WorldWideScience

Sample records for thermoluminescent dosimetry verificacion

  1. THERMOLUMINESCENT DOSIMETRY

    Energy Technology Data Exchange (ETDEWEB)

    Malsky, Stanley J.; Amato, Charles G.; Roswit, Bernard

    1963-06-15

    The performance of CaF/sub 2/: Mn and LiF as thermoluminescent in vivo dosimeters is studied. The facility with which this type of dosimeter can be inserted into the body is discussed. The dosimeter is inserted into the body by trocar or catheter techniques and exposed to radiation; it is then removed and heated, and the thermoluminescence is measured and used as an indication of the absorbed dose. (T.F.H.)

  2. Thermoluminescence albedo-neutron dosimetry

    International Nuclear Information System (INIS)

    Strand, T.; Storruste, A.

    1986-10-01

    The report discusses neutron detection with respect to dosimetry and compares different thermoluminescent dosimetry materials for neutron dosimetry. Construction and calibration of a thermoluminescence albedo neutron dosemeter, developed by the authors, is described

  3. Thermoluminescence in medical dosimetry

    International Nuclear Information System (INIS)

    Rivera, T.

    2011-10-01

    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)

  4. Instrumentation in thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Julius, H.W.

    1986-01-01

    In the performance of a thermoluminescence dosimetry (TLD) system the equipment plays an important role. Crucial parameters of instrumentation in TLD are discussed in some detail. A review is given of equipment available on the market today - with some emphasis on automation - which is partly based on information from industry and others involved in research and development. (author)

  5. Thermo-luminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Reither, M; Schorn, B; Schneider, E

    1981-01-01

    The development of paediatric radiology which began in the late 195O's has been characterised by the need to limit the dose of ionising radiation to which the child is subjected. The aim has been to keep radiation exposure as low as possible by the introduction of suitable techniques and by the development of new methods. It is therefore surprising that studies in dosimetry in the paediaytric age range have only been carried out in recent years. One reason for this may have been the fact that a suitable technique of measurement was not available at the time. The introduction of solid state dosimetry based on thermo-luminescence, first into radiotherapy (1968) and subsequently into radiodiagnosis, has made it possible to abandon the previously widely used ionisation chamber. The purpose of the present paper is to indicate the suitability of this form of dose measurement for paediatric radiological purposes and to stimulate its application in this field.

  6. Thermoluminescence dosimetry environmental monitoring system

    International Nuclear Information System (INIS)

    Bortoluzzi, S.

    1989-01-01

    In this report, characteristics and performances of an environmental monitoring system with thermoluminescence dosimetry are presented. Most of the work deals with the main physical parameters necessary for measurements of ambiental dose. At the end of this report some of level doses in the environment around the site of the ENEA Center of Energy Research Salluggia (Italy) are illustrated

  7. Image in nuclear dosimetry using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Guinsburg, G.; Matsuoka, M.; Watanabe, S.

    1987-01-01

    A low cost methodology to produce images of internal sick organs by radioisotopic intake, is presented. Dosimetries of thermoluminescent material and Teflon (ratio:50%) in bidimensional matrix shape are used with a Pb collimator. This collimator-bidimensional matrix system was tested ''in vivo'' and in thyroid phantoms using 99m Tc. A comparative evaluation between this method and the scintigraphy one is presented. (M.A.C.) [pt

  8. TELDE thermoluminescent dosimetry system

    International Nuclear Information System (INIS)

    Shvarts, K.K.; Nemiro, E.A.; Bichev, V.R.; Gotlib, V.I.; Grant, Z.A.; Grube, M.M.; Gubatova, D.J.

    1981-01-01

    The TELDE dosimetric set designed for measurement of x- and γ- rays doses with energy more than 10 keV is described. The set consists of thermoluminescent detectors from LiF (Ca, Mg, Ti). The detectors are polycrystalline pellets with diameter 3.5+-0.3 mm and thickness 2+-0.2 mm. In the thermoluminescence detectors both the peak and integral measurement methods are realized. Apart from this the TELDE set comprises the electron unit for the pre-irradiation thermal treatment of detectors, special bones for detectors storage and transportation, devices for their package in polyethelene film and containers to wear the detectors. The TELDE set allows to perform measurements on people or animals in radiobiological experiments as well as in water, solid or porous phantoms [ru

  9. Thermoluminescent measurement in space radiation dosimetry

    International Nuclear Information System (INIS)

    Chen Mei; Qi Zhangnian; Li Xianggao; Huang Zengxin; Jia Xianghong; Wang Genliang

    1999-01-01

    The author introduced the space radiation environment and the application of thermoluminescent measurement in space radiation dosimetry. Space ionization radiation is charged particles radiation. Space radiation dosimetry was developed for protecting astronauts against space radiation. Thermoluminescent measurement is an excellent method used in the spaceship cabin. Also the authors mentioned the recent works here

  10. Recent research into thermoluminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, T [National Inst. of Radiological Sciences, Chiba (Japan)

    1979-04-01

    The trend of basic research in thermoluminescent dosimetry (TLD), the results, and developing fields in which it can be applied are reported. This trend is outlined from the viewpoint fields of application, a new trend in TLD readers, the conditions of development of new photogenic substances, and research in the radiation characteristics of photogenic substances (radiosensitivity to particle rays and ultraviolet rays, dose rate dependence, temperature dependence at irradiation, and ..gamma.. ray energy dependence). Utilization of TLD in the medical field for measurement of environmental radiation and as a monitor for workers exposed to radiation is discussed. An international comparison of dose was necessary in order to prove its universal validity.

  11. 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.

  12. Thermoluminescence, a universal tool for dosimetry

    International Nuclear Information System (INIS)

    Barthe, J.

    1999-01-01

    Radio-thermoluminescence is a transient light emission occurring when certain substances, which have been exposed to ionizing radiation, are heated. Under some conditions the quantity of emitted light is proportional to the absorbed dose. This linearity allows thermoluminescence to be used in various fields such as dosimetry, geology and age determination. Dosimeters based on thermoluminescence are passive, they do not require a source of energy and they can sustain high temperatures and high levels of irradiation. Thermoluminescence has been applied for determining the dose absorbed by meteorites and lunar rocks

  13. A microcomputer controlled thermoluminescence dosimetry system

    International Nuclear Information System (INIS)

    Huyskens, C.J.; Kicken, P.J.H.

    1980-01-01

    Using a microcomputer, an automatic thermoluminescence dosimetry system for personal dosimetry and thermoluminescence detector (TLD) research was developed. Process automation, statistical computation and dose calculation are provided by this microcomputer. Recording of measurement data, as well as dose record keeping for radiological workers is carried out with floppy disk. The microcomputer also provides a human/system interface by means of a video display and a printer. The main features of this dosimetry system are its low cost, high degree of flexibility, high degree of automation and the feasibility for use in routine dosimetry as well as in TLD research. The system is in use for personal dosimetry, environmental dosimetry and for TL-research work. Because of its modular set-up several components of the system are in use for other applications, too. The system seems suited for medium sized health physics groups. (author)

  14. Thermoluminescent dosimetry and assessment of personal dose

    International Nuclear Information System (INIS)

    Boas, J.F.; Martin, L.J.; Young, J.G.

    1982-01-01

    Thermoluminescence is discussed in terms of the energy band structure of a crystalline solid and the trapping of charge carriers by point defects. Some general properties of thermoluminescent materials used for dosimetry are outlined, with thermoluminescence of CaSO 4 :Dy being described in detail. The energy response function and the modification of the energy response of a dosimeter by shielding are discussed. The final section covers the connection between exposure, as recorded by a TLD badge, and the absorbed dose to various organs from gamma radiation in a uranium mine; the conversion from absorbed dose to dose equivalent; and uncertainties in assessment of dose equivalent

  15. Dental tissue as a thermoluminescence dosimetry dosimeter

    International Nuclear Information System (INIS)

    Solaimani, F.; Zahmatkesh, M.H.; Akhlaghpoor, Sh.

    2003-01-01

    Background: Thermoluminescence dosimetry is one of the dosimetry procedures used widely as routine and personal dosimeters. In order to extend this kind of dosimeters, dental tissue has been examined and was found promising as a Thermoluminescence Dosimetry dosimeter. Materials and Methods: In this study, 70 health teeth were collected. The only criterion, wich was considered for selection of the teeth, was the healthiness of them regardless of age and gender of the donors. All collected samples were washed and cleaned and milled uniformly. The final powder had a uniform grain size between 100-300 micrometer. The sample was divided into four groups. Group A and B were used for measurement of density and investigation of variation of thermoluminescent characteristics with temperature respectively. Groups C and D were used for investigation of variation of thermoluminescent intensity with dose and fading of this intensity with time. In all cases the results obtained with dental tissue were compared to a standard LiF, thermoluminescence dosimetry dosimeter. Results: It was found that, average density of the dental tissue was 1.570 g/cm 3 , which is comparable to density of LiF, which is 1.612g/cm 3 . It was also concluded that the range of 0-300 d ig C , dental tissue has a simple curve with two specific peaks at 140 and 25 d ig C respectively. The experiment also showed that, the variation of relative intensity versus dose is linear in the range of 0.04-0.1 Gy. The fading rate of dental tissue is higher than LiF but still in the acceptable range (14% per month in compare to 5.2% per month). Conclusion: Dental tissue as a natural dosimeter is comparable with Thermoluminescence Dosimetry and can be used in accidental events with a good approximation

  16. Thermoluminescent dosimetry in veterinary diagnostic radiology

    International Nuclear Information System (INIS)

    Hernández-Ruiz, L.; Jimenez-Flores, Y.; Rivera-Montalvo, T.; Arias-Cisneros, L.; Méndez-Aguilar, R.E.; Uribe-Izquierdo, P.

    2012-01-01

    This paper presents the results of Environmental and Personnel Dosimetry made in a radiology area of a veterinary hospital. Dosimetry was realized using thermoluminescent (TL) materials. Environmental Dosimetry results show that areas closer to the X-ray equipment are safe. Personnel Dosimetry shows important measurements of daily workday in some persons near to the limit established by ICRP. TL results of radiation measurement suggest TLDs are good candidates as a dosimeter to radiation dosimetry in veterinary radiology. - Highlights: ► Personnel dosimetry in laboratory veterinary diagnostic was determined. ► Student workplaces are safe against radiation. ► Efficiency value of apron lead was determined. ► X-ray beams distribution into veterinarian laboratory was measured.

  17. An experimental system for thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Perry, K.E.G.; George, E.

    1965-08-01

    A thermoluminescent dosimeter (T.L.D.) reader has been developed for experimental investigations on the use of lithium fluoride for 'finger tip' dosimetry. The design of the reader is based on the maximum use of standard electronic units in the A.E.R.E. Type 2000 series but some new unit development has been necessary. The reader gives improved experimental facilities over present commercially-available designs. The technique for 'finger-tip' dosimetry is described and the initial experimental results are given. (author)

  18. Accuracy and precision in thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Marshall, T.O.

    1984-01-01

    The question of accuracy and precision in thermoluminescent dosimetry, particularly in relation to lithium fluoride phosphor, is discussed. The more important sources of error, including those due to the detectors, the reader, annealing and dosemeter design, are identified and methods of reducing their effects on accuracy and precision to a minimum are given. Finally, the accuracy and precision achievable for three quite different applications are discussed, namely, for personal dosimetry, environmental monitoring and for the measurement of photon dose distributions in phantoms. (U.K.)

  19. Thermoluminescent dosimetry in computed tomography

    International Nuclear Information System (INIS)

    Lara C, A.; Rivera M, T.; Osorio V, M.; Hernandez O, O.

    2016-10-01

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  20. Thermoluminescent dosimetry in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lara C, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Osorio V, M. [ISSSTE, Centro Medico Nacional 20 de Noviembre, Felix Cuevas 540, Col. del Valle, 03100 Ciudad de Mexico (Mexico); Hernandez O, O., E-mail: armando_lara_cam@yahoo.com.mx [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Ciudad de Mexico (Mexico)

    2016-10-15

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  1. Thermoluminescence dosimetry materials: properties and uses

    International Nuclear Information System (INIS)

    McKeever, S.W.S.; Moscovitch, M.; Townsend, P.D.

    1995-01-01

    This book selects a range of the most popular thermoluminescence dosemeter (TLD) materials in use today and provides a critical account of their thermoluminescence (TL) and dosimetric properties. The information provided includes in-depth discussions of TL mechanisms, including an account of luminescence properties, and relevant information regarding dosimetric characteristics. The book is intended for those involved in TLD materials research, and for technicians and workers involved in the practical application of these materials in TL dosimetry. The advent of modern spectroscopic methods for measuring TL emission spectra (the so-called ''3-D'' presentation) seemed to the authors to be an invitation to compile such spectra for all the major TLD materials. Further consideration led to an expansion of the initial idea to include a compilation of dosimetric properties. One intention is to provide a synopsis of the TL and dosimetric properties of the most widely used TLD materials currently available and to form a link between the solid state defect properties of these materials and their actual dosimetric properties. A second intention is to provide a solid framework from which future studies of TLD materials could be launched. Too often in the past research into TLD materials has been haphazard, to say the least. By illustrating the links between solid state physics and the radiation dosimetry properties of these materials the book points to the future and to the pressing need for enhanced research on TLD materials. (Author)

  2. Personnel radiation monitoring by thermoluminescence dosimetry (2000-2001)

    International Nuclear Information System (INIS)

    Mi-Cho-Cho, Daw; Hla-Hla-Win, Daw; Thin-Thin-Kraing

    2001-01-01

    Thermoluminescence dosimetry service was introduced in 1991. Personnel who exposed directly or indirectly to radiation is monitored by thermoluminescent dosimeter. TL materials used for thermoluminescent dosimeter are in the form of thin disc. Personnel whole-body and extremity doses are measured by thermoluminescence dosimetry. The Harshaw Model 4500 TLD reader and Vinten 654E TLD reader are used for TLD evaluation. At present about 600 radiation workers are provided with TLD for routine monitoring. It was found that most personnel had received within permissible dose recommended by the International Commission on Radiological Protection (ICRP). (author)

  3. Thermoluminescent dosimetry: theory, materials and applications

    International Nuclear Information System (INIS)

    Rosa, L.A.R.da.

    1978-01-01

    A survey about the thermoluminescence theory, the properties of the main thermoluminescent phosphors and their applications is presented. Some of the most important thermoluminescent readers are also mentioned [pt

  4. Historical note: thermoluminescent dosimetry (LiF) 1950-51

    International Nuclear Information System (INIS)

    Heckelsberg, L.F.

    1980-01-01

    The early history of thermoluminescent dosimetry has not been adequately described and one of the first workers in this field takes this opportunity to record more fully the history of the period. (author)

  5. Natural dose level determination at Johor State with thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Ahmad Termizi Ramli; Yusof Jasman

    1995-01-01

    This paperwork presented the results of using thermoluminescence dosimetry (TLD) method in measuring background dose level, which is done at State of Johor, South Malaysia. The problems faced also discussed

  6. Application of numerical analysis methods to thermoluminescence dosimetry

    International Nuclear Information System (INIS)

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

    1989-01-01

    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

  7. External dosimetry by Thermoluminescent Dosimetry Laboratory - IPEN/CNEN - Brazil

    International Nuclear Information System (INIS)

    Manzoli, Jose Eduardo; Carvalho, Ricardo Nunes

    2001-01-01

    The Thermoluminescence Dosimetry Laboratory, LDT - IPEN/CNEN - Brazil, executes around six thousand TLD readings monthly. It is responsible for the dose evaluation and registration and for all the manufacture process of preparation and sending the dosemeters which are used by IPEN itself, hospitals, industries, town halls, universities, etc. Although prepared to read many kinds of materials, actually the LDT reads only CaSO 4 :Dy detector chips. Chips, heating molds, plastic packaging and almost every material or instrument are made right here at IPEN. The readings are performed in a Bicron Harshaw TLD model 5500, but an old model 2000-AB is ready to be used if necessary. In this work it is presented some features of this important service realized to the IPEN workers and to the community. (author)

  8. Substance for thermoluminescent dosimetry of photon radiation in adipose tissue

    International Nuclear Information System (INIS)

    Kalmykov, L.Z.; Kandel', T.G.

    1983-01-01

    Substance composition for thermoluminescent photon dosimetry in adipose tissue is proposed which makes it possible to simplify dosimetric measurements and to improve their accuracy. The substance consists of powder-like thermoluminophor Li 2 B 4 O 7 (0.03%Mn) 48-52 mass % and bistriethylammonium dodecahydrododecaborane - 48-52 mass %. The above substance is equivalent in respect to dosimetry to adipose tissue within the 10 keV - 10 MeV energy range

  9. 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)

  10. Investigations on thermoluminescent dosimetry (TLD) with doped alumina ceramics

    International Nuclear Information System (INIS)

    Janas, R.; Huebner, K.

    1976-01-01

    Alumina ceramics doped and burned under various conditions have been investigated with regard to their suitability for thermoluminescent dosimetry. The production of ceramics is described. The properties essential for dosimetric purposes, such as glow curve, energy dose characteristics, fading, recoverability, lower detection limit and energy dependence, are indicated. The advantages and disadvantages of alumina ceramics are compared. (author)

  11. Dose measurements in dental radiology using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Chiara, Ana Claudia M. de; Costa, Alessandro M.; Pardini, Luiz Carlos

    2009-01-01

    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 2 , 101.5 +- 9.5 mGy.cm 2 and 116.8 +- 10.4 mGy.cm 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)

  12. Dosimetry techniques applied to thermoluminescent age estimation

    International Nuclear Information System (INIS)

    Erramli, H.

    1986-12-01

    The reliability and the ease of the field application of the measuring techniques of natural radioactivity dosimetry are studied. The natural radioactivity in minerals in composed of the internal dose deposited by alpha and beta radiations issued from the sample itself and the external dose deposited by gamma and cosmic radiations issued from the surroundings of the sample. Two technics for external dosimetry are examined in details. TL Dosimetry and field gamma dosimetry. Calibration and experimental conditions are presented. A new integrated dosimetric method for internal and external dose measure is proposed: the TL dosimeter is placed in the soil in exactly the same conditions as the sample ones, during a time long enough for the total dose evaluation [fr

  13. Thermoluminescence dosimetry in Northwest Puerto Rico

    International Nuclear Information System (INIS)

    Block, A.M.; Clements, R.G.; Rosa, L.I.; Santos, F.

    1975-01-01

    In October, 1973, the Puerto Rico Water Resources Authority sought the initiation of studies aimed at determining background radiological characteristics of the northwestern quadrant of Puerto Rico using thermoluminescent dosemeters. Some of the studies were required for supporting data for the environmental report submitted as part of the licensing procedure in the establishment of thermonuclear electric power generation facilities in Barrio Islote, Arecibo, Puerto Rico. Previous studies of radiological characteristics of the area had been made using sodium iodide sensing equipment in an airplane flying at an altitude of 500 ft. The results are expressed in counts per second, and provide useful comparative levels for radioactivity measured with the thermoluminescent detectors. (U.S.)

  14. Performance of thermoluminescent materials for high dose dosimetry

    International Nuclear Information System (INIS)

    Texeira, Maria I.; Cecatti, Sonia G.P.; Caldas, Linda V.E.

    2008-01-01

    Cases involving high-doses of ionizing radiation are becoming increasingly common.The objective of this work was to characterize thermoluminescent materials for the dosimetry of workers exposed to high doses. Samples of TLD-200, TLD-400 and TLD-800 pellets from Thermo Electron Corporation were studied in gamma high-doses. Dose-response curves were obtained for doses between 100 mGy and 100 Gy. The reproducibility, the lower detection limits and dose-response curves were obtained for all three materials. The different kinds of detectors show usefulness for dosimetry of workers exposed accidentally to high doses. (author)

  15. Food irradiation dosimetry using thermoluminescence of quartz sand

    International Nuclear Information System (INIS)

    Khan, H.M.; Ehlermann, D.A.E.

    1993-01-01

    Thermoluminescence of quartz sand, which is inert and concomitant to several food materials, has been investigated for applications in food irradiation dosimetry and detection of irradiated foods. The glow curves consist of at least three overlapping peaks from 100 to 420 C. The peak at lower temperature is not stable and decays quickly at room temperature. However, the peaks at higher temperature are stable and more useful for dosimetry work. The intensity of the peak at 360 C, measured using different optical filters, shows a linear response in the range of 0.05 to 23 kGy. Stability of these signals at different annealing temperatures has been investigated. Thermoluminescence from adhering minerals and contaminating dust in different food materials has been found useful for the detection of irradiation treatment. Since quartz is frequently one of these minerals, further computerized deconvolution of individual glow peaks from the complex glow curves of quartz sand was carried out which improves the dosimetric results. Possible applications of thermoluminescence of quartz sand in food irradiation dosimetry and detection of irradiated foods have been discussed. (orig.)

  16. Thermoluminescent dosimetry for LDEF experiment M0006

    International Nuclear Information System (INIS)

    Chang, J.Y.; Giangano, D.; Kantorcik, T.; Stauber, M.; Snead, L.

    1992-01-01

    Experiment M0006 on the Long Duration Exposure Facility had as its objective the investigation of space radiation effects on various electronic and optical components, as well as on seed germination. The Grumman Corporate Research Center provided the radiation dosimetric measurements for M0006, comprising the preparation of thermoluminescent dosimeters (TLD) and the subsequent measurement and analysis of flight exposed and control samples. In addition, various laboratory exposures of TLD's with gamma rays and protons were performed to obtain a better understanding of the flight exposures

  17. Thermoluminescence dosimetry of rare earth doped calcium ...

    Indian Academy of Sciences (India)

    Unknown

    CaAl2O4) doped with different rare earth ions have been studied and their suitability for radiation dosimetry applications is discussed. It is observed that monocalcium aluminate doped with cerium is a good dosimeter having linear response up to ...

  18. Thermoluminescent dosimetry in fluoroscopy of pediatric patients

    International Nuclear Information System (INIS)

    Garcia V, E.; Azorin N, J.; Hidalgo T, S.; Dies S, P.

    2016-10-01

    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)

  19. Ultraviolet dosimetry using thermoluminescent phosphors - an update

    International Nuclear Information System (INIS)

    Nagpal, J.S.

    1998-04-01

    Intrinsic response of various thermoluminescent (TL) materials such as CaSO 4 (Dy, Eu, Mn, Sm, Tb, or Tm), LiF (Mg, Cu, P), Mg 2 SiO 4 :Tb, CaF 2 :Dy, CaF 2 :Tb, ThO 2 :Tb and Al 2 O 3 (Si, Ti); cathodoluminescent phosphors Y 3 Al 5 O 12 :Ce, Y 3 Al 5 O 12 :Tb and Y(V,P)O 4 :Eu; and fluorescent lamp phosphors calcium halophosphate (Mn,Sb) and Ce Mg aluminate (Eu, Tb) to ultraviolet (UV) radiations has been studied. Intrinsic TL response of most of the phosphors is rate (radiant flux) dependent. For the first time, UV response of the materials is reported for a fixed total radiant energy (total UV dose), at a single radiant flux (260 μW.cm -2 ), for an appropriate comparison. A wide range of UV sensitivity is observed. Studies conducted using UV radiation from two unfiltered low pressure mercury lamps show significant differences in glow curves, as compared to those obtained with nearly monochromatic UV radiations. Photons of wavelength 365 nm induce bleaching of TL induced by 254 nm photons, in most of the materials. Sequential/tandem exposures to 254 nm and 365 nm photons have yielded new but alarming results in CaF 2 :Tb. Preferential induction and bleaching of specific TL glow peaks by 365 nm and 254 nm photons are interesting characteristics discovered in CaSO 4 :Eu. Photoluminescence studies of Tb 3+ and Eu 3+ activated phosphors have augmented the inferences drawn from the bleaching effects produced by 365 nm photons. Earlier work carried out on phototransferred thermoluminescence of CaSO 4 :Dy-teflon dosimeters, TLD-100, Mg 2 SiO 4 :Tb and Al 2 O 3 (Si,Ti) has also been reviewed. (author)

  20. An automated thermoluminescence dosimetry (TLD) system

    International Nuclear Information System (INIS)

    Kicken, P.J.H.; Huyskens, C.J.

    1979-01-01

    In the Health Physics Division of the Eindhoven University of Technology work is going on in developing an automated TLD-system. Process automization, statistical computation, dose calculation as well as dose recording are carried out, using a microcomputer and floppy disk unit. The main features of this TLD-system are its low costs, flexibility, easy to operate, and the feasibility for use in routine dosimetry as well as in complex TLD research. Because of its modular set-up several components of the system are multifunctional in other operations. The system seems suited for medium sized Health Physics groups. (Auth.)

  1. Statistical methods to evaluate thermoluminescence ionizing radiation dosimetry data

    International Nuclear Information System (INIS)

    Segre, Nadia; Matoso, Erika; Fagundes, Rosane Correa

    2011-01-01

    Ionizing radiation levels, evaluated through the exposure of CaF 2 :Dy thermoluminescence dosimeters (TLD- 200), have been monitored at Centro Experimental Aramar (CEA), located at Ipero in Sao Paulo state, Brazil, since 1991 resulting in a large amount of measurements until 2009 (more than 2,000). The data amount associated with measurements dispersion, since every process has deviation, reinforces the utilization of statistical tools to evaluate the results, procedure also imposed by the Brazilian Standard CNEN-NN-3.01/PR- 3.01-008 which regulates the radiometric environmental monitoring. Thermoluminescence ionizing radiation dosimetry data are statistically compared in order to evaluate potential CEA's activities environmental impact. The statistical tools discussed in this work are box plots, control charts and analysis of variance. (author)

  2. Personnel radiation monitoring by thermoluminescence dosimetry (1995-96)

    International Nuclear Information System (INIS)

    Daw Mi Cho Cho; Daw Yi Yi Khin; Daw San San; U Maung Maung Tin; Daw Hla Hla Win

    2001-01-01

    Personnel radiation monitoring which is the dose assessment of individual doses from external radiation received by radiation workers has been carried out by Thermoluminescence Dosimetry system consisting of a Vinten Toledo TLD reader, LiF dosimeters and associated equipment. The exposed TLD dosimeters were measured by TLD reader and the dose evaluation and dose registration were done on personal computer. Due to the records of 1995-96, most of the radiation workers complied with the permissible dose recommended by IAEA and ICRP 60. (author)

  3. Dosimetry Measurements around the Angiography Units Using Thermoluminescence Detectors (TLD)

    International Nuclear Information System (INIS)

    Salah El-den, T.; Shahein, A.Y.; Gomaa, M.A.

    2008-01-01

    The thermoluminescent dosimeters (TLDs) are widely used not only in the field of personnel monitoring (dosimetry) service for ionizing radiation to medical, and research communities, but also for measurements of X-rays emitted from different angiography's unit. Measurements ionizing radiation around the bed area during cardiac catheterization procedures using X-rays was measured. TLD Badges used to determine the annual effective doses, the safe distance for the staff to minimize radiation exposure and the effectiveness of shield and used leaded apron. The results indicated that annual effective dose for by angiography cardiac Catheterization room may exceed the limits

  4. New laser technique revives old ideas for thermoluminescence neutron dosimetry

    International Nuclear Information System (INIS)

    Braeunlich, P.; Brown, M.; Gasiot, J.; Fillard, J.P.

    1982-01-01

    Laser heating is discussed as a means to evaluate thermoluminescence dosimeters in neutron dosimetry. Direct energy coupling from the photon beam to the phonons of the TL material permits heating of thin layers with rates of temperature increase exceeding 10 4 Ks - 1 . Rapid TLD evaluation will allow the design of dosimetry badges containing a number of different small thin film TLD elements in various orientations and behind appropriate filters, hydrogenous radiators, etc. Desired redundance is readily possible by using back-up TLDs for every specific task. Reading occurs with a scanning laser beam rather than by mechanically manipulating the TLD toward a fixed heat source. Improvements in the signal-to-noise ratio of up to a factor of 1000 are readily obtained. Thus, sensitive thin-film TLDs can be designed with negligible self-shielding for thermal neutrons in albedo applications and with known, nearly energy dependent cavity correction factors for dosimetry in mixed n-#betta# fields. Due to the greatly increased sensitivity possible with fast laser heating, significant advances are expected in the fast neutron dosimetry techniques which are based on hydrogeneous proton radiators or LET-dependent slow peak formation

  5. The IAEA/WHO thermoluminescent dosimetry intercomparison used for the improvement of clinical dosimetry

    International Nuclear Information System (INIS)

    Racoveanu, N.T.

    1981-01-01

    Results of thermoluminescent dosimetry collected over 5 years in the Eastern Mediterranean region of WHO were analyzed in an attempt to improve clinical dosimetry. Data for 16 radiotherapy departments showed considerable inconsistencies. It was found that the clinical dosemeters used by 3 of the departments were not working properly. The remainder of the departments had one or more dosemeters in perfect working order but the procedure for measuring machine output was inadequate or the correction factors (pressure, temperature) were wrongly applied due to lack of reliable instruments for such measurements. Problems encountered in the sending and returning of TLD dosemeters for assessment are discussed

  6. Neodymium oxide: A new thermoluminescent material for gamma dosimetry

    Science.gov (United States)

    Soliman, C.

    2006-10-01

    In the present study thermoluminescence (TL) glow curves of commercial and gamma (0.001 Gy to 100 kGy) exposed neodymium oxide (Nd 2O 3) have been investigated. The commercial glow curve is simple with TL peaks at 310, 350 and 385 °C. The TL sensitivity was enhanced to ˜4.7 times the original value when the investigated material was subject to pre-heating treatment at 800 °C for 1 h. The effect of storage time at room temperature has been monitored for different γ-doses. The combination of good γ-dose response and high stability of defects offer the possibility of applying the investigated material to γ-ray dosimetry in radiotherapy and experimental radiology range.

  7. Intrinsic thermoluminescence of NaCl:Tl in UV dosimetry

    International Nuclear Information System (INIS)

    Barghare, S.P.; Joshi, R.V.; Joshi, T.R.; Kathuria, S.P.

    1982-01-01

    NaCl:Tl(T) phosphor is found to have high intrinsic thermoluminescence (TL) sensitivity to 253.7 nm UV-radiation. The dosimetric glow peak II grows sublinearly with increase in UV dose in the range 10 3 to 10 6 JM -2 . The other requirements of an efficient dosimeter material such as high storage stability, matching of the spectral response of detector tube and TL-emission from phosphor, reproducibility, desirable size and shape, easy availability in powder, pellet and crystal forms at cheaper rates, and repeated re-usability of the same phosphor without much difficulty, etc., are additional factors which strengthen the claim of NaCl:Tl(T) phosphor as UV dosimetric material. It is proposed that present NaCl:Tl(T) material is suitable TL-phosphor for UV dosimetry in the range 10 3 to 10 6 JM -2 . (author)

  8. Thermoluminescent properties of CVD diamond: applications to ionising radiation dosimetry

    International Nuclear Information System (INIS)

    Petitfils, A.

    2007-09-01

    Remarkable properties of synthetic diamond (human soft tissue equivalence, chemical stability, non-toxicity) make this material suitable for medical application as thermoluminescent dosimeter (TLD). This work highlights the interest of this material as radiotherapy TLD. In the first stage of this work, we looked after thermoluminescent (TL) and dosimetric properties of polycrystalline diamond made by Chemically Vapor Deposited (CVD) synthesis. Dosimetric characteristics are satisfactory as TLD for medical application. Luminescence thermal quenching on diamond has been investigated. This phenomenon leads to a decrease of dosimetric TL peak sensitivity when the heating rate increases. The second part of this work analyses the use of synthetic diamond as TLD in radiotherapy. Dose profiles, depth dose distributions and the cartography of an electron beam obtained with our samples are in very good agreement with results from an ionisation chamber. It is clearly shown that CVD) diamond is of interest to check beams of treatment accelerators. The use of these samples in a control of treatment with Intensity Modulated Radiation Therapy underlines good response of synthetic diamond in high dose gradient areas. These results indicate that CVD diamond is a promising material for radiotherapy dosimetry. (author)

  9. Study of some thermoluminescent phosphors for the dosimetry of ionizing radiations

    International Nuclear Information System (INIS)

    Jaafari, M.

    1983-01-01

    Thermoluminescence dosimetry techniques are reviewed and interactions radiation matter are recalled. The need for new phosphors is evidenced. Numerous phosphors are examined and calcium, strontium and barium sulfides are synthetized and deposited on glass supports. The thermoluminescence of the dosimeters obtained with these materials is analyzed [fr

  10. Thermoluminescence dosimetry of gamma rays from the fallout of the Semipalatinsk nuclear tests

    International Nuclear Information System (INIS)

    Takada, J.; Hoshi, M.; Endo, S.; Yamamoto, M.; Nagatomo, T.; Gusev, B.I.; Rozenson, R.I.; Apsalikov, K.N.; Tchaijunusova, N.J.

    1996-01-01

    Field missions were sent to several settlements near the Semipalatinsk nuclear test site out in order to investigate dosimetry for the residents in 1995. The results of measurements of environmental radiation doses and thermoluminescence dosimetry in some villages near the Semipalatinsk nuclear test site are presented. The radiation levels in several villages are the natural background level in 1995, 6 years after the final nuclear explosion. On the other hand, thermoluminescence dosimetry revealed significant radiation exposure to residents in this area due to nuclear tests. (author)

  11. Thermoluminescence dosimetry of electronic components from personal objects

    International Nuclear Information System (INIS)

    Beerten, Koen; Woda, Clemens; Vanhavere, Filip

    2009-01-01

    Owing to the existence of ceramic materials inside common personal objects such as cellular phones and USB flash drives, these objects may be very useful in emergency (accident) dosimetry. Here we will present initial results regarding the dosimetric properties as determined by thermoluminescence (TL) from two alumina-rich electronic components from a USB flash drive. The TL method was applied in order to investigate the potential of conventional TL equipment for such purposes. For comparison, the optically stimulated luminescence (OSL) of the components was investigated as well. The studied components are ceramic resonators and alumina-based substrates from electrical resistors. The results show that various TL-related properties such as fading, optical stability and zero-dose response are different for the two investigated components. On the basis of these properties, the ceramic resonator was selected for dose recovery tests using TL and OSL. The given dose could reliably be determined using both methods, assuming that prompt measurement and/or fading correction is possible.

  12. Practical use of lithium borate in thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Chavaudra, J.; Nguyen, J.; Marinello, G.; Brule, A.M.

    1976-01-01

    The functional principles of thermoluminescent dosimeters are recalled: heating, apparatus for measuring the emitted light, circulation of nitrogen, reference source. The essential role played by the circulation of nitrogen over the dosimeters which equilibrates the temperature of the photomultiplier, reduces the emission of unwanted light, prevents the combustion of dust or other possible impurities and finally improves the accuracy of the measurements even for high doses, is underlined. Lithium borate is taken as an example and a simple method for finding the optimum working conditions for the heating apparatus of the planchette in the most simple T.L.D. readers and in those where the heating apparatus of the planchette has a pre-heating phase is proposed. The dosimetric properties of lithium borate incorporated in thin teflon discs (type DLB. 0.13 and 0.4) are studied. This shows itself to be very interesting for certain uses because it is a solid dosimeter which does not require annealing between two measurements. The accuracy of the measurements obtained with this material, the stability of the response relative to the delay between radiation and reading (fading), the response relative to the absorbed dose plus the nature and the energy of the rays, are presented with the usual reservations made for this type of dosimetry [fr

  13. Thermoluminescence dosimetry in quality imaging in CR mammography systems

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E.; Franco E, J.G. [UAM-Xochimilco, 04960 Mexico D.F. (Mexico); Azorin N, J. [UAM-Iztapalapa, 09340 Mexico D.F. (Mexico); Diaz G, J.A.I. [CICATA, Unidad Legaria, Av. Legaria 694, 11599 mexico D.F. (Mexico); Arreola, M. [Department of Radiology, Shands Hospital at UF, PO Box 100374, Gainesville, FL 32610-0374 (United States)

    2006-07-01

    The aim of this work is to estimate the average glandular dose with Thermoluminescence Dosimetry (TLD) and comparison with quality imaging in CR mammography. For measuring dose, FDA and ACR use a phantom, so that dose and image quality are assessed with the same test object. The mammography is a radiological image to visualize early biological manifestations of breast cancer. Digital systems have two types of image-capturing devices, Full Field Digital Mammography (FFDM) and CR mammography. In Mexico, there are several CR mammography systems in clinical use, but only one CR mammography system has been approved for use by the FDA. Mammography CR uses a photostimulable phosphor detector (PSP) system. Most CR plates are made of 85% BaFBr and 15% BaFI doped with europium (Eu) commonly called barium fluoro halide. We carry out an exploratory survey of six CR mammography units from three different manufacturers and six dedicated x-ray mammography units with fully automatic exposure. The results show three CR mammography units (50%) have a dose that overcomes 3.0 mGy and it doesn't improve the image quality and dose to the breast will be excessive. The differences between doses averages from TLD system and dosimeter with ionization chamber are less than 10%. TLD system is a good option for average glandular dose measurement. (Author)

  14. Thermoluminescence dosimetry in quality imaging in CR mammography systems

    International Nuclear Information System (INIS)

    Gaona, E.; Franco E, J.G.; Azorin N, J.; Diaz G, J.A.I.; Arreola, M.

    2006-01-01

    The aim of this work is to estimate the average glandular dose with Thermoluminescence Dosimetry (TLD) and comparison with quality imaging in CR mammography. For measuring dose, FDA and ACR use a phantom, so that dose and image quality are assessed with the same test object. The mammography is a radiological image to visualize early biological manifestations of breast cancer. Digital systems have two types of image-capturing devices, Full Field Digital Mammography (FFDM) and CR mammography. In Mexico, there are several CR mammography systems in clinical use, but only one CR mammography system has been approved for use by the FDA. Mammography CR uses a photostimulable phosphor detector (PSP) system. Most CR plates are made of 85% BaFBr and 15% BaFI doped with europium (Eu) commonly called barium fluoro halide. We carry out an exploratory survey of six CR mammography units from three different manufacturers and six dedicated x-ray mammography units with fully automatic exposure. The results show three CR mammography units (50%) have a dose that overcomes 3.0 mGy and it doesn't improve the image quality and dose to the breast will be excessive. The differences between doses averages from TLD system and dosimeter with ionization chamber are less than 10%. TLD system is a good option for average glandular dose measurement. (Author)

  15. Thermoluminescent dosimetry of new phosphors of Zn O exposed to beta radiation

    International Nuclear Information System (INIS)

    Cruz V, C.; Burruel I, S.E.; Grijalva M, H.; Barboza F, M.; Bernal, R.

    2004-01-01

    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)

  16. Evaluation of glasses containing cadmium for high dose dosimetry by the thermoluminescence technique

    International Nuclear Information System (INIS)

    Carvalho, Gabriel Soares Marchiori de; Ferreira, Pamela Zati; Cunha, Diego Merigue da; Dantas, Noelio Oliveira; Silva, Anielle C.A.; Perini, Ana Paula; Neves, Lucio Pereira; Carrera, Betzabel Noemi Silva; Watanabe, Shigueo

    2016-01-01

    New glass matrices were evaluated for high dose dosimetry by the thermoluminescence technique. Their nominal composition are 20Li_2CO_3.10Al_2O_3.15CdO.55B_2O_3 and 20Li_2CO_3.10Al_2O_3.20CdO.50B_2O_3 (mol%). The glass matrices were irradiated with different doses: 50, 100, 200, 500, 700 and 900 Gy, and the thermoluminescence emission curves were obtained for each of these values. The results show a great potential of using these matrices in high dose dosimetry. (author)

  17. The application of an automated thermoluminescence dosimetry system to environmental γ-dosimetry

    International Nuclear Information System (INIS)

    Jones, A.R.

    1977-07-01

    A personnel monitoring system comprising thermoluminescent dosimeters (TLDs) and an automatic TLD reader has been applied to environmental gamma dosimetry. For this purpose the accuracy of measurement at low exposures (10 to 100 mR) acquired over long periods (3 or 12 months) is important. To improve the accuracy and reliability of the system for this application the following steps were taken: the dosimeters were sensitized by irradiation with γ-rays and annealed while being irradiated with UV light; the sensitivity of each, identified dosimeter was measured and used to correct exposure measurements; the gasketted holders were modified to contain TLDs mounted on two identified plaques. Measurements of linearity, variability (with and without individual calibration) fading and energy dependence are presented. (author)

  18. Studies on 192Ir afterloading irradiation of the canine prostate with special consideration of thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Reuter, M.

    1986-01-01

    A method for high dose rate afterloading irradiation of the prostate with iridium 192 was developed. The isodoses of the urethra and rectum, which were measured by means of thermoluminescent dosimetry, showed deviations from the doses pre-calculated by computer (BRACHY), because this calculation is based on an anatomically ideal condition. (MBC) [de

  19. Year 2000 compliance concerns with the ISA Thermoluminescent Dosimetry Data Processing (TL-DP) software system

    Energy Technology Data Exchange (ETDEWEB)

    Saviz, K.

    1998-05-26

    The year 2000 is rapidly approaching, and there is a good chance that computer systems that utilize two digit year dates will experience problems in retrieval of date information. The ISA Thermoluminescent Dosimetry Data Processing (TL-DP) software and computer system has been reviewed for Year 2000 compliance issues.

  20. Year 2000 compliance concerns with the ISA Thermoluminescent Dosimetry Data Processing (TL-DP) software system

    International Nuclear Information System (INIS)

    Saviz, K.

    1998-01-01

    The year 2000 is rapidly approaching, and there is a good chance that computer systems that utilize two digit year dates will experience problems in retrieval of date information. The ISA Thermoluminescent Dosimetry Data Processing (TL-DP) software and computer system has been reviewed for Year 2000 compliance issues

  1. Obtention of a thermoluminescent material for dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.

    1990-01-01

    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 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)

  2. Personnel radiation dosimetry laboratory accreditation programme for thermoluminescent dosimeters : a proposal

    International Nuclear Information System (INIS)

    Bhatt, B.C.; Srivastava, J.K.; Iyer, P.S.; Venkatraman, G.

    1993-01-01

    Accreditation for thermoluminescent dosimeters is the process of evaluating a programme intending to use TL personnel dosimeters to measure, report and record dose equivalents received by radiation workers. In order to test the technical competence for conducting personnel dosimetry service as well as to decentralize personnel monitoring service, it has been proposed by Radiological Physics Division (RPhD) to accredit some of the laboratories, in the country. The objectives of this accreditation programme are: (i) to give recognition to competent dosimetry processors, and (ii) to provide periodic evaluation of dosimetry processors, including review of internal quality assurance programme to improve the quality of personnel dosimetry processing. The scientific support for the accreditation programme will be provided by the scientific staff from Radiological Physics Division (RPhD) and Radiation Protection Services Division (RPSD). This paper describes operational and technical requirements for the Personnel Radiation Dosimetry Laboratory Accreditation Programme for Thermoluminescent Dosimeters for Personnel Dosimetry Processors. Besides, many technical documents dealing with the TL Personnel Dosimeter System have been prepared. (author). 5 refs., 2 figs

  3. Neutron dosimetry using activation of thermoluminescent CaSO 4

    Science.gov (United States)

    Azorín, Juan; Gutiérrez, Alicia

    1984-11-01

    Sulfur activation in calcium sulfate doped with dysprosium (CaSO 4:Dy) thermoluminescent powder, which is bound in pure sulfur, has been used to measure the fast neutron dose at the tangential beam port of a Triga Mark III reactor. After a post-irradiation time of 3 d, the dosimeters were annealed at 600°C for 30 min in order to erase all the thermoluminescence acquired during the irradiation. The dosimeters were then stored to allow self-irradiation by betas from 32P produced by sulfur activation. The thermoluminescent signal accumulated during a post-irradiation time of 20 d due to a neutron fluence of 2.2 × 10 11 n/cm 2 was equivalent to an absorbed dose of 10 mGy of 60Co gamma rays. The thermoluminescence as a function of fast neutron dose fitted to a straight line on a log-log scale from 1 Gy to 10 4Gy.

  4. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram

    International Nuclear Information System (INIS)

    Cruz C, D.; Azorin N, J.; Saucedo A, V.M.; Barajas O, J.L.

    2005-01-01

    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)

  5. Dosimetry of accidents using thermoluminescence of dental restorative porcelains

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.; Rosa, L.A.R. da; Cunha, P.G. da

    1986-01-01

    The thermoluminescence (TL) properties of dental restorative porcelain were investigated with the aim of using this material as a TL dosemeter to estimate high doses in radiological accidents. The irradiations were carried out with a 60 Co gamma source and X rays with effective energies from 29 to 95 KeV. The samples have a limit of detection at about 50R and their reproducibility is better than 15%. Linearity was observed from 50 to 5000R. (Author) [pt

  6. Evaluation of glasses containing cadmium for high dose dosimetry by the thermoluminescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Gabriel Soares Marchiori de; Ferreira, Pamela Zati; Cunha, Diego Merigue da; Dantas, Noelio Oliveira; Silva, Anielle C.A.; Perini, Ana Paula; Neves, Lucio Pereira, E-mail: lucio.neves@ufu.br [Universidade Federal de Uberlandia (INFIS/UFU), MG (Brazil). Instituto de Fisica; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil); Carrera, Betzabel Noemi Silva; Watanabe, Shigueo [Universidade de Sao Paulo (IF/USP), SP (Brazil). Instituto de Fisica

    2016-07-01

    New glass matrices were evaluated for high dose dosimetry by the thermoluminescence technique. Their nominal composition are 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.15CdO.55B{sub 2}O{sub 3} and 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.20CdO.50B{sub 2}O{sub 3} (mol%). The glass matrices were irradiated with different doses: 50, 100, 200, 500, 700 and 900 Gy, and the thermoluminescence emission curves were obtained for each of these values. The results show a great potential of using these matrices in high dose dosimetry. (author)

  7. Study of a new glass matrix by thermoluminescent technique for high-dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pamela Z.; Carvalho, Gabriel S. Marchiori de; Cunha, Diego M. da; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P., E-mail: anapaula.perini@ufu.br [Universidade Federal de Uberlandia (UFU), MG (Brazil). Instituto de Fisica; Linda, V.E. Caldas [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Carrera, Betzabel N.S.; Watanabe, Shigueo [Universidade de Sao Paulo (IF/USP), Sao Paulo, SP (Brazil). Instituto de Fisica

    2016-07-01

    The thermoluminescence technique is widely used for both personal and for high-dose dosimetry. In this work, the thermoluminescence technique was utilized to study a new glass matrix, with nominal composition of 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.30BaO.40B{sub 2}O{sub 3} (mol%), irradiated with different doses in a {sup 60}Co source. The glow curves and the dose-response curve were obtained for radiation doses of 10, 50, 100, 200 e 700 Gy. The results showed that this new glass matrix has potential use in high-dose dosimetry. (author)

  8. In vivo dosimetry using thermoluminescent detector in cancer therapy of head and neck

    International Nuclear Information System (INIS)

    Viegas, Claudio C.B.; Batista, D.V.; Campos, A.M.; Lopes, R.T.

    2002-01-01

    The viability and implementation of a routine in vivo dosimetry, using thermoluminescent dosemeters (TLD), at the radiotherapy section of the National Institute of Cancer in Brazil, in the case of head and neck treatment is shown. In order to reach that aim, the characteristics of the response of the LiF:Mg;Ti (TLD-100) thermoluminescent detectors in powder form were determined. The performed of this detector for in vivo dosimetry was testes using an RANDO Alderson anthropomorphic phantom and, once their adequability proved for the kind of measurements proposed , it was used for dose assessment in the case of tumour treatments in the head and neck regions, for Cobalt-60 irradiations. (author)

  9. Proposal of a methodology for quality control in thermoluminescent dosimetry laboratory

    International Nuclear Information System (INIS)

    Feital, Joao Carlos da S.; Almeida, Claudio Domingues de; Bezerra, Marcos A.

    2005-01-01

    Taken into account that in thermoluminescence dosimetry adequate selection procedures as well as accurate TLD readings are necessary, this paper presents results of methodology that can be applied as part of quality control programs in thermoluminescence dosimetry laboratories. For the experiment, a set of 200 TLDs ( LiF 100 ) were used and 9 from which were selected, a standard source of Cs -137 , a PTW kiln, a TL 'Harshaw' reader - model 5500 operating under the 'Win Rem' software and a Sr 90 / Y 90 'Bicron' irradiator. In the proceeding the selected dosimeters were irradiated and read 28 times during 18 months, then by one of the standard deviation properties, values up to 14 % were found, for a confidence level of 95 %. The results found and the bibliographic data related to the responses (arbitrary reading) in the crystals used in TLDs, have shown that this methodology can be applied in quality control programs. (author)

  10. Thermoluminescent dosemeters characterization for patient dosimetry in diagnostic radiology preliminary results

    International Nuclear Information System (INIS)

    Castro, William J.; Squair, Peterson L.; Gonzaga, Natalia B.; Nogueira, Maria S.; Silva, Teogenes A. da

    2009-01-01

    The determination of the metrological characteristics of thermoluminescent (TL) dosimeters plays an important role in dosimetry of patients submitted to x-ray examinations for diagnostic purpose. Entrance surface doses can be measured with TL dosimeters to verify the compliance with the diagnostic reference levels. Organ doses can be estimated through TL measurements in an anthropomorphic phantom which it allows the radiation risk assessment. In this work, LiF:Mg,Ti (TLD-100) rod and chip thermoluminescent dosimeters were characterized considering their use for patient dosimetry in computerized tomography and mammography. Preliminary results showed that TL dosimeters have a response reproducibility of 7.8% and 4.8% and homogeneity of 18.4% and 6.5% for rod and chip shapes, respectively. (author)

  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. Use of thermoluminescent dosimetry in gamma radiation fields studies

    International Nuclear Information System (INIS)

    Carron, W.

    1987-01-01

    The depth-dose curves for gamma rays in material of interest to agronomy were obtained using lithium fluoride thermoluminescent dosimeters. The dose conversion factors for LiF were determined from curves of the absorved dose versus depth in water, wood and soil. Mathematics equations were chosen to best fit these curves. In the view of the results we came to the conclusion that in the studied materials the absorved radiation dose presents a great variation to the depth and could be correlated through of the exponential regression. (author)

  13. Study of thermoluminescence and semiconductors in dosimetry. Application of dosimetry of the whole body in view of bone marrow grafting

    International Nuclear Information System (INIS)

    Naudy, Suzanne.

    1981-05-01

    From this study one deduces that thermoluminescence remains the moss reliable process for the measurement of dose in vivo: precision, reproducibility and easy calibration. The semiconductors do not present the quality needed to a reliable use in dosimetry. The limits of each techniques have been established in our study, we have applied them simultaneously in dosimetric irradiations of the whole body in view of bone marrow grafting. Semiconductors allow to follow the irradiation and to intervene instantaneously if necessary, thermoluminescent dosimeter insure precise knowledge of the delivered dose. One hundred and ten patients have been treated before bone narrow grafting at the Gustave Roussy Institut and fifty two of them render account of the results obtained with this experimental dosimetric protocol [fr

  14. In vivo dosimetry with semiconductor and thermoluminescent detectors applied to head and neck cancer treatment

    International Nuclear Information System (INIS)

    Viegas, Claudio Castelo Branco

    2003-03-01

    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)

  15. Thermoluminescence dosimetry: State-of-the-art and frontiers of future research

    International Nuclear Information System (INIS)

    Horowitz, Y.S.

    2014-01-01

    The state-of-the-art in the use of thermoluminescence for the measurement of energy imparted by ionizing radiation is discussed. Emphasis is on the advantages obtainable by the use of computerized glow curve analysis in (i) quality control, (ii) low dose environmental dosimetry, (iii) medical applications (especially precision) and microdosimetric applications, and (iv) mixed field ionization-density–dosimetry. Possible frontiers of future research are highlighted: (i) vector representation in glow curve analysis, (ii) combined OSL/TL measurements, (iii) detection of sub-ionization electrons, (iv) requirements for new TL materials and (v) theoretical subjects involving kinetic modeling invoking localized/delocalized recombination applied to dose response and track structure theory including creation of defects. - Highlights:: • State of the art in thermoluminescence dosimetry. • Benefits of computerized glow curve deconvolution. • Frontiers of future research:new materials, mixed-field dosimetry. • Localized/delocalized kinetic theory:ionization density dependence. • Kinetic theory:creation of defects:track structure theory

  16. Thermoluminescent phosphors for ultraviolet radiation dosimetry - a review

    International Nuclear Information System (INIS)

    Nagpal, J.S.

    2001-01-01

    Intrinsic TL response of CaSO 4 , CaF 2 , Al 2 O 3 (Si,Ti), Mg 2 SiO 4 : Tb and lamp phosphors to ultraviolet radiation is reviewed. Taking into consideration the characteristics such as afterglow at RT, rate/flux dependence, linearity of response, useful range, spectral dependence and effect of sequential/tandem UV exposures CaF 2 :Eu 2+ is an ideal TL dosemeter for UV radiation dosimetry. (author)

  17. A preliminary study on thermoluminescence of AMOLED glass from mobile phones for retrospective dosimetry

    International Nuclear Information System (INIS)

    Kim, Hyoungtaek; Lee, Jungil; Chang, Insu; Lee, Seung Kyu; Kim, Min Chae; Park, Sang Won; Kim, Jang-Lyul; Kim, Bong-Hwan; Yu, Hyungjoon; Kim, Ah-reum

    2017-01-01

    Since mobile phones are always carried by individuals, the retrospective dosimetry using thermoluminescence (TL) and optically stimulated luminescence (OSL) characteristics of elements in mobile phone is intensively developing nowadays due to its advantages over conventional biological dosimetry techniques. Using a TL and OSL method on resistors and inductors in a mobile phone, a low background dose (zero dose) about tens of mGy is acquired in previous study. Radiation workers have to wear a dosimeter to assess individual exposure during their works. This monitoring system facilitate a fast medical treatment for highly exposed workers in case of a radiation accident. In the event of large-scale radiation accidents, where most of the subjects are ordinary people, it is difficult to evaluate the individual dose due to the absence of dosimeters. A technique for dose evaluation using a radiation dependency of various materials in the absence of a dosimeter is called retrospective dosimetry.

  18. Thermoluminescent dosimetry in computed tomography for pediatric patients

    International Nuclear Information System (INIS)

    Medrano S, A. C.; Medina A, O.; Hidalgo T, S.; Azorin N, J.

    2015-10-01

    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)

  19. Hydrothermally synthesized barium fluoride nanocubes for thermoluminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bhadane, Mahesh S.; Dahiwale, S. S.; Bhoraskar, V. N.; Dhole, S. D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, Savitribai Phule Pune University, Pune-411007 (India)

    2016-05-23

    In this work, we report a hydrothermally synthesized Dy doped BaF{sub 2} (BaF{sub 2}:Dy) nanocubes and its Thermoluminescence studies. The synthesized BaF{sub 2}:Dy samples was found to posses FCC structure and having average size ~ 60-70 nm, as revealed through X-Ray Diffraction. Cubical morphology having size ~90 nm was observed from TEM analysis. The {sup 60}Co γ- ray irradiated BaF{sub 2}:Dy TL dosimetric experiments shows a pre-dominant single glow peak at 153 °C, indicating a single level trap present as a metastable state. Furthermore, BaF{sub 2}:Dy nanophosphor shows a sharp linear response from 10 Gy to 3 kGy, thus it can be applicable as a gamma dosimeter.

  20. Synthesis of CaF2: dy for thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Yamato, M.E.P.; Vasconcelos, D.A.A. de; Asfora, V.K.; Khoury, H.J.; Santos, R.A.; Barros, V.S.M.

    2015-01-01

    Calcium Fluoride doped with dysprosium is a known thermoluminescent material for applications that require highly sensitive dosimeters. Research in novel methods such as Combustion Synthesis (CS) has been ongoing for several years at the University of Pernambuco. The method uses the heat of the oxi-redox reaction a between nitrate and a fuel. This work presents results of CaF 2 :Dy produced by combustion synthesis under different fabrication conditions. Samples were prepared by mixing stoichiometric amounts of calcium nitrate, urea and ammonium nitrate in a beaker under vigorous stirring. The resulting gel was transferred to a pre-heated muffle furnace were the combustion reaction occurred after a few minutes. For comparison, a variation of the production method with the same amounts of nitrate, ammonium fluoride and dopant, but without using the fuel was prepared. For both methods the resulting powder was pelleted and irradiated with Co-60 gamma radiation. The reproducibility and sensitivity for gamma dose irradiation was tested and results showed that optimum TL sample reproducibility was without the urea as fuel. Samples were then prepared with 0.05, 0.10, 0.15 and 0.20 mol% Dy concentration. The highest TL sensitivity was found for samples with 0.15 mol% Dy and sintered at 400 deg C for 3.5 h in air. The TL emission spectra, obtained using a Hammamatsu optical spectrometer, was comparable with commercial CaF 2 :Dy. Thermoluminescence was measured in a Harshaw-Bicron 3500 TL Reader. The glow curve showed stable dosimetric peaks at around 200, 235 and 300 deg C were a linear dose response curve was obtained for the range 100 mGy to 1000 mGy. (author)

  1. Synthesis and thermoluminescence of LaAlO3:Pr3+ to UVC radiation dosimetry

    International Nuclear Information System (INIS)

    Morales-Hernández, A.; Zarate-Medina, J.; Contreras-García, M.E.; Azorín-Nieto, J.; Rivera-Montalvo, T.

    2016-01-01

    Thermoluminescent (TL) response of trivalent praseodymium ion doped lanthanum aluminate (LaAlO 3 :Pr 3+ ) obtained by Pechini method and Spray Dryer was studied. TL response of LaAlO 3 :Pr 3+ powders submitted at 1600 °C exhibited one peak centered at 157 °C. Sensitivity of LaAlO 3 :Pr 3+ was improved in around 90 times compared with undoped LaAlO 3 . TL response as a function of wavelength showed a maximum in 230 nm. Dosimetric characteristics of LaAlO 3 :Pr 3+ under UVR radiation effects were analyzed. Evaluation of activation energy was obtained by Glow Fit v.1.3 software. Experimental results about thermoluminescent characteristics of LaAlO 3 :Pr 3+ suggest as good candidate to be employed as a complementary thermoluminescent device with other TL phosphors as aluminum oxide - Highlights: • High sensitivity of new phosphor to UVC dosimetry was is studied. • Thermoluminescence response of LaAlO 3 :Pr 3+ is presented. • LaAlO 3 :Pr 3+ is suggested as UVCR dosimeter. • TL response of LaAlO 3 :Pr 3+ has dependence on sintering temperature.

  2. Thermoluminescence properties of irradiated commercial color pencils for accidental retrospective dosimetry

    International Nuclear Information System (INIS)

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

    2015-01-01

    Color pencils are widely used mostly in kindergartens, in schools and could be found in all houses with families having young children. Their wide spread use in modern times as well as their chemical composition, consisting mostly of Si and Al, constitute two strong motivations towards exploiting their use as accidental retrospective thermoluminescent dosimeters. The present manuscript reports on the study of colored pencils manufactured by a commercial brand in China which is very common throughout Turkey. The preliminary results discussed in the present work illustrated encouraging characteristics, such as the presence of a trapping level giving rise to natural TL in a temperature range that is sufficiently high. Specific thermoluminescence features of this peak, such as glow peak shape and analysis, anomalous fading, thermal quenching, reproducibility, linearity and recovery ability to low attributed doses were studied. The results suggest that the color pencils could be effectively used in the framework of retrospective thermoluminescent dosimetry with extreme caution, based on multiple aliquot protocols. - Highlights: • Thermoluminescence of the inner part of commercial colored pencils was studied. • The presence of a trapping level giving rise to natural TL at 260 °C was yielded. • Deco analysis, anomalous fading, thermal quenching, reproducibility, linearity and recovery ability of this peak were studied

  3. Percentage depth dose evaluation in heterogeneous media using thermoluminescent dosimetry

    Science.gov (United States)

    da Rosa, L.A.R.; Campos, L.T.; Alves, V.G.L.; Batista, D.V.S.; Facure, A.

    2010-01-01

    The purpose of this study is to investigate the influence of lung heterogeneity inside a soft tissue phantom on percentage depth dose (PDD). PDD curves were obtained experimentally using LiF:Mg,Ti (TLD‐100) thermoluminescent detectors and applying Eclipse treatment planning system algorithms Batho, modified Batho (M‐Batho or BMod), equivalent TAR (E‐TAR or EQTAR), and anisotropic analytical algorithm (AAA) for a 15 MV photon beam and field sizes of 1×1,2×2,5×5, and 10×10cm2. Monte Carlo simulations were performed using the DOSRZnrc user code of EGSnrc. The experimental results agree with Monte Carlo simulations for all irradiation field sizes. Comparisons with Monte Carlo calculations show that the AAA algorithm provides the best simulations of PDD curves for all field sizes investigated. However, even this algorithm cannot accurately predict PDD values in the lung for field sizes of 1×1 and 2×2cm2. An overdosage in the lung of about 40% and 20% is calculated by the AAA algorithm close to the interface soft tissue/lung for 1×1 and 2×2cm2 field sizes, respectively. It was demonstrated that differences of 100% between Monte Carlo results and the algorithms Batho, modified Batho, and equivalent TAR responses may exist inside the lung region for the 1×1cm2 field. PACS number: 87.55.kd

  4. Thermoluminescence in CVD diamond films: application to actinometric dosimetry

    International Nuclear Information System (INIS)

    Barboza-Flores, M.; Melendrez, R.; Chernov, V.; Castaneda, B.; Pedroza-Montero, M.; Gan, B.; Ahn, J.; Zhang, Q.; Yoon, S.F.

    2002-01-01

    Diamond is considered a tissue-equivalent material since its atomic number (Z=6) is close to the effective atomic number of biological tissue (Z=7.42). Such a situation makes it suitable for radiation detection purposes in medical applications. In the present work the analysis is reported of the thermoluminescence (TL) and dosimetric features of chemically vapour deposited (CVD) diamond film samples subjected to ultraviolet (UV) irradiation in the actinometric region. The TL glow curve shows peaks at 120, 220, 320 and 370 deg. C. The 120 and 370 deg. C peaks are too weak and the first one fades away in a few seconds after exposure. The overall room temperature fading shows a 50% TL decay 30 min after exposure. The 320 deg. C glow peak is considered to be the most adequate for dosimetric applications due to its low fading and linear TL behaviour as a function of UV dose in the 180-260 nm range. The TL excitation spectrum presents a broad band with at least two overlapped components around 205 and 220 nm. The results indicate that the TL behaviour of CVD diamond film can be a good alternative to the currently available dosemeter and detector in the actinometric region as well as in clinical and medical applications. (author)

  5. Quality assurance package for routine thermoluminescence dosimetry program

    International Nuclear Information System (INIS)

    Tawil, R.A.; Bencke, G.; Moscovitch, M.

    1988-01-01

    The Quality Assurance Package presented here specifies a set of reader-related hardware diagnostics and calibration procedures and automatically maintains audit trails of generated and derived thermoluminescence data. It specifies acceptable performance criteria for the reader and dosimeter assemblies; tracks and controls Readout Cycle Temperature Profiles; and ensures that the acquired data is verified. The quality of the generated glow curves is tracked by the real-time application of Computerized Glow Curve Deconvolution to reference dosimeters that may be mixed with field dosimeters during readout sessions. This package is supported by a menu-driven software system using vertical auto-selection menus, lotus-style horizontal menus, data entry menus with automatic error checking, and pop-up windows. The menu system is supported by an extensive HELP file; data EDITING is password-protected, and a journal is maintained for each editing session as part of the audit trail. Files for the Raw Data and Derived Dose results are maintained and managed in seven databases. The paper provides an in-depth analysis of each of the procedures, specifies data validation criteria, and presents samples of the reports generated

  6. Thermoluminescent dosimetry of critical organs in CT pediatric patients

    International Nuclear Information System (INIS)

    Azorin, Juan; Tabares, Musel

    2008-01-01

    This paper presents the determination of absorbed dose in critical organs of pediatric patients submitted to head computed tomography (CT) studies. This research included patients up to 16 years old submitted to head CT studies using a Siemens Somaton 16 plus multislice CT scanner. Doses were measured using locally made LiF: Mg,Cu,P + PTFE thermoluminescent dosimeters (TLD) due to its tissue equivalence and low fading. Results showed that both the organ absorbed doses and the volume computed tomography dose index (CTDI vol ) determined for simple studies were half of those obtained for contrasted studies. In the case of head three-dimensional reconstruction CT studies the CTDI vol value obtained was almost the same that the obtained for simple CT studies but the organ doses were significantly different. These results suggest that the CTDI vol value is a good indication for choosing the exposure parameters of the CT studies and is useful in the determination of the effective dose but it is not related with the organ doses. (author)

  7. Thermoluminescent characteristics of diopside-teflon composites for radiation dosimetry

    International Nuclear Information System (INIS)

    Melo, A.P.; Caldas, L.V.E.

    2006-01-01

    Diopside - Teflon composites were been studied in relation to their dosimetric properties for high-dose dosimetry. Diopside from Minas Gerais, Brazil, CaMg(Si 2 O 6 ), was obtained in form of rude mineral with inclusions of quartz. The samples were prepared and only Diopside grains obtained. Pellets of Diopside-Teflon composites were prepared in the proportion of 2(Teflon): 1 (Diopside).The TL response repeatability presented a maximum coefficient of variation of 7.5%. The calibration curve is linear between 0.5 Gy and 1 kGy. TL emission spectra present three emissions of similar intensities at 570 nm, 590 nm and between 610-635 nm. The results suggest that the material presents good characteristics for use as high-dose radiation detectors. (Author)

  8. Thermoluminescent dosimetry in dentistry students in radiological training

    International Nuclear Information System (INIS)

    Loya, M.; Duarte, R.; Montero, M.E.; Gonzalez, P.R.; Ojeda, S.L.; Sanin, L.H.

    2007-01-01

    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)

  9. In vivo thermoluminescent dosimetry on the radiotherapy of limphomas, esophageal and uterine tumour

    International Nuclear Information System (INIS)

    Morales, F.C.

    1982-01-01

    A comparative study between dose distribution in pre-selected tumoral plans was established through measurements with thermoluminescent dosimeters and calculations based on 'scatter-air-ratios' properties, isodose curves and collected data. Clinic dosimetry was performed 'in vivo' with LiF dosimeters (TLD-100) and LiF Teflon (1 mm theta, 6 mm lenght). Patients with Hodgkin's disease, carcinoma of the esophagus and of the uterine cervix were selected. Telecobaltherapy was used for these groups of neoplasic conditions. (M.A.C.) [pt

  10. Improvements in or relating to radio frequency heaters for thermoluminescent dosimetry discs

    International Nuclear Information System (INIS)

    Stephenson, R.

    1976-01-01

    A combination of radiofrequency heater adapted to receive thermoluminescent dosimetry discs, equipment for counting light emission from the discs, and a digital timer controlling both the heating time of the heater and the counting time of the counting equipment, is described. The heater includes a pair of power amplifiers arranged in push-pull configuration. A stabilised power supply is provided, with overload protection for the amplifiers, together with a control circuit arranged to maintain the power outputs of the amplifiers at a predetermined adjustable level. A variable frequency oscillator may be provided, together with driver stages for the amplifiers. (U.K.)

  11. Technical recommendations for the use of thermoluminescence for dosimetry in individual monitoring for photons and electrons from external sources

    International Nuclear Information System (INIS)

    1975-01-01

    The principles of thermoluminescence dosimetry and the role it may play in the field of personnel dosimetry are presented. Technical recommendations are made as an indication of what is generally regarded as good practice and they are intended to be of assistance in avoiding the common sources of error. Errors due to: the detector; the evaluation procedure; the thermal treatment; at the sensitivity of the detector to neutrons. The recommendations are concerned with: the choice of detector material; design of thermoluminescent dosemeters; read-out procedure; reader; handling procedures; dose evaluations; automation; documentation and data handling

  12. Characterization of thermoluminescent response of Al2O3:Tm/Teflon for gamma rays dosimetry

    International Nuclear Information System (INIS)

    Carvalho Junior, Alvaro B. de; Barros, Vinicius S.M. de; Elihimas, Diego Rafael M.; Khoury, Helen J.; Azevedo, Walter M. de

    2011-01-01

    In this work, α-Al 2 O 3 doped with Tm 3+ was prepared by combustion synthesis techniques for thermoluminescent (TL) ionizing radiation dosimetry applications. After this, Al 2 O 3 :Tm (0.1%) pellets were manufactured from a 2:1 homogeneous mixture of Al 2 O 3 :Tm (0.1%) and powdered Teflon (PTFE). Ten pellets were used to characterize the dosimetric properties. The dosimetric characterization was performed by analyses of the reproducibility, sensitivity of the TL response vs. dose between 1 and 10 Gy to 60 Co source and fading. The results showed a glow curve with a peak near to 225 deg C, a linear TL response with the gamma radiation dose in the range investigated and a reproducibility < 10%. These results indicate a potential use of these pellets for gamma radiation dosimetry. (author)

  13. Thermoluminescent properties of ZrO2:Mn for UV light dosimetry

    International Nuclear Information System (INIS)

    Rivera M, T.; Azorin N, J.; Falcony G, C.; Martinez, E.; Garcia, M.

    1999-01-01

    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 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)

  14. Thermoluminescence and applications

    International Nuclear Information System (INIS)

    Rodrigues, G.V.

    1986-01-01

    The theory of thermoluminescent emission, the characteristics of main thermoluminescent phosphorus, and some applications are presented. The main thermoluminescent dosemeters used in dosimetry are related. (M.C.K.)

  15. Thermoluminescence and their applications

    International Nuclear Information System (INIS)

    Rodrigues, G.V.

    1986-01-01

    The theory involved in the phenomenon of thermoluminescence emission, the characteristics of the main thermoluminescent phosphorus and some of their applications are presented. Some of the main thermoluminescent dosemeters used in dosimetry are described. (M.C.K.) [pt

  16. Thermoluminescent dosimetry of ionizing radiations using ZrO2 prepared at low temperatures

    International Nuclear Information System (INIS)

    Rivera M, T.; Diaz G, J.A.I.; Olvera T, L.; Azorin N, J.; Barrera S, M.; Soto E, A.M.

    2005-01-01

    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 2 -a). The structural characteristics of ZrO 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 2 -a, previously irradiated with beta particles of 90 Sr/ 90 Y, they presented a thermoluminescent curve with two peaks at 150 and 260 C. The fading of the information of the one ZrO 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)

  17. An evaluation of the Panasonic model UD513AC-1 Thermoluminescence Dosimetry system

    International Nuclear Information System (INIS)

    Durrer, R.E. Jr.

    1991-12-01

    An evaluation of the Panasonic UD513AC-1 Thermoluminescence Dosimetry system was performed to determine the system's capabilities as a general purpose thermoluminescence dosimeter measuring device. The tests that were performed included a critique of the user's manual, delimitation of the operating parameters, the quality of construction, and an evaluation of the features that were unique to this system. The UD513AC-1 was found to be an adequate measuring device for most dosimetric applications. It was not well suited for experimental work with thermoluminescence materials due to a low sensitivity displayed by the photomultiplier tube to commonly used materials. The system was well constructed and did not suffer hardware failure during this research. Major attributes of the UD513AC-1 were automatic data storage, highly reproducible heating ramps, an excellent infrared light filter and a unique feature to a single phosphor unit, a dose determination function. Negative aspects of the system included a limited data manipulation capability within the controlling program, a poorly written user's manual, inadequate sensitivity on the part of the photomultiplier tube, and insufficient capability to adjust the hot N 2 gas flow to desired levels

  18. Developing an optimum protocol for thermoluminescence dosimetry with gr-200 chips using Taguchi method

    International Nuclear Information System (INIS)

    Sadeghi, Maryam; Faghihi, Reza; Sina, Sedigheh

    2017-01-01

    Thermoluminescence dosimetry (TLD) is a powerful technique with wide applications in personal, environmental and clinical dosimetry. The optimum annealing, storage and reading protocols are very effective in accuracy of TLD response. The purpose of this study is to obtain an optimum protocol for GR-200; LiF: Mg, Cu, P, by optimizing the effective parameters, to increase the reliability of the TLD response using Taguchi method. Taguchi method has been used in this study for optimization of annealing, storage and reading protocols of the TLDs. A number of 108 GR-200 chips were divided into 27 groups, each containing four chips. The TLDs were exposed to three different doses, and stored, annealed and read out by different procedures as suggested by Taguchi Method. By comparing the signal-to-noise ratios the optimum dosimetry procedure was obtained. According to the results, the optimum values for annealing temperature (de.C), Annealing Time (s), Annealing to Exposure time (d), Exposure to Readout time (d), Pre-heat Temperature (de.C), Pre-heat Time (s), Heating Rate (de.C/s), Maximum Temperature of Readout (de.C), readout time (s) and Storage Temperature (de.C) are 240, 90, 1, 2, 50, 0, 15, 240, 13 and -20, respectively. Using the optimum protocol, an efficient glow curve with low residual signals can be achieved. Using optimum protocol obtained by Taguchi method, the dosimetry can be effectively performed with great accuracy. (authors)

  19. Thermoluminescence dosimetry and its applications in medicine. Part 2: history and applications

    International Nuclear Information System (INIS)

    Kron, T.

    1995-01-01

    Thermoluminescence dosimetry (TLD) has been available for dosimetry of ionising radiation for nearly 100 years. The variety of materials and their different physical forms allow the determination of different radiation qualities over a wide range of absorbed dose. This makes TL dosimeters useful in radiation protection where dose levels of μ Gy are monitored as well as in radiotherapy where doses up to several Gray are to be measured. The major advantages of TL detectors are their small physical size and that no cables or auxiliary equipment is required during the dose assessment. TLD is considered to be a good method for point dose measurements in phantoms as well as for in vivo dosimetry on patients during radiotherapy treatment. As an integrative dosimetric technique, it can be applied to personal dosimetry and it lends itself to the determination of dose distributions due to multiple or moving radiation sources (e.g. conformal and dynamic radiotherapy, computed tomography). In addition, TL dosimeters are easy to transport, and they can be mailed. This makes them well suited for intercomparison of doses delivered in different institutions. The present article aims at describing the various applications TLD has found in medicine by taking into consideration the physics and practice of TLD measurements which have been discussed in the first part of this review. 198 refs., 4 tabs., 2 figs

  20. Eu"2"+ doped TiO_2 nano structures synthesized by HYSYCVD for thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Perez A, J. A.; Leal C, A. L.; Melendrez A, R.; Barboza F, M.

    2016-10-01

    Titania (TiO_2) has attracted interest owing his potential applications as dosimetry material given his excellent optical, electrical and thermal properties and the ability to shape his structure make TiO_2 suitable for research and dosimetry applications. In this work, a systematic study to know the magnitude of processing parameters influence on thermoluminescent properties of undoped (TiO_2) and doped (TiO_2:Eu"2"+) nano materials obtained by hybrid precursor systems chemical vapor deposition (HYSYCVD) technique is presented. Synthesis of one dimension nano structures of TiO_2:Eu"2"+ was carried out using K_2TiF_6 and EuCl_2 as dopant at 0.5, 1, 2.5 and 5 wt %. The nano structures samples were irradiated with β-ray in a doses range of 0.083-3000 Gy. All thermoluminescence (Tl) glow curves showed 3 broad Tl peaks around 373, 473 and 573 K, and a dosimetric linear behavior from 0.083 to 300 Gy. The Tl has a good reproducibility, with deviations of around 5%, making these TiO_2:Eu"2"+ nano materials suitable for dosimetric applications. (Author)

  1. Treatment verification and in vivo dosimetry for total body irradiation using thermoluminescent and semiconductor detectors

    International Nuclear Information System (INIS)

    Oliveira, F.F.; Amaral, L.L.; Costa, A.M.; Netto, T.G.

    2014-01-01

    The objective of this work is the characterization of thermoluminescent and semiconductor detectors and their applications in treatment verification and in vivo dosimetry for total body irradiation (TBI) technique. Dose measurements of TBI treatment simulation performed with thermoluminescent detectors inserted in the holes of a “Rando anthropomorphic phantom” showed agreement with the prescribed dose. For regions of the upper and lower chest where thermoluminescent detectors received higher doses it was recommended the use of compensating dose in clinic. The results of in vivo entrance dose measurements for three patients are presented. The maximum percentual deviation between the measurements and the prescribed dose was 3.6%, which is consistent with the action level recommended by the International Commission on Radiation Units and Measurements (ICRU), i.e., ±5%. The present work to test the applicability of a thermoluminescent dosimetric system and of a semiconductor dosimetric system for performing treatment verification and in vivo dose measurements in TBI techniques demonstrated the value of these methods and the applicability as a part of a quality assurance program in TBI treatments. - Highlights: • Characterization of a semiconductor dosimetric system. • Characterization of a thermoluminescent dosimetric system. • Application of the TLDs for treatment verification in total body irradiation treatments. • Application of semiconductor detectors for in vivo dosimetry in total body irradiation treatments. • Implementation of in vivo dosimetry as a part of a quality assurance program in radiotherapy

  2. Thermoluminescence dosimetry in very hot atmosphere with a view to the dosimetry in nuclear reactors

    International Nuclear Information System (INIS)

    Bikwaku, Nsampala Tomakunsimba

    1985-01-01

    In order to develop radiation resistant materials for use in the region of nuclear reactor cores, it is necessary to know the dose absorbed by the surrounding structures. A passive thermoluminescence technique was chosen, an activated alumina material with very deep traps which are stable at high temperature (450 deg. C), being used. The characteristic properties of this detector have been studied and an attempt made to interpret the results obtained. (author) [fr

  3. Dose measurements in dental radiology using thermoluminescent dosimetry;Medicoes de dose em radiodiagnostico odontologico utilizando dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Chiara, Ana Claudia M. de; Costa, Alessandro M. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras; Pardini, Luiz Carlos [Universidade de Sao Paulo (FORP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Odontologia

    2009-07-01

    The aim of this work was the implementation of a code of practice for dosimetry in dental radiology using the technique of thermoluminescent dosimetry. General principles for the use of thermoluminescent dosimeters were followed. The irradiations were performed using ten X-ray equipment for intra-oral radiography and an X-ray equipment for panoramic radiography. The incident air kerma was evaluated for five different exposure times used in clinical practice for intra-oral radiographs. Using a backscatter factor of 1.2, it was observed that approximately 40% of the entrance skin dose values found for intra-oral radiographs are above the diagnostic reference level recommended in national regulation. Different configurations of voltage and current were used representing the exposure as a child, woman and man for panoramic radiographs. The results obtained for the air kerma area product were respectively 53.3 +- 5.2 mGy.cm{sup 2}, 101.5 +- 9.5 mGy.cm{sup 2} and 116.8 +- 10.4 mGy.cm{sup 2}. The use of thermoluminescent dosimetry requires several procedures before a result is recorded. The use of dosimeters with ionization chambers or semiconductors provides a simple and robust method for routine measurements. However, the use of thermoluminescent dosimetry can be of great value to large-scale surveys to establish diagnostic reference levels. (author)

  4. Evaluation of thermoluminescent dosimeters using water equivalent phantoms for application in clinical electrons beams dosimetry

    International Nuclear Information System (INIS)

    Bravim, Amanda

    2010-01-01

    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 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 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 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)

  5. Preparation and thermoluminescent dosimetry features of high sensitivity LiF:Mg,Ce phosphor

    Science.gov (United States)

    Shoushtari, M. K.; Zahedifar, M.; Sadeghi, E.

    2018-04-01

    Thermoluminescence (TL) kinetics and dosimetry features of newly produced LiF doped with Mg and Ce were investigated. Different contents of Mg (0-1 mol%) and Ce (0-2 mol%) were introduced in host material by melting method. The most TL sensitivity of the fabricated phosphor was obtained at 0.7 and 0.05 mol% concentrations of Mg and Ce impurities, respectively. The optimum pre-irradiation annealing regime of the synthesized LiF-based material was found at 350 °C for 10 min. Kinetic parameters of LiF:Mg,Ce dosimeter were obtained using different methods of computerized glow curve deconvolution (CGCD), initial rise (IR) and isothermal decay (ID). A good conformity are observed between the results obtained from different kinetic analysis methods. Other TL features such as fading, dose response and reusability were also examined.

  6. Thermoluminescence of metal oxides and its applications to the dosimetry of low energy ionizing radiation

    International Nuclear Information System (INIS)

    Azorin N, J.; Rivera M, T.; Falcony G, C.; Martinez S, E.; Garcia H, M.

    1999-01-01

    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 2 films without doping and doped with Eu, Tb, and Mn as well as Al 2 O 3 films without doping and doped with Na. The results obtained to the irradiated films of ZrO 2 with ultraviolet and visible lights have been satisfactory. The Al 2 O 3 in film form showed to be a promising material for the measuring ultraviolet light and the pellets of ZrO 2 + Ptfe for X-rays and low energy gamma rays. (Author)

  7. Investigation of thermoluminescence properties of mobile phone screen displays as dosimeters for accidental dosimetry

    Science.gov (United States)

    Mrozik, Anna; Marczewska, B.; Bilski, P.; Kłosowski, M.

    2014-11-01

    The rapid assessment of the radiation dose after unexpected exposure is a task of accidental dosimetry. In case of a radiological accident glasses originating from mobile phone screens, placed usually near the human body, could be used as emergency thermoluminescent (TL) personal dosimeters. The time between irradiation and TL readout is crucial and therefore preparation of the mobile phone screens and their readout conditions should be optimized. The influence of the samples etching, bleaching and selection of the optical filters based on measurement of the emission spectrum of irradiated glass samples during heating for different types of mobile phones were the subjects of our investigation. Obtained results showed that glasses extracted from different brands of mobile phones have different dosimetric properties but all of them give a luminescent signal which can be used to calculate the dose.

  8. Comparisons between direct ion storage and thermoluminescence dosimetry individual monitoring systems, and internet reporting

    International Nuclear Information System (INIS)

    Kiuru, A.; Kahilainen, J.; Hyvoenen, H.; Vartiainen, E.

    2001-01-01

    A new electronic direct ion storage (DIS) dosemeter allows accumulated personal dose equivalent H p (d) at depths of 10 mm and 0.07 mm to be monitored in a few seconds by inserting the dosemeter into a local reader without deleting the accumulated dose. The DIS system meets general requirements on individual monitoring of hospital personnel using ionising radiation. It differs greatly from off-line thermoluminescence dosimetry systems and offers many additional benefits. The non-volatile reading takes only 5 s, is taken as often as needed, and the data are collected into a dose database, where background radiation is subtracted. Individual personnel doses are reported in Intranet as well as on the Internet at regular intervals to the National Regulatory Authorities. (author)

  9. Thermoluminescence of chip inductors from mobile phones for retrospective and accident dosimetry

    International Nuclear Information System (INIS)

    Fiedler, I.; Woda, C.

    2011-01-01

    Electronic components in portable electronic devices such as mobile phones and portable media player have previously been shown to be useful tools for retrospective and accident dosimetry. In this study the properties of alumina rich inductors removed from mobile phones are investigated using thermoluminescence (TL). The typical glow curve of this component has two main peaks at 170 and 270 °C. With a suitable measurement protocol sensitivity changes of both peaks could be corrected so that the TL signal shows a linear increase in the investigated dose range from 100 mGy to 5 Gy. All inductors studied showed essentially no signal for zero dose. We investigated the fading of the TL signals and the detection limit of inductors extracted from different mobile phones.

  10. Developing an Optimum Protocol for Thermoluminescence Dosimetry with GR-200 Chips using Taguchi Method.

    Science.gov (United States)

    Sadeghi, Maryam; Faghihi, Reza; Sina, Sedigheh

    2017-06-15

    Thermoluminescence dosimetry (TLD) is a powerful technique with wide applications in personal, environmental and clinical dosimetry. The optimum annealing, storage and reading protocols are very effective in accuracy of TLD response. The purpose of this study is to obtain an optimum protocol for GR-200; LiF: Mg, Cu, P, by optimizing the effective parameters, to increase the reliability of the TLD response using Taguchi method. Taguchi method has been used in this study for optimization of annealing, storage and reading protocols of the TLDs. A number of 108 GR-200 chips were divided into 27 groups, each containing four chips. The TLDs were exposed to three different doses, and stored, annealed and read out by different procedures as suggested by Taguchi Method. By comparing the signal-to-noise ratios the optimum dosimetry procedure was obtained. According to the results, the optimum values for annealing temperature (°C), Annealing Time (s), Annealing to Exposure time (d), Exposure to Readout time (d), Pre-heat Temperature (°C), Pre-heat Time (s), Heating Rate (°C/s), Maximum Temperature of Readout (°C), readout time (s) and Storage Temperature (°C) are 240, 90, 1, 2, 50, 0, 15, 240, 13 and -20, respectively. Using the optimum protocol, an efficient glow curve with low residual signals can be achieved. Using optimum protocol obtained by Taguchi method, the dosimetry can be effectively performed with great accuracy. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. The Radio-thermoluminescence of CaSO{sub 4}:Sm and Its Use in Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bjaerngard, Bengt

    1964-12-15

    The general properties of the thermoluminescence of CaSO{sub 4}:Sm have been investigated. The luminescent emission lies in the region 4,000 - 6,200 A with narrow bands at 5,600 and 5,900 A. The glow curve has the main peak at 400 deg C and a smaller one at 95 deg C. The fading of the thermoluminescence signal in the former peak is negligible at temperatures up to 200 deg C. The light yield of the 400 deg C emission is 0.3 % at small exposures and increases to 1.5 % at 10,000 R. Saturation occurs at about 30,000 R. The variation of the sensitivity is interpreted as being caused by a generation of new traps. It is concluded that CaSO{sub 4}:Sm provides a good basis for gamma dosimetry at high temperatures. It can be used up to somewhat above 200 deg C without corrections for the influence of the irradiation temperature. It may be used up to 300 deg C if the exposure times are restricted and corrections are applied. Because of the high readout temperature needed, the emission of incandescent light is a severe background component. The system described cannot be used for the determination of exposures less than about one roentgen.

  12. Technical requirements for implementation of an individual monitoring service for evaluation of operational quantity HP(10) using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Francisco, Adelaide Benedita Armando

    2016-01-01

    This work aims to establish technical requirements for the development of a TLDs system for the assessment of operational quantity H 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)

  13. A practical and transferable methodology for dose estimation in irradiated spices based on thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    D'Oca, M.C.; Bartolotta, A.; Cammilleri, C.; Giuffrida, S.; Parlato, A.; Di Stefano, V.

    2008-01-01

    Full text: Among the industrial applications of ionizing radiation, the treatment of food for preservation purposes is a worldwide recognized tool, provided that proper and validated identification methods are available and used. The thermoluminescence (TL) dosimetry is the physical method validated by the European Committee for Standardization for food from which silicate minerals can be isolated, such as spices and aromatic herbs. The aim of this work was to set up a reasonably simple procedure, alternative to the recommended one, for the identification of irradiated spices and to estimate at the same time the original dose in the irradiated product, using TL and the additive dose method, even after months storage. We have already shown that the additive dose method can be applied with TL dosimetry, if the TL response of the silicate specimen after extraction is always added to the response after each irradiation; the applied added doses were higher than 1 kGy, that can however give saturation problems. The new proposed methodology makes use of added doses lower than 600 Gy; the entire process can be completed within few hours and a linear fit can be utilized. The method was applied to the silicates extracted from oregano samples soon after the radiation treatment (original dose: 2 - 3 - 5 kGy), and after one year storage at room conditions in the dark (original dose: 1-2 kGy). The procedure allows the identification of irradiated samples, without any false positive, together with an estimation of the dose range

  14. In vivo dosimetry with thermoluminescent dosimeters in radiotherapy: entrance and exit doses

    International Nuclear Information System (INIS)

    Alves, C.; Lopes, M.C.

    2000-01-01

    In vivo dosimetry, by entrance and exit dose measurements, is a vital part of a radiotherapy quality assurance program. The uncertainty associated with dose delivery is internationally accepted to be within 5% or inferior depending on the tumor pathology. Thermoluminescent dosimetry is one of the dosimetric techniques used to verify the agreement between delivered and prescribed doses. Nevertheless, it requires a very accurate calibration methodology. We have used LiF chips (4.5 mm diameter and 0.8 mm thick) calibrated towards a PTW ionization chamber of 0.3 cc, in three photon energies: Co-60, 4 and 6 MeV. The TLD reader used was a Rialto 688 from NE Technology and the annealing oven the Eurotherm type 815. The calibration methodology relies on the experimental determination of individual correction factors and on a correction factor derived from a control group of dosimeters. The exit and entrance dose measurements are performed in quite different situations. To be able to achieve those two quantities with TLD, these should be independently calibrated according to the measurement conditions. Alternatively, we can use a single calibration, in entrance dose, and convert the result to the exit dose value by introducing some correction factors. These corrections are related to the different measurement depths and to the different backscattering contributions. We have proved that within an acceptable error we can perform a single calibration and adopt the correction factors which are energy and field size dependent. (author)

  15. Thermoluminescence kinetics in materials exposed to the low doses applicable to dating and dosimetry

    International Nuclear Information System (INIS)

    Levy, P.W.

    1984-11-01

    Thermoluminescence (TL) kinetics have been investigated for low dose situations applicable to dating, dosimetry, and recent geological deposits. Studied were the general one-trap kinetic equation, which reduces to the well known 1st and 2nd order kinetic equations when various assumptions apply, and the interactive kinetic equations, which describes TL in materials exhibiting more than one glow peak. In materials with one glow peak area varies linearly with dose; however, peak height is not linear with dose unless the TL obeys 1st order kinetics at all doses. In materials with two or more glow peaks neither peak height nor peak area varies linearly with dose, except in special situations. In fact, many peak height vs dose curves will be supralinear with the initial low-slope region occurring at relatively low doses. These considerations indicate: (1) Dating and dosimetry technique based on assumed linear peak height vs dose curves will usually underestimate the accumulated dose. (2) Dating techniques can be improved and/or made more reliable by determining the TL kinetics of the glow peaks measured

  16. Report of the Intercomparison program by thermoluminescent dosimetry for Secondary Standard Dosimetry Laboratories

    International Nuclear Information System (INIS)

    Papadopulos, Susana

    2000-01-01

    In this report the results of an intercomparison program within a research coordinated program are presented. This is a third phase of the study that consisted in to evaluate the implementation of the new ICRU quantities for individual monitoring by the SSDLs, their capabilities to perform irradiations in different angles and the interpretation of the standard ISO 4370-3. This phase as well the first one was coordinated by Argentina through the Autoridad Regulatoria Nuclear that verified the performance of the participant laboratories. The SSDL of Argentina calibrated the dosimetric system to be used, and sent a set of tld dosimeters for irradiation at the SSDL or dosimetry laboratories of nine countries of latin america

  17. Investigation and measurement of radio thermoluminescence properties of some calci tic mollusc shells of the Persian Gulf and the Oman Sea (for γ radiation dosimetry)

    International Nuclear Information System (INIS)

    Ghafourian, H.; Rabbani, M.; Rouhi, U.

    2000-01-01

    Biogenic Calcium Carbonate, particularly as naturally thermoluminescent calci tic mollusc shells may serve as excellent radio thermoluminescent dosimeters. In this study the radio thermoluminescence properties of 8 different bivalves of the Persian Gulf, the Oman Sea and the internal calcite shell of Sepia sp. are investigated. The results of this investigation have shown that the shells of Sepia sp., Pinctata radiata and Card ita bicolor as appropriate dosimeters for both personal and industrial dosimetry purposes, among which Sepia sp. is the most sensitive one. Callista umbonella and Mactra sp. are relatively less thermoluminescent while Saccostrea Cucullata and Chlamys ruschenbergerii are completely inert with respect to γ - thermoluminescence. Thermoluminescence properties of Anadara refescens and Anadara secticostata decrease surprisingly by an increase in the absorbed dose of γ radiation, which can mainly be interpreted as the result of crystal lattice destruction caused by ionizing radiation

  18. Thermoluminescence characteristics of Israeli household salts for retrospective dosimetry in radiological events

    Energy Technology Data Exchange (ETDEWEB)

    Druzhyna, S. [Department of Nuclear Engineering, Ben-Gurion University, 84105 Beer Sheva (Israel); Datz, H. [Radiation Safety Division, Soreq Nuclear Research Center, 81800 Yavne (Israel); Horowitz, Y.S. [Physics Department, Ben Gurion University, 84105 Beer Sheva (Israel); Oster, L., E-mail: leonido@sce.ac.il [Physics Unit, Sami Shamoon College of Engineering, 84100 Beer Sheva (Israel); Orion, I. [Department of Nuclear Engineering, Ben-Gurion University, 84105 Beer Sheva (Israel)

    2016-06-15

    Highlights: • Examination the potential use of Israeli household salt as a retrospective dosimeter. • Detailed investigation of the basic dosimetric characteristics of the salts. • It is shown that computerized glow curve analysis for accurate background subtraction and dose measurement is required. - Abstract: Following a nuclear accident or terror attack involving the dispersal of radioactive substances, radiation dose assessment to first responders and the members of the public is essential. The need for a retrospective assessment of the radiation dose to those possibly affected is, therefore, obligatory. The present study examines the potential use of Israeli household salt as a retrospective dosimeter (RD). The experiments were carried out on Israeli salt samples (NaCl) following a Nielsen market track survey based on scanning data representing the barcoded market, including organized and independent retail chains and a sample of private minimarkets and supermarkets. The technique used was thermoluminescence (TL) dosimetry. Salt samples were exposed to levels of dose from 0.5 mGy to 300 Gy at the Israeli Secondary Standard Dosimetry Laboratory of the Soreq Nuclear Research Center using a calibrated {sup 137}Cs source. Our emphasis has been on a detailed investigation of the basic dosimetric characteristics of the salts including: (i) glow curve analysis (ii) individual glow peak dose response (iii) reproducibility (iv) estimation of minimal measurable dose (v) effect of nitrogen readout, (vi) influence of humidity during pre-irradiation storage and (vii) light induced fading. The results are sufficiently favorable to lead to the conclusion that the Israeli household salts can serve as a pragmatic potential candidate for RD under certain restricted conditions. Occasional pre-calibration of the major salt brands in a dedicated laboratory may be essential depending on the required accuracy in the estimation of dose and consequent clinical evaluation.

  19. Thermoluminescence characteristics of Israeli household salts for retrospective dosimetry in radiological events

    International Nuclear Information System (INIS)

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

    2016-01-01

    Highlights: • Examination the potential use of Israeli household salt as a retrospective dosimeter. • Detailed investigation of the basic dosimetric characteristics of the salts. • It is shown that computerized glow curve analysis for accurate background subtraction and dose measurement is required. - Abstract: Following a nuclear accident or terror attack involving the dispersal of radioactive substances, radiation dose assessment to first responders and the members of the public is essential. The need for a retrospective assessment of the radiation dose to those possibly affected is, therefore, obligatory. The present study examines the potential use of Israeli household salt as a retrospective dosimeter (RD). The experiments were carried out on Israeli salt samples (NaCl) following a Nielsen market track survey based on scanning data representing the barcoded market, including organized and independent retail chains and a sample of private minimarkets and supermarkets. The technique used was thermoluminescence (TL) dosimetry. Salt samples were exposed to levels of dose from 0.5 mGy to 300 Gy at the Israeli Secondary Standard Dosimetry Laboratory of the Soreq Nuclear Research Center using a calibrated 137 Cs source. Our emphasis has been on a detailed investigation of the basic dosimetric characteristics of the salts including: (i) glow curve analysis (ii) individual glow peak dose response (iii) reproducibility (iv) estimation of minimal measurable dose (v) effect of nitrogen readout, (vi) influence of humidity during pre-irradiation storage and (vii) light induced fading. The results are sufficiently favorable to lead to the conclusion that the Israeli household salts can serve as a pragmatic potential candidate for RD under certain restricted conditions. Occasional pre-calibration of the major salt brands in a dedicated laboratory may be essential depending on the required accuracy in the estimation of dose and consequent clinical evaluation.

  20. Intrinsic dosimetry. Properties and mechanisms of thermoluminescence in commercial borosilicate glass

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Richard A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-10-01

    Intrinsic dosimetry is the method of measuring total absorbed dose received by the walls of a container holding radioactive material. By considering the total absorbed dose received by a container in tandem with the physical characteristics of the radioactive material housed within that container, this method has the potential to provide enhanced pathway information regarding the history of the container and its radioactive contents. The latest in a series of experiments designed to validate and demonstrate this newly developed tool are reported. Thermoluminescence (TL) dosimetry was used to measure dose effects on raw stock borosilicate container glass up to 70 days after gamma ray, x-ray, beta particle or ultraviolet irradiations at doses from 0.15 to 20 Gy. The TL glow curve when irradiated with 60Co was separated into five peaks: two relatively unstable peaks centered near 120 and 165°C, and three relatively stable peaks centered near 225, 285, and 360°C. Depending on the borosilicate glass source, the minimum measurable dose using this technique is 0.15-0.5 Gy, which is roughly equivalent to a 24 hr irradiation at 1 cm from a 50-165 ng source of 60Co. Differences in TL glow curve shape and intensity were observed for the glasses from different geographical origins. These differences can be explained by changes in the intensities of the five peaks. Electron paramagnetic resonance (EPR) and multivariate statistical methods were used to relate the TL intensity and peaks to electron/hole traps and compositional variations.

  1. Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors

    International Nuclear Information System (INIS)

    Toivonen, M.

    1991-08-01

    The thesis presents criteria for thermoluminescence dosimetry systems suitable for precision measurements and, moreover, a detailed examination of the sources of systematic and random error. Instructions are given for annealing processes, calibration procedures, quality control, and operational rules, which are necessary in modem TLD. The performances of some principally different systems are compared. The old LiF-powder-based TLD system, with an overall uncertainty of measurement of about 1.6 percent for ten repeated readouts and for irradiations under calibration conditions with Co-60, is still the best but a comparable, although slightly lower, accuracy of about 1.7 percent can be reached more conveniently with solid LiF detectors. In measurements where absolute system calibration is not of interest (i.e., in depth-dose curve measurements, etc.), the advantages of the simple powder-based system are even more concrete. An integrated TLD process is presented for progressive utilization of automation in precision measurements. The sources of random error and unknown systematic error in current readout instruments are examined. Mechanical tolerances in critical parts of the readout instruments are thought to be the reason why the method of heating with hot gas has not been superior with respect to the precision of measurements, in spite of the excellent repeatability of the glow curve shape observed for successive readouts

  2. As the thermoluminescent dosimetry can help in the quality control in radiotherapy

    International Nuclear Information System (INIS)

    Araujo, Anna Maria Campos de; Marin, Alfredo Viamonte; Viegas, Claudio C.B.; Souza, Roberto Salomon de; Alves, Victor Gabriel Leandro

    2011-01-01

    According to the international (International Atomic Energy Agency) and national (Agencia Nacional de Vigilancia Sanitaria- ANVISA) rules, the irradiators of any radiotherapy department should be periodical/y checked through a quality control external audit. In Brazil, where we have about 300 radiotherapy equipment, is very difficult to perform these audits on site with a acceptable frequency. For this reason, the Quality Service on Ionizing Radiations from the National Cancer Institute-INCA/Rio de Janeiro, developed and implemented postal systems to evaluate the main parameters of the radiotherapeutic equipment (Co-60, linear accelerators and high dose rate brachytherapy). All the postal systems developed are based on thermoluminescent dosimeters. The aim of this paper is to share the INCA experience in the use of TLD for dose evaluation and quality control measurements. Following the same philosophy, INCA developed also a postal system to evaluate the doses in mammography, since Brazil has 4000 equipment and performs about 8 millions of mammograms per year. A new experience is studying the OSL dosimeters to be used also for dose evaluation, including for in vivo dosimetry. (author)

  3. Investigation of thermoluminescence properties of mobile phone screen displays as dosimeters for accidental dosimetry

    International Nuclear Information System (INIS)

    Mrozik, Anna; Marczewska, B.; Bilski, P.; Kłosowski, M.

    2014-01-01

    The rapid assessment of the radiation dose after unexpected exposure is a task of accidental dosimetry. In case of a radiological accident glasses originating from mobile phone screens, placed usually near the human body, could be used as emergency thermoluminescent (TL) personal dosimeters. The time between irradiation and TL readout is crucial and therefore preparation of the mobile phone screens and their readout conditions should be optimized. The influence of the samples etching, bleaching and selection of the optical filters based on measurement of the emission spectrum of irradiated glass samples during heating for different types of mobile phones were the subjects of our investigation. Obtained results showed that glasses extracted from different brands of mobile phones have different dosimetric properties but all of them give a luminescent signal which can be used to calculate the dose. - Highlights: • Application of acids mixture for more effective glass samples etching. • Bleaching can be performed not only by blue but also by UV light. • The readout with BG39 optical filter improves the TL signal intensity. • The glass samples from touch mobile phones are worse emergency TL dosimeters

  4. State of the art in thermoluminescent dosimetry using dosemeters with automated read-out

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1979-01-01

    In the beginning, the results obtained with automated read-out TLD have been quite disappointing, both for manufacturers and users. In response to this, industry then seeked advice and assistance from those experienced in the practical use of dosemeters, and the development of the second generation of automated TLD has been a common task of manufacturers and purchosers. As a preliminary achievement of development work along this line, a dosemeter has been presented by a Japanese manufacturer, meeting the requirements in quite a satisfactory way. The device is characterized by a frequency of disturbance of -5 , a microprocessor for controlling the measuring and control functions, possibility of active input of device parameters and boundary conditions, extensive self-control of operating functions, complete data protection, and thin-film detector technique. Pