age samples, OSL surface exposure dating may be capable to model direct depositional ages for boulder transport. Thereby, it promises to overcome the limitations of existing dating techniques, and to decipher complex transport histories of clasts that underwent multiple phases of exposure and burial. The concept and some first results of OSL surface exposure dating shall be presented for coastal boulders from the Rabat coast, Morocco, where the preconditions for successful dating are promising: (i) Several coastal boulders show clear indication of overturning during wave transport in the form of downward-facing bio-eroded surfaces; (ii) the boulders are composed of different types of sandstone that contain quartz and feldspar, the required dosimeters for OSL dating; (iii) all boulders are of Holocene age and, therefore, in the dating range of OSL surface exposure dating. The main challenges for a successful application are the intensive bio-erosion and weathering of some surfaces exposed after transport

  10. 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.

  11. Comparing OSL and CN techniques for dating fluvial terraces and estimating surface process rates in Pamir

    Science.gov (United States)

    Fuchs, Margret; Gloaguen, Richard; Pohl, Eric; Sulaymonova, Vasila; Merchel, Silke; Rugel, Georg

    2014-05-01

    The quantification of surface process rates is crucial for understanding the topographic evolution of high mountains. Spatial and temporal variations in fluvial incision and basin-wide erosion enable to decipher the role of tectonic and climatic drivers. The Pamir is peculiar in both aspects because of its location at the western end of the India-Asia collision zone, and its position at the edge of two atmospheric circulation systems, the Westerlies and the Indian Summer Monsoon. The architecture of the Panj river network indicates prominent variations across the main tectonic structures of the Pamir. The trunk stream, deflects from the predominantly westward river orientation and cuts across the southern and central Pamir domes before doubling back to the west and leaving the orogen. Optically stimulated luminescence (OSL) dating of fluvial terraces reveals short-term sedimentation along the trunk stream during the last ~25 kyr. The agreement of OSL results to new exposure ages based on the cosmogenic nuclide (CN) 10Be confirms accurate terrace age modelling and treatment of incomplete bleaching. The consistent terrace sedimentation and exposure ages suggest also fast terrace abandonment and rapid onset of incision. Considerable differences in terrace heights reflect high spatial variations of fluvial incision, independent of time interval, change in rock type or catchment increase. Highest rates of (5.9 ± 1.1) mm/yr to (10.0 ± 2.0) mm/yr describe the fluvial dynamic across the Shakhdara Dome and that related to the Darvaz Fault Zone. Lower rates of (3.9 ± 0.6) mm/yr to (4.5 ± 0.7) mm/yr indicate a transient stage north of the Yazgulom Dome. Fluvial incision decreases to rates ranging from (1.7 ± 0.3) mm/yr to (3.9 ± 0.7) mm/yr in graded river reaches associated to southern dome boundaries. The pattern agrees to the interpretation of successive upstream river captures across the southern and central Pamir domes inferred from morphometric analyses of river

  12. 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...... luminescence characteristics. The variation in the natural OSL signal with depth below the cobble surface using intact slices from two different cobbles shows that both were bleached to a depth of at least similar to 2?mm before deposition. A model of the variation of dose with depth fitted to data from one...... contained within a single clast, and this suggests that the luminescence dating of rock surfaces may prove, in the future, to be at least as important as sand/silt sediment dating....

  13. 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...... in theTabernas Basin, SE Spain. A total of 23 samples was collected from the fluvial terraces for dating usingquartz OSL. Sixteen of the samples could not be dated because of low saturation levels (e.g. typical2xD0 ... usingboth multi-grain and single-grain analysis. Single grain results show that: (i) measurements from multigrainaliquots overestimate ages by up to ~ 4 ka for modern analogues and young samples (

  14. 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)

  15. 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...... in theTabernas Basin, SE Spain. A total of 23 samples was collected from the fluvial terraces for dating usingquartz OSL. Sixteen of the samples could not be dated because of low saturation levels (e.g. typical2xD0 ... usingboth multi-grain and single-grain analysis. Single grain results show that: (i) measurements from multigrainaliquots overestimate ages by up to ~ 4 ka for modern analogues and young samples (

  16. Controle de qualidade e dosimetria em equipamentos de tomografia computadorizada Quality control and dosimetry in computed tomography units

    Directory of Open Access Journals (Sweden)

    Diana Rodrigues de Pina

    2009-06-01

    Full Text Available OBJETIVO: Avaliação de condições dos equipamentos e dosimetria em setores de tomografia computadorizada utilizando protocolos de cabeça, abdome e coluna lombar em pacientes adultos (em três equipamentos distintos e pediátricos com até um ano e meio de vida (em um dos equipamentos avaliados. MATERIAIS E MÉTODOS: Foram estimados o índice de dose em tomografia computadorizada e a dose média em cortes múltiplos, em exames com pacientes adultos, em três distintos equipamentos. Ainda foram estimadas as doses na superfície de entrada e as doses absorvidas em exame de cabeça para pacientes adultos e pediátricos em um dos equipamentos avaliados. RESULTADOS: Foram realizados testes de controle de qualidade, mecânicos, demonstrando que os equipamentos satisfazem as especificações de uso estabelecidas pelas normas vigentes. Os resultados da dosimetria mostraram que valores de dose média em cortes múltiplos excederam em até 109,0% os valores de níveis de referência, apresentando consideráveis variações entre os equipamentos avaliados neste estudo. As doses absorvidas obtidas com protocolos pediátricos são inferiores aos de pacientes adultos, apresentando redução de até 51,0% na tireoide. CONCLUSÃO: Neste estudo foram avaliadas as condições de operação de três equipamentos tomográficos, estabelecendo quais parâmetros devem ser trabalhados para a implantação de um programa de controle de qualidade nas instituições onde esta pesquisa foi desenvolvida.OBJECTIVE: Evaluation of equipment conditions and dosimetry in computed tomography services utilizing protocols for head, abdomen, and lumbar spine in adult patients (in three different units and pediatric patients up to 18 months of age (in one of the units evaluated. MATERIALS AND METHODS: Computed tomography dose index and multiple-scan average dose were estimated in studies of adult patients with three different units. Additionally, entrance surface doses as well as

  17. Paleoenvironmental change in central Chile as inferred from OSL dating of ancient coastal sand dunes

    Science.gov (United States)

    Andrade, Belisario; Garcia, Juan L.; Lüthgens, Christopher; Fiebig, Markus

    2013-04-01

    To present day, the climatic and geographic expression of glacials and interglacials in the semiarid coast of central Chile remains unclear. The lack of well dated paleoclimatic records has up to now precluded firm conclusions whether maximum glacials evident in the Andes mountain range probably coincide with wetter (e.g., pluvials) or drier conditions at the coast. The natural region locally known as "Norte Chico" represents a transitional semiarid area between the extreme Atacama Desert to the North and the wetter, Mediterranean-like type of climate, to the South. In this semiarid region of Chile several generations of eolian sand dunes, some of them separated by paleosoils, have been preserved. In addition to the occurrence of paleosoils, thick debris flow deposits in some places overly ancient dune bodies, likely indicating significant environmental changes during the formation of these archives. However, the exact timing of these processes within the mid to late Pleistocene and Holocene is still unclear. A key aspect is that some of the ancient dunes are recently hanging above rocky coastlines, where no supply of sand exists today, likely implying their formation during a lower than present, probably glacio-eustatically induced sea level. The location of the research area in a key mid-latitude region of the eastern Pacific in combination with the preserved landform record offers a chance to reconstruct climatic shifts during the Quaternary by studying the variability of morphogenetic conditions throughout time, in order to promote knowledge about possible forcing factors driving climatic variability. Within this pilot study, samples for optically stimulated luminescence (OSL) dating were taken from three different stratigraphic sections that denote a complex environmental variability as indicated by paleosoils and debris flow units intercalated in ancient sand dunes. First dating results inferred from OSL measurements using a post-IR IRSL (pIRIR) protocol for

  18. Combining bulk sediment OSL and meteoric 10 Be fingerprinting techniques to identify gully initiation sites and erosion depths

    OpenAIRE

    Portenga, E.W.; Bishop, P; Rood, D.H.; Bierman, P.R.

    2017-01-01

    Deep erosional gullies dissect landscapes around the world. Existing erosion models focus on predicting where gullies might begin to erode, but identifying where existing gullies were initiated and under what conditions is difficult, especially when historical records are unavailable. Here we outline a new approach for fingerprinting alluvium and tracing it back to its source by combining bulk sediment optically stimulated luminescence (bulk OSL) and meteoric 10Be (10Bem) measurements made on...

  19. A comparison of OSL ages derived from silt-sized quartz and polymineral grains from Chinese loess

    Science.gov (United States)

    Watanuki, T.; Murray, A. S.; Tsukamoto, S.

    2003-05-01

    Recent work (Watanuki et al., submitted) has shown by comparison with independent age control that silt-sized quartz grains extracted from Japanese loess can be used for optically stimulated luminescence (OSL) dating for equivalent doses of up to 425 Gy (˜500 ka at these sites). Further comparison with infrared (IR) stimulated and post-IR blue-stimulated OSL showed that the latter signal gave accurate ages, and was probably dominated by quartz, whereas the former systematically underestimated ages in the range 30-600 ka, and showed fading in laboratory tests. The main source of the loess deposits in Japan is the Chinese mainland; in eastern Asia, loess is widely distributed by the prevailing westerly winds, and one of the main sources is in the western desert areas of China. Unfortunately, independent age control is very unusual in loess deposits in China, and there is little evidence for the accuracy of existing luminescence ages from this material. As an alternative approach, this study builds on the Japanese results by using loess from two Chinese sites, and examining the relationship between single-aliquot regeneration dose IR and post-IR blue-stimulated luminescence ages from polymineral samples, and blue-stimulated quartz luminescence ages. The normalized blue-stimulated OSL intensity from quartz from the eastern site was about 10 times that from the west, suggesting either a different source of material, or (less likely) an increase in quartz sensitivity with transport distance. By comparison with quartz results we conclude that, in our samples of Chinese loess, the post-IR blue-stimulated OSL is the more reliable polymineral signal, when compared with the IR signal. It may nevertheless include a feldspar component, and this should be tested for using laboratory fading experiments.

  20. Fundamental investigations of natural and laboratory generated SAR dose response curves for quartz OSL in the high dose range

    DEFF Research Database (Denmark)

    Timar-Gabor, Alida; Constantin, Daniela; Buylaert, Jan-Pieter

    2015-01-01

    SAR-OSL investigations on quartz from Romanian loess resulted in non concordant fine and coarse-grain ages for equivalent doses higher than ~100 Gy. The laboratory dose response for both grain sizes is well represented by a sum of two saturating exponential functions, fine and coarse grains chara...... equivalent dose of 2000e2500 Gy were found to be below the saturation level of the laboratory dose response curve for both grain sizes; this also applied to the luminescence signals measured after >5000 Gy given on top of natural doses. © 2015 Elsevier Ltd. All rights reserved....... characterised by D01 and D02 values of ~140 and ~1400 Gy and ~65 and ~650 Gy respectively. Pulsed OSL experiments confirmed that this behaviour is almost certainly inherent to quartz and not caused by contamination with another mineral. Natural doseeresponse curves do not follow the same pattern and enter...... saturation much earlier. Analysis of time resolved spectra indicated similar luminescence lifetimes for both fine and coarse quartz grains, and natural and laboratory generated OSL signals seem to use the same non-dosedependent recombination pathways. The natural signals of a sample with an expected...

  1. 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

    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...... test whether: (1) Yangtze subaqueous delta sediments contain quartz with suitable characteristics for dating, and (2) quartz grains are well-bleached during/before the transportation process, by examining a modern analogue of suspended particulate matter, and by cross-checking with the doses derived...... from infrared stimulated luminescence (IRSL) signals (both IR50 and pIRIR160) from feldspar in polymineral fine grains. We find that both the quartz and feldspar luminescence characteristics are satisfactory (quartz dose recovery ratio 1.067 ± 0.004; n = 250, pIRIR160 dose recovery ratio 1.01 ± 0.02; n...

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

    Energy Technology Data Exchange (ETDEWEB)

    Veronese, Ivan, E-mail: ivan.veronese@unimi.i [Dipartimento di Fisica, Universita degli Studi di Milano and INFN Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Galli, Anna [CNR-INFM, via Cozzi 53, 20125 Milano (Italy); Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca and INFN Sezione di Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Cantone, Marie Claire [Dipartimento di Fisica, Universita degli Studi di Milano and INFN Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Martini, Marco [Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca and INFN Sezione di Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Vernizzi, Fabrizio; Guzzi, Gianpaolo [Italian Association for Metals and Biocompatibility Research - A.I.R.M.E.B., Milan (Italy)

    2010-01-15

    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.

  3. 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)

  4. Stability of fine-grained TT-OSL and post-IR IRSL signals from a i>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 the X...

  5. Study of thermoluminescence (TL) and optically stimulated luminescence (OSL) from α-keratin protein found in human hairs and nails: potential use in radiation dosimetry.

    Science.gov (United States)

    Mishra, D R; Soni, A; Rawat, N S; Bokam, G

    2016-05-01

    The thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of human nails and hairs containing α-keratin proteins have been investigated. For the present studies, black hairs and finger nails were selectively collected from individuals with ages between 25 and 35 years. The collected hairs/nails were cut to a size of TL glow peaks in the temperature range from 70 to 210 ° C. Continuous wave (CW)-OSL measurements of hair samples at a wavelength of 470 nm showed the presence of two distinct OSL components with photoionization cross section (PIC) values of about 1.65 × 10(-18) cm(2) and about 3.48 × 10(-19) cm(2), while measurements of nail samples showed PIC values of about 6.98 × 10(-18) cm(2) and about 8.7 × 10(-19) cm(2), respectively. This difference in PIC values for hair and nail samples from the same individual is attributed to different arrangement of α-keratin protein concentrations in the samples. The OSL sensitivity was found to vary ± 5 times among nail and hair samples from different individuals, with significant fading (60% in 11 h) at room temperature. The remaining signal (after fading) can be useful for dose estimation when a highly sensitive OSL reader is used. In the absorbed dose range of 100 mGy-100 Gy, both the TL and OSL signals of hair and nail samples showed linear dose dependence. The results obtained in the present study suggest that OSL using hair and nail samples may provide a supplementary method of dose estimation in radiological and nuclear emergencies.

  6. OSL and photo-transferred TL of quartz single crystals sensitized by high-dose of gamma-radiation and moderate heat-treatments.

    Science.gov (United States)

    Ferreira de Souza, Leonardo B; Guzzo, Pedro L; Khoury, Helen J

    2014-12-01

    This study investigates the optically stimulated luminescence (OSL) and the photo-transferred thermoluminescence (PTTL) signals in quartz single crystals showing a strong TL peak near 300°C after being sensitized by irradiation with 25kGy of gamma rays and heating at 400°C. Natural and sensitized samples were prepared from two crystals with different sensitivity levels in the 300°C TL region. Continuous-wave (CW) and linearly-modulated (LM) OSL signals were stimulated with blue light-emitting diodes during 40 and 1000s, respectively. Two components were isolated from the CW-OSL signals of sensitized samples. These components were clearly seen in LM-OSL measurements together with two long-term components. LM-OSL showed that the sensitization process considered in this study sensitized an ultrafast OSL component of these crystals. The similar behavior found for the thermal stabilities of OSL and TL signals and the dependence of these signals with sample origins suggested that the trapping site related to the ultrafast component is also related to the TL process of the sensitized peak. The PTTL signal induced by blue LEDs increased the intensity of the sensitized glow peak. On the other hand, a remarkable reduction in the intensity of this peak as a result of the accumulated effect of blue light exposure was clearly seen in both kinds of crystals. These results were explained by a mechanism of competition between optically unstable deep traps and trap levels responsible to the sensitized TL peak. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Quantification of glacial erosion in the Alps using OSL-thermochronology

    Science.gov (United States)

    Herman, F.; Champagnac, J.-D.; Rhodes, E. J.; Jaiswal, M.; Chen, Y.-G.; Schwenninger, J.-L.

    2009-04-01

    The impact of glaciations on the topography of the Alps is still unclear: Long-term denudation rate determined by low-T thermochronology are in the range of 0.2 to 1 mm/yr, and increased during the Plio-Quaternary by ~3 fold (Vernon et al., 2008). Such an increase is also documented by peri-alpine sediment budget (Kuhleman, 2000), with a two to three fold increase in sediment yields since 5-3 Ma. This increase was considered as evidence of a climatically-driven surface process change, a large component of which was attributed to increased precipitation (Cederbom et al., 2004) and erosion by glacial processes (Champagnac et al., 2007). The transition from full fluvial to glaciated landscape must have involved major changes in topography and erosion rates, in particular given the changes in sediment yield (Kuhlemann, 2000; Mutoni et al 2003). However, the timing of the onset of intense glacial erosion as well as its rates are still ambiguous. The glacial erosion seems to have accelerated around 0.9 Ma as suggested by the ten fold increase of incision rates of a valley in the Central Alps (Häuselmann et al., 2007), and by information about vegetation and sedimentologic changes (Muttoni et al., 2003; Scardia et al., 2006). There is however no direct quantification of topographic change during the Plio-Quaternary. We present here how we use OSL-thermochronology, a new thermochronometer of exceptionally low closure temperature (about 30-400 C) (Herman et al subm.) and a glacial erosion model (Herman and Braun 2008) to estimate topographic changes in the Alps in response to glaciations. Because of its low closure temperature, OSL-thermochronology enables quantification of events of less than 1 Ma at very small wavelength of the topography. We collected two vertical profiles, one in the Zermatt Valley (Valais) and one in Maurienne Valley (Savoy). We infer from these results changes in topography, date and quantify relief creation under glacial - interglacial cycles

  8. QUANTIFICATION OF GLACIAL EROSION IN THE ALPS USING VERY LOW-TEMPERATURE THERMOCHRONOLOGY (OSL & AHe)

    Science.gov (United States)

    Champagnac, J.; Herman, F.; Rhodes, E. J.; Fellin, M.; Jaiswal, M.; Schwenninger, J.; Reverman, R. L.

    2009-12-01

    The impact of glaciations on the topography of the Alps is still unclear: Long-term denudation rate determined by low-T thermochronology are in the range of 0.2 to 1 mm/yr, and increased during the Plio-Quaternary by 3 fold (Vernon et al., 2008). Such an increase is also documented by peri-alpine sediment budget (Kuhleman, 2000), with a similar increase in sediment yields since 5-3 Ma. This increase was considered as evidence of a climatically-driven surface process change, attributed to increased precipitation (Cederbom et al., 2004) and erosion by glacial processes (Champagnac et al., 2007). The timing of the onset of intense glacial erosion as well as its rates are still ambiguous. The glacial erosion seems to have accelerated around 0.9 Ma as suggested by the ten fold increase of incision rates of a valley in the Central Alps (Häuselmann et al., 2007), and by information about vegetation and sedimentologic changes (Muttoni et al., 2003). There is however no direct quantification of topographic change during the Plio-Quaternary. We present here how we use OSL-thermochronology, a new thermochronometer of exceptionally low closure temperature (about 30°-40°C) (Herman et al subm.), new {U-Th}/He on apatites data, and a glacial erosion model (Herman and Braun 2008) to estimate topographic changes in the Alps in response to glaciations. Because of their low closure temperature, OSL and AHe thermochronology enables quantification of events of less than 1 Ma at very small wavelength of the topography. We collected two vertical profiles, one in the Zermatt Valley (Valais) and one in Maurienne Valley (Savoy). We infer from these results changes in topography, date and quantify relief creation under glacial-interglacial cycles. Cederbom, C.E, et al., Climate induced rebound and exhumation of the European Alps. Geology 32, 709-712 (2000). Champagnac, J.-D., et al., Quaternary erosion-induced isostatic rebound in the western Alps. Geology 35, 195-198 (2007). Ha

  9. OSL dating of fluvial terraces for incision rate estimation and indication of neotectonic activity in Pamir

    Science.gov (United States)

    Fuchs, M. C.; Gloaguen, R.; Krbetschek, M.; Szulc, A.

    2012-04-01

    ThePamir owes its special attraction for geo-scientists to being among Earth's largest intra-continental orogens and to display some of the highest uplift rates as well as to host among the most powerful river systems on the planet. The evolution of the drainage network as a proxy for the landscape's response to tectonic signals provides a powerful tool to study neotectonics. The relation between tectonic forcing and surface response is indicated by structural anomalies (e.g. river-capture, river-reversal or -deflection) and spatial differences of process rates (e.g. incision rates). We combine OSL dating with remote sensing tectonic geomorphology in order to determine the zones of active deformation in the Quaternary. The local drainage system of the study region aligns mainly to the east-west-trending belts of shortening, which results from the ongoing northward propagation of the Indian plate. In contrast the major trunk river, the Panj, is unusual in that it deflects northwards and then doubles back to the southwest, cutting the southern and central Pamir doming and several other major Cenozoic deformation zones. We use fluvial terraces along the deflected north-south orientated part including the doubled back prolongation of the more or less normal orientated Panj. These sediment bodies are used as a geomorphic record to reveal changes in the balance between sediment flux and discharge. Dating these fluvial terraces by OSL provides the burial ages of the sediments indicating periods of sedimentation. The remains of those periods are far from equally distributed and mark the time of local conditions for sedimentation as especially the close neighbourhood of most of the terraces from the two youngest periods demonstrate. Precise measurements of the heights of the dated terraces with respect to the present river level based on relative kinematic GPS quantify the total vertical incision of the river subsequent to the sedimentation and abandonment. Incision rates

  10. Thermally assisted photo transfer OSL from deep traps in Al2O3:C grains exhibiting different TL peak shapes.

    Science.gov (United States)

    Polymeris, George S; Kitis, George

    2012-10-01

    The present work studies the thermally assisted photo transfer OSL (TAPT OSL) signal in the case of Al(2)O(3):C samples showing double-structured main dosimetric TL peaks. The measurement signal provides indirect experimental evidence regarding the presence of deep traps along with one transfer mechanism extremely powerful and efficient. The experimental features of this signal are presented along with those yielded for samples with narrow TL peaks for the sake of comparison. In the framework of a dosimetric characterization, the straightforward relation observed between the TAPT OSL integrated intensity and the dose, even if non-linear, implies that this signal could be effectively used towards dosimetry purposes in the high dose region up to 250 Gy. Furthermore, the study on the influence of the annealing temperature on the TL glow curve shape on Al(2)O(3):C grains is attempted. The variety of glow curve shapes reported especially in the case of single grains is not affected by high temperature annealing, since its effect is dominant even after heating at 1085°C. Thus, this variety should not be correlated to the different deep trap occupancies, but rather be attributed to a possible structural defect. The main dosimetric TL peak af all grains is considered to be a composite of two unambiguously different traps of non-first-order kinetics. The low temperature part of these traps, reaching a maximum at ~190°C is an electron trap and the high temperature part with maximum at ~250°C is a hole trap. TL dose response of Al(2)O(3):C grains presenting double peak structures is presented for the first time in literature, suggesting the usefulness on the applicability of Al(2)O(3):C in the dose regime up to 100 Gy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  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

    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....... Multi-grain quartz OSL signals are dominated by the fast component and response. Single-grain beta dose recovery gave a ratio of 0.97 ± 0.06 (n ¼ 30) with an over-dispersion of 23 ± 8% (CAM). Both the recent known age and the palaeo...

  12. 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......The challenge of accurately estimating the deposition age of incompletely-bleached samples in luminescence dating has motivated developments in the analysis of single grain dose distributions, and a number of statistical approaches have been proposed over the last few years. In this study, we...

  13. 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 <250 micrometer. After that, we removed feldspar, phyllosilicates, and pyrite by performing magnetic separation and acid 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

  14. Simulations of thermally transferred OSL signals in quartz: Accuracy and precision of the protocols for equivalent dose evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pagonis, Vasilis, E-mail: vpagonis@mcdaniel.edu [Physics Department, McDaniel College, Westminster, MD 21157 (United States); Adamiec, Grzegorz [Silesian University of Technology, Institute of Physics, GADAM Centre of Excellence, ul. Krzywoustego 2, 44-100 Gliwice (Poland); Athanassas, C. [Laboratory of Archaeometry, Institute of Materials Science, N.C.S.R. ' Demokritos' , Aghia Paraskevi, Athens153 10 (Greece); Chen Reuven [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Baker, Atlee; Larsen, Meredith; Thompson, Zachary [Physics Department, McDaniel College, Westminster, MD 21157 (United States)

    2011-06-15

    Highlights: > This paper presents extensive numerical simulations of the ReSAR protocol for luminescence dating. > We simulate several experimental versions of the ReSAR protocol and compare their relative accuracy and precision. > Simulations are carried out using a recently published kinetic model for quartz, consisting of 11 energy levels. > Natural doses above 400 Gy are underestimated in the protocols. > Possible sources of this underestimation are investigated. - Abstract: Thermally-transferred optically stimulated luminescence (TT-OSL) signals in sedimentary quartz have been the subject of several recent studies, due to the potential shown by these signals to increase the range of luminescence dating by an order of magnitude. Based on these signals, a single aliquot protocol termed the ReSAR protocol has been developed and tested experimentally. This paper presents extensive numerical simulations of this ReSAR protocol. The purpose of the simulations is to investigate several aspects of the ReSAR protocol which are believed to cause difficulties during application of the protocol. Furthermore, several modified versions of the ReSAR protocol are simulated, and their relative accuracy and precision are compared. The simulations are carried out using a recently published kinetic model for quartz, consisting of 11 energy levels. One hundred random variants of the natural samples were generated by keeping the transition probabilities between energy levels fixed, while allowing simultaneous random variations of the concentrations of the 11 energy levels. The relative intrinsic accuracy and precision of the protocols are simulated by calculating the equivalent dose (ED) within the model, for a given natural burial dose of the sample. The complete sequence of steps undertaken in several versions of the dating protocols is simulated. The relative intrinsic precision of these techniques is estimated by fitting Gaussian probability functions to the resulting simulated

  15. 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......The challenge of accurately estimating the deposition age of incompletely-bleached samples in luminescence dating has motivated developments in the analysis of single grain dose distributions, and a number of statistical approaches have been proposed over the last few years. In this study, we...

  16. TL and OSL dose response and stability properties of various commercially glass samples obtained from Turkey for dosimetric purposes in the UV emission spectral region.

    Science.gov (United States)

    Şahiner, Eren

    2017-10-01

    This paper reports Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) dose response characteristics of ten different commercial glass samples collected from Turkey. Nowadays, glass samples are widely used mostly in objects of everyday life. The study focuses to both TL and OSL dose responses, through a dose region within 1 and 512Gy. Lowest detectable dose limit (LDDL) as well as the respective linearity features of the corresponding dose response curves were studied for both TL and OSL. Moreover, signal reproducibility and fading behaviors have also been studied in detail. For specific samples, the lowest detectable dose was yielded at 2Gy, making thus these samples appropriate for retrospective dosimetry applications. Nevertheless, based on the features reported in the present study, the majority of the samples could be possibly used effectively for dosimetric applications of higher doses in the UV region emission. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. 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

    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...... and natural samples; the results are satisfactory up to ~800 Gy. Resulting quartz OSL and feldspar pIRIR290 ages are in good agreement at least back to ~44 ka; beyond this feldspar pIRIR290 ages are older. The feldspar ages are consistent with the expected age of the S1 palaeosol (MIS 5). There appears...

  18. Use of OSL dating to establish the stratigraphic framework of Quaternary eolian sediments, Anton scarp upper trench, Northeastern Colorado High Plains, USA

    Science.gov (United States)

    Mahan, S.A.; Noe, D.C.; McCalpin, J.P.

    2009-01-01

    This paper contains the results of the optically stimulated luminescence (OSL) dating used to establish stratigraphic ages and relationships of eolian sediments in a trench in northeastern Colorado, USA. This trench was located in the upper face of the Anton scarp, a major topographic lineament trending NW-SE for a distance of 135 km, in anticipation of intersecting near-surface faulting. The trench was 180 m long, 4.5-6.0 m deep, and exposed 22 m of stratigraphic section, most of which dipped gently west and was truncated by gulley channeling at the face of the scarp. No direct evidence of faulting was found in the upper trench. The stratigraphy from the trench was described, mapped and dated using OSL on quartz and potassium feldspar, and 14C obtained from woody material. OSL dating identified two upper loess units as Peoria Loess and Gilman Canyon Loess, deposited between 16 and 30 ka ago. The bottom layers of the trench were substantially older, giving OSL ages in excess of 100 ka. These older ages are interpreted as underestimates, owing to saturation of the fast component of OSL. Using OSL and 14C dating, we can constrain the erosion and down cutting of the scarp face as occurring between 16 and 5.7 ka. As the trenching investigation continues in other parts of the scarp face, the results of this preliminary study will be of importance in relating the ages of the strata that underlie different parts of the scarp, and in determining whether Quaternary faulting was a mechanism that contributed to the formation of this regional geomorphic feature.

  19. Investigation of neutron converters for production of optically stimulated luminescence (OSL) neutron dosimeters using Al{sub 2}O{sub 3}:C

    Energy Technology Data Exchange (ETDEWEB)

    Mittani, J.C.R. [Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072 (United States); Silva, A.A.R. da [Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072 (United States); Vanhavere, F. [SCK.CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Akselrod, M.S. [Landauer, Inc., Stillwater Crystal Growth Division, 723 1/2 Eastgate Rd., Stillwater, OK 74074 (United States); Yukihara, E.G. [Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072 (United States)]. E-mail: eduardo.yukihara@okstate.edu

    2007-07-15

    This paper presents the optically stimulated luminescence (OSL) properties of neutron dosimeters in powder and in the form of pellets prepared with a mixture of Al{sub 2}O{sub 3}:C and neutron converters. The neutron converters investigated were high density polyethylene (HDPE), lithium fluoride (LiF), lithium fluoride 95% enriched with {sup 6}Li ({sup 6}LiF), lithium carbonate 95% enriched with {sup 6}Li ({sup 6}Li{sub 2}CO{sub 3}), boric acid enriched with 99% of {sup 10}B (H{sub 3}{sup 10}BO{sub 3}) and gadolinium oxide (Gd{sub 2}O{sub 3}). The proportion of Al{sub 2}O{sub 3}:C and neutron converter in the mixture was varied to optimize the total OSL signal and neutron sensitivity. The neutron sensitivity and dose-response were determined for the OSL dosimeters using a bare {sup 252}Cf source and compared to the response of Harshaw TLD-600 and TLD-700 dosimeters ({sup 6}LiF:Mg,Ti and {sup 7}LiF:Mg,Ti). The results demonstrate the possibility of developing an OSL dosimeter made of Al{sub 2}O{sub 3}:C powder and neutron converter with a neutron sensitivity (defined as the ratio between the {sup 60}Co equivalent gamma dose and the reference neutron absorbed dose) and neutron-gamma discrimination comparable to the TLD-600/TLD-700 combination. It was shown that the shape of the OSL decay curves varied with the type of the neutron converter, demonstrating the influence of the energy deposition mechanism and ionization density on the OSL process in Al{sub 2}O{sub 3}:C.

  20. Determinação atraves do metodo da dosimetria termoluminescente, das doses de radiação incidentes em orgãos criticos, durante a obtenção de radiografias extra-bucais

    OpenAIRE

    1989-01-01

    Resumo: O presente estudo teve o propósito de determinar o valor de doses de radiação incidentes em determinadas regiões consideradas críticas, de pacientes submetidos a exames radiográficos extra-bucais de interesse na Odontologia. Para isso, foi usada a dosimetria termoluminescente (LiF-700). Os resultados evidenciaram que os níveis de radiação, decorrentes de radiografias extra-bucais realizadas em indivíduos com diversos tipos morfológicos de face, mostram diferenças entre si, sugerindo ...

  1. Multi-method (TL and OSL), multi-material (quartz and flint) dating of the Mousterian site of Roc de Marsal (Dordogne, France): correlating Neanderthal occupations with the climatic variability of MIS 5–3

    DEFF Research Database (Denmark)

    Guerin, Guillaume; Discamps, Emmanuel; Lahaye, Christelle;

    2012-01-01

    Roc de Marsal has yielded numerous remains of Mousterian occupations, including lithics, fauna and combustion features. It was made famous by the discovery of the skeleton of a Neanderthal child. Given the need to date the sequence, TL and OSL were applied on heated flints and quartz, and OSL...

  2. OSL age and stratigraphy of the Strauss sand sheet in New Mexico, USA

    Science.gov (United States)

    Hall, Stephen A.; Goble, Ronald J.

    2015-07-01

    The Strauss sand sheet occurs in south-central New Mexico, USA, and northern Chihuahua, Mexico, covering an area of about 4740 km2. Its chronology is determined by 19 OSL ages. The sand sheet formed primarily during three phases of eolian deflation and deposition, each phase with a separate sand source and under different climatic and environmental circumstances. The first phase of eolian sedimentation occurred 45 to 15 ka with the deposition of unit 1. The sand source for the first phase was beach-related features along the eastern shoreline of pluvial Lake Palomas in Mexico. The glacial-age climate was cool, wet, and windy because of the southern path of the jet stream at that time. After 15 ka, with the onset of warmer conditions of the Bølling-Allerød, the shutting down of the Palomas sand source, and wet conditions of the Younger Dryas, the sand sheet stabilized with weak soil development in unit 1. By 11 ka, the climate shifted to Holocene drying conditions and the second phase of sand accumulation began, forming unit 2; the sand source was the local deflation of the previously deposited unit 1 sand. The sand sheet stabilized again by 1.9 ka with slightly wetter late Holocene climate; a weak soil formed in unit 2 sand. About A.D. 1500 and extending to about A.D. 1850 or later, an A horizon formed on the sand sheet, probably in response to a desert grassland vegetation during the period of wet climate of the Little Ice Age. In an anthropogenic third phase of eolian activity, after A.D. 1850, the vegetation was likely disturbed by overgrazing; and the unit 2 and A horizon (unit 3) sands were deflated, resulting in the deposition of a thin layer of massive eolian sand (unit 4) across the sand sheet. By about A.D. 1900 mesquite shrubs had increased in abundance; and deflated sand, largely from unit 2, began to accumulate around the shrubs, forming coppice dunes (unit 5). Mesquite coppice dunes continued to increase in number and volume during the twentieth

  3. Angular dependence of TL and OSL responses of Al{sub 2}O{sub 3}:C commercial detectors in standard beta radiation beams

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, Patricia L.; Caldas, Linda V.E., E-mail: patrilan@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    The luminescent response of radiation detectors was evaluated by means of the thermoluminescence (TL) and optically stimulated luminescence (OSL) phenomena, for verification of its application in radiation dosimetry. An angular dependence study was performed in this work, using Al{sub 2}O{sub 3}:C commercial detectors, which were exposed to the radiation beams of a {sup 90}Sr +{sup 90}Y source from a beta radiation secondary standard system. The detectors were irradiated with an angle variation from -60° to +60°, and the results obtained using the TL and OSL techniques were within the international recommendation limits. (author)

  4. 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

  5. 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

    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...

  6. Synthesis and TL/OSL properties of a novel high-sensitive blue-emitting LiSrPO4:Eu2+ phosphor for radiation dosimetry

    Science.gov (United States)

    Palan, C. B.; Koparkar, K. A.; Bajaj, N. S.; Soni, A.; Omanwar, S. K.

    2016-07-01

    In this study, a series of Eu2+-doped LiSrPO4 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 LiSrPO4:Eu2+ phosphors were studied. The LiSrPO4:Eu2+ phosphor shows OSL sensitivity about 8 times than that of α-Al2O3:C phosphor and 6 times than that of LiMgPO4:Tb3+, B phosphor. Moreover, TL sensitivity was about 15 times more as compared to α-Al2O3: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 3 σ of background. Also, reusability was also studies, which shows the phosphor can be reusable for 10 cycles with 0.1 % change in OSL output.

  7. Chronology and the upper dating limit for loess samples from Luochuan section in the Chinese Loess Plateau using quartz OSL SAR protocol

    Science.gov (United States)

    Lai, ZhongPing

    2010-01-01

    Luminescence dating of loess older than 100 ka has long been a challenge. It has been recently reported that, using optically stimulated luminescence (OSL) of fine-grained quartz (4-11 μm) extracted from loess, the range of luminescence dating could be pushed to ˜0.6 Ma with OSL ages being in agreement with independent ages [Watanuki, T., Murray, A.S., Tsukamoto, S., 2005. Quartz and polymineral luminescence dating of Japanese loess over the last 0.6 Ma: comparison with an independent chronology. Earth and Planetary Science Letters 240, 774-789]. The aim of this study is to provide a luminescence chronology (20 samples) for the standard Luochuan loess section, and to further examine the upper limit of quartz OSL dating for Chinese loess. The growth curve does not saturate at 700 Gy, and should allow reliable equivalent dose ( De) determination up to at least 400 Gy. However, when compared with independent chronological control, the De that could be treated as reliable is less than ˜230 Gy (corresponding to ˜70 ka in age for Chinese loess), and the De larger than ˜230 Gy should be underestimated. Ages for samples from the lower part of palaeosol S1 are severely underestimated, with the maximum age of 95 ka for a sample from the bottom of this palaeosol, much younger than the expected age of ˜128 ka. The maximum De obtained for sample L9/M, collected from loess layer L9 which is below the Matuyama-Brunhes (B/M) boundary whose age is ˜780 ka, is only 403 Gy which corresponds to an age of 107 ka. The cause of underestimation is not yet clear. The previous results by Watunuki et al. (2005) on the extension of OSL dating of loess to 0.6 Ma is not confirmed. When evaluating the validity of OSL ages in S1, another possibility is to question the already established chronological frame for Luochuan section, which is based on the hypothesis of continuous dust deposition. The assumption of an erosion hiatus between L2 and S1 could make the OSL ages look reasonable

  8. 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.

  9. 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

  10. Online fibre optic OSL in vivo dosimetry for quality assurance of external beam radiation therapy treatments: The ANR-TECSAN Codofer Project; Dosimetrie in vivo par OSL, en ligne par fibre optique, pour l'assurance qualite des traitements par radiotherapie externe: le projet ANR-TECSAN Codofer

    Energy Technology Data Exchange (ETDEWEB)

    Magne, S.; Ferdinand, P. [CEA Saclay, Laboratoire de mesures optiques, CEA LIST, 91191 Gif-sur-Yvette (France); De Carlan, L. [CEA Saclay, Laboratoire national Henri-Becquerel, CEA LIST, 91191 Gif-sur-Yvette (France); Bridier, A.; Isambert, A. [Service de physique, institut Gustave-Roussy, 39, rue Camille-Desmoulins, 94805 Villejuif (France); Hugon, R. [CEA Saclay, Departement capteur, signal et informations, CEA LIST, 91191 Gif-sur-Yvette (France); Guillon, J. [Societe Fimel, 18, rue Marie-et-Pierre-Curie, 92260 Fontenay-aux-Roses (France)

    2010-05-15

    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)

  11. Quantification of fluvial response to tectonic deformation in the Central Pontides, Turkey; inferences from OSL dating of fluvial terraces

    Science.gov (United States)

    McClain, Kevin; Yıldırım, Cengiz; Çiner, Attila; Akif Sarıkaya, M.; Şahin, Sefa; Özcan, Orkan; Güneç Kıyak, Nafiye; Öztürk, Tuǧba

    2017-04-01

    From Late Miocene to present, Anatolia's rapid counterclockwise movement, which increases in velocity towards the Hellenic Arc, has formed the North Anatolian Fault (NAF), a dextral transform fault along the Anatolia-Eurasia plate boundary and the northern margin of the Central Anatolian Plateau (CAP). A zone of transpression referred to as the Central Pontides exists between the broad restraining bend of the NAF and the Black Sea Basin, uplifting what is interpreted as a detached flower structure. Dating of Quaternary landforms in the eastern flank of the Central Pontides has helped to understand its recent deformation. However, in the western flank of the Central Pontides there is an absence of Quaternary studies, relatively quiet modern seismicity, and difficulties locating or observing fault scarps. This led us to use optically stimulated luminescence dating (OSL-dating) of fluvial terrace sediments and the study of geomorphic features to gain insight into the influence of climate and tectonics on landscape evolution of this area. In this area, the Filyos River crosses the Karabük Fault (reverse fault) and deeply incises a gorge through the Karabük Range before flowing towards the Black Sea. In the gorge an abundance of indicators of tectonic deformation were mapped, such as hanging valleys, wind gaps, bedrock gorges, landslides, steep V-shaped channels, tilted basins, as well as fluvial strath terraces. In particular, strath terraces of at least 8 levels within just 1.5 km of horizontal distance were examined. We used OSL-dating to estimate five deposition ages of fluvial strath terrace sediments, leading to an estimation of incision and uplift rates over time. Using three samples per terrace with strath elevations of 246 ± 0.2 m, 105.49 ± 0.2 m, 43.6 ± 0.2 m, 15.3 ± 0.2 m and 3.6 ± 0.2 m above the Filyos River, we determined corresponding ages of 841 ± 76 ka, 681 ± 49 ka, 386 ± 18 ka, 88 ± 5.1 ka and 50.9 ± 2.8 ka. Incision rates over time (oldest

  12. 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

    assistance energy required for IR stimulation (1.49 eV; 830 nm) of the fast component is calculated to be 0.41 +/- 0.02 eV. However, the elevated temperature IRSL of quartz has a poor signal-to-noise ratio; hence a single-aliquot regenerative-dose (SAR) protocol based on a differential-OSL signal (the...... sensitivity changes arising from holding the samples at high temperatures for long periods (similar to 1500 s). The resulting equivalent dose values, and those from a conventional SAR protocol based on the initial-OSL signal, are compared with the expected doses for several samples. We observe...... from samples dominated by the fast component using both protocols. Finally, the implications are discussed for dosimetry using quartz. (C) 2004 Elsevier Ltd. All rights reserved....

  13. Fundamental study of nanoDot OSL dosimeters for entrance skin dose measurement in diagnostic x-ray examinations

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Tohru; Kobayashi, Ikuo [Nagase Landauer, Ltd., Tsukuba (Japan); Hayashi, Hiroaki; Takegami, Kazuki; Okino, Hiroki; Kimoto, Natsumi; Maehata, Itsumi [Tokushima University, Tokushima (Japan)

    2016-09-15

    In order to manage the patient exposure dose in X-ray diagnosis, it is preferred to evaluate the entrance skin dose; although there are some evaluations about entrance skin dose, a small number of report has been published for direct measurement of patient. We think that a small-type optically stimulated luminescence (OSL) dosimeter, named nanoDot, can achieve a direct measurement. For evaluations, the corrections of angular and energy dependences play an important role. In this study, we aimed to evaluate the angular and the energy dependences of nanoDot. Materials and Methods We used commercially available X-ray diagnostic equipment. For angular dependence measurement, a relative response of every 15 degrees of nanoDot was measured in 40-140 kV X-ray. And for energy dependence measurement, mono-energetic characteristic X-rays were generated using several materials by irradiating the diagnostic X-rays, and the nanoDot was irradiated by the characteristic X-rays. We evaluated the measured response in an energy range of 8.1-75.5 keV. In addition, we performed Monte-Carlo simulation to compare experimental results. The experimental results were in good agreement with those of Monte-Carlo simulation. The angular dependence of nanoDot was almost steady with the response of 0 degrees except for 90 and 270 degrees. Furthermore, we found that difference of the response of nanoDot, where the nanoDot was irradiated from the randomly set directions, was estimated to be at most 5%. On the other hand, the response of nanoDot varies with the energy of incident X-rays; slightly increased to 20 keV and gradually decreased to 80 keV. These results are valuable to perform the precise evaluation of entrance skin dose with nanoDot in X-ray diagnosis. Conclusion The influence of angular dependence and energy dependence in X-ray diagnosis is not so large, and the nanoDot OSL dosimeter is considered to be suitable dosimeter for direct measurement of entrance surface dose of patient.

  14. A comparison of TT-OSL and post-IR IRSL dating of coastal deposits on Cap Bon peninsula, north-eastern Tunisia

    DEFF Research Database (Denmark)

    Thiel, Christine; Buylaert, Jan-Pieter; Murray, Andrew S.

    2012-01-01

    In this study thermally transferred (TT) OSL and post-IR elevated temperature IRSL (290 °C) (pIRIR290) dating are applied to deposits covering coastal terraces on the Cap Bon peninsula, Tunisia. Both methods perform well under standard performance tests; dose recovery tests using a modern analogue...... that the geological setting on Cap Bon is not as simple as previously suggested....

  15. 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.

  16. 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.

  17. 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.

  18. Optically stimulated luminescence (OSL) response of Al2O3:C, BaFCl:Eu and K2Ca2(SO4)3:Eu phosphors.

    Science.gov (United States)

    Kumar, Pratik; Bahl, Shaila; Sahare, P D; Kumar, Surender; Singh, Manveer

    2015-12-01

    This paper investigates the optically stimulated luminescence (OSL) response of BaFCl:Eu and K2Ca2(SO4)3:Eu phosphors for different doses and bleaching durations. The results have also been compared with the commercially available Landauer Al2O3:C (Luxel®) dosemeter. Nanocrystalline K2Ca2(SO4)3:Eu is known to be a sensitive thermoluminescent phosphor, but its OSL response is hardly reported. At first, pellets of nanocrystalline K2Ca2(SO4)3:Eu powder were prepared by adding Teflon as a binder. Their OSL signal was compared with that of the material in pure form, i.e. without adding the binder (in 100:1 ratio). It was observed that adding the binder does not appreciably affect the OSL intensity. On comparison with the commercially available Al2O3:C from Landauer, it was found that K2Ca2(SO4)3:Eu is around 15 times less sensitive than Al2O3:C. 'Homemade' BaFCl:Eu phosphor has also been studied. The intensity of BaFCl:Eu was ∼20 times more than the standard Al2O3:C dosemeter and ∼200 times more sensitive than K2Ca2(SO4)3:Eu in the dose range of 13-200 cGy. OSL dosemeters are believed to give luminescence signal even if they are read before, i.e. multiple reading may be possible under suitable conditions after single exposure. This was also checked for all the prepared dosemeters and it was found that Al2O3:C showed the least decrease of Eu of 15 % and K2Ca2(SO4)3:Eu with 20 %. Finally, Al2O3:C and BaFCl:Eu phosphors were also studied for their optical bleaching durations to which the respective signals get completely removed so that the phosphor can be re-used. It was observed that BaFCl:Eu is bleached faster and more easily than Al2O3:C.

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

    Science.gov (United States)

    Polymeris, G S; Giannoulatou, V; Kyriakidou, A; Sfampa, I K; Theodorou, G S; Şahiner, E; Meriç, N; Kitis, G; Paraskevopoulos, K M

    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 (SiO2 45, Na2O 24.5, CaO 24.5, P2O5 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 20-40μm 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 16min 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 of the 58S sol-gel bioactive glass

  20. Middle-Late Holocene earthquake history of the Gyrtoni Fault, Central Greece: Insight from optically stimulated luminescence (OSL) dating and paleoseismology

    Science.gov (United States)

    Tsodoulos, Ioannis M.; Stamoulis, Konstantinos; Caputo, Riccardo; Koukouvelas, Ioannis; Chatzipetros, Alexandros; Pavlides, Spyros; Gallousi, Christina; Papachristodoulou, Christina; Ioannides, Konstantinos

    2016-09-01

    The south-dipping Gyrtoni Fault defines the northeastern boundary of the Middle-Late Quaternary Tyrnavos Basin, Central Greece. The recognition and recent tectonic activity of the fault were previously based on mapping, remote sensing analyses and electrical resistivity tomography studies. To understand the Holocene seismotectonic behavior of the Gyrtoni Fault we excavated two paleoseismological trenches. To estimate the timing of past earthquakes using luminescence dating, we obtained twenty five fluvial-colluvial sediment and pottery samples from both the upthrown and the downthrown fault blocks. We applied the Optically Stimulated Luminescence (OSL) dating to coarse grain quartz using the single-aliquot regenerative-dose (SAR) protocol. Our investigations of luminescence characteristics using various tests confirmed the suitability of the material for OSL dating. We found that the estimated OSL ages were internally consistent and agreed well with the available stratigraphical data, archaeological evidence and radiocarbon dates. The performed paleoseismological analysis emphasized the occurrence of three surface faulting events in a time span between 1.42 ± 0.06 ka and 5.59 ± 0.13 ka. Also, we recognized an earlier faulting event (fourth) has been also recognized to be older than 5.59 ± 0.13 ka. The mean throw per event value of 0.50-0.60 m could correspond to a ca. Mw 6.5 earthquake. An average fault slip rate of 0.41 ± 0.01 mm/a and an average recurrence time of 1.39 ± 0.14 ka were also estimated. Our results suggest that the elapsed time from the most recent event (minimum age 1.42 ± 0.06 ka) is comparable with the mean return period.

  1. 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.

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

    Science.gov (United States)

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

    2015-03-01

    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.

  3. 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....... These coefficients account for changes in RL and OSL signals with changes in temperature during irradiation and stimulation. The work was primarily based on a set of automated laboratory measurements carried out using 50 kV X-rays (0–3 Gy) with delays in the range of 10–3600 s and temperatures in the range of 10...

  4. Precision of RL/OSL medical dosimetry with fiber-coupled Al2O3:C: Influence of readout delay and temperature variations

    DEFF Research Database (Denmark)

    Andersen, C.E.; Edmund, J.M.; Damkjaer, S.M.S.

    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....... These coefficients account for changes in RI and OSL signals with changes in temperature during irradiation and stimulation. The work was primarily based on a set of automated laboratory measurements carried out using 50 kV X-rays (0-3 Gy) with delays in the range of 10-3600 s and temperatures in the range of 10...

  5. Storage mechanism and OSL-readout possibility of Li{sub 2}B{sub 4}O{sub 7}:Mn (TLD-800)

    Energy Technology Data Exchange (ETDEWEB)

    Danilkin, M., E-mail: danilkin@ut.e [Faculty of Science and Technology, University of Tartu, Vanemuise 46, 51014 Tartu (Estonia); Jaek, I.; Kerikmaee, M.; Lust, A.; Maendar, H.; Pung, L.; Ratas, A.; Seeman, V. [Faculty of Science and Technology, University of Tartu, Vanemuise 46, 51014 Tartu (Estonia); Klimonsky, S.; Kuznetsov, V. [Faculty of Natural Sciences, D. Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125047 Moscow (Russian Federation)

    2010-03-15

    Thermoluminescence, dose dependences, and EPR of Mn-doped lithium tetraborate are studied. Mn is shown not to change a charge state during energy storage and release. Mn{sup 2+} amount decreases only at very high doses. The amount of Mn{sup 2+} depends on the sintering temperature and increases with temperature increase due to reduction of Mn from a higher oxidation state. X-irradiation creates optical absorption bands in Li{sub 2}B{sub 4}O{sub 7}:Mn. Optical stimulation in the UV band is effective for OSL-readout and destroys dosimetric TL peaks. The model of energy storage and release is discussed.

  6. 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.

  7. 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...... 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 +/- 130 nm in the case of single-aliquot and 532 nm in the case of single grains, could...

  8. Paleoseismology of Upper Plate Faults in the Chilean Covergent Margin: Insights from 10BE and OSL Dating

    Science.gov (United States)

    Gonzalez, G.; Cortes, J. A.; Binnie, S.; Robinson, R.; Toledo, C.

    2010-12-01

    The Chilean convergent margin is the locus of most of the largest subduction earthquakes recorded in history. Slip deficit along this plate boundary is absorbed by elastic deformation of the upper plate. Numerical models and geodetic data suggest a fully elastic behaviour of the overriding crust and that deformation is balanced between inter- and co-seismic phases earthquake cycle; thus, non permanent deformation should be expected. However,the topographic surface of the coastal area, especially in the arid northern region of Chile (18°-26°S), shows clear evidences of permanent deformation expressed as kilometric-long fault scarps produced by normal faults. It suggests that normal faulting is a regional-scale extended process characteristic of the near surface structure of the upper plate. Some unanswered, yet critical, questions in this plate boundary are the present activity of these faults and the causal relationship between them and the subduction earthquake cycle. In order to answer these questions we conducted a paleoseismological project aimed at understanding the most recent activity of the upper plate faults in northern Chile. Here, we present the first results of two main faults located nearby the city of Antofagasta and the Mejillones Peninsula. One of these faults corresponds to the main strand of the Atacama Fault System whereas the other is the Mejillones Fault. At least 18 trenches were excavated for paleoseismological logging across these faults. OSL samples were extracted from wedge shaped colluvium and 10Be exposures ages were determined in alluvial surfaces displaced by the faults. Our results indicate that fault scarps were formed during Late Pleistocene-Holocene with a fault slip rate of 0.3 to 0.6 m/ky. Furthermore, we demonstrated that these faults generated large Mw~7 earthquakes with recurrence interval of many thousands years. In the Mejillones Fault, we determined that the elapsed time since the last large earthquake Mw~6.7 is ~3 ky BP

  9. 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.)

  10. 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

  11. Single-grain OSL chronologies for Middle Palaeolithic deposits at El Mnasra and El Harhoura 2, Morocco: implications for Late Pleistocene human-environment interactions along the Atlantic coast of northwest Africa.

    Science.gov (United States)

    Jacobs, Zenobia; Roberts, Richard G; Nespoulet, Roland; El Hajraoui, Mohammed Abdeljalil; Debénath, André

    2012-03-01

    Optically stimulated luminescence (OSL) measurements were made on individual, sand-sized grains of quartz from Middle Palaeolithic deposits at two cave sites (El Harhoura 2 and El Mnasra) on the Atlantic coast of Morocco. We were able to calculate OSL ages for 32 of the 33 samples collected from the Middle Palaeolithic deposits, including the earliest and latest Aterian levels at both sites. These ages reveal periods of occupation between about 110 and 95 ka (thousands of years ago), and at ~75 ka. A late Middle Palaeolithic occupation of El Harhoura 2 is also recorded at ~55 ka. Our single-grain OSL chronologies largely support previous age estimates from El Mnasra and other sites along the Atlantic coast of Morocco, but are generally more precise, reproducible and stratigraphically more coherent (i.e., fewer age reversals). We compare the single-grain ages for El Harhoura 2 and El Mnasra with those obtained from single- and multi-grain OSL dating of Middle Palaeolithic deposits in the nearby sites of Contrebandiers and Dar es-Soltan 1 and 2, and with records of past regional environments preserved in sediment cores collected from off the coast of northwest Africa. A conspicuous feature of the new chronologies is the close correspondence between the three identified episodes of human occupation and periods of wetter climate and expanded grassland habitat. Owing to the precision of the single-grain OSL ages, we are able to discern gaps in occupation during Marine Isotope Stages 5 and 4, which may represent drier periods with reduced vegetation cover. We propose that these climatic conditions can be correlated with events in the North Atlantic Ocean that exert a major control on abrupt, millennial-scale fluctuations between wet and dry periods in northwest and central North Africa.

  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......, Infrared Stimulated Luminescence (IRSL) at 50°C, and post-IR elevated temperature (225°C) IRSL signals from K-feldspar. All signals pass the routine tests associated with the Single Aliquot Regenerative (SAR) protocol, including the recycling ratio, recuperation, and dose recovery tests. The equivalent...... of anomalous fading to a great extent, the resulting age cannot be regarded as necessarily accurate because of the limitations of the fading correction model used, and the absence of independent age control for the old samples. Nevertheless, our luminescence ages provide the first age constraints...

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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

    2016-09-01

    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.

  18. 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

  19. Causal links between Nile floods and eastern Mediterranean sapropel formation during the past 125 kyr confirmed by OSL and radiocarbon dating of Blue and White Nile sediments

    Science.gov (United States)

    Williams, M. A. J.; Duller, G. A. T.; Williams, F. M.; Woodward, J. C.; Macklin, M. G.; El Tom, O. A. M.; Munro, R. N.; El Hajaz, Y.; Barrows, T. T.

    2015-12-01

    It has long been hypothesised that beds of highly organic mud or sapropels seen in marine sediment cores retrieved from the floor of the eastern Mediterranean accumulated during times of high Nile fluvial discharge. Our recent fieldwork in the valleys of the Blue Nile, the White Nile and the main Nile has for the first time revealed a sequence of extreme flood episodes synchronous with sapropel units S5 (124 kyr), S4 (102 kyr), S3 (81 kyr), S2 (55 kyr) and S1 (13.5-6.5 kyr). There are more weakly defined links with Nile floods and sapropel units S9 (240 kyr), S8 (217 kyr), S7 (195 kyr), S6 (172 kyr), but the dating error terms are too large to allow us to be too definite. During times of extreme floods over the past 125 kyr, wide distributary channels of the Blue Nile flowed across the Gezira alluvial fan in central Sudan and transported a bed load of sand and gravel into the lower White Nile valley. The sands were reworked by wind to form source-bordering dunes, all of which contain heavy minerals of Ethiopian provenance. These source-bordering dunes were active at 115-105 kyr, 60 kyr and 12-7 kyr, all times of extreme Blue Nile floods. The flood and dune sediments were dated using a combination of optically stimulated luminescence (OSL) and radiocarbon analyses. The Quaternary record of Nile floods discussed here shows a precessional signal and reflects episodes of stronger summer monsoon and more northerly seasonal movement of the ITCZ, linked to times of higher insolation in northern tropical latitudes. Progressive aggradation of Holocene Nile channels in northern Sudan has had a profound influence upon human settlement in the last 8 kyr.

  20. 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.

  1. 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

  2. 新疆昆仑山北坡黄土细颗粒混合矿物IRSL,[post-IR]OSL和细颗粒石英OSL测年初步研究%PRELIMINARY STUDIES ON DATING USING IRSL AND [ POST-IR] OSL SIGNALS FROM FINE-GRAINED POLYMINERALS AND OSL SIGNAL FROM FINE-GRAINED QUARTZ IN LOESS AT NORTHERN SLOPE OF KUNLUN MTS.,XINJIANG

    Institute of Scientific and Technical Information of China (English)

    张克旗

    2012-01-01

    使用感量校正多测片再生(SMAR)法对新疆昆仑山北坡的12个黄土样品的细颗粒混合矿物和细颗粒石英进行了等效剂量(De)的测量.测试结果显示,该地区黄土的[ post-IR]OSL和OSL信号强度相对于黄土高原的样品偏低,初步认为与物源不同及粉尘堆积和堆积后经受的风化作用微弱有关.细颗粒混合矿物的IRSL等效剂量值基本上小于其细颗粒石英OSL的,反映出长石存在明显的异常衰减现象;[post-IR] OSL信号主要来自于长石,用于测年需谨慎;细颗粒石英OSL更适合用于对该地区黄土的测年.%The equivalent doses of fine-grained polymineials and OSL signal from fine-grained quartz were measured by using SMAR protocol to 12 loess samples from the northern slope of Kunlun Mts.,Xinjiang. 8 of the 12 samples were collected from a loess section, which is 84m thick and located in a terrace, southwest of Aqiang township (36°23'30"N,81°54'57"E;2670m a. s. 1. )in Yutian County,and the other 4 samples were collected from terraces (36°15'52"~36°16'35"N,81°29'28" ~ 81°30'35"E;2100 -2120m) at the west bank of the Keriya River. The results show that the intensities of [ post-IR ] OSL and OSL signals are lower than those of the loess samples from the Loess Plateau, which can be related preliminarily to the source differences between the two kinds of loess. It is also probable that the weak weathering of dust during accumulating and after accumulation make the intensity differences. These two factors resulted in the differences of the content and types of minerals between the two areas, as well as a different sensitivity of luminescence signals. The weak signals mean a low signal to noise ratio when a young sample is measured,which will make a low reliability of equivalent dose(De) .The obvious anomalous fading of IRSL signals from feldspars was observed,thus it must be cautious to use the signal to date a sample,which will result in a fact that its De is less

  3. Rastreabilidade das referências metrológicas em dose absorvida na água do Programa de Qualidade em Dosimetria Traceability of metrologic references of dose absorbed to water used in a Dosimetry Quality Assurance Program

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo de Almeida

    2005-06-01

    Full Text Available OBJETIVO: Este trabalho tem por objetivo apresentar a estrutura solidamente estabelecida de rastreabilidade dos padrões ionométricos e do sistema de medidas com dosímetros termoluminescentes, como parte da confiabilidade do Programa de Qualidade em Dosimetria (PQD, que visa a garantir o mais elevado nível de exatidão às suas medidas. MATERIAIS E MÉTODOS: A exemplo de outros programas, usaram-se dosímetros termoluminescentes (DTL 937 na forma de pó, colocados em uma cápsula de plástico, em "kits" específicos para cada aplicação, os quais foram enviados, por via postal, aos centros participantes. RESULTADOS: Os resultados da intercomparação realizada entre o Laboratório de Ciências Radiológicas da Universidade do Estado do Rio de Janeiro e o EQUAL-ESTRO para o feixe de raios gama de 60Co, expressos para (1sigma, e os resultados das medidas de dose absorvida, obtidos com as câmaras dp Programa EQUAL e as câmaras do PQD, apresentaram discordância menor que 0,5%. CONCLUSÃO: Dos resultados conclui-se que o PQD alcançou o nível desejado de confiabilidade, necessário à implementação do Programa.OBJECTIVE: To present the solidly established traceability structure for ionometric standards and for thermoluminescent dosimetry system that ensures reliability of the Dosimetry Quality Assurance Program and is aimed to certify the highest level of accuracy of the measurements. MATERIALS AND METHODS: Thermoluminescent powder dosimeters (DTL 937 placed into plastic capsules and packed in specific kits for each intended application were mailed to the participant centers. RESULTS: The results of the intercomparisons performed between "Laboratório de Ciências Radiológicas da Universidade do Estado do Rio de Janeiro" and EQUAL-ESTRO for the beam of 60Co gamma rays, expressed for (1sigma, and the results of the dose absorbed measurements obtained with the chambers of the Program EQUAL and the chambers of the Dosimetry Quality Assurance

  4. 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

  5. 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

  6. 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)

  7. 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

    Science.gov (United States)

    Şahiner, Eren; Meriç, Niyazi; Polymeris, George S.

    2017-02-01

    Equivalent dose estimation (De) 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 De 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 De 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 De 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 interesting that most of De values yielded using different luminescence signals agree with each other and ESR Ge center has very large D0 values. The results presented above highly support the argument that the stability and the initial ESR signal of the Ge center is highly sample-dependent, without any instability problems for the cases of quartz resulting from fault gouge.

  8. OSL Dating of Fault Collapse Wedge Using SAR Method: Taking the Xitian Trench of Xinding Basin, Shanxi as an Example%断层崩积楔单片再生法光释光测年:以山西忻定盆地西田探槽为例

    Institute of Scientific and Technical Information of China (English)

    赵俊香; 任俊杰; 于慎谔; 张世民; 丁锐

    2011-01-01

    In order to detect the degree of optically stimulated luminescence (OSL) signal bleaching of sediments in each sites of the fault collapse wedge and its formation age, a method of middle-grain single-aliquot regenerative-dose(SAR) procedure was used to implement OSL dating for the four samples from three sites of the fault collapse wedge in Xitian trench of Xinding basin, Shanxi.A representative sample was chosen to analyze the relationship among equivalent dose ( DE ), LN/TN, recycling ratio, recuperation and preheat temperature.The results reveal that the aliquots need go through preheating at 260 ℃ for 10 s.For the four samples, the recycling ratio values of aliquots are almost between 0.9 and 1.1 and the recuperation values are below 5%,which indicates that the procedure of SAR method can successfully correct the OSL sensitivity change during measurement and the equivalent dose is creditable.The equivalent dose distribution and cumulation frequency of samples are analyzed; it can be found that the samples from palaeotopography surface and deluvium are bleaching equally and those from colluvium are worse.The approximate equivalent dose of the colluvium samples can be derived with cumulation frequency and at last, the formation age of this fault collapse wedge is measured as 27.09 ±0.71 ka.%为了研究断层崩积楔各部位沉积物光释光信号晒退情况及崩积楔形成年龄,利用中颗粒石英(63~90μm)单片再生法(SAR)对山西忻定盆地西田探槽断层崩积楔3个部位的4个样品进行光释光(OSL)定年.选择一代表性样品(08-OSL-22)进行等效剂量(DE)、LN/TN、循环比率、回授率与预热温度的关系分析,结果表明预热温度260℃、预热时间10 s为样品最佳预热条件.4个样品的测片循环比率基本在0.9~1.1之间,回授率均小于5%,表明所采用的中颗粒SAR法流程可以很好地校正测量过程中产生的释光感量变化,其等效剂量可信.利用等效剂量分布直

  9. 黄河中游河谷地区三种粒径石英的光释光测年对比%Comparative study of OSL dating on different particle-size of quartz in the middle Yellow River valley region

    Institute of Scientific and Technical Information of China (English)

    顾洪亮; 周亚利; 黄春长; 王恒松; 庞奖励; 查小春

    2011-01-01

    The sediment samples from the Holocene loess-soil proifles which had slackwater deposition of overbank flooding in the Jinghe and Luohe Rivers were OSL dated by using the single aliquot regenerative-dose (SAR) protocol. Purified quartz grains of 4~11 μm, 40~63 μm and 90~125 μm fractions were studied comparatively. The results showed that silt-size and sand-size quartz grains can be puriifed with the treatment using lfuorosilicic acid and hydrolfuoric acid. With this method,the quartz grains of 40~63 μm were obtained much more. The relative standard deviation (RSD) of equivalent dose varied between 2.7%~ 9% for the quartz grains of 40~63 μm. This is smaller than that from the quartz grains of 4~11 μm and 90~125 μm fraction. The De values show anormal distribution for the40~63 μm fraction. The OSL ages measured from 4~11 μm fraction are often older, and from 90~125 μm fraction are smaller.The OSL ages measured from40~63 μm fraction are very close to the archaeological ages for the sample from a same level. The experiment shows that level of natural OSL of the sample normalized by the test dose is relatively concentrated. Thus, quartz grains in the 40~63 μm fraction from the loess-soil in the middle reaches of the Yellow River is suitable for OSL dating by using the single aliquot regenerative-dose (SAR) protocol, so as to provide more reliable data for the Palaeolfoods events.%利用光释光测年(OSL)技术当中的单片再生剂量法(SAR),测定了黄河中游泾河和洛河河谷含特大古洪水滞流沉积物夹层的全新世黄土-古土壤沉积物的年龄。通过对前处理分离提纯三种不同粒径石英样品的测定研究,发现利用氟硅酸和氢氟酸两者结合溶蚀该研究区域的中-粗颗粒石英的方法,提纯石英颗粒样品的效果比较好,且分离获得的40~63μm石英颗粒量最多。相对90~125μm和4~11μm,40~63μm石英的等效剂量相对标准偏差(RSD)最小,为2.7%~9%

  10. Reproducibility Experiment of OSL and TL Dosimeter

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Reproducibility is an important property of personal dosimeter. It not only can indicate the stability of dosimeter, appraise the precision and accuracy of measured value, but also can evaluate the

  11. Experience with the SARA OSL method

    DEFF Research Database (Denmark)

    Mejdahl, V.; Bøtter-Jensen, L.

    1997-01-01

    on the added dose is shown. Advantages of the SARA method is discussed and results obtained using this method for 15 archaeological samples are compared with TL results. A correlation coefficient of 0.967 was found. The test also included comparison of a SARA dare with an archaeomagnetic date for a brick kiln....... Identical results were obtained (1795 +/- 20 AD and 1800 +/- 20 AD, respectively). Similarly. SARA results for 14 sediments are compared with results obtained by TL and IRSL (multiple aliquots)and here the resulting correlation coefficient was 0.983. (C) 1997 Elsevier Science Ltd....

  12. 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.

  13. The Mode and Operation Mechanism of OSL Morality Testing of Administrative Leaders ---Based on An Investigation of Administrative Leaders' Morality Testing Practice%领导干部的OSL品德测评模式及其运行机制——基于部分省市党政干部品德测评实践的思考

    Institute of Scientific and Technical Information of China (English)

    萧鸣政; 吴新辉

    2012-01-01

    德才兼备以德为先,一直是我们国家的人才政治原则。本文在回顾国家相关文件政策与分析当前党政领导干部品德测评问题与实践的基础上,基于品德的资本性、可测量性与可开发性,从人力资源开发的视角,提出了包含“评价、任用、开发”的一体化的OSL动态测评模式,并对这种测评模式提出的背景与原因,内涵、结构及其运行机制进行了相关的分析。文章认为,品德测评不是目的,目的是要通过品德测评来提升领导干部的品德素养。本文设计的OSL测评模式,不仅仅在于对领导干部品德行为的养成效果进行评定,而且这种有组织有计划的品德行为测评本身模式具有开发的功效,能够对领导干部的行为养成进行反馈、调节与引领。%Having both ability and morality, and morality first have been an important principle in China's human resources management. From a human resource development perspective, the moral characters are capital, measurable and developable. Based on reviewing national related policy documents and investigating into the present practice and problems of administra- tive leaders' moral character assessment, the research put forward an OSL integrated dynamic testing model which consists of three aspects of evaluation, appointment and development. The proposition background and reasons, contents, structures and operation mechanism of the OSL model were discussed. The authors argue that morality testing is not the goal, the pur- pose is to improve administrative leaders' moral quality by the morality testing. As a kind of organized and designed moral behavior assessment program, the OSL testing model constructed in this research, can not only be appraised but also be circulated.

  14. Monte Carlo simulation on teaching of luminescence and excited states decay kinetics; Simulacao Monte Carlo no ensino de luminescencia e cinetica de decaimento de estado excitado

    Energy Technology Data Exchange (ETDEWEB)

    Winnischofer, Herbert; Araujo, Marcio Peres de; Dias Junior, Lauro Camargo; Novo, Joao Batista Marques [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil)

    2010-07-01

    A software based in the Monte Carlo method have been developed aiming the teaching of important cases of mechanisms found in luminescence and in excited states decay kinetics, including: multiple decays, consecutive decays and coupled systems decays. The Monte Carlo Method allows the student to easily simulate and visualize the luminescence mechanisms, focusing on the probabilities of the related steps. The software CINESTEX was written for FreeBASIC compiler; it assumes first-order kinetics and any number of excited states, where the pathways are allowed with probabilities assigned by the user. (author)

  15. System for X-Ray excited optical luminescence (XEOL) measurements; Sistema para realizacao de medidas de luminescencia com excitacao por raios X

    Energy Technology Data Exchange (ETDEWEB)

    Cebim, Marco Aurelio; Oliveira, Higor Henrique de Souza; Barelli, Nilso; Davolos, Marian Rosaly [UNESP, Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Quimica Geral e Inorganica

    2011-07-01

    In this work is presented a versatile system for X-ray excited optical luminescence (XEOL) measurements. The apparatus was assembled from a sample holder connected to an optical fiber responsibly for the acquisition of the scintillation signal. The spectrum is registered with a CCD coupled in a spectrograph provided with diffraction gratings. The system performance was analyzed by exciting GdAlO3:Eu{sup 3+} 3.0 at.% with X-rays from a diffractometer and measuring the emission spectra. The system can be used to obtain precise and reliable spectroscopic properties of samples with various conformations without the loss of the required safety when dealing with ionizing radiations. (author)

  16. 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)

  17. Monte Carlo dosimetry in CT; Dosimetria Monte Carlo en CT

    Energy Technology Data Exchange (ETDEWEB)

    Miro Herrero, R.

    2015-07-01

    Computed tomography explorations ITC) contribute a high percentage of the total radiation dose absorbed by the population exposed to medical examination. Since the number of CT scans performed has grown exponentially in recent years, concerns about their long-term effects on the patient's health has also increased. However, in order to establish a relationship between the absorbed dose and its side effects, it is necessary to perform a calculation accurate dosimetry radiation protection international institutions have confirmed that the best indicator of risk is dose to organs. (Author)

  18. 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)

  19. 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)

  20. 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)

  1. 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)

  2. 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)

  3. Dosimetry in nuclear power plants; Dosimetria en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lastra B, J. A. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

    2008-12-15

    To control the occupationally exposed personnel dose working at the Laguna Verde nuclear power plant, two types of dosemeters are used, the thermoluminescent (TLD) which is processed monthly, and the direct reading dosemeter that is electronic and works as daily control of personal dose. In the case of the electronic dosemeters of direct reading conventional, the readings and dose automatic registers and the user identity to which he was assigned to each dosemeter was to carry out the restricted area exit. In activities where the ionizing radiation sources are not fully characterized, it is necessary to relocate the personal dosemeter or assigned auxiliary dosemeters (TLDs and electronics) to determine the dose received by the user to both whole body and in any specific area of it. In jobs more complicated are used a tele dosimetry system where the radiation protection technician can be monitoring the user dose to remote control, the data transmission is by radio. The dosimetry activities are documented in procedures that include dosemeter inventories realization, the equipment and dosemeters calibration, the dosimetry quality control and the discrepancies investigation between the direct reading and TLD systems. TLD dosimetry to have technical expertise in direct and indirect dosimetry and two technicians in TLD dosimetry; electronic dosimetry to have 4 calibration technicians. For the electronic dosemeters are based on a calibrator source of Cesium-137. TLD dosemeters to have an automatic radiator, an automatic reader which can read up to 100 TLD dosemeters per hour and a semiautomatic reader. To keep the equipment under a quality process was development a process of initial entry into service and carried out a periodic verification of the heating cycles. It also has a maintenance contract for the equipment directly with the manufacturer to ensure their proper functioning. The vision in perspective of the dosimetry services of Laguna Verde nuclear power plant includes having a dosimetry laboratory of world class, accredited by the National Voluntary Laboratory Accreditation (USA) , certification to ISO- 17025, and classified into types radiation than those already made. (Author)

  4. 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)

  5. THE RELATIONSHIP BETWEEN ENVIRONMENTAL CHANGES AND HUMAN ACTIVITIES DURING THE MEDIEVAL WARM PERIOD AND THE LITTLE ICE AGE IN OTINDAG SANDLAND BY OSL DATING%光释光测年揭示浑善达克沙地中世纪暖期和小冰期环境变迁与人类活动的关系

    Institute of Scientific and Technical Information of China (English)

    张小艳; 周亚利; 庞奖励; 鹿化煜; 黄春长; 周亮; 顾洪亮

    2012-01-01

    Otindag sandland is located in the middle of Inner Mongolia Plateau ( 112°22' ~ 117°57'N, 41°56' ~ 44°24'E) ,with its present environment is arid to semiarid. The climate is mainly controlled by the East Asian monsoon atmospheric circulation in this region. The earth surface processes,such as dune systems,are sensitive to both climatic changes and human impacts. In order to better understand the interaction of these factors in Otindag sandland during the Medieval Warm Period and the Little Ice Age, optically stimulated luminescence dating(OSL) has been used to obtain ages of five typical dune sediment sequences, which are LQD (42. 26°N, 116. 13 °E) , S308-132km( 42. 39°N, 115. 39°E), HSZN (42. 08°N, 116.44°E), DLGES (43. 56°N, 115. 68°E) and JPW-A (43.24°N,117.45°E) ,with the thickness as 2. 0m, 1. 4m, 3. 0m,2. 2m and 0. 8m, respectively. OSL dating on quartz grains at the size of 90 - 150u,m were carried out by using the single aliquot regenerative-dose ( SAR) protocol. Combined with the characteristics of grain-size distribution, magnetic susceptibility, ignition loss from the sediment and the pottery sherds which were found in LQD and JPW-A sediment sequences, paleoenvironmental changes were reconstructed since 2ka in Otindag sandland. Sandy soil with greater value of silt and clay content, magnetic susceptibility,and loss on ignition were developed in the episode of 1.45 ~1. lOka and 0. 83 -0. 58ka, while yellow sand layer with more coarse grain, less silt and clay and magnetic susceptibility as well as loss on ignition were developed at 1. 10 -0. 83ka and 0. 58 ~0. 20ka. The development of sandy soil represents wetter and wanner conditions, leading to the increase of vegetation coverage and much less aeolian activity. These phases were the warming periods of Tang Dynasty and the Yuan Dynasty in Chinese history correlating with the Medieval Warming Period in Europe. In that time, the ideal natural environment helped the great development of the

  6. 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.

  7. Recent developments of OSL techniques for dating quartz and feldspars

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Jungner, H.; Mejdahl, V.

    1993-01-01

    The construction of a unit for measuring optically stimulated luminescence from quartz and feldspar is described. The light sources used for stimulation are infrared diodes for feldspar and green light from a halogen lamp (obtained with a system of filters) for both quartz and feldspar. The unit ...

  8. 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 ne

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

    DEFF Research Database (Denmark)

    Guralnik, Benny; Jain, Mayank; Herman, Frédéric;

    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 ∼2 km of the Earth's crust. Here we introduce...... 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...... recent ambient temperatures of the shallow crust (200 °C Ma−1 range). Although Na-feldspar IRSL is prone to field saturation in colder or slower environments, the method's primary relevance appears to be for borehole and tunnel studies, where it may offer remarkably recent (...

  10. 毛乌素沙漠东南缘全新世剖面光释光年代及古气候意义%OSL DATING OF HOLOCENE SEQUENCE AND PALAEOCLIMATE CHANGE RECORD IN SOUTHEASTEARN MARGIN OF MU US DESERT,NORTH CHINA

    Institute of Scientific and Technical Information of China (English)

    马冀; 岳乐平; 杨利荣; 孙蕗; 徐永

    2011-01-01

    correspond to three considerable dune fixations. In order to establish reliable timing of dune development, this study applied optically stimulated luminescence ( OSL) dating techniques to the aeolian sediments features. 10 luminescence samples obtained from this profile were dated using the quartz single aliquot regeneration ( SAR) protocol. Combining with palaeoclimate proxies ( e. g. , grain sizes and magnetic susceptibilities) ,the records revealed as many as seven periods of significant rapid climate changes during the time intervals the palaeosoil layers deposited. The spatial and temporal extent of the data have allowed for correlations to be made with evidence from global climate changes. The first arid episode occurred before 7. 5ka in the early Holocene, with widespread aeolian sand mobilization and sparse vegetation. During 7. 5 ~ 3. 9ka , climate turned to be warmer and more humid with the occurrence of thick palaeosoil layers in the lowest, at the same time with Holocene Optimum.When it comes to 3. 9 ~ 2. 9ka .the dune rebounded to reactive with strong winter monsoon , and the climate became arid again. The timing of widespread dune reactivation coincided with well-known 4ka event. The climate became warm and humid during 2. 9 ~ 1. 7ka , with lower magnetic susceptibility than the upper palaeosoil layer. Although the summer monsoon is weakened. the winter monsoon failed to become predominant. Climate fluctuated more frequently after 1. 7ka with a warm climate episode during 1. 0 ~ 0. Ska and an arid one around 0. 2ka. It also revealed that the human significance of Holocene climate variability since 1ka ago. More importantly , the Holocene climate changes and evolution records from the Jinjie section could be correlated with the worldwide millennial-scale climate shifts , suggesting that the activity of East Asia monsoon in the Holocene may have directly been controlled or affected by global climate system. Several intervals coincide with major

  11. 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)

  12. Characterization of commercial MOSFETS electron dosimetry; Caracterizacion de MOSFETS comerciales para dosimetria con electrones

    Energy Technology Data Exchange (ETDEWEB)

    Carvajal, M. A.; Simancas, F.; Guirado, D.; Banqueri, J.; Vilches, M.; Lallena, A. M.; Palma, A. J.

    2011-07-01

    In recent years there have been commercial dosimetry devices based on transistors Metal-Oxide-Semiconductor (MOSFET) having a number of advantages over traditional systems for dosimetry in medical applications. These include the portability of the sensor element and a reading process quick and relatively simple dose, linearity, and so on. The use of electron beams is important in modern radiotherapy include its use in intra-operative radiotherapy (RIO). This paper presents an initial characterization of different business models MOSFET, not specific for radiation detection, to demonstrate their potential as sensors for electron beam dosimetry. (Author)

  13. 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).

  14. 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)

  15. Dosimetry in thorax X-rays; Dosimetria en radiografia de torax

    Energy Technology Data Exchange (ETDEWEB)

    Pinedo S, A.; Hernandez O, M.; Duran M, H. A.; Gonzalez G, R.; Guerra M, J. A.; Salas L, M. A.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98000 Zacatecas (Mexico); Rivera M, T. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)], e-mail: lare_56@hotmail.com

    2009-10-15

    The dose to the entrance of thorax during a radiological study has been measured in a phantom of paraffin and with thermoluminescent dosemeters. This work was realized in the living room 1 of the X-rays service of the General Hospital No. 1 IMSS in Zacatecas. For the study thermoluminescent dosemeters of CaSO{sub 4}:Dy were used. The irradiation of the thoracic region is the more studied through the conventional radiology, method that continues occupying the first place as diagnostic in diverse pathologies due to generates images of the heart, lungs, spine, etc. As well as can to observe the location of subclavian catheters, nasogastric sound, endotracheal tubes and umbilical catheters. The magnitude of the dose that is received during the realization of this study type is not usually measured, since the main concern is to have a good image to make a good diagnostic. The measurements were carried out using parameters of the equipment that were defined with base to the experience of the technical radiologist. It was found that the irradiation field is not uniform and that in any point where the dose was measured it is not exceeded the 7 mGy settled by the Mexican Official Standard-157-SSA-1996 for a thorax study. (author)

  16. Neutron spectrometry and dosimetry using NSDAAN; Espectrometria y dosimetria de neutrones usando NSDAAN

    Energy Technology Data Exchange (ETDEWEB)

    Martinez B, M. R.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Ortiz R, J. M. [Departamento de Electrotecnia y Electronica, Escuela Politecnica Superior, Av. Menendez Pidal s/n, 14004 Cordoba (Spain)], e-mail: mrosariomb@yahoo.com.mx

    2009-10-15

    The reconstruction of neutron spectra from count rates of a Bonner spheres spectrometric system is performed using various methods such as Monte Carlo methods, the parameterization and iterative methods. The weight of the Bonner spheres spectrometric system, the procedure for the reconstruction of the spectra, the need of an experienced user, the high consumer of time, the need of use a reconstruction code as the BUNKI, SAND, among others, and the resolution of the spectrum are some problems that this system presents. This has motivated the development of complementary procedures such as maximum entropy, genetic algorithms and artificial neural networks. In previous work, has reported 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, due to the newness of this technology, be noted that there are not tools to end-user that allow test and validate the designed networks. This paper presents a software for the neutron spectrometry and dosimetry, designed from the information extracted of an artificial neural network designed by robust design methodology of artificial neural networks. This tool has the following characteristics: was designed in a user graphical interface easy to use, requires not knowledge of neural networks or neutron spectrometry by the user; execution speed of the application; unlike the deconvolution codes are not required to select an initial spectrum for the spectrum reconstruction; as an additional element to this tool, besides the spectrum, the calculation is performed simultaneous to H(10), E, H{sub p},{sub s}(10,{theta}) from just counting rates from a Bonner spheres spectrometric system. (author)

  17. 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)

  18. 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)

  19. 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.

  20. 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)

  1. 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.

  2. 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)

  3. 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)

  4. 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.

  5. Tridimensional dosimetry using MAGIC gel with formaldehyde; Dosimetria tridimensional usando gel MAGIC com formaldeido

    Energy Technology Data Exchange (ETDEWEB)

    Pavoni, Juliana F.; Baffa, Oswaldo [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica e Matematica], e-mail: baffa@ffclrp.usp.br; Pike, Tina L.; Snow, Jessica; DeWerd, Larry A. [University of Wisconsin, Madison, WI (United States). Dept. of Physics. Medical Radiation Research Center

    2010-03-15

    This paper presents the application of MAGIC gel with formaldehyde (MAGIC-f) in the tri dimensional dose distribution measurement of an IMRT planning. A high similarity was found between the dose distributions measured by the gel dosimeter and the dose distributions expected by the treatment planning system (TPS) in all of the irradiated volume, this was proved by the direct overlapping of these isodoses. These results show that MAGIC-f gel is feasible for tridimensional dose distribution measurements. (author)

  6. Biological dosimetry in radiological emergency; Dosimetria biologica en situacion de emergencia radiologica

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)], e-mail: citlali.guerrero@inin.gob.mx

    2009-10-15

    When accidents occur where large numbers of people are exposed to high doses of ionizing radiation is necessary to take urgent decisions regarding the appropriate treatment that is required. In this regard, chromosome analysis can provide additional information to that obtained from clinical observations confirming cases that had serious partial exposure and discriminating at same time to the false positives attributable to previous infections or to hysterical behaviour. Ionizing radiation causes various types of aberrations in chromosomes but one of the most characteristics is the dicentric. The analysis of these in lymphocytes is a good indicator of level exposure, in addition to be of easy examination, the basal frequency on the population is low (1 x 10{sup 3} cells) and increases in proportion to dose. To set the exposure dose is usually required to analyze 1000 cells, a procedure that in emergencies is very slow because it requires quick decisions to apply the adequate treatment to patient. For that reason when occurred the nuclear accident in Chernobyl, was established a criterion of quick analysis test based on examination of 50 metaphases for each case. To corroborate the validity of an alternative criterion (50 metaphases or 30 dicentrics), later in year 2000 was simulated in laboratory one accident exposing peripheral blood lymphocytes in whole or in part within a range of 0-8 Gy of gamma radiation. As part of activities of Regional Project IAEA - RLA/9/054 (strengthening of national systems for preparedness and response in radiological and nuclear emergencies) the seven participating countries made and inter calibration exercise for the dicentrics analysis and corresponding dose estimated, parallel, decided to estimate the dose from analysis of 25, 50, 100 or 500 metaphases and thus sets the minimum number that should be examined for reliable results. The results of inter calibration exercise agree with those previously published in 2000, indicate that the analysis of 50 metaphases, regardless of the dicentrics number there is enough to separate the overexposure cases of non radio exposed, and the first results placed in a dose category. (Author)

  7. Dosimetry of hands and human factor; Dosimetria de manos y factor humano

    Energy Technology Data Exchange (ETDEWEB)

    Harr, R. [Sociedad Mexicana de Seguridad Radiologica A. C., Mexico D. F. (Mexico)

    2008-12-15

    The human factor in facilities where open radioactive sources are managed it can be controlled through the use of the ring dosimetry, however, that these devices only provide qualitative information that is not extrapolated to legislative limits. lt is present the case analysis of hands dosimetry of female person with responsibility for professional standards and a very high profile with ratings that allow her to have a high level of knowledge of the basic standards, and because with an attitude and a culture rooted of radiation protection, among other qualities. Their records reveal a trend in which monthly doses are below the 7 mSv, and only occasionally are between 7 and 12 mSv per month and hand. The other case correspond to a technician, trained in radiological techniques, also with a high profile, with two courses for occupationally exposed personnel more than 10 annual retraining, and work experience of over 10 years as occupationally exposed personnel, in which knowledge of standards and because of the entrenched culture of radiation protection and their interest degree in the care of their exposure is still in a phase half, in this case also shows a trend in the monthly dose where found registers between 7 and 11 mSv per month and hand. The third case is of a second technician with less experience and most basic knowledge, his dose register not show a real trend, sometimes be found reads of irregular values as if the dosimeter is not used and some other times as if misused by exposing to purpose (was observed at least one reading above the monthly 30 mSv). By way of conclusion, it is noted that the hands dosimetry is a useful tool to monitor transactions through the data compilation susceptible to analysis with variations which can be placed in the context of the human factor. (Author)

  8. 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)

  9. 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)

  10. 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)

  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. 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)

  13. 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.

  14. 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...

  15. Cat Island Terrestrial Core Optically Stimulated Luminescence (OSL) Data from field activity 10BIM03

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center (SPCMSC), in collaboration with the U.S. Army Corps of Engineers...

  16. Cat Island Terrestrial Core Optically Stimulated Luminescence (OSL) Data from field activity 10BIM03

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center (SPCMSC), in collaboration with the U.S. Army Corps of Engineers...

  17. 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...

  18. 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

    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...... 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...... 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...

  19. Development of an OSL chronology for Late Pleistocene channel belts in the lower Mississippi valley, USA

    Science.gov (United States)

    Rittenour, Tammy M.; Goble, Ronald J.; Blum, Michael D.

    2005-12-01

    The broad alluvial valley of the lower Mississippi River contains large channel belts for which age control has been limited by the lack of organic material for radiocarbon dating and deposit ages greater than the limit of radiocarbon. In order to produce a detailed chronology of fluvial evolution, samples for optical dating were collected from Late Pleistocene channel-belt deposits. Quartz sand was analyzed using the coarse-grained, single-aliquot regenerative-dose (SAR) technique. Samples showed little evidence of partial bleaching, and optical ages are for the most part consistent with the available radiocarbon and relative age constraints. Optical ages range from 85 to 11 ka and, along with geomorphic and stratigraphic relationships, indicate that the Mississippi River was meandering during the end of the last interglacial (85-83 ka) and switched to a braided regime by 64-50 ka during initial marine oxygen isotope stage (OIS) 4/3 glaciation of the upper Mississippi drainage basin. The Mississippi River switched back to a meandering regime after formation of the youngest braid belt at 11 ka. The 69 optical ages presented here provide the first detailed chronology of lower Mississippi valley braid-belt and Pleistocene meander-belt formation, and provide an example of the utility of optical dating in fluvial settings where material for radiocarbon dating is scarce.

  20. 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...

  1. 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

    Luminescence chronology may be the key to understanding climatically and tectonically driven changes on Mars. However, the success of Martian luminescence dating will depend upon our understanding of the luminescence properties of silicates such as olivine, pyroxenes and plagioclases, and sedimen......), and the effect of radiation damage due to cosmic ray exposure are presented and implications discussed for Martian luminescence dating. (c) 2006 Elsevier Ltd. All rights reserved.......Luminescence chronology may be the key to understanding climatically and tectonically driven changes on Mars. However, the success of Martian luminescence dating will depend upon our understanding of the luminescence properties of silicates such as olivine, pyroxenes and plagioclases......-aerial transport; this may allow possibility of using deep traps for extending the age range on Mars. Dose rates on Mars are largely due to charged particles present in the galactic cosmic rays. Some new results on proton dosimetry with Al2O3:C (Bragg curve and luminescence efficiency as a function of LET...

  2. OSL dating of mixed coastal sediment (Sylt, German Bight, North Sea)

    DEFF Research Database (Denmark)

    Reimann, Tony; Lindhorst, Sebastian; Thomsen, Kristina Jørkov;

    2012-01-01

    and aeolian sediments because of the sampling method employed. To obtain reliable burial ages for these swash-bar sediments, single-grain and small aliquot measurements were used together with the Finite Mixture Model (FMM) proposed by Roberts et al. (2000) to identify the grain population containing...... the largest doses (from the deepest part of the core). Before the FMM was applied to dating, the parameters and performance of the FMM were first investigated by systematically comparing small aliquot (∼20 grains) and single-grain measurements of an undisturbed aeolian and swash-bar sample and a laboratory...... aliquots can be regarded as a reliable proxy for single-grain dose distribution if the sediment contains only a small proportion of quartz grains emitting a luminescence signal and that the FMM results are relatively insensitive to changes of the over-dispersion parameter between 5–40% for small aliquots...

  3. 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)

  4. 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)

  5. 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)

  6. Dosimetric study in iodine-125 seeds for brachytherapy application; Dosimetria de fontes de iodo-125 aplicadas em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Zeituni, Carlos Alberto

    2008-07-01

    The demand for iodine-125 seeds for use in brachytherapy treatments has experienced an increase along recent years in Brazil and all over the world. All iodine-125 seed must have its operational parameters measured and/or calculated every time changes in the production process are carried out. A complete dosimetric measurement is very expensive, and it is recommended that this procedure must be repeated at least once a year. Thus, this work developed a methodology for the entire dosimetric process. This methodology is based on the scarce information available in the literature, once almost all the methodology used in large industrial laboratories is commercial secret. The proposed methodology was tested using seeds of Amersham-Oncura-Ge Healthcare, which is the largest seed manufactory in the world. In this new methodology, an automatic reader was employed in order to reduce the time required in the selection process of the TLD-100 dosimeters used and a postprocessing of the obtained spectra was carried out. A total of 142 dosimeters were used and only 29 have been selected using the new methodology. Measurements were performed using slabs of Solid Water RW1 to simulate measuring in the 'water', using three different experimental apparatus and each measurement was repeated at least three times. The TLD-100 calibration was performed using a Dermopan II - Siemens. The measured values showed a good agreement with the ones available in the literature. Finally, these measured values were compared with calculated ones obtained by a semiempirical simulation program, showing a good agreement and, therefore, demonstrating the validity of the proposed methodology regarding dosimetric calculations. (author)

  7. 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)

  8. 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)

  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. Cytogenetic dosimetry intercomparison among four Latin American countries; Intercomparacao em dosimetria citogenetica entre quatro paises latino-americanos

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)]. E-mail: adriana@ird.gov.br; Nasazzi, Nora; Giorgio, Marina Di; Taja, Maria Rosa [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina)]. E-mail: nnasazzi@cae.arn.gov.ar; Garcia, Omar F.; Lamadrid, Ana I. [Centro de Proteccion e Higiene de las Radiaciones, La Habana (Cuba)]. E-mail: omar@cprh.edu.cu; Lopez, Ines [Comision Chilena de Energia Nuclear (CCHEN), Santiago (Chile)]. E-mail: ilopez@gopher.cchen.cl

    2001-07-01

    Cytogenetic dosimetry is the most powerful biological tool for dose assessment in cases of radiological accidents and suspected overexposures. In Latin America, the use of this technique is concentrated in a few countries. An intercomparison exercise in biological dosimetry was performed. It aimed to check if the laboratories would score similar frequencies of unstable chromosomal aberrations in an irradiated blood sample. The interlaboratory differences in the scored yields of aberrations are within expected limits for this technique. It was observed the presence of a few rogue cells. Those cells show an extreme level of chromosomal damage. The observations thus departed grossly from a Poisson distribution. (author)

  11. Dosimetry in a torso phantom during a mammography; Dosimetria en un fantoma de torso durante una mastografia

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez O, M.; Duran M, H. A. [Universidad de Sonora, Blvd. Luis Encinas y Rosales s/n, Hermosillo 93000, Sonora (Mexico); Pinedo S, A.; Salas L, M. A.; Hernandez D, V. M.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Rivera M, T. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Ventura M, J. [Hospital General de Zona No. 1, IMSS, Interior Alameda 45, 98000 Zacatecas (Mexico)

    2009-10-15

    Two dosimetric magnitudes, the absorbed dose and the kerma in air to the entrance of torso have been determined. These dosimetric magnitudes are due to the radiation that is dispersed in the mammary gland when the patient undergoes a mammography study. The kerma to the entrance of the torso and the absorbed dose by the torso was obtained in a phantom of paraffin and with thermoluminescent dosemeters of ZrO{sub 2}. The dosemeters were placed on the surface of the torso phantom while the mammography was carried out. (author)

  12. Dosimetry in CT with TLD and ionization chambers; Dosimetria em TC com TLD e camaras de ionizacao

    Energy Technology Data Exchange (ETDEWEB)

    Terini, Ricardo A.; Nerssissian, Denise Y.; Campelo, Maria Carolina S.; Yoshimura, Elisabeth M., E-mail: rterini@if.usp.br [Universidade de Sao (USP), Sao Paulo, SP (Brazil). Lab. de Dosimetria das Radiacoes e Fisica Medica

    2016-07-01

    In modern Computed Tomography (CT), CTDI{sub 100} measurements often underestimate accumulated dose on the gantry center. The AAPM TG 111 report proposed improved metrics for CT dosimetry, mainly for helical and wide beam width scanning. In this study, a properly calibrated small 0.6 cc (0.6-L) ion chamber was used as reference to characterize RQT standard beams at the IF-USP Dosimetry Lab. Similarly, two CT pencil chambers (3CT-V and 3CT-L) and another 0.6 cc chamber (0.6-V) undergone cross calibration in the same beams and were subsequently applied to CTDI measurements in a clinical CT. Doses with TLDs were also acquired in this equipment, as well as in the lab, and calibration curves were plotted against the measurements obtained with the 0.6-V ion chamber. Results have shown differences up to 15% in CTDI values measured by both chambers. For 110 and 130 kV, TL readings have shown variations up to 1%. (author)

  13. 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)

  14. 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)

  15. Quality control and dosimetry in computed tomography units; Controle de qualidade e dosimetria em equipamentos de tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Pina, Diana Rodrigues de; Ribeiro, Sergio Marrone [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina], e-mail: drpina@fmb.unesp.br; Duarte, Sergio Barbosa [Centro Brasileiro e Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Netto, Thomaz Ghilardi [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas. Centro de Ciencias das Imagens e Fisica Medica; Morceli, Jose [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Secao de Diagnostico por Imagem; Carbi, Eros Duarte Ortigoso; Costa Neto, Andre; Souza, Rafael Toledo Fernandes de [UNESP, Botucatu, SP (Brazil). Inst. de Biociencias

    2009-05-15

    Objective: Evaluation of equipment conditions and dosimetry in computed tomography services utilizing protocols for head, abdomen, and lumbar spine in adult patients (in three different units) and pediatric patients up to 18 months of age (in one of the units evaluated). Materials and methods: Computed tomography dose index and multiple-scan average dose were estimated in studies of adult patients with three different units. Additionally, entrance surface doses as well as absorbed dose were estimated in head studies for both adult and pediatric patients in a single computed tomography unit. Results: Mechanical quality control tests were performed, demonstrating that computed tomography units comply with the equipment-use specifications established by the current standards. Dosimetry results have demonstrated that the multiplescan average dose values were in excess of up to 109.0% the reference levels, presenting considerable variation amongst the computed tomography units evaluated in the present study. Absorbed doses obtained with pediatric protocols are lower than those with adult patients, presenting a reduction of up to 51.0% in the thyroid gland. Conclusion: The present study has analyzed the operational conditions of three computed tomography units, establishing which parameters should be set for the deployment of a quality control program in the institutions where this study was developed. (author)

  16. 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)

  17. 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.

  18. Gamma radiation processing dosimetry with commercial silicon diodes; Dosimetria de processos de irradiacao gama com diodos comerciais de silicio

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Danilo Cardenuto

    2009-07-01

    This work envisages the development of dosimeters based on Si diodes for gamma radiation dosimetry from 1 Gy up to 100 Gy. This dose range is frequently utilized in radiation processing of crystal modifications, polymers crosslinking and biological studies carried out in the Radiation Technology Center at IPEN-CNEN/SP. The dosimeter was constructed by a commercial SFH00206 (Siemens) Si diode, operating in a photovoltaic mode, whose electrical characteristics are suitable for this application. The current generated in the device by the Cobalt-60 gamma radiation from the Irradiators types I and II was registered with a digital electrometer and stored during the exposure time. In all measurements, the current signals of the diode registered as a function of the exposure time were very stable. Furthermore, the device photocurrent was linearly dependent on the dose rate within a range of 6.1x10{sup -2} Gy/min up to 1.9x10{sup 2} Gy/min. The calibration curves of the dosimeters, e.g., the average charge registered as a function of the absorbed dose were obtained by the integration of the current signals as a function of the exposure time. The results showed a linear response of the dosimeter with a correlation coefficient better than 0.998 for total absorbed dose up to 120 Gy. Finally, due to the small experimental errors 5 % it was also possible to measure the transit dose due to the movement of the Cobalto- 60 radioactive sources in irradiation facilities used in this work. (author)

  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. Safety study of a radioactive facility with TLD dosimetry; Estudio de seguridad de una instalacion radiactiva con dosimetria TLD

    Energy Technology Data Exchange (ETDEWEB)

    Diez Villafanez, M.; Benavente Ruiz, M. A.; Ruiz Penalba, F. J.; Enriquez Payan, F.; Sotelo Garcia, O.; Rey Martinez, M.; Pardos Ibanez, R.

    2011-07-01

    The project purpose is to confirm experimentally the radiation safety using the technique of thermoluminescence dosimetry (TLD), using the reference desk study carried out for gamma irradiation room in the Safety Study was authorized by the radioactive facility.

  1. Internal dosimetry for occupationally exposed personnel in nuclear medicine; Dosimetria interna para personal ocupacionalmente expuesto en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.T.; Alfaro, L.M.M.; Angeles, C.A., E-mail: teodoro.garcia@inin.gob.mx, E-mail: mercedes.alfaro@inin.gob.mx, E-mail: arturo.angeles@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares Carrelera Mexico-Toluca, Ocoyoacac, MX (Mexico)

    2013-10-01

    Internal dosimetry plays an important role in nuclear medicine dosimetry control of personnel occupationally exposed, and that in recent years there has been a large increase in the use of radionuclides both in medical diagnosis as radiotherapy. But currently, in Mexico and in many parts of the world, this internal dosimetry control is not performed. The Instituto Nacional de lnvestigaciones Nucleares de Mexico (ININ) together with the Centro Oncologico de Toluca (ISEMMYM) have developed a simple and feasible methodology for monitoring of personnel working in these facilities. It was aimed to carry out the dosimetry of the personnel, due to the incorporation of I-131, using the spectrometric devices that the hospital has, a gamma camera. The first step in this methodology was to make a thyroid phantom to meet the specifications of the ninth ANSI. This phantom is compared under controlled conditions with RMC- II phantom used for system calibration of the ININ internal dosimetry (ACCUSCAN - Ll), and with another phantom developed in Brazil with ANSI specifications, in order to determine the variations in measurements due to the density of the material of each of the phantoms and adjust to the system ACCUSCAN, already certificate. Furthermore, necessary counts were performed with the gamma camera of the phantom developed at ININ, with a standard source of {sup 133}Ba which simulates the energy of {sup 131}I. With these data, were determined the counting efficiencies for a distance of 15 to 20 cm between the surface of the phantom and the the plate of the detectors. Another important aspect was to determine the lower limit of detection (LLD). In this paper we present the results obtained from the detectors calibration of the gamma camera of the hospital.

  2. 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

  3. 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.

  4. 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)

  5. 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)

  6. 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)

  7. Manufacture of polystyrene phantoms for beta radiation dosimetry; Confeccao de objetos simuladores em poliestireno para dosimetria da radiacao beta

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcia L.; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: mlolivei@ipen.br; lcaldas@ipen.br

    2005-07-01

    {sup 90}Sr+{sup 90}Y beta radiation sources should be specified in terms of absorbed dose rate to water, following recent international recommendations. Due to the high dose gradients near source surfaces, the accurate determination of the distances involved in calibration procedures is extremely important, since the calibration of these sources is performed at 1 mm from their surfaces, in their central symmetry axis. To guarantee the adequate and reproducible positioning between the source during the calibration procedure and the radiation detector, the use of solid phantoms is convenient. Recent papers show that the most appropriate material as water substitute for beta radiation is the polystyrene. In this work, polystyrene phantoms were manufactured for thermoluminescent samples of LiF, CaF{sub 2}:Dy and CaF{sub 2}:Mn. A {sup 90}Sr+{sup 90}Y plane applicator was utilized to irradiate the samples. The maximum sample response variation was equal to: 4.9% for LiF; 3.7% for CaF{sub 2}:Dy; and 3.3% for CaF{sub 2}:Mn. The obtained results show the feasibility of the use of polystyrene phantoms in beta radiation dosimetry. The low cost phantoms guaranteed the reproducible positioning between the {sup 90}Sr+{sup 90}Y source and the samples, as desired. (author)

  8. 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)

  9. Development of polyaniline thin films for gamma radiation dosimetry; Desenvolvimento de filmes finos de polianilina para dosimetria da radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Ana Paula; Araujo, Elmo S. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear; Azevedo, Walter M. de [Pernambuco Univ., Recife, PE (Brazil). Dept. de Quimica Fundamental

    2001-07-01

    The increasing applications of the ionizing radiation added to the difficulty on operation of some dosimeters have became necessary the development of news materials and news dosimetry techniques. On the other hand, the study of the properties of conducts polymers are quite recent as well as its research in the dosimetry field is still superficial. The utilization of polyaniline (PANI) as a dosimetric material is of great relevancy, because this polymer has got good quality in the dosimetry. It is easy to operation, the devices may be fabricated in different geometry, it is a low cost material, and the electrical properties variation measurement system is simple. In addition, it does not exist previously study that characterizes this polymer as a dosimeter. Some early results have showed that doped PANI when irradiated with gamma rays ({sup 60} Co), dose range from 0 to 10kGy, responds proportionally to the doses above 1kGy. Thus, it is possible the utilization this polymer in high-energy dosimetry. Studies much more detailed are being made in order to complete the evidence of PANI as a dosimetric material. (author)

  10. 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)

  11. 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.

  12. 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)

  13. 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)

  14. 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)

  15. 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)

  16. 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)

  17. 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)

  18. 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)

  19. Building on previous OSL dating techniques for gypsum: a case study from Salt Basin playa, New Mexico and Texas

    Science.gov (United States)

    Mahan, Shannon; Kay, John

    2012-01-01

    The long term stability and reliability of the luminescence signal for gypsum has not been well documented or systematically measured until just recently. A review of the current literature for luminescence dating of gypsum is compiled here along with original efforts at dating an intact and in-situ bed of selenite gypsum at Salt Basin Playa, New Mexico and Texas. This effort differs from other documented luminescence dating efforts because the gypsum is not powdery or redistributed from its original growth patterns within the playa basin but is instead of a crystalline form. Sixteen ages from eight cores were ultimately produced with seven of the ages coming from rare detrital quartz encased in or with the gypsum crystals while the remaining ages are from the crystalline gypsum. As far as can be ascertained, the quartz was measured separately from the gypsum and no contaminants were noted in any of the aliquots. Some basic and preliminary tests of signal stability were measured and found to be mitigated by lessening of pre-heat protocols. Ages ranged from 8 ka to 10 ka in the shallow cores and 16 ka to 22 ka in the deeper cores. These ages will be useful in determining rates of gypsum growth within a sequence of evaporates which, in turn, will help to better document historic rates of evaporation and thus estimate, with more precision, the corresponding annual evaporation rates.

  20. 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...

  1. 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

    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....

  2. 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.

  3. 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)

  4. 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.

  5. 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...

  6. Evaluation of personal dosimetry in abdominal aorta endo prosthesis procedures; Avaliacao da dosimetria pessoal em procedimentos de endoproteses de aorta abdominal

    Energy Technology Data Exchange (ETDEWEB)

    Bacchim Neto, Fernando A.; Alves, Allan F.F.; Freitas, Carlos C.M. de; Pina, Diana R. [Universidade Estadual Paulista Julio de Mesquita Filho (FMB/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina

    2016-07-01

    The objective of this paper is to evaluate the currently dosimetry technique employed in the medical staff during interventional radiology procedures. Thermoluminescent dosimeters were positioned in different regions of the primary interventionist during procedures of stent graft in abdominal aortic aneurysms. The equivalent dose rate profile shows a tendency of difference between dose rate found in the chest in relation to the abdomen, hands and feet. Statistically, dose rates found in the hands differ from those found in the chest with p=0.05. These results suggest that only a dosimeter placed on the chest does not describe faithfully the radiation doses to which these professionals are occupationally exposed. (author)

  7. 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)

  8. Dosimetry of electromagnetic fields for compliance of radiological safety standards; Dosimetria de campos electromagneticos para el cumplimiento de normativas de seguridad radiologica

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, M.

    2005-07-01

    The non-ionizing radiation in occupational, public or residential environments shows a wide variety of characteristics regarding its frequency, power, time pattern, orientation, etc. For a correct dosimetry, it is necessary to choose among diverse measurements protocols and equipment: broadband equipment, selective meters, isotropic probes, high frequency, low frequency, personal monitors, area monitors...How should they be chosen? It depends on the more information available, the easier it will be to take the right decision. For this purpose, it is necessary to understand the physics of the electromagnetic fields (electric field, magnetic field, far and near field) and to be familiar with the corresponding safety limits (occupational or public exposure) in each case. Besides, it is very important to understand the differences between the different technologies used in the modern instrumentation and their applications to specific situations. (Author)

  9. 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)

  10. 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)

  11. 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)

  12. 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)

  13. 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)

  14. Radon dosimetry occupational safety in working area of Sanpaolo IMI organization; Individuazione e dosimetria del radon presso i presidi operativi del gruppo Sanpaolo IMI: parte 1

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Giuseppe; Bresciani, Sara [ASO Ordine Mauriziano, Torino (Italy); Coggiola, Maurizio [Torino Univ., Torino (Italy). DTP Traumatologia, ortopedia e medicina del lavoro; Magnone, Maurizio; Chiaberto, Enrico [Arpa Piemonte, Torino (Italy)

    2005-05-15

    The Radon 222 is a natural radioactive gas present inside rocks, soil and building materials. Its decay produce ionizing Alpha radiation. The OMS Organization classified the Radon as cancerogenic substance of group 1 at most high cancerogenicity. In Italy the Radon risk is regulated in law 230 and its modifications.

  15. 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)

  16. 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)

  17. 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)

  18. 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)

  19. 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)

  20. 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)

  1. Radiation monitoring in facilities of PET-CT thermoluminescence dosimetry; Vigilancia radiologica en instalaciones de PET-TC con dosimetria de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Casa de Julian, M. A. de la; Gilarranz Moreno, R.; Martinez Gomez, L. C.; Clemente Gutierrez, F.; Manzanas Artigas, M. J.

    2011-07-01

    The PET-CT is a powerful diagnostic tool of relatively recent introduction, Following the opening of two PET-CT facilities, the CSN requested to do radiological monitoring of both facilities for a year to check the shields. These shields were calculated according the formalism proposed in the AAPM TG 108 of the. Here we review data from radiation monitoring.

  2. Magnitudes and units in the X-ray dosimetry in diagnostic radiology; Magnitudes y unidades en la dosimetria de rayos-X en radiologia diagnostica

    Energy Technology Data Exchange (ETDEWEB)

    Tovar M, V. M.; Cejudo A, J.; Vergara M, F. [Departamento de Metrologia de Radiaciones Ionizantes, ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)], e-mail: victor.tovar@inin.gob.mx

    2009-10-15

    The dosimetry objective in the radiological image is the quantification from the exposition to the radiation with a commitment of optimizing the image quality to the reason of the absorbed dose. The dosimetry has the meaning of avoiding excessive dose that could imply a significant risk of deterministic effects induction. The dosimetric magnitudes and dosimetry protocols in the radiological image, are those that are related to the risks for the patient. Exist in diagnostic radiology two fundamentals reason to measure or to estimate the patient radiation dose. First, the mensurations are a means to verify the good practices and an aid to the optimization of the patient protection. Second, the absorbed dose estimation to tissues and organs in the patient are necessary to determine the risks, and this way to indicate that the radiological techniques employees can be justified and in investigated cases of over exposition. (Author)

  3. Neutron dosimetry: problems, solutions, prospects and the role of trace detectors; Dosimetria neutronica: problemas, soluciones, perspectivas y el papel de los detectores de traza

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, F. [Consejo de Seguridad Nuclear, Justo Dorado 11, 28040 Madrid (Spain)

    2009-10-15

    It is present in schematic way, the origin of the neutrons; their interaction with matter, until its application in the field of dosimetry. It describes some measuring instruments based on thermoluminescence dosimetry, some activation detectors and trace detectors. Finally, it summarizes the work in neutron dosimetry have been carried out at the Autonomous University of Barcelona. (Author)

  4. 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)

  5. 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)

  6. 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)

  7. 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)

  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 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)

  10. Characterization of thermoluminescent crystals (LIF:MG.TI) for dosimetry in patients of radiotherapy; Caracterizacion de cristales termoluminiscentes (LIF:MG.TI) para dosimetria de pacientes de radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Valderrama, Z.; Machado, H.; Plazas, M.

    2006-07-01

    The dosimetry allows us to verify the dose received by a patients, detecting a possible sub or over dosage at the beginning of the Radiation treatment or during the course of it. In such a way, those corrections can be made on subsequent fractions. This contributes to the evaluation of uncertainties on the planning and delivery of dose to the target volume and organs at risk. At the same time, it allows to detect possible abnormalities on the operation of radiation emitting equipment. The purpose of this work is to show the viability of a quality assurance routine using a TLD system. To reach to goal, TLD detectors response characteristics were determined by means of a cobalt 60 beam. (Author)

  11. Dosimetry in dental radiology. Dentascan spiral CT versus panoramic radiography; Dosimetria nella radiologia odontostomatologica: confronto tra tomografia computerizzata spirale e ortopantomografia

    Energy Technology Data Exchange (ETDEWEB)

    Villari, N.; Stecco, A.; Zatelli, G. [Florence Univ., Florence (Italy). Dipt. di fisiopatologia clinica

    1999-05-01

    The study compares the doses absorbed by the dentomaxillary area in spiral CT and panoramic examinations. The dose measurements demonstrate that patients receive smaller doses with panoramic radiography than with spiral CT with Dentascan. After following for some variations from instrumental differences, they are in substantial agreement with literature data. Further investigations are needed considering the radiobiological risk related to the growing spread of Dentascan examinations. [Italian] Questo lavoro intende confrontare le dosi assorbite nel distretto dento-mascellare, con le due principali tecniche utilizzate in questo campo: TC spirale e ortopantomografia. Emerge come l'esame panoramico delle arcate dentarie eseguito con l'ortopantomografo comporti la'ssorbimento di dosi inferiori rispetto a quelle dell'esame TC spirale con programma Dentascan. Questi dati, pur essendo soggetti a variabilita' dovuta alla strumentazione utilizzata, sono paragonabili a quelli di altri studi e impongono ulteriori approfondimenti dato il crescente ricorso degli implantologi alla TC spirale con programma di ricostruzione Dentascan.

  12. 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.

  13. 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)

  14. 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.

  15. Metrological legal frame in the field of the photon dosimetry of radiotherapy in Cuba; Marco metrologico legal en el campo de la dosimetria fotonica de radioterapia en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Walwyn S, G.; Gutierrez L, S.; Gonzalez R, N. [CPHR, Calle 20 No. 4113 e/41 y 47, Playa C.P. 11300, La Habana (Cuba)]. e-mail: gonzalo@cphr.edu.cu

    2006-07-01

    The Clinical Dosimetry in the planning of the doses to administer to patients under radiant treatment is of great importance. At the moment the clinical dosemeters its are manufactured with a high technology but errors of production or manipulation cannot be discarded that lead to errors in this planning. It also exists, a group of metrological and of operation parameters that are not checked in a routine calibration, and for those that are checked, legal base that restricts its use in cases of bad operation doesn't exist. This motivated to the Cuban standard elaboration NC 352:2005, for the verification of reference dosemeters of radiotherapy, process that trafficked for an exhaustive search and study of standards and international technical reports, selecting as base document, the standard IEC 60731:1997, for essays of approval of model of clinical dosemeters used in radiotherapy. The present article shows the main technical aspects considered and the requirements and verification methods for the declaration of aptitude of the dosemeters. This document constitutes the scientific base for the implementation from a verification service to national level and an important contribution to the standardization of the metrology of ionizing radiations of Cuba. (Author)

  16. Application of numerical analysis in personal dosimetry by thermoluminescent; Aplicacion de metodos de analisis numerico en un sistema de dosimetria personal por termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Ros, J. M.; Delgado, A.; Fantuzzi, E.

    2003-07-01

    The main features of the methods for computerised glow curve analysis are presented in this communication together with a description of their advantages for TLD in replacement of standard procedures. A protocol for the employment of different kinds of computerised methods for personal dosimetry is proposed. The new results now presented demonstrate the possibility, using a very simple computerised analysis, of working with LiF GR-200 without any pre-heat or annealing simplifying the working procedures, now reduced to the simplest possible: a single step readout up to 240 degree celsius. (Author) 7 refs.

  17. Dosimetry of beta particles using Li:Mg, Cu, P + Ptfe; Dosimetria de particulas beta usando Li: Mg, Cu, P + Ptfe

    Energy Technology Data Exchange (ETDEWEB)

    Olvera, L.; Azorin, J.; Rivera, T. [Depto. de Fisica, UAM-I, 09340 Mexico D.F. (Mexico)

    2003-07-01

    This paper presents the experimental results of determining the thermoluminescence (Tl) response of LiF: Mg, Cu, P + Ptfe pellets excited with {sup 90}Sr/{sup 90}Y beta radiation. The glow curve exhibited three peaks which appear at 121 C, 178 C and 217 C . Its relative sensitivity is 49 with respect to that of the TLD-100 dosemeter taken as a reference. The minimal dose that could be measured was 750 mGy. The Tl response as a function of dose was linear in the range of 0.7 mGy to 22.5 mGy. The study of the repeatability of the information contained in the pellets showed a standard deviation of 2 %. (Author)

  18. 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)

  19. 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)

  20. 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)

  1. 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)

  2. 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)

  3. 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.

  4. 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)

  5. 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)

  6. 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)

  7. Development of ionizing radiations dosimetry by plastic detectors and films of radiography; Desenvolvimento de dosimetria de radiacoes ionizantes por detectores plasticos e filmes de radiografia

    Energy Technology Data Exchange (ETDEWEB)

    Levit, Vladimir; Santos, Ari S.; Louzada, Ana R.; Silveira, Cristina M.; Vaniel, Ana P. [Pelotas Univ., RS (Brazil). Inst. de Quimica e Geociencias]. E-mail: vlevit@ufpel.tche.br; Fedorov, Dmitri [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)]. E-mail: fedorov@nucleo.inpe.br

    2000-07-01

    This work shows the development of an automatic and computerized system for detection and analysis of the ionizing radiation trace in solid detectors and one of the signals of this irradiation in radiography films with the main goal of improve the ionizing radiation detection methods. On the development of this method it was used a calibration source of {sup 252}Cf, which is a radionuclide with alpha decay and spontaneous fission and, by this reason, irradiates {alpha} and {gamma} particles and nuclear fragments. Solid detectors of makrofol ware used for the nuclear fragments and radiography films ware used for the detection of {alpha} and {gamma} particles. Those signals images reveled of the {alpha} and {gamma} particles and of the nuclear fragments traces ware analysed on a microscopy and recorded on computers. The computer system developed allows to capture those images from the microscope as computer files, the identification of nuclear fragments traces and the {alpha} and {gamma} particles signals and the separation of the objects of interest to do the counting and analysis of the size and the shape of those traces.

  8. 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.

  9. 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)

  10. Dosimetria interna de radiofármacos derivados de polipeptídeos antitumorais isolados dos venenos de: Crotalus durissus terrificus e Scorpaena plumieri

    OpenAIRE

    Henrique Martins de Andrade

    2009-01-01

    A identificação de novos agentes terapêuticos e diagnósticos capazes de inibir o crescimento tumoral é essencial para melhoria no prognóstico de pacientes acometidos por tumores malignos (glioma, mama dentre outros). Nesse contexto, produtos naturais (vegetais e animais) constituem-se numa rica fonte de substâncias com potencial antitumoral. Polipeptídeos isolados dos venenos da serpente Crotalus durissus terrificus (Crtx) e do peixe Scorpaena plumieri (SPGP), apresentam atividade...

  11. 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)

  12. 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)

  13. Laboratory of research for environmental radiation and its dosimetry in the ININ; Laboratorio de investigacion de radiacion ambiental y su dosimetria en el ININ

    Energy Technology Data Exchange (ETDEWEB)

    Chavez S, B.M

    2003-07-01

    The objectives of this work are to learn on the methodology that should be continued for the investigation of such a specialized topic as it is a radiation laboratory and to develop the executive project of a building that contains laboratories focused to the investigation of the radiation levels in the environment and their dosimetry. The National Institute of Nuclear Research (ININ), is the place where are carried out many of the investigations related to the field of the physics and chemistry in Mexico besides being the center of nuclear research more important of Latin America and it is for that reason that here is proposed the Laboratory of Low Radiation and its Dosimetry, since the Institute accounts with the whole infrastructure and necessary safety for this type of laboratories. (Author)

  14. Cosmic radiation dosimetry onboard aircrafts at the brazilian airspace; Dosimetria da radiacao cosmica no interior de aeronaves no espaco aereo brasileiro

    Energy Technology Data Exchange (ETDEWEB)

    Federico, Claudio Antonio

    2011-07-01

    The objective of this work is the establishment of a dosimetric system for the aircrew in the domestic territory. A technique to perform measurements of ambient dose equivalent in aircrafts was developed. An active detector was evaluated for onboard aircraft use, testing its adequacy to this specific type of measurement as well as its susceptibility to the magnetic and electromagnetic interferences. The equipment was calibrated in standard radiation beams and in a special field of the European Laboratory CERN, that reproduces with great proximity the real spectrum in aircraft flight altitudes; it was also tested in several flights, in an Brazilian Air Force's aircraft. The results were evaluated and compared with those obtained from several computational programs for cosmic radiation estimates, with respect to its adequacy for use in the South American region. The program CARI-6 was selected to evaluate the estimated averaged effective doses for the aircrew who operate in this region. A statistical distribution of aircrew effective doses in South America and Caribe was made, and the results show that a great part of this aircrew members are subjected to annual effective doses that exceed the dose limits for the members of the public. Additionally, a preliminary passive dosemeter, based in thermoluminescent detectors, was proposed; international collaborations with United Kingdom and Italy were established for joint measurements of the ambient equivalent doses in aircrafts. (author)

  15. The FISH chromosome painting technique in Biological Dosimetry : Evolution and applicability; La Tecnica de Pintado Cromosomico mediante FISH en Dosimetria Biologica: Evolucion y Aplicabilidad

    Energy Technology Data Exchange (ETDEWEB)

    Oteo, M.; Real, A.

    2005-07-01

    The capacity of ionising radiation to induce chromosomal aberrations has been used during decades to assess doses in persons accidentally exposed, giving rise to the discipline Biological Dosimetry. the Biological Dosimetry is a complement to the physical methods of dosimetry and in the situations where those are not available represent the only way to asses the doses received. During decades biological dosimetry has used the dicentric score to determine doses, since a good correlation between in vitro and in vivo irradiation results exists and the background yields are low. However, dicentrics yields decrease with time after irradiation. The translocations and insertions represent stable aberrations what means that they do not decrease in further cell divisions. The development at the end of the 80s of the FISH technique (Fluorescence In Situ Hybridization), represented a great step for the applicability of translocations score for biological dosimetry. In this paper, a review of the FISH chromosome painting technique is presented, addressing the facts that have needed to be solve before its routine use in retrospective dosimetry, as well as the aspects that will need further research in the near future. (Author) 54 refs.

  16. 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)

  17. 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.

  18. 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)

  19. Thermoluminescent dosimetry of UV light using ZrO{sub 2}:Gd films; Dosimetria termoluminiscente de la luz UV usando peliculas de ZrO{sub 2}:Gd

    Energy Technology Data Exchange (ETDEWEB)

    Flores D, R.C.; Rivera M, T. [Escuela Superior de Ingenieria Mecanica y Electrica, Unidad Culhuacan-IPN, Av. Santa Ana 1000 C.P. 04430 Mexico D.F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana Unidad Iztapalapa, Av. San Rafael Atlixco 186 C.P. 09340 Mexico D.F. (Mexico); Falcony G, C. [Centro de Investigacion y Estudios Avanzados del IPN, C.P. 07000 Mexico D.F. (Mexico); Garcia H, M.; Martinez S, E. [Instituto de Investigaciones en Materiales-UNAM, C.P. 04510 Mexico D.F. (Mexico)

    2002-07-01

    The samples used for the study are films of zirconium oxide activated with gadolinium (ZrO{sub 2} :Gd) deposited in a glass substrate of square shape, whose dimensions are 1.5 mm thickness and 5 x 5 mm. The Tl curve of ZrO{sub 2} :Gd presented two peaks in 110 and 290 Centigrade degrees. The thermoluminescent response depending on the wavelength presented a maximum in 270 nm. The treatment of optimum thermal erased was obtained for a temperature of 250 Centigrade degrees during 10 minutes. The irradiation time was realized in an interval of 1 to 75 minutes presenting its linear response until a time of 60 minutes. The recurring of the Tl response presented a variation of 1.38% with respect to the average. The fade out of the stored information in the material is 11.11% of standard deviation by a stored period of 7 days in normal working conditions. (Author)

  20. 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

  1. Attributes of a real and computational female thorax phantom for dosimetry; Atributos de um fantoma computacional e real de tronco feminino para dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Maia, Margareth; 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 work describes the construction of an anatomic model that keeps the anthropometrics and anthropomorphic relations of human thorax. The work was developed in two stages. The first one is the construction of a real phantom. The second stage discusses a computational pattern. Due to the large use of ionizing radiation in medical area, the creation of a simulator, the more approximate as possible to the human pattern, proved to be useful. The purpose of the simulator was to contribute to minimizing miscalculation in human treatment procedures, to improve medical image quality and even to serve an academic purposes as a pedagogic pattern. The phantom's construction process was totally handicraft and developed in several stages, which are described as well as the used equivalent materials. The following elements were constructed: twelve thorax vertebras, twenty four ribs, two shoulder blades, two collarbones and the external bone. Also the equivalent muscular tissue, the skin and the mammary gland were built. To create the mammary gland, a plastic prosthesis filled with equivalent mammary tissue was used. Meantime, an anatomic three dimensional model was made to simulate the human thorax. A bone skeleton covered by a muscular and a skin coat composed it. The breast was coupled in anatomic position on left hemi thorax. Computed tomography (CT) images were taken to verify the similarity of density tissue when it was compared to human model. This work was photographically recorded during all stages. The computational thorax phantom was based on a digitalized tomography - in a colored voxels model, each entity represents one tissue and each tissue shows a specific color. The model valuates the density and chemical composition of the tissue. As to the images treatment, a network Internet computer program specially developed for SISCODES was used to support it. In the future this model will be useful to dosimetric studies, medical image equipment calibration, and new equivalent tissues research, among others. (author)

  2. Developing a dosimetry system with alanine at University of Santiago de Compostela; Desarrollo de un sistema de dosimetria con alamina en la Universidad de Santiago de Compostela

    Energy Technology Data Exchange (ETDEWEB)

    Gago Arias, M. A.; Gomez Rodriguez, F.; Gonzalez Castano, D. M.; Peteiro Vilaseco, E.; Lodeiro Remesar, C.

    2013-07-01

    This paper presents the studies realized for the calibration, absorbed dose in water, the signal of Electron Paramagnetic Resonance of dosimeters of alanine, necessary step for the implementation of a service of dosimetry with alanine, traced to the secondary pattern of the Radio physics laboratory (RPL), and linked to the service of resonance Para Magnetic of the University of Santiago de Compostela. (Author)

  3. 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)

  4. Modeling of the system of image portal IVIEWGT for dosimetry applications; Modelizacion del sistema de imagen portal IVIEWGT para aplicaciones de dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Cortes Rodicio, J.; Sanchez Merino, G.; Lope Lope, R.; Ripol Valentin, O.; Martin Gonzalez, T.; Garcia Fidalgo, M. A.

    2013-07-01

    This paper presents the dosimetry of an electronic image portal iViewGT device characterization TM mounted on an accelerator Elekta Synergy for its future application in verification of treatments as well as for the quality control of the throttle. (Author)

  5. 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)

  6. Reproducibility study of thermoluminescent dosemeters for application in personal dosimetry; Estudo da reprodutibilidade de dosimetros termoluminescentes para a aplicacao em dosimetria pessoal

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Beatriz M.; Morimoto, Richard; Menezes, Francisca L.; Ferri, Paulo L.S.; Santos, Osmar A. dos, E-mail: medeirosmbeatriz@gmail.com [Fundacao do Cancer, Rio de Janeiro, RJ (Brazil)

    2016-07-01

    Nowadays in radiotherapy services due to the big concern about the OEIs' safety is made the personal dosimetry of them. And Thermoluminescent Dosimetry is the most used dosimetric technique. It is necessary that the dosimeters are tested for their characterization and response evaluation before being used. One of these tests is the reproducibility test.This study aims to ensure that the dosimetric system analyzed has the same response to the same dose through the criteria presented by the Testing and Calibration Service Evaluation Committee - CASEC / IRD / CNEN contained in the IRD-RT Document Number 002.02 / 2010{sup o}. The groups showed a coefficient of variation equal to 3.6% for irradiated dosimeters with 25 cGy, 2.7% for irradiated dosimeters with 40 cGy, 6.6% for irradiated dosimeters with 50 cGy and 4.1% for dosimeters irradiated with 100 cGy. Since all these values are less than 7.5%, all four dosimeters groups would be accepted by the criteria used. (author)

  7. 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)

  8. Preliminary tests in skull pediatric phantom for dosimetry in computerized tomography; Testes preliminares em um simulador pediatrico de cranio para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Elaine Wirney; Potiens, Maria da Penha de A., E-mail: elainewirney@uso.br, E-mail: mppalbu@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    Computed tomography (CT) is one of the techniques in the field of radiology with striking technological advance in recent years. One reason for this was the increased number of channels associated with the increased power of the X-ray tube. These conditions allowed the equipment high speed in the acquisition of the cuts, reducing the patient exposure time essential characteristic for the increase of its use in pediatric patients. In this context, were developed a new pediatric skull simulator to analyze the results of measurements performed in laboratory and clinic beams with the objective of creation and use of diagnostic reference levels observing risks stochastic effects and assessing the reduction of absorbed doses in patients undergoing growing. Preliminary tests performed in clinical beams showed C{sub w} values: 2.525 ± 0.212 mGy for the developed simulator quoted and 3.362 ± 0.282 mGy for a simulator developed by IPEN called standard, both being between uncertainty values of 8.4% and 14.4% suggested by TRS number 457.

  9. 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.

  10. Absorbed dose distribution of brachytherapy sources through Fricke xylenol gel dosimetry; Distribuicao da dose absorvida de fontes braquiterapicas atraves da dosimetria bidimensional Fricke xylenol gel

    Energy Technology Data Exchange (ETDEWEB)

    Mangueira, T.F.; Almeida, A. de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Departamento de Fisica e Matematica; Costa, J.J.L., E-mail: lucas@ifg.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Goias (IFG), Inhumas, GO (Brazil); Caldas, Linda V.E.; Oliveira, L.N. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Moreira, M.V. [Instituto Ribeiraopretano de Combate ao Cancer (IRPCC), Ribeirao Preto, SP (Brazil)

    2013-07-15

    brachytherapy techniques used throughout the world is derived, or has as a principle the method Paterson-Parker (PP), which ensures the homogeneity of 10% of the treatment plan (target volume), the distance 'h' from the plane formed the source distribution brachytherapy irradiation. Thus, the method ensures that the maximum dose does not exceed 10% of the dose set to satisfy the criteria for uniformity. In this study, we evaluated the method PP measures in dose distribution, having as the Fricke Xylenol Gel dosimeter (FXG), which was irradiated with an orderly distribution of sources of treatment. The distribution was made with eight sources of {sup 137}Cs, distributed in the rules of the PP method, with h = 5.75 mm. The phantom was a distribution of 5 x 5 cm{sup 2} standard spectrophotometer cuvettes (each 1.25 x 1.25 x 3.5 cm{sup 3} optical path length) FXG filled with a total volume of 5 x 5 x 3.5 cm{sup 3}. The phantom was irradiated in a time of 3.3 h resulting in an absorbed dose of 10 Gy in the treatment plan. Then, the FXG was read in a monospectrophotometer and their results were processed in a routine MATLAB Registered-Sign thereby obtaining the dose distribution. The homogeneity was calculated at 7.8% in the treatment plan, which is in accordance with the protocols of IAEA-TECDOC-602. (author)

  11. 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)

  12. 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.

  13. 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.

  14. 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)

  15. 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)

  16. 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)

  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. 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)

  19. 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)

  20. 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)

  1. 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)

  2. Comparative study of Si diodes for gamma radiation dosimetry; Estudo comparativo das respostas de diodos de Si para dosimetria de radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Pascoalino, Kelly Cristina da Silva

    2010-07-01

    In this work it is presented the comparative study of Si diodes response for gamma radiation dosimetry. The diodes investigated, grown by float zone (Fz) and magnetic Czochralski (MCz) techniques, were processed at the Physics Institute of Helsinki University in the framework of the research and development of rad-hard silicon devices. To study the dosimetric response of these diodes they were connected in the photovoltaic mode to the input of a digital electrometer to measure the photocurrent signal due to the incidence of gamma-rays from a {sup 60}Co source (Gammacell 220). The dosimetric parameter utilized to study the response of these devices was the charge, obtained trough the integration of the current signals, as a function of the absorbed dose. Studies of the influence of the pre-irradiation procedures on both sensitivity and stability of these diodes showed that the sensitivity decreased with the total absorbed dose but after a preirradiation of about 873 kGy they became more stable. Radiation damage effects eventually produced in the devices were monitored trough dynamic current and capacitance measurements after each irradiation step. Both samples also exhibited good response reproducibility, 2,21% (Fz) and 2,94% (MCz), obtained with 13 consecutive measurements of 15 kGy compared with the equivalent 195 kGy absorbed dose in one step of irradiation. It is important to note that these results are better than those obtained with routine polymethylmethacrylate (PMMA) dosimeters used in radiation processing dosimetry. (author)

  3. 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)

  4. 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)

  5. 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)

  6. Database to manage personal dosimetry Hospital Universitario de La Ribera; Base de datos para gestionar la dosimetria personal del Hospital Universitario de La Ribera

    Energy Technology Data Exchange (ETDEWEB)

    Melchor, M.; Martinez, D.; Asensio, M.; Candela, F.; Camara, A.

    2011-07-01

    For the management of professionally exposed personnel dosimetry, da La are required for the use and return of dosimeters. in the Department of Radio Physics and Radiation Protection have designed and implemented a database management staff dosimetry Hospital and Area Health Centers. The specific objectives were easily import data from the National Center dosimetric dosimetry, consulting records in a simple dosimetry, dosimeters allow rotary handle, and also get reports from different periods of time to know the return data for users, services, etc.

  7. 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)

  8. Synthesis and characterization of LiF: Mg, Ti for ionizing radiations dosimetry; Sintesis y caracterizacion de LiF: Mg, Ti para dosimetria de radiaciones ionizantes

    Energy Technology Data Exchange (ETDEWEB)

    Lozano R, I. B.

    2011-07-01

    Among the different thermoluminescence materials (Tl), the LiF:Mg, Ti is the most used for dosimetric purposes, because its equivalence to the human tissue, it has an effective atomic number of 8.14, the best known commercial dosemeter of this kind is the TLD-100. However, because this dosimeter is an imported product, is quite expensive for many research groups and hospitals. The purpose of this work is the optimization of its synthesis, as the dosimetric characterization, so it can replace the imported dosimeters. The synthesis of LiF:Mg, Ti is a careful process, since one of the reagents, the ion fluorine is highly corrosive. In this work the synthesis of the LiF:Mg, Ti was done by the molten substance method, was used LiF of analytical grade and the magnesium (Mg) and titanium (Ti) activators were incorporated in aqueous solution. For to optimize the handle of the material Tl, we elaborated pellets and teflon (Ptfe) was used as agglutinate material, in a 2:3 proportion. First was prepared the LiF, incorporating just Mg as dopant with a concentration of 400 parts per million (ppm). After the Ti with concentrations from 15 to 120 ppm was incorporated keeping fixed the concentration of Mg (400 ppm). The morphological and structural characterization of the Tl material were made by scanning electron microscopy and X-ray diffraction. The optimal concentration of Ti, was determined as a function of the radiation dose sensibility of the Tl material. The material prepared with 60 ppm of the Ti showed a higher sensibility. However, also the rest of the preparations had the requirements recommended by the international agencies to be used in ionizing radiations dosimetry. For the dosimetric characterization were used samples with 400 ppm of Mg, 400 ppm Mg and 30 ppm Ti, 400 ppm Mg and 60 ppm Ti. The LiF:Mg showed its dosimetric peak at 240 C, while the LiF:Mg, Ti (30 ppm and 60 ppm Ti) showed their dosimetric peak at 220 C and 222 C respectively. The study of the Tl response as a function of the dose, of the materials prepared, was done with {sup 60}Co gamma radiation, in the dose interval between 1 x 10{sup -4} and 1 x 10{sup 3} Gy. The Tl response as dose function for the LiF:Mg + Ptfe dosimeters, was lineal in the interval from 0.0025 to 50 Gy. The response of the Tl as a function of the dose, for the LiF:Mg, Ti + Ptfe, with 400 ppm Mg, 30 ppm Ti, showed linearity in the interval from 0.0025 to 50 Gy. The Tl response as a function of the dose for the LiF:Mg, Ti + Ptfe with 400 ppm Mg, 60 ppm Ti dosimeters showed linearity in the interval from 0.0025 to 50 Gy. The Tl-100 showed linearity in the dose interval from 0.001 to 10 Gy. The LiF:Mg showed a fading of 3% in two months, the LiF:Mg, Ti (400 ppm Mg, 60 ppm) Ti) showed a lost of information of 6.4% in three months. The Tl materials prepared in this work do not suffer significant changes by the influence of the environmental conditions. (Author)

  9. Contribution of the SLDC to the metrology of the ionizing radiations dosimetry in Mexico; Contribucion del LSCD a la metrologia de la dosimetria de radiaciones ionizantes en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J. T., E-mail: trinidad.alvarez@inin.gob.m [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    The Secondary Laboratory of Dosimetric Calibration (SLDC), assigned to the Metrology Department of Ionizing Radiations of the ININ had its beginnings in the eighties, with the purpose of having a specialized area to develop and to establish measure patterns of the dosimetric magnitudes and units. In the year 2000 the National Center of Metrology of the country, delegated its functions to the SLDC, as regards to develop and to maintain the national patterns in the area of ionizing radiations. In this chapter a brief review is presented on the magnitudes and units used in dosimetry and and absorbed dose, as well as some of the activities of dosimetric calibration that have been made by part of the SLDC to the radiotherapy centers in Mexico and some applications to the nuclear power plant of Laguna Verde. (Author)

  10. 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)

  11. 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)

  12. 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)

  13. 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)

  14. 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)

  15. 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...

  16. On the quantification of soil bioturbation and soil relocation in a mountainous area in S Spain – testing the potential of single-grain OSL techniques

    NARCIS (Netherlands)

    Román Sánchez, A.; Reimann, T.; Vanwalleghem, T.; Temme, A.J.A.M.; Giráldez, J.V.

    2015-01-01

    Soil formation depends on bedrock, climate, relief, vegetation and time. Bioturbation and colluvial soil re-location are important and significant processes that affect the mechanisms and rate of bedrock weathering. The estimation of the relative fraction of bedrock grains which has been mixed in th

  17. OSL dating of the Aterian levels at Dar es-Soltan I (Rabat, Morocco) and implications for the dispersal of modern Homo sapiens

    Science.gov (United States)

    Barton, R. N. E.; Bouzouggar, A.; Collcutt, S. N.; Schwenninger, J.-L.; Clark-Balzan, L.

    2009-09-01

    The Aterian is a distinctive Middle Palaeolithic industry which is very widely spread across North Africa. Its dating and significance have been debated for nearly a century. Renewed interest in the Aterian has arisen because of a recent proposal that its development and spread may be linked to the dispersal of anatomically modern humans. The industry contains technological innovations such as thin bifacially flaked lithic points and pedunculates as well as evidence for personal ornaments and use of red ochre. Such markers as shell beads are believed to be indicative of symbolic behaviour. Dar es-Soltan I on the Atlantic coast of Morocco contains a thick sequence of Aterian deposits that were thought to represent the later stages of development of this industry. New Optically Stimulated Luminescence dates and geomorphological study indicate a much older sequence and so far the earliest yet recorded ages for the Aterian. They suggest an appearance in the Maghreb region during MIS (Marine Isotope Stage) 5.

  18. Quality assurance of the measurements of the activity conducted by the Brazilian Lab of Ionizing Radiation Metrology of the Instituto de Radioprotecao e Dosimetria, Rio de Janeiro, RJ, Brazil; Garantia da qualidade das medicoes da grandeza atividade realizadas pelo Laboratorio Nacional de Metrologia das Radiacoes Ionizantes - Instituto de Radioprotecao e Dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos J. da; Delgado, Jose U.; Iwahara, Akira; Bernardes, Estela Maria O.; Prinzio, Maria Antonieta R. de; Oliveira, Antonio Eduardo de; Poledna, Roberto; Lopes, Ricardo Tadeu [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Measuring systems with reentrant type ionization chamber, has been used as reference systems for storing results of international intercomparisons, these systems offer great stability over several years and absolute methods comparable to those uncertainties. This work are presented the calibration factors of a well-type ionization chamber and their uncertainties, the standardization of various radionuclides which present metrological traceability ensured by key comparisons organized by the International Bureau of Weights and Measures.

  19. Quality control of the prostate tumor dosimetry performed by real-time dosimetry system COMPASS transmission chamber; Control de calidad de la dosimetria de tumores de prostata realizados mediante dosimetria en tiempo real con el sistema de camara de trasmision COMPASS

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, J. M.; Sanchez Cayuela, C.; Casal, M. d.; Pereza, C.; Brosed, M. L.; Sanchez, A.

    2011-07-01

    The most commonly used methodology for the verification of IMRT planning using radiochromic films and specific measures in a homogeneous phantom which move the control points of treatment. This system has the drawback of using a homogeneous model ignores the effect of the heterogeneities and the peculiarities of the patient's anatomy. This coupled with the fact obtain an evaluation in real time of each treatment fraction led us to use the new system COMPASS (I was Dosimetry) for the validation of planning.

  20. Optically stimulated luminescence in KCl:Cu x-irradiated at room temperature

    CERN Document Server

    Bandyopadhyay, P K; Chakrabarti, K

    1999-01-01

    Optically stimulated luminescence (OSL) has been observed in single crystals of KCl:Cu x-irradiated at room temperature. It is shown that electrons are liberated from anion sites during the OSL process. The OSL predominantly involves emission due to radiative transition (d s) of monovalent copper ions present in the lattice. The OSL emission shows a strong temperature dependence indicating a thermally assisted process. Electron-hole recombination followed by energy transfer to the Cu activator is suggested as a possible OSL mechanism in KCl:Cu. Preliminary results of OSL in KBr:Cu are also presented.

  1. 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)

  2. Influence of the curve density relative electron in dosimetry clinic in treatments stereo tactics; Influencia de la curva de densidad electronica relativa en la dosimetria clinica en tratamientos estereotaxicos

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Saiz, C.; Benitez Villegas, E. M.; Casado Villalon, F. J.; Parra Osorio, V.; Bodineau Gil, C.; Garcia Pareja, S.

    2013-07-01

    The objective of this study is to analyze the difference between clinical dosimetry in the treatments with radiosurgery and stereotactic radiotherapy fractional obtained from the relative Electron density curve (Schneider 1996) tabulated and provided with the scanner's radiation therapy. (Author)

  3. 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)

  4. 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)

  5. 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)

  6. 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)

  7. Dosimetry applied in total skin irradiation using an electron beam with 4 MeV nominal energy; Dosimetria aplicada na irradiacao de toda a pele utilizando feixes de eletrons com energia nominal de 4 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Poli, Maria Esmeralda Ramos

    2000-07-01

    This work describes a dosimetric process to a treatment technique used on diseases that affect all body's skin surface, as mycosis fungoides, using total skin irradiation with electron beam with 4 MeV nominal energy. The goals are to improve the uniformity of the dose in the patient, as well to reduce the problems with the overlapping treatment fields, that occurs in conventional treatment that uses 1 meter of focus-skin distance and to reduce the treatment time to the patient. The patient is placed on a rotative base stand up and perpendicular to the beam, distant 2.83 meters from the gantry and he assumes successively 6 positions with 60 degrees of interval between the rotations. In each position the patient receives a couple of beams (angulated at 19.5 degrees above and below the transversal axis in the middle line of the patient). The dosimetric data obtained were compared with the international protocols as AAPM Rep. 23 (AAPM, 1988). The delivered doses in the patient were measured with dosimetric films placed in an anthropomorphic phantom and with thermoluminescent dosimeters placed on patient skin surface. The dose distributions in the phantom show an uniform dose variation in all thickness of interest so, it is possible to utilize this technique in the treatment of the mycosis fungoides. (author)

  8. Report of results of the tests of evaluation of the operation of service of personal dosimetry of the CNLV; Informe de resultados de las pruebas de evaluacion del funcionamiento de servicio de dosimetria personal de la CNLV

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Tovar M, V.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-11-15

    The ININ realized the evaluation of the service of personal dosimetry in the CNLV, in the categories: IV.- (Photons of high energy of {sup 137}Cs) and the VA.- (Particles beta of {sup 90}Sr/{sup 90}Y); in the category IV the test was satisfactory, however in the chart 1 has an underestimation a the American Standard HP over the value true conventional of a 9%; for this irregularity it is recommended to revise the procedures of evaluation of the process and the determination of the chart 1 of the HP. In the category VA, the test is also satisfactory, however the results contrasted with the chart 2 and the HP, the values were overestimated in 29% of the true conventional value, and for that problem is recommended to revise the evaluation procedures in contrast with the values determined by the standard HP. (Author)

  9. Personal and environmental dosimetry of neutrons in a storage facility and humidity probes soil density; Dosimetria personal y ambiental de neutrones en una instalacion de almacenamiento de sondas de densidad y humedad de suelos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Fuste, M. J.; Amgarou, K.; Dan Pedro, M. de; Garcia-Orellana, J.; Domingo, C.

    2011-07-01

    The equipment operators are professionally exposed to radiation and the premises where stored are considered controlled areas. Although control of the personal doses of gamma radiation received by the operators during the operation, maintenance and storage of the probes is required and is performed by dosimetry services officially approved, the control of personal and environmental doses due to neutrons generally omitted, since they are small in comparison to the gamma dose.

  10. 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)

  11. 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)

  12. Occupational dosimetry in rela-time hemodynamics rooms. Usefulness of system dose-aware as a tool for learning; Dosimetria ocupacional en tiempo real en salas de hemodinamica. Utilidad del sistema dose-aware como herramienta formativa

    Energy Technology Data Exchange (ETDEWEB)

    Pinto Monedero, M.; Rodriguez Cobo, C.; Pifarre Martinez, X.; Ruiz Martin, J.; Barros Candelero, J. M.; Goicolea Ruigomez, J.; Diaz Blaires, G.; Garcia lunar, I.

    2013-07-01

    The work pursues a dual objective: on the one hand, to know the typical doses that practitioners of a dosimetry system interventional cardiology receive in real time, which allows to know the dose rate at any time; on the other hand, to assess the validity of this system of dosimetry, together with a simultaneous recording of proceedings for further analysis, as a teaching tool from the point of view of radiation protection. (Author)

  13. 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)

  14. 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)

  15. 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)

  16. Management system of personnel dosimetry based on ISO 9001:2008 for medical diagnostic; Sistema de gerenciamento da dosimetria pessoal baseado na ISO 9001:2008 para radiodiagnostico medico

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Carlos E.B.; Gerber Junior, Walmoli; Jahn, Tiago R.; Hahn, Tiago T.; Fontana, Thiago S.; Bolzan, Vagner, E-mail: brasilrad@brasilrad.com.br [Brasilrad Consultoria em Radioprotecao, Florianopolis, SC (Brazil)

    2013-07-01

    MDose is a computer management system of personal dosimetry in diagnostic radiology services physician based on ISO 9001:9008 management system. According to Brazilian law all service radiology should implement a control of personal dosimetry in addition to radiation doses greater than 1.5 mSv/year service should do research of high dose, which is to identify the causes the resulting dose increase professional. This work is based on the use of the PDCA cycle in a JAVA software developed as a management method in the analysis of high doses in order to promote systematic and continuous improvement within the organization of radiological protection of workers.

  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. Thermoluminescence of metal oxides and its applications to the dosimetry of low energy ionizing radiation; Termoluminiscencia de oxidos metalicos y su aplicacion a la dosimetria de la radiacion ionizante de baja energia

    Energy Technology Data Exchange (ETDEWEB)

    Azorin N, J. [CICATA-IPN, 11500 Mexico D.F. (Mexico); Rivera M, T. [Universidad Autonoma Metropolitana-Iztapalapa, 09340 Mexico D.F. (Mexico); Falcony G, C. [CINVESTAV-IPN, DEpartamento de Fisica, 07300 Mexico D.F. (Mexico); Martinez S, E.; Garcia H, M. [Universidad Nacional Autonoma de Mexico, Instituto de Investigaciones en Materiales, 04510 Mexico D.F. (Mexico)

    1999-07-01

    There are presented the results obtained since 1997 at present in the project Study of the thermoluminescence of metal oxides and its applications to the dosimetry of ionizing radiation. Its have been developed ZrO{sub 2} films without doping and doped with Eu, Tb, and Mn as well as Al{sub 2}O{sub 3} films without doping and doped with Na. The results obtained to the irradiated films of ZrO{sub 2} with ultraviolet and visible lights have been satisfactory. The Al{sub 2}O{sub 3} in film form showed to be a promising material for the measuring ultraviolet light and the pellets of ZrO{sub 2} + Ptfe for X-rays and low energy gamma rays. (Author)

  19. Thermoluminescence of films of metal oxides and its application to the low energy ionizing radiation dosimetry; Termoluminiscencia de peliculas de oxidos metalicos y su aplicacion a la dosimetria de la radiacion ionizante de baja energia

    Energy Technology Data Exchange (ETDEWEB)

    Azorin N, J.; Rivera M, T.; Furetta, C. [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, 09000 Mexico D.F. (Mexico); Falcony G, C. [Departamento de Fisica, Centro de Investigacion y Estudios Avanzados, IPN, 07000 Mexico D.F. (Mexico); Martinez S, E.; Garcia H, M. [Instituto de Investigaciones en Materiales, UNAM, 04510 Mexico D.F. (Mexico)

    2002-07-01

    The obtained results from 1997 to date in the project {sup S}tudy of the thermoluminescence of metal oxides and their application to the ionizing radiation as regards to the development of ZrO{sub 2} and of Al{sub 2}O{sub 3} doped and without doped films with rare earths are presented. The obtained results irradiating ZrO{sub 2} and of Al{sub 2}O{sub 3} films with ultraviolet light and visible light have been satisfactory; whereas these materials have resulted promising to measure beta particles, X-rays and low energy gamma rays. (Author)

  20. New method of preparation of CaSO{sub 4}: Dy for ionizing radiation dosimetry; Nuevo metodo de preparacion del CaSO{sub 4}: Dy para dosimetria de radiacion ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Roman L, J.; Rivera M, T.; Alarcon F, G.; Guzman M, J. [CICATA-IPN, 11500 Mexico D.F. (Mexico); Azorin N, J.; Sosa F, R. [UAM-I, 09340 Mexico D.F. (Mexico); Serrano F, A.K. [Hospital Juarez General de Mexico, 07760 Mexico D.F. (Mexico)]. e-mail: holand_jeos@hotmail.com

    2008-07-01

    In this work some results of the characterization of solid state materials exposed at a gamma radiation beam coming from a {sup 60} Co bomb for medical use are presented. These thermoluminescent dosemeters are prepared and proposed for the ionizing radiations dosimetry using the thermoluminescence method. The passive dosemeters of CaSO{sub 4}: Dy are developed in the polycrystalline powder form being used a new synthesis route by means of the precipitation method. To determine the sensibility of the pellets of CaSO{sub 4}: Dy before gamma radiation, these were exposed before a gamma radiation beam coming from a {sup 60} Co bomb. The morphological and structural characteristics were also studied and present two in this work. (Author)

  1. 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.

  2. Biokinetics analysis of I-131 and cytogenetic dosimetry in patients, after radionuclide administration for thyroid; Analise biocinetica do iodo-131 e dosimetria citogenetica em pacientes, apos administracao do radionuclideo para o tratamento de cancer de tireoide

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    Nascimento, Ana Cristina de Holanda

    1996-07-01

    Thyroid cancer patients are submitted to an oral administration of {sup 131} I in order to eliminate remanescent thyroid tissue, after subtotal thyroidectomy. The average activity administered in this treatment is 3.7 GBq (ablation dose), with significant irradiation of body tissues. However, there are no conclusive results on the literature about the radiation absorbed dose of these patients. The metabolic behaviour of radioiodine in 4 patients submitted to {sup 131} I ablation therapy doses was studied, through measurements of {sup 131} I in total body, thyroid and urine samples. Cytogenetic estimates of the radiation doses of these patients were obtained through chromosomal aberration analysis in the peripheral blood lymphocytes. Our results suggest that ten days after ablation dose, almost all remanescent thyroid tissue will be eliminated and {sup 131} I will be homogeneously distributed through the patient's body. The retention of {sup 131} I in the body after the first ten days following the ablation dose may be mathematically represented by the sum of two exponential terms: the first and shorter one with a biological half-life approximately 3.2 days (effective half-life = 2.3 days) and the second one, with a biological half-life of approximately 26 days (effective half-life = 6.2 days). The absorbed dose using the average of the observed chromosomal aberrations yields in blood samples of all patients was estimated in the range of 0,3 to 0,4 Gy. (author)

  3. 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)

  4. Analysis behaviour of free radicals produced by ionizing radiations in human blood by EPR for biological dosimetry in patients; Analisis del comportamiento de los radicales libre en la radiolisis de la sangre por EPR para dosimetria biologia en pacientes

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, O. O.; Almanza, A.; Plazas, M. M. C.

    2006-07-01

    In this work is analyzed the biological dosimetry of the free radicals produced by ionizing radiations in human blood obtained by EPR and the biological behaviour of samples In-Vitro, with Rh: O+, in tubes with EDTA (Acid Etilen Diamino Tetracetic) the samples was extracted of the main investigator, these samples were radiated with gammas of ''60Co of a Theratron 780 between plates of PMMA to a depth of Z{sub m}ax of 0.5 cm and between doses 1 to 25 Gy. In these results the behaviors of signal the free radicals presented a increasing a their intensity depending on applied dose, of equal way are results of the biologic dosimetry displayed in sanguineous populations like. White Globules, Red. Platelets etc, to being compared with Resonance Paramagnetic Electronic (EPR). The results show changes in sanguineous populations in high doses (D>10 Gy) in the case of lymphocytes, granulocitos, macusanita, plaquetas, hemoglobina, haematocrit with change similarly in medium and low doses (D>10Gy) in linfocites, platelets, granulocytes, monocytes and the haematocrit. A sanguineous sample without radiating analyzes by EPR giving the presence of signals with values of g=2.13 2,41 in blood. For the first certain value of g authors have associated it to free radicals like: globin (Fe(IV)=0) or Cu''+ incorporated to the ceruloplasmin molecule. (Author)

  5. Low temperature dosimetry in LiF: Mg, Cu, P and CaSO{sub 4}: Dy doped crystals; Dosimetria de baja temperatura en cristales dopados LiF: Mg, Cu, P y CaSO{sub 4}: Dy

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E.; Ramos B, S.; Negron M, A.; Rivera, T. [Instituto de Ciencias Nucleares, UNAM, A.P. 70-543, 04510 Mexico D.F. (Mexico)

    2000-07-01

    It is presented a behavior study of LiF solid dosemeters doped with Mg, Cu and P also polycrystalline samples of CaSO{sub 4} with Dy sinterized in laboratory, both of them were subjected at low temperature. In order to analyse linear behavior to the dose of these dosemeters, it was used thermoluminescence. These materials were exposed to gamma radiation coming from a Co-60 source. The samples were irradiated at dose rates 1.08 {+-} 0.01 Gy/min at liquid nitrogen temperature (LNT) and also the response of dosemeters are compared at ambient temperature and LNT. (Author)

  6. X-ray dosimetry in mammography for Mo/Mo combination utilizing Compton spectrometry;Dosimetria de raios X em mamografia para combinacao Mo/Mo utilizando espectrometria Compton

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Jose Neres de; Terini, Ricardo Andrade, E-mail: rterini@pucsp.b [Pontificia Univ. Catolica de Sao Paulo (PUC-SP), SP (Brazil). Dept. de Fisica; Herdade, Silvio Bruni [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia. Secao Tecnica de Desenvolvimento em Tecnologia em Saude; Furquim, Tania Aparecida Correia [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia. Secao Tecnica de Aplicacoes em Diagnostico por Imagem

    2010-08-15

    Objective: to compare mammography benefit and X-ray induced cancer risk, one should investigate absorbed doses. For this purpose, spectra of primary X-ray beams from a clinical mammography equipment were determined for Mo/Mo target/filter combination, using Compton spectrometry and average glandular dose (AGD) in a BR-12 breast phantom was evaluated. Material and Method: a CdTe detector was used for spectrometry of X-ray beams Compton scattered {approx} 100 deg, by a PMMA cylinder, for different depths inside the BR-12 phantom and voltages between 28 and 35 kV. The reconstruction of the primary beam spectra from the measured ones was followed by the determination of AGD. Results: half-value layer values determined by spectra resulted 0.39 to 0.45 mmAl, and by ionization chamber, 0.38 to 0.42 mmAl, respectively, for beams incident on the phantom surface. The AGDN normalized per unitary incident air kerma, on the BR-12 surface, ranged from 0.156 to 0.226. Conclusion: the percentage deviation of AGD{sub N}, relative to the chamber measurements, ranged from 1% to 3%. The utilized method is a good alternative to determine AGD{sub N} and depth-dose distributions in breast phantoms. (author)

  7. X-ray dosimetry in mammography for W/Mo and Mo/Mo combinations utilizing Compton spectrometry;Dosimetria de raios X em mamografia para combinacao W/Mo e Mo/Mo utilizando espectrometria Compton

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Jose N. [Pontificia Univ. Catolica de Sao Paulo (PUC/SP), SP (Brazil). Curso de Fisica; Terini, Ricardo A. [Pontificia Univ. Catolica de Sao Paulo (DF/PUC/SP), SP (Brazil). Dept. de Fisica; Herdade, Silvio B.; Furquim, Tania A.C. [Universidade de Sao Paulo (IEE/USP), SP (Brazil). Inst. de Eletrotecnica e Energia

    2009-07-01

    Mean Glandular Dose (MGD) cannot be measured directly in mammography equipment. Therefore, methods based on Compton spectrometry are alternatives to evaluate dose distributions in a standard breast phantom, as well as mean glandular dose. In this work, a CdTe detector was used for the spectrometry measurements of radiation scattered by compton effect, at nearly 90, by a PMMA cylinder. For this, the reconstruction of primary beam spectra from the scattered ones has been made using Klein-Nishina theory and Compton formalism, followed by a determination of incident air kerma, absorbed dose values in the breast phantom and, finally, MGD. Incident and attenuated X-ray spectra and depth-dose distributions in a BR-12 phantom have been determined and are presented for the mammography range (28 to 35kV), showing good agreement with previous literature data, obtained with TLD. (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. 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)

  10. Dosimetry of irradiated foods and extraction of polyminerals from herbs and seasonings (Guajillo chili, oregano, jamaica, arnica, and camomile); Dosimetria de alimentos irradiados y extraccion de poliminerales de hierbas y condimentos (Chile guajillo, oregano, jamaica, arnica y manzanilla)

    Energy Technology Data Exchange (ETDEWEB)

    Pineda C, S.; Gomez B, C. [Estudiante de la Facultad de Quimica, UNAM (Mexico); Calderon, T.; Cruz Z, E. [Depto. de Quimica Agricola-Geologia-Geoquimica, Universidad Autonoma de Madrid, 28049 (Spain)

    2002-07-01

    Nowadays, in developed countries the irradiation technology is a process used in food treatments for sterilization and diminishing of the microbiological charge, as well as to extend the storage life. In Mexico, the food irradiation, spices and seasonings has been officially approved since 1995, recognizing as an adequate technological process for foods. Taking advantage of knowledge about solids and due to the natural growth of the spices, herbs, etc. these contain minerals which can providing important information of its radiological history, moreover these type of materials do not degrade them preserving by long time periods. In this work, a methodology for the extraction of poly minerals in foods, such as oregano, guajillo chili, jamaica, arnica and camomile is presented. For obtaining the poly mineral, the samples were treated with an ethanol-water solution, in constant stirring during 12 hours at room temperature depending on the sample under treatment. It was used oxygenated water and distilled for washing and acetone for achieving a good drying. The minerals were processed by gamma radiation in the Nuclear Sciences Institute of the UNAM. The brilliance curves of spices and herbs, using a Tl reader of Harshaw 3500 were obtained, the emissions are located between 60 and 350 Centigrade. Previously the extraction of poly mineral was realized and they were divided in same parts for doses between 2 and 10 KGy, this last value according to the Mexican Official Standard considering a fraction without irradiating as reference. The identification of the mineral fraction by diffraction will complement the composition information. We are grateful to the donation of seasonings samples provided by the Tres Villas Natural Seasonings enterprise, Toluca plant, State of Mexico and the Academic Exchange Office at UNAM. (Author)

  11. Phototherapy with low intensity laser in carrageenan-induced acute inflammatory process in mice paw - dosimetry studies; Fototerapia com laser em baixa intensidade em processo inflamatorio agudo induzido por carragenina em pata de camundongos - estudos de dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Meneguzzo, Daiane Thais

    2010-07-01

    The importance of modulation of inflammation on the treatment of inflammatory diseases and the difficulty in determining the laser irradiation parameters has led us to study the effects of different protocols of phototherapy with low intensity laser (power, energy, time and place of irradiation) in the treatment and prevention of edema in acute inflammatory process using the experimental model of paw edema induced by carrageenan (CGN) in three strains of mice (Balb-c, Swiss and C57BL/6). The first stage of the study evaluated different combinations of energy (1J and 3J) with different powers (30, 60 and 100mW) in Balb-C mice paw irradiated 1 and 2h after injection of CGN. The second stage studied different combinations of location (foot, inguinal lymph nodes and both) and exposure time (2 and 1h before, 1h and immediately before the CGN, 1 and 2h and 3.5 and 4.5h after CGN) using fixed irradiation parameters (1J, 100mW, 35J/cm{sup 2}, spot area of 0.028 cm{sup 2}). The third stage compared different strains of mice Balb-c and C57BL/6) in the best local and time parameters found in step 2. At all stages, we evaluated the change in paw volume by plethysmography and inflammatory infiltrate by histomorphometry or analysis of myeloperoxidase (MPO). The results showed that laser phototherapy treated and prevented edema and modulated the inflammatory process with paw and inguinal lymph nodes irradiations accordingly with the parameters and mice strain used. (author)

  12. Gamma and electron high dose dosimetry with rad-hard Si diodes; Dosimetria de altas doses de raios gama e eletrons com diodos de Si resistentes a danos de radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Pascoalino, Kelly Cristina da Silva

    2014-07-01

    In this work the main dosimetric characteristics of rad-hard Float Zone (FZ) and magnetic Czochralski (MCz) diodes to electrons (1.5 MeV) and gamma ({sup 60}Co) radiation are evaluated. The dosimetric system proposed is based on electrical current measurements due to radiation interactions on the devices. The batch response uniformity was studied for the n-type FZ diodes irradiated with gamma rays. The coefficient of variation of the current measurement was about 1.25% at 5 kGy of accumulated dose. A sensitivity decrease with the increase of the accumulated dose (Total Ionizing Dose - TID) was observed for both FZ and MCz diodes. For gamma irradiation, these effect is more pronounced for n-type or smaller resistivity diodes. Two types of dosimetric probe were used on the electron irradiation procedures, one of them specially designed to avoid the deterioration of the electrical contacts and the diodes metallization. The sensitivity of the preirradiated FZ and MCz diodes fell about 10% and 40%, respectively, during electron irradiation at 1.25 MGy of accumulated dose. The effect of electron radiation damage on the electrical properties of the diodes was studied by the means of leakage current and capacitance measurements as a function of bias voltage. The leakage current increases with the accumulated dose but does not contributes significantly to the current signal, since the diodes are operated in photovoltaic mode, without bias voltage. For the MCz diode no change in the full depletion voltage was observed, which indicates its higher tolerance to radiation-induced damage, as expected. During electron irradiation the temperature increases and in order to determine its influence for the current signals, the leakage current values were extrapolated up to 35 °C. The contribution does not exceed 0.1% for FZ and MCz diodes. The effect of the radiation type, electrons or gamma rays, on the pre dose procedures was analyzed for the FZ n-type device and was observed that the electron pre-irradiation is more efficient regarding the sensitivity decrease. The present work indicates the potential application of FZ and MCz diodes as dosimeters in gamma rays and in electron routine irradiation processes. It is worth noting that the proposed system advantage relies on the possibility of real-time monitoring of electron accelerator parameters. (author)

  13. Reconstructive dosimetry and radiation doses evaluation of members of the public due to radiological accident in industrial radiography; Dosimetria reconstrutiva e avaliacao de dose de individuos do publico devido a acidente radiologico em radiografia industrial

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Camila Moreira Araujo de

    2016-07-01

    Radiological accidents have occurred mainly in the practices recognized as high risk radiological and classified by the IAEA as Categories 1 and 2, and highlighted the radiotherapy, industrial irradiators and industrial radiography. In Brazil, since there were five major cases in industrial radiography, which involved 7 radiation workers and 19 members of the public, causing localized radiation lesions on the hands and fingers. One of these accidents will be the focus of this work. In this accident, a {sup 192}Ir radioactive source was exposed for more than 8 hours in the workplace inside a company, exposing radiation workers, individuals of the public and people from the surrounding facilities, including children of a school. The radioactive source was also handled by a security worker causing severe radiation injuries in the hand and fingers. In this paper, the most relevant and used techniques of reconstructive dosimetry internationally are presented. To estimate the radiation doses received by exposed individuals in various scenarios of radiological accident in focus, the following computer codes were used: Visual Monte Carlo Dose Calculation (VMC), Virtual Environment for Radiological and Nuclear Accidents Simulation (AVSAR) and RADPRO Calculator. Through these codes some radiation doses were estimated, such as, 33.90 Gy in security worker's finger, 4.47 mSv in children in the school and 55 to 160 mSv for workers in the company during the whole day work. It is intended that this work will contribute to the improvement of dose reconstruction methodology for radiological accidents, having then more realist radiation doses. (author)

  14. Occupational dosimetry in real time hemodynamic rooms. utility of the system Dose-aware as a training tool; Dosimetria ocupacional en tiempo real en salas de hemodinamica. Utilidad del Sistema Dose-Aware como herramienta formativa

    Energy Technology Data Exchange (ETDEWEB)

    Pinto Monedero, M.; Rodriguez Cobo, C.; Pifarre Martinez, X.; Ruiz Martin, J.; Barros Candelero, J. M.; Goicolea Ruigomez, J.; Diaz Blaires, G.; Garcia Lunar

    2014-02-01

    This paper presents the results from a study in a real time dosimetry system used in the catheter laboratory room of our center. The objective was to know the occupational doses per procedure, on the one hand, and, on the other hand, to evaluate its utility as a learning tool for radiation protection purposes with the simultaneous video recording of the interventions. 83 diagnostic and therapeutic procedures were analyzed, and an average dose per procedure of 0,37 {mu}Sv and 0,10 {mu}Sv for the main cardiologist and nurse were obtained, respectively. 36 of these interventions were also recorded and the images were synchronized with the dosimetric information stored and the dosimetry system. The findings were presented to the interventional cardiology team in a learning session. They showed a high level of satisfaction with this new method of optimizing the occupational doses through a customized learning session. (Author)

  15. 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.

  16. 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.

  17. Dating by fission track method: study of neutron dosimetry with natural uranium thin films; Datacao com o metodo dos tracos de fissao: estudo da dosimetria de neutrons com filmes finos de uranio natural

    Energy Technology Data Exchange (ETDEWEB)

    Iunes, P.J.

    1990-06-01

    Fission track dating is described, focalizing the problem of the decay constant for spontaneous fission of {sup 238} U and the use of neutron dosimetry in fission track analysis. Experimental procedures using thin films of natural uranium as neutron dosimeters and its results are presented. The author shows a intercomparison between different thin films and between the dosimetry with thin film and other dosimetries. (M.V.M.). 52 refs, 12 figs, 9 tabs.

  18. 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)

  19. 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)

  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. Development of virtual anthropomorphism of head mathematical model for using in dosimetry computerized simulation; Desenvolvimento de modelo matematico antropomorfico virtual de cabeca para utilizacao em simulacao computacional de dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Cassola, V.F.; Hoff, G.; Streck, E.E. [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil). Faculdade de Fisica. Grupo de Experimentacao e Simulacao Computacional em Fisica (GESiC)]. E-mail: ghoff@pucrs.br

    2004-07-01

    This paper shows the development of a virtual anthropomorphous model of head, considering different tissue composition, based in Nuclear Magnetic Resonance (NMR) images. The head original images were acquired in an equipment of NMR GE Sigma Horizon LX 1.5 T Echo Speed, available in the clinic of diagnosis for image SIDI. These images were segmented using routines developed in C++ language. The generated model is a group of 124 matrices of sequential data in format ASCII, where 26 indices evidence different structures. (author)

  2. 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)

  3. Thermoluminescent dosimetry of beta radiations of {sup 90} Sr/ {sup 90} Y using ZrO{sub 2}: Eu; Dosimetria termoluminiscente de radiaciones beta de {sup 90} Sr/ {sup 90} Y usando ZrO{sub 2}: Eu

    Energy Technology Data Exchange (ETDEWEB)

    Olvera T, L.; Azorin N, J.; Barrera S, M.; Soto E, A.M. [UAM-I, 09340 Mexico D.F. (Mexico); Rivera M, T. [CICATA-IPN, Legaria 694, 11500 Mexico D.F. (Mexico)

    2005-07-01

    In this work the results of studying the thermoluminescent properties (TL) of the doped zirconium oxide with europium (ZrO{sub 2}: Eu{sup 3+}) before beta radiations of {sup 90}Sr/ {sup 90}Y are presented. The powders of ZrO{sub 2}: Eu{sup 3+} were obtained by means of the sol-gel technique and they were characterized by means of thermal analysis and by X-ray diffraction. The powders of ZrO{sub 2}: Eu{sup 3+}, previously irradiated with beta particles of {sup 90}Sr/ {sup 90}Y, presented a thermoluminescent curve with two peaks at 204 and 292 C respectively. The TL response of the ZrO{sub 2}: Eu{sup 3+} as function of the absorbed dose was lineal from 2 Gy up to 90 Gy. The fading of the information of the ZrO{sub 2}: Eu{sup 3+} was of 10% the first 2 hours remaining almost constant the information by the following 30 days. The ZrO{sub 2} doped with the (Eu{sup 3+}) ion it was found more sensitive to the beta radiation that the one of zirconium oxide without doping (ZrO{sub 2}) obtained by the same method. Those studied characteristics allow to propose to the doped zirconium oxide with europium like thermoluminescent dosemeter for the detection of the beta radiation. (Author)

  4. 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)

  5. 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.

  6. 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.

  7. 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)

  8. 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)

  9. 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)

  10. Software for dosimetry hypothyroid patients treated with I131 pick up and using probe gamma camera; Software para la dosimetria de pacientes hipertiroideos tratados con 131I utilizando sonda de captacion y gammacamara

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Felstrom, D.; Luis simon, J.; Reyes Garcia, R.; Derecho Torres, P.; Herrador Cordoba, M.

    2015-07-01

    In this communication the process recently implemented in our hospital for pre and post treatment of patients treated with I-131 in benign diseases of the thyroid gland internal dosimetry is described. We have developed a proprietary software that facilitates the process of dosimetry. Through scans Planar or pictures Spect be determines the mass of the gland thyroid. In function of the mass, is calculated by Monte Carlo the media power absorbed by disintegration of the I-131 in said gland endocrine. (Author)

  11. 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.

  12. 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)

  13. Radiological response and dosimetry in physical phantom of head and neck for 3D conformational radiotherapy; Resposta radiologica e dosimetria em phantom fisico de cabeca e pescoco para radioterapia conformacional 3D

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Larissa

    2013-07-01

    Phantoms are tools for simulation of organs and tissues of the human body in radiology and radiotherapy. This thesis describes the development, validation and, most importantly, the use of a physical head and neck phantom in radiology and radiotherapy, with the purpose of evaluating dose distribution using Gafchromic EBT2 film in 15 MV 3D conformal radiotherapy. The work was divided in two stages, (1) development of new equivalent tissues and improvement of the physical phantom, and (2) use of the physical phantom in experimental dosimetry studies. In phase (1) parameters such as mass density, chemical composition of tissues, anatomical and biometric measurements were considered, as well as aspects of imaging by computed tomography (CT) and radiological response representation in Hounsfield Units (HU), which were compared with human data. Radiological experiments of in-phantom simulated brain pathologies were also conducted. All those results matched human-sourced data, therefore the physical phantom is a suitable simulator that may be used to enhance radiological protocols and education in medical imaging. The main objective in phase (2) was to evaluate the spatial dose distribution in a brain tumor simulator inserted inside the head and neck phantom developed by the Ionizing Radiation Research Group (NRI), exposed to 15 MV 3D conformal radiotherapy, for internal dose assessment. Radiation planning was based on CT images of the physical phantom with a brain tumor simulator made with equivalent material. The treatment planning system (TPS), CAT3D software, used CT images and prescribed a dose of 200 cGy, distributed in three fields of radiation, in a T-shaped pattern. The TPS covered the planning treatment volume (PTV) with 97% of the prescribed dose. A solid water phantom and radiochromic Gafchromic EBT2 film were used for calibration procedures, generating a dose response curve as a function of optical density (OD). After calibration and irradiation, the film samples were scanned and digitised, yielding OD data, standard deviation and dose response versus OD. The spatial dose profile reached 70% to 120% of the prescribed dose. Such data was plotted and analysed, showing layers dotted with hot spots. Despite the layered profile, as opposed to the smooth dose profile from the TPS, internal doses in the tumor were within a 5% deviation of the 214.4 cGy evaluated by the TPS. In the gamma index analysis, 83.2% of the points with gamma values smaller than 1 (3%/3 mm) between experimental values and TPS data. The tool set composed by the physical phantom and by the film dosimeters was, therefore, suitable for validation of internal doses in radiotherapy protocols. (author)

  14. Results of the Service of External Dosimetry of the Centro de Proteccion e Higiene de las Radiaciones (CPHR), Cuba during the biennium 2010 - 2011; Resultados del servicio de dosimetria externa del CPHR durante el bienio 2010-2011

    Energy Technology Data Exchange (ETDEWEB)

    Molina Perez, Daniel; Verdecia Sanchez, Maribel; Castro Soler, Ailza; Farrada Neyra, Yamilia, E-mail: daniel@cphr.edu.cu [Laboratorio de Dosimetria Externa (LDE), Centro de Proteccion e Higiene de las Radiaciones (CPHR), La Habana (Cuba)

    2013-07-01

    The Service of Personal Dosimetry of the External Dosimetry Laboratory of the Centro de Proteccion y Higiene de las Radiaciones - CPHR of Cuba works with an automatic RADOS TLD system and includes the surveillance of the doses of whole body and extremities for photon radiation. The work presents the results of the service in the period 2010-2011, showing data related to the number and distribution of workers monitored for areas. The levels of occupational exposure area analyzed using various indicators such as: annual average dose for areas, number of workers who receive annual doses greater than zero, distribution of workers by dose intervals, and others. These indicators are compared with previous periods and with the values published by the UNSCEAR. In general, the average annual dose for all areas was less than 1 mSv for whole body and 3 mSv for hands. The number of exposed workers experienced significant variation from one year to another, considerably decreasing from 60% to 12% of the total. The work presents an analysis of this behavior and highlights that the country guarantees the personal dosimetry to 100% of exposed workers and that the results of the occupational exposure are within the established requirements.

  15. 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)

  16. 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)

  17. Verification of the dose in the inspection modules of Co-60 from Mexicali, B.C.N. through thermoluminescent dosimetry; Verificacion de la dosis en los modulos de inspeccion de Co-60 de Mexicali, B.C. mediante dosimetria termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Cruz C, D.; Azorin, J.; Rivera, T. [UAM-I, 09340 Mexico D.F. (Mexico)

    2005-07-01

    On the February and April 2005 months, there entered in operation two inspection modules, in the mexican border city of Mexicali. B.C.N., those which they work based on gamma rays, emitted by sources of {sup 60} Co; this fact generate a concern, on the part of the population of this city. Soon after these events, a group of personages of the local politics, they began a campaign, in favor of closing these modules, based on the supposition, of that the emitted radiation by these sources, represents a danger for health of people that uses the international crossing located to a side of the porter lodge 1, as well as of the population in general. As service to the community border of Mexico specifically to the population of Mexicali, B.C.N. city, inhabitants of this city, municipal, state and federal authorities and, the outstanding preoccupation of the Republic Senate (Commission of Border Affairs), the National Commission of Nuclear Security and Safeguards (CNSNS) they requested the support of the Metropolitan Autonomous University (UAM) and of the National Polytechnic Institute (IPN) to verify the radiation levels in the facilities of the sources of {sup 60} Co of the porter lodges of Mexicali-Calexico proceeding to the monitoring of this facilities in the period of 14-17 June 2005, 17 using thermoluminescent dosemeters elaborated in Mexico. (Au0010th.

  18. Calculation of uncertainties in the protocol of dosimetry for Co 60 beams in Radiotherapy; Calculo de incertidumbres en el protocolo de dosimetria para haces de Co 60 en Radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez M, S.; Carrera M, F.; Sanchez S, J. [Hospital Juan Ramon Jimenez, Ronda Norte s/n 21005 Huelva (Spain)

    1998-12-31

    The objective in this work is to show how the uncertainty is possible to know in the determination of the absorbed dose in Co 60 photon beams and to establish in a rational form, tolerance levels for this. It is took as base the spanish protocol of dosimetry in Radiotherapy. We have been centered in a Co 60 beam. We utilized the statistical theory of little samples. We allowed to suggest a new approach about the treatment of the tolerance levels and the uncertainty of the measurement. After two years of experience in the practical hospitable application we have gotten to put around 1 % uncertainty in the absolute dosimetry of the Co 60 beam. The presented protocol allows to execute the accuracy requirements in the determination of absorbed doses. (Author)

  19. Characterization of jade and silicates of the jade family for application in radiation dosimetry; Caracterizacao do jade e dos silicatos da familia do jade para aplicacao em dosimetria das radiacoes

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Adeilson Pessoa de

    2007-07-01

    The main dosimetric properties of jade and of Brazilian silicates of the jade family were studied for application in radiation dosimetry of high doses. Jade is a common denomination of two different silicates: jadeite, Na Al(Si{sub 2}O{sub 6}), and nephrite, Ca{sub 2}(Mg, Fe){sub 5}(Si{sub 4}O{sub 11}){sub 2} (OH){sub 2}, that belong to the subclasses of the pyroxenes and amphiboles respectively. The jade samples studied in this work were from: Austria, New Zealand, United States and Brazil. The Brazilian silicates of the jade family studied in this work were the amphiboles: tremolite,Ca{sub 2}Mg{sub 5}(Si{sub 4}O{sub 11}){sub 2}(OH){sub 2} e actinolite, Ca{sub 2}Fe{sub 5}(Si{sub 4}O{sub 11}){sub 2}(OH){sub 2}; and the pyroxenes: rhodonite, MnSiO{sub 3} and diopside, Ca Mg(Si{sub 2}O{sub 6}). The mineralogical and chemical composition of these materials were obtained using the neutron activation analysis and X-ray diffraction techniques. The main dosimetric properties (emission curves, calibration curves, reproducibility, lower detection limits, angular and energy dependence, etc) were studied using the thermoluminescent (T L), thermally stimulated exo-emission (TSEE) and electronic paramagnetic resonance (EPR) techniques. The jade-Teflon and the silicate-Teflon samples present two T L peaks around 115 deg C (peak 1) and 210 deg C (peak 2). The calibration curves of the studied materials present a linear behaviour between 0.5 Gy and 1 kGy. The TSEE emission peak occurs at 240 deg C for all samples, and the calibration curves present a sub linear behaviour between 100 Gy and 20 kGy. In the case of the EPR technique, only jade USA has a potential application for radiation dosimetry. A static computational simulation of the most probable intrinsic and extrinsic defects in rhodonite was also realized. Among the basic defects, the Schottky defects of rhodonite are the most probable to occur and, among the extrinsic defects, the divalent and trivalent dopants present the best possibility of inclusion in rhodonite. (author)

  20. 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)

  1. 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

  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. 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)

  4. Evaluation of a new pencil-type ionization chamber for dosimetry in computerized tomography beams; Avaliacao de uma nova camara de ionizacao tipo lapis para dosimetria em feixes de tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Maysa C. de; Neves, Lucio P.; Silva, Natalia F. da; Santos, William de S.; Caldas, Linda V.E., E-mail: maysadecastro@gmail.com, E-mail: lpneves@ipen.br, E-mail: na.fiorini@gmail.com, E-mail: wssantos@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    For performing dosimetry in computed tomography beams (CT), use is made of a pencil-type ionization chamber, since this has a uniform response to this type of beam. The common commercial chambers in Brazil have a sensitive volume length of 10 cm. Several studies of prototypes of this type of ionization chamber have been conducted, using different materials and geometric configurations, in the Calibration Laboratory Instruments of the Institute of Nuclear and Energy Research (LCI) and these showed results within internationally acceptable limits. These ion chambers of 10 cm are widely used nowadays, however studies have revealed that they have underestimated the dose values. In order to solve this problem, we developed a chamber with sensitive volume length of 30 cm. As these are not yet very common and no study has yet been performed on LCI conditions on their behavior, is important that the characteristics of these dosemeters are known, and the influence of its various components. For your review, we will use the Monte Carlo code Penelope, freely distributed by the IAEA. This method has revealed results consistent with other codes. The results for this new prototype can be used in dosimetry of the CT of the hospitals and calibration laboratories as the LCI.

  5. ERI and initial clinical experience with dosimetry check, a commercial software for dosimetry in vivo volumetric; ERI y experiencia clinica inicial con dosimetry check, un software comercial para dosimetria in vivo volumetrica

    Energy Technology Data Exchange (ETDEWEB)

    Pujades Claumarchirant, M. C.; Gimeno Olmos, J.; Garcia Martinez, T.; Carmona Meseguer, V.; Lliso Valverde, F.; Palomo Llinares, R.; Ballester Pallares, F.; Perez Calatayud, J.

    2013-07-01

    The objective of this work is to study the differences in dose at a point of reference between the result of calculation of dose and the planning system to establish a level of uncertainty of the system. In addition, evaluates its use in clinical routine and presents results obtained with the first patients. (Author)

  6. Analysis on the allocation of administrative dose control of personal dosimetry in the HU Ramon y Cajal in Madrid; Analisis sobre la asignacion de dosis adminsitrativas en el control de dosimetria personal en el Hu Ramon y Cajal de Madrid

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, K.; Prieto, D.; Alonso, L.; Sastre, J. M.; Ferrer, N.; Arranz, L.

    2011-07-01

    Continuing education programs and information and personal follow through written and verbal notifications implemented in the hospital have allowed to know the causes of non-delivery of the dosimeter, reduce the percentage of administrative dose assignment and achieve a more effective dosimetric control.

  7. Advances in development of young-pediatric anthropometric and anthropomorphic head and neck phantoms for dosimetry; Avancos no desenvolvimento de fantomas antropomorfico e antropometrico de cabeca e pescoco infanto-juvenil para dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Larissa; Campos, Tarcisio P.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares]. E-mail: thompson@nuclear.ufmg.br; campos@nuclear.ufmg.br

    2005-07-01

    The neck malign cancer in pediatric population differs significantly than adult cancer. The pediatric primary malign tumors result in the neck and head fence 5% . The malign cervical tumors, generally, are rabdomyossarcoms and lymphomas. The least frequent malign cancer includes metastasis, scammous cells and thyroid cancer. The larynx cancer treatment is surgery, preferentially. However, lesions with little infiltration, that do not compromise the vocals cords mobile, do not infiltrate cartilage, and do not compromise neither the anterior comissure neither the arytenoid, can be controlled with exclusive radiotherapy. The traditional dose for sub-clinical disease in larynx cancer, neck and head region, has been 50 to 60 Gy to standard fraction of 2 Gy/day, five times for week. When the treatment is consummated with exclusive radiotherapy in primary tumor. The dose must be higher, diversifying from 66 (for small tumors T1) to 70 Gy (for higher tumors, that T2 or T3). Phantoms are simulators utilized for dose prediction in patient simulating radiation interactions with matter. Also it is applied for radio diagnosis equipment calibration and quality control of medical image. Many kind of phantoms are developed, handmade and commercialized, with matters and forms most varied, holding distinct purpose, in senses of establishing double check parameters for reducing planning and calibration errors. This study addresses the development of a object for simulating young-pediatric anthropometric and anthropomorphic head and neck, called phantom, for dosimetric studies. The methodology will be based on the preparation of a phantom respecting the anatomic standards and its tissue equivalent composition. The hope is that phantom can be used in the scientific researches of radiation protocols applied to young-pediatric patient. (author)

  8. Study of technical and economic feasibility of using a portal dosimetry system for quality control of linear accelerators; Estudio de viabilidad tecnica y economica del uso de un sistema de dosimetria portal para el control de calidad de aceleradores lineales

    Energy Technology Data Exchange (ETDEWEB)

    Fax, X.; Piro, N.; Sanchez, N.; Toribio, I.; Hermida, M.; Seioane, A.; Saez, J.; Beltran, M.

    2011-07-01

    We have studied the feasibility of Varian portal vision system AS500-II, dosimetry calibration mode, as a substitute for radiochromic plates in quality control tests that required the use of such film. Over a period of two months have been analyzed both the dosimetric characteristics of the system and the mechanical positioning. In addition there has been a financial estimate of annual savings that would result from replacing the radiochromic film by the portal system in a multi-energy accelerator.

  9. Dosimetric evaluation of the Fricke gel dosimeter using the spectrophotometric technique for application in electron and neutron dosimetry; Avaliacao dosimetrica da solucao Fricke gel usando a tecnica de espectrofotometria para aplicacao na dosimetria de eletrons e neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Mangueira, Thyago Fressatti [Instituto de Pesquisas Energeticas e Nucleares (GMR/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Metrologia das Radiacoes

    2011-07-01

    The main dosimetric characteristics of the Fricke Xylenol Gel (FXG) solution were established for further application in the measurement of dose distribution of clinical electron fields. The dose-response curves of the FXG in a thermal neutron field were also evaluated for application in Boron Neutron Capture Therapy (BNCT) and industrial electron fields. The standard reading technique was the spectrophotometry. For clinical fields the intra and inter-batch reproducibility of FXG solution are better than 1.4% and 5.1%, respectively. The optical response presents a linear behavior for doses ranging from 0.2 to 40 Gy independently of the electron energy and the dose rate in the studied ranges. Due to the effects of the FXG natural oxidation, the optimum elapsed time between FXG preparation and irradiation was established as 24h. The behavior of the dose-response curve does not change the obtained absorbance values relative to the non-irradiated dosimeter response during the studied period. The dose-response curve to industrial electron beam presented an exponential decreasing behavior. The optical response to thermal neutrons beam presented a linear behavior for the studied dose range. According to the obtained results to the different radiation fields studied it was not observed changes in the wavelength of the typical bands of the absorption spectrum radiation induced. Additional tests were performed with FXG solution to verify the viability and application of FXG dosimetry on intracavitary brachytherapy using digital photographic imaging. The excellent performance of the FXG dosimeter indicates that this dosimeter may be applied to tri-dimensional dose evaluation in radiotherapy treatments using electrons and neutron beams. (author)

  10. Responses of different dosemeters in beta dosimetry of {sup 106}Ru/{sup 106}Rh ophthalmic applicators;Respostas de diferentes dosimetros termoluminescentes na dosimetria beta de aplicadores oftalmicos de {sup 106}Ru/{sup 106}Rh

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, D.F.P.; Daros, K.A.C.; Segreto, R.A.; Medeiros, R.B. [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil)

    2009-07-01

    This work presents the TL response of three kinds of dosimeters from different manufacturing characteristics under irradiation of 106 Ru / 106 Rh sealed sources used in ophthalmic brachytherapy. They are: Ca SO{sub 4}:Dy + teflon (D- Ca SO{sub 4}:Dy -0,4), LiF:Mg, Ti (TLD-100) and Ca SO{sub 4}:Dy (TLD-900). Some of reports accepted by scientific community (NCS report 14 e ICRU report 72) as reference in the quality control of beta applicators dosimetry recommend that the absorbed dose standard uncertainties can be kept below 20%. The TLD Ca SO{sub 4}:Dy + teflon presented proper sensibility and high precision comparing with the others. Considering the similar dimensions of ophthalmic tumors and aside critical structures it is relevant to reduce undesirable effects due to the irradiation of these structures. Therefore, the quality control in the beta dosimetry using this kind of source is a constant challenge. (author)

  11. 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)

  12. In vivo dosimetry HDR brachytherapy prostate with source CO-60: Results of measures in a point urethra; Dosimetria in vivo en braquiterapia HDR de prostate con fuente de CO-60: Resultados de medidas en un punto de uretra

    Energy Technology Data Exchange (ETDEWEB)

    Latorre, D.; Fernandez, J.; Rivero, G.; Crelgo, D.; Gonzalez, J. M.; Sanchez, P.; Villace, A.; Sanchez, E.; Arroyo, M. A.; Garcia, E.; Trabanco, E.

    2015-07-01

    In this study we present and analyze the results of the in vivo dosimetry made a point of urethra with a group of 30 patients treated with brachytherapy prostate high rate with Co-60 source. Taking into account the uncertainties, the results and integration, globally evaluate this system DIV. This DIV system, due to its ease of calibration and use, and provides a relatively simple integration way to avoid serious errors in administering treatment. (Author)

  13. 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)

  14. Determination of radiation dose to patient by biological dosimetry in interventional radiological procedures; Estimacion de la dosis de radiacion a paciente mediante dosimetria biologica en exploraciones complejas de radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Serna Berna, A.; Alcaraz, M.; Armero, D.; Navarro, J. L.; Morant, J. J.; Canteras, M.

    2006-07-01

    Interventional radiology is substituting complex surgical procedures. The requirements of high quality images and long fluoroscopy exposure times gives rise to high levels of radiation doses to patients. This topic is increasingly becoming of high concern. The purpose of this work was to evaluate the micronucleus assay (MN) in lymphocytes for the determination of the dose delivered to 15 patients who underwent interventional radiological procedures. The determination of a dose to patients supposing uniform irradiation was done with a dose-effect calibration curve previously determined for 120 keV X-rays. due to the low level of MN rate compared with background we used a bayesian approach to obtain the net MN counting rate, resulting and average counting rate of 3,2{+-}2,5 MN/500 bi nucleated cell. The group of coronariography patients resulted in higher MN rate 5,1 MN/500 BC vs 2,6 for the rest of patients. Average equivalent uniform dose for the total group of patients was 6,5{+-}2,6 cGy, while for the coronariography group was 8,8 {+-} 4,6 cGy. In conclusion, interventional radiology procedures deliver significant doses to patients and the MN assay as biological dosimeter is a good too to evaluate this range to doses. (Author)

  15. Low temperature dosimetry in LiF: Mg, Cu, P and CaSO{sub 4}: Dy doped crystals; Dosimetria de baja temperatura en cristales dopados LiF: Mg, Cu, P y CaSO{sub 4}: Dy

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E.; Ramos B, S.; Negron M, A.; Rivera, T. [Instituto de Ciencias Nucleares, UNAM, A.P. 70-543, 04510 Mexico D.F. (Mexico)

    2000-07-01

    It is presented a behavior study of LiF solid dosemeters doped with Mg, Cu and P also polycrystalline samples of CaSO{sub 4} with Dy sinterized in laboratory, both of them were subjected at low temperature. In order to analyse linear behavior to the dose of these dosemeters, it was used thermoluminescence. These materials were exposed to gamma radiation coming from a Co-60 source. The samples were irradiated at dose rates 1.08 {+-} 0.01 Gy/min at liquid nitrogen temperature (LNT) and also the response of dosemeters are compared at ambient temperature and LNT. (Author)

  16. X-ray dosimetry of low energy using ZrO{sub 2} in Mammography; Dosimetria de rayos X de baja energia usando ZrO{sub 2} en mastografia

    Energy Technology Data Exchange (ETDEWEB)

    Palacios P, L.L.; Rivera M, T.; Ortiz C, H.; Guzman, G. [CICATA, IPN, Av. Legaria 694, 11500 Mexico D.F. (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Garcia H, M. [IIM, UNAM, 04510 Mexico D.F. (Mexico)

    2008-07-01

    This work reports the experimental results of the thermoluminescent dosemeters (DTL) of nano particles of zirconium dioxide (ZrO{sub 2}), prepared by the precipitation for X rays method of low energy that are used in mammography equipment. It is observed that the response of the TL curve for X rays of low energy coincides with the TL curve of ZrO{sub 2} reported for conventional X rays. This curve presents two peaks, at 160 and 270 C respectively, being that of more intensity the second peak. (Author)

  17. Importance of the effective atomic number (Z{sub eff}) of TL materials for radiation dosimetry in clinical applications; Importancia del numero atomico efectivo (Z{sub eff}) de materiales TL para dosimetria de la radiacion en aplicaciones clinicas

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P.R. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: pgm@nuclear.inin.mx

    2008-07-01

    The electric power generation, it has been one of the radiation applications of bigger weight, mainly in developed countries. Another sector of more impact is without a doubt that of the medicine. However, for a sure operation with radiations, those international organisms of radiological safety, exist every time more precise detection systems. The thermoluminescent dosimetry is one of the more reliable methods for this purpose, for that several groups of investigators from different parts of the world, they have guided its investigations in the development of new TL materials. However, to avoid underestimate or overestimation of the measured dose with the use of these materials, it should take into account it effective atomic number (Z{sub eff}) it is well known that some TL materials considered as equivalent to the tissue, presents smaller TL intensity when being irradiated with low energy photons, while the TL material known as not equivalent to the tissue, they present the supra sensitivity effect for this radiation type. Nowadays, the estimate of the Z{sub eff} has not been clear, in this work the Z{sub eff} is determined by means of the traditional methods and an own method is presented for its determination. The results of the TL signal of different materials, when being irradiated with photons of effective energy between 24 keV and 1.25 MeV and their relationship with their calculated Z{sub eff} are also presented. (Author)

  18. 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)

  19. 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)

  20. 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)

  1. 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.

  2. Avaliação espectroscópica de corantes orgânicos submetidos a raios-X: aplicação em dosimetria de radiação ionizante

    OpenAIRE

    BENEVIDES, Clayton Augusto

    2015-01-01

    Esta tese teve o objetivo de entender como ocorre a degradação de determinados corantes orgânicos fluorescentes quando irradiados e avaliar quantitativamente esta degradação. Os experimentos foram feitos utilizando uma concentração específica para os dois corantes: Rodamina 6G e Fluoresceína em gel de agarose e NaCl. NaCl foi utilizado a fim aumentar a taxa de degradação dos fluoróforos. Uma vez estabelecidos os sistemas químicos, as irradiações foram executadas sob um feixe ...

  3. Comparison of radiation doses obtained for radiation monitoring of controlled areas with radiation doses obtained for personnel dosimetry in radiodiagnosis centers; Comparacion de dosis obtenidas por monitoreo en areas controladas con las obtenidas por dosimetria personal en centros de radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Lescano, Roberto; Caspani, Carlos [Ministerio de Salud y Medio Ambiente, Santa Fe (Argentina). Direccion General de Auditoria Medica. Radiofisica Sanitaria]|[Universidad Nacional del Litoral, Santa Fe (Argentina). Faculdad de Bioquimica y Ciencias Biologicas. Escuela Superior de Sanidad

    2001-07-01

    In this paper we propose to search an indicator that shows, at an objective way, the quality of the radioprotection actions. The method is about to determine doses, measured in the work area, connecting them with the workload, and finally get the dose for the center. Them we make a comparison with the personal film dosimetry data. We discuss the final results, evaluating the radioprotection conditions in daily work. (author)

  4. 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)

  5. Determination of the chemical yield on the Fricke dosimetry for {sup 192}Ir sources used in brachytherapy; Determinacao do rendimento quimico na dosimetria Fricke para fontes de {sup 192}Ir usadas em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    David, M.G.; Albuquerque, M.A.G.; Almeida, C.E. de, E-mail: marianogd08@gmail.com [Universidade do Estado do Rio de Janeiro (LCR/UERJ), Rio de Janeiro, RJ (Brazil). Lab. de Ciencias Radiologicas; Salata, C. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Rosado, P.H. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    With the aim of developing a primary standard for the absorbed dose to water, for the {sup 192}Ir sources used in high dose rate brachytherapy, this work focuses on the determination of the chemical yield, G(Fe{sup +3}), using Fricke dosimetry, for the energy of those sources . The G(Fe{sup +3}) were determined the for three qualities of x-ray beams (150, 250 and 300 kV ) and for {sup 60}Co energy. The G(Fe{sup +3}) value for the average energy of {sup 192}Ir was obtained by linear fit, the found value was 1,555 ± 0,015 μmol/J. (author)

  6. 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)

  7. A Test of Reliability of the Personnel Dosimetry Services Authorized by CSN using Photon Beams; Control de los servicios de dosimetria personal autorizados por el CSN, usando haces de fotones

    Energy Technology Data Exchange (ETDEWEB)

    Brosed, A.; Delgado, A.; Granados, C. E.; Lopez Ortiz, G.

    1987-07-01

    In 1987 the Consejo de Seguridad Nuclear (CSN) had eight Personnel Dosimetry Services (PDS) authorized to asses the equivalent doses to the spanish occupationally exposed workers, by means of the readings from the dosemeters wear by them. An audit was carried on the PDS on behalf of CSN under the control of CIEMAT. Batches of dosemeters from each one of the PDS were irradiated to dose equivalent values which were well established by CIEMAT but kept hidden from the PDS. By comparing the true values with those obtained by the PDS, it was possible to evaluate the Services according to the analysis of the quantity Q= I B I -I- S where B is the average of the individual deviations between the dosemeters belonging to the same group and the true value as established by CIEMAT, whereas S is the standard deviation of the values inside of this same group. The results of the evaluation, which was made using the new ICRU quantities for personnel monitoring, are presented. (Author) 8 refs.

  8. Evaluation of thermoluminescent dosimeters using water equivalent phantoms for application in clinical electrons beams dosimetry; Avaliacao de dosimetros termoluminescentes empregando objetos simuladores equivalentes a agua para aplicacao na dosimetria de feixes clinicos de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, Amanda

    2010-07-01

    The dosimetry in Radiotherapy provides the calibration of the radiation beam as well as the quality control of the dose in the clinical routine. Its main objective is to determine with greater accuracy the dose absorbed by the tumor. This study aimed to evaluate the behavior of three thermoluminescent dosimeters for the clinical electron beam dosimetry. The performance of the calcium sulfate detector doped with dysprosium (CaSO{sub 4}: Dy) produced by IPEN was compared with two dosimeters commercially available by Harshaw. Both are named TLD-100, however they differ in their dimensions. The dosimeters were evaluated using water, solid water (RMI-457) and PMMA phantoms in different exposure fields for 4, 6, 9, 12 and 16 MeV electron beam energies. It was also performed measurements in photon beams of 6 and 15 MV (2 and 5 MeV) only for comparison. The dose-response curves were obtained for the {sup 60}Co gamma radiation in air and under conditions of electronic equilibrium, both for clinical beam of photons and electrons in maximum dose depths. The sensitivity, reproducibility, intrinsic efficiency and energy dependence response of dosimeters were studied. The CaSO{sub 4}: Dy showed the same behavior of TLD-100, demonstrating only an advantage in the sensitivity to the beams and radiation doses studied. Thus, the dosimeter produced by IPEN can be considered a new alternative for dosimetry in Radiotherapy departments. (author)

  9. Response different of MAGIC-f gel in clinical electron and photon beams dosimetry;Estabilidade de resposta do gel MAGIC-f na dosimetria de feixes clinicos: eletrons e fotons

    Energy Technology Data Exchange (ETDEWEB)

    Pianoschi, Thatiane; Marques, Tatiana; Goncalves, Leandro; Alva, Mirko; Baffa, Oswaldo [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Dept. de Fisica e Matematica; Nicolucci, Patricia [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Centro de Instrumentacao, Dosimetria e Radioprotecao

    2009-07-01

    The dosimetry with polymeric gel has been widely used in the clinic routines of the quality control in Radiotherapy since it allows one to verify volumetric dose distributions. Due to its capacity in detecting very high dose gradients with high spatial resolution, the MAGIC-f dosimeter is shown as an accurate tool in the 3D dosimetry aspects. Although the amount of information on gel dosimetry for photon beams is large in the literature, simple properties of its response to electron beams are not set yet. In this work we present experimental results of dose deposited in MAGIC-f gel for 9 and 15 MeV electron beams and 6 and 10 MV photon beams. The analysis of its stability for these clinical beams was set by the comparison between the signal curves and the dose for each energy. The DDP curves showed a difference less than 4% to the 9 MeV beam. The MAGIC-f gel is shown as an accurate dosimeter for clinical electron beams, being equivalent to tissue composition, linearity and stability in the response. (author)

  10. In vivo dosimetry with semiconductor and thermoluminescent detectors applied to head and neck cancer treatment; Dosimetria in vivo com uso de detectores semicondutores e termoluminescentes aplicada ao tratamento de cancer de cabeca e pescoco

    Energy Technology Data Exchange (ETDEWEB)

    Viegas, Claudio Castelo Branco

    2003-03-15

    In vivo dosimetry in radiotherapy, i. e, the assessment of the doses received by patients during their treatments, permits a verification of the therapy quality. A routine of in vivo dosimetry is, undoubtedly, a direct benefit for the patient. Unfortunately, in Brazil and in Latin America this procedure is still a privilege for only a few patients. This routine is of common application only in developed countries. The aim of this work is to show the viability and implementation of a routine in vivo dosimetry, using diodes semiconductors and thermoluminescent dosimeters (TLD), at the radiotherapy section of the National Institute of Cancer in Brazil, in the case of head and neck cancer treatment. In order to reach that aim, the characteristics of the response of diodes ISORAD-p and LiF:Mg;Ti (TLD-100) thermoluminescent detectors in powder form were determined. The performance of those detectors for in vivo dosimetry was tested using an RANDO Alderson anthropomorfic phantom and, once their adequacy proved for the kind of measurements proposed, they were used for dose assessment in the case of tumour treatments in the head and neck regions, for Cobalt-60 irradiations. (author)

  11. 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)

  12. Primary and scattering contributions to beta scaled dose point kernels by means of Monte Carlo simulations; Contribuicoes primaria e espalhada para dosimetria beta calculadas pelo dose point kernels empregando simulacoes pelo Metodo Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Valente, Mauro [CONICET - Consejo Nacional de Investigaciones Cientificas y Tecnicas de La Republica Argentina (Conicet), Buenos Aires, AR (Brazil); Botta, Francesca; Pedroli, Guido [European Institute of Oncology, Milan (Italy). Medical Physics Department; Perez, Pedro, E-mail: valente@famaf.unc.edu.ar [Universidad Nacional de Cordoba, Cordoba (Argentina). Fac. de Matematica, Astronomia y Fisica (FaMAF)

    2012-07-01

    Beta-emitters have proved to be appropriate for radioimmunotherapy. The dosimetric characterization of each radionuclide has to be carefully investigated. One usual and practical dosimetric approach is the calculation of dose distribution from a unit point source emitting particles according to any radionuclide of interest, which is known as dose point kernel. Absorbed dose distributions are due to primary and radiation scattering contributions. This work presented a method capable of performing dose distributions for nuclear medicine dosimetry by means of Monte Carlo methods. Dedicated subroutines have been developed in order to separately compute primary and scattering contributions to the total absorbed dose, performing particle transport up to 1 keV or least. Preliminarily, the suitability of the calculation method has been satisfactory, being tested for monoenergetic sources, and it was further applied to the characterization of different beta-minus radionuclides of nuclear medicine interests for radioimmunotherapy. (author)

  13. Dose absorbed in adults and children thyroid due to the I{sup 123} using the dosimetry MIRD and Marinelli; Dosis absorbida en tiroides de adultos y ninos debido al I{sup 123} utilizando las dosimetrias MIRD y Marinelli

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, M.; Castillo, C.; Cabrera, C.; Sarachaga, R.; Castaneda, J. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru); Diaz, E., E-mail: marvva@hotmail.com [Universidade Federal do Rio Grande do Sul, Av. Paulo Gamma 110, Bairro Farropilhas, Porto Alegre, RS 90040-060 (Brazil)

    2014-08-15

    Using the dosimetry MIRD, and representation Cristy-Eckerman in the thyroid gland and organs of their bio-kinetics when I{sup 123} (Iodine) is used, the study demonstrates that the absorbed dose by the gland of an adult, children, and newly born, is their auto-dose, independent of the compartments number of their bio-kinetics. The dosimetric contributions of the organs of their bio-kinetics are insignificant. Their results are not significantly different to those obtained by the formalism MARINELLI (auto-dose) when it uses a sphere like glandular representation. In consequence, the kinetic model corresponding to the glandular representation decreases to a compartment, where the gland can also be represented like a sphere. (Author)

  14. Accounting of costs in a service of physical health. Relative units of value in dosimetry clinic in teletherapy; Contabilidad de costes en un servicio de fisica medica. Unidades relativas de valor en dosimetria clinica en teleterapia

    Energy Technology Data Exchange (ETDEWEB)

    Font Gomez, J. A.; Gandia Martinez, A.; Jimenez Albericio, F. J.; Andres Redondon, M. M.; Mengual Gil, M. A.

    2013-07-01

    A single - although laborious - start in the economic and clinical management of our units can be come to the knowledge of the time invested in the tasks functional, having to differentiate them, name them and even encrypt them. The time spent in performing the tasks multiplied by the annual number of these will indicate the resources necessary to achieve our objectives. In addition, pooling the values of times that members of the Unit provide analysed inter-workers dispersal, their causes and possible solutions. The establishment of relative units of value in any process benefits all workers involved in the process since it allows to know the dispersion of the times that each person employed in the development of the tasks. (Author)

  15. Whole body dosimetry for treatment individualized neuroblastoma with {sup 1}31I-MIBG; Dosimetria de cuerpo entero para el tratamiento individualizado del neuroblastoma con {sup 1}31I-MIBG

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer Gracia, C.; Luquero Llopis, N.; Sanchez Munoz, F.; Plaza Aparicio, R.; Huerga Cabrerizo, C.; Corredoira Silva, E.; Serrada Hierro, A.

    2013-07-01

    It according to in this study, that in therapy with {sup 1}31I-MIBG for the treatment of neuroblastoma, it can prescribe and manage dose whole body accurately, allowing individualized treatments and major activities that in the treatments based on a fixed activity according to weight management. (Author)

  16. 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)

  17. 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)

  18. 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)

  19. Activities developed by the biological dosimetry laboratory of the Autoridad Regulatoria Nuclear - ARN of Argentina; Actividades desarrolladas por el laboratorio de dosimetria biologica de la Autoridad Regulatoria Nuclear de Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Radl, A.; Sapienza, C.E.; Taja, M.R.; Bubniak, R.; Deminge, M.; Di Giorgio, M., E-mail: csapienza@arn.gob.ar [Autoridad Regulatoria Nuclear (ARN), Buenos Aires (Argentina)

    2013-07-01

    Biological dosimetry (DB) allows to estimate doses absorbed in individuals exposed to ionizing radiation through the quantification of stable and unstable chromosome aberrations (SCA and UCA). The frequency of these aberrations is referred to a calibration dose response curve (in vitro) to determine the doses of the individual to the whole body. The DB is a necessary support for programs of national radiation protection and response systems in nuclear or radiological emergencies in the event of accidental or incidental, single overexposure or large scale. In this context the Laboratory of Dosimetry Biological (LDB) of the Authority Regulatory Nuclear (ARN) Argentina develops and applies different dosimeters cytogenetic from four decades ago. These dosimeters provide a fact more within the whole of the information necessary for an accidental, complementing the physical and clinical dosimetry exposure assessment. The most widely used in the DB biodosimetric method is the quantification of SCA (dicentrics and rings Central) from a sample of venous blood. The LDB is accredited for the trial, under rules IRAM 301: 2005 (ISO / IEC 17025: 2005) and ISO 19238:2004. Test applies to the immediate dosimetry evaluation of acute exposures, all or a large part of the body in the range 0,1-5 Gy. In this context the LDB is part of the Latin American network of DB (LBDNet), BioDoseNet-who and response system in radiological emergencies and nuclear IAEA-RANET, being enabled to summon the LBDNet if necessary.

  20. 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)

  1. CM2 allocation model proposed by rate in area dosimetry research laboratories unsealed sources; CM2 propuesta de modelo de asignacion de dosis mediante dosimetria de area en laboratorios de investigacion de fuestes no encapsuladas

    Energy Technology Data Exchange (ETDEWEB)

    Raya Hidalgo, P.; Galvez Delgado, M.; Vaquero Abellan, M.

    2013-07-01

    The condition of workers exposed to ionizing radiation in categories A and B, required to be subject to a system of dosimetry monitoring that ensures that received doses are compatible with their classification. The objective of this project is make a proposal for the classification of the laboratories of research and teaching staff to the radiation facilities (IRAs) of non-encapsulated sources and establish a new dose mapping procedure staff. (Author)

  2. Optically stimulated luminescence dating at Rose Cottage Cave

    CSIR Research Space (South Africa)

    Pienaar, M

    2008-01-01

    Full Text Available Six Optically stimulated luminescence (OSL) dates are compared with stratigraphically associated C-14 dates from Rose Cottage Cave. The OSL dates overlap the accepted C-14 chronology except for one sample that overestimates the expected age...

  3. Soil development rates from an optically stimulated luminescence-dated beach ridge sequence in Northern Jutland, Denmark

    DEFF Research Database (Denmark)

    Nielsen, Asger Habekost; Elberling, Bo; Pejrup, Morten

    2010-01-01

    of each pedon and soil stratum was measured by optically stimulated luminescence (OSL) dating and used to estimate soil development rates. Soils were divided into five groups from Typic Haplorthods and Entic Alorthods with a mean OSL age of 29659294 yr to Typic Quartzipsamments with a mean OSL age...

  4. Measuring modulated luminescence using non-modulated stimulation: Ramping the sample period

    DEFF Research Database (Denmark)

    Poolton, N.R.J.; Bøtter-Jensen, L.; Andersen, C.E.;

    2003-01-01

    . Directly analogous results to LM-OSL can, however, be achieved with non-modulated excitation sources, by ramping the sample period (RSP) of luminescence detection. RSP-OSL has the distinct advantage over LM-OSL in that, since the excitation remains at full power, data accumulation times (that can...

  5. Luminescence property of volcanic quartz and the use of red isothermal TL for dating tephras

    DEFF Research Database (Denmark)

    Tsukamoto, S.; Murray, A.S.; Huot, S.

    2007-01-01

    An optically stimulated luminescence (OSL) age obtained from a Japanese tephra using quartz phenocrysts severely underestimated the known age. The characteristics of the OSL signals were investigated in order to understand the cause of the underestimation; the main OSL component of volcanic quartz...

  6. 多片再生法在海洋沉积物测年中的应用%OSL dating of marine sediments using multiple-aliquot regeneration-dose method

    Institute of Scientific and Technical Information of China (English)

    陈强; 业渝光; 刁少波

    2011-01-01

    本文用光释光多片再生法对我国黄海海域沉积物样品进行了测年.按不同深度选取同一柱状样四个取样点,采用4-11 μm的细颗粒进行释光年代测量.为评估测年结果的可靠性,将释光测量结果与该柱状样相近层位样品的AMS 14C测年结果比对,发现在AMS 14C测年的灵敏度范围内,两者结果吻合良好.

  7. Luminescence sensitivity changes in quartz as a result of annealing

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Agersnap Larsen, N.; Mejdahl, V.

    1995-01-01

    Retrospective dosimetry using optically stimulated luminescence (OSL) on quartz extracted from (for example) bricks needs to account for strong OSL sensitivity changes that are known to occur depending on the previous thermal treatment of the sample. Non-heated quartz exhibits OSL orders of magni......Retrospective dosimetry using optically stimulated luminescence (OSL) on quartz extracted from (for example) bricks needs to account for strong OSL sensitivity changes that are known to occur depending on the previous thermal treatment of the sample. Non-heated quartz exhibits OSL orders...... of magnitude less per unit radiation than that for heated material. The reason these temperature-induced sensitivity changes occur in quartz is presently not well understood. This phenomenon is also seen in the related area of luminescence dating in which sedimentary quartz and quartz from heated...

  8. SEMICONDUCTOR PHYSICS Dose-rate dependence of optically stimulated luminescence signal

    Science.gov (United States)

    Pingqiang, Wei; Zhaoyang, Chen; Yanwei, Fan; Yurun, Sun; Yun, Zhao

    2010-10-01

    Optically stimulated luminescence (OSL) is the luminescence emitted from a semiconductor during its exposure to light. The OSL intensity is a function of the total dose absorbed by the sample. The dose-rate dependence of the OSL signal of the semiconductor CaS doped Ce and Sm was studied by numerical simulation and experiments. Based on a one-trap/one-center model, the whole OSL process was represented by a series of differential equations. The dose-rate properties of the materials were acquired theoretically by solving the equations. Good coherence was achieved between numerical simulation and experiments, both of which showed that the OSL signal was independent of dose rate. This result validates that when using OSL as a dosimetry technique, the dose-rate effect can be neglected.

  9. Dose response of hydrazine - Deproteinated tooth enamel under blue light stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Yuece, Ulkue Rabia, E-mail: ulkuyuce@hotmail.co [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Meric, Niyazi, E-mail: meric@ankara.edu.t [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Atakol, Orhan, E-mail: atakol@science.ankara.edu.t [Ankara University, Science Faculty, Department of Chemistry, 06100, Tandogan - Ankara (Turkey); Yasar, Fusun, E-mail: ab121310@adalet.gov.t [Council of Forensic Medicine, Ankara Branch, Ankara (Turkey)

    2010-08-15

    The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.

  10. Search for stable energy levels in materials exhibiting strong anomalous fading: The case of apatites

    Energy Technology Data Exchange (ETDEWEB)

    Polymeris, George S., E-mail: polymers@auth.gr [Laboratory of Radiation Applications and Archaeological Dating, Department of Archaeometry and Physicochemical Measurements, ‘Athena’—Research and Innovation Center in Information, Communication and Knowledge Technologies, Kimmeria University Campus, GR-67100 Xanthi (Greece); Solid State Physics Section, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Giannoulatou, Valeria; Sfampa, Ioanna K. [Nuclear Physics Laboratory, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Tsirliganis, Nestor C. [Laboratory of Radiation Applications and Archaeological Dating, Department of Archaeometry and Physicochemical Measurements, ‘Athena’—Research and Innovation Center in Information, Communication and Knowledge Technologies, Kimmeria University Campus, GR-67100 Xanthi (Greece); Kitis, George [Nuclear Physics Laboratory, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2014-09-15

    The thermally assisted OSL signal resulting from very deep traps was studied in the case of three fluorapatite samples, one chlorapatite as well as one collophanite cryptocrystalline carbonite phosphorite sample of various origins. Intense thermally assisted OSL signal was monitored while stimulating at 200 °C in all samples subjected to the present study, indicating the prevalence of the existence of these very deep traps. Anomalo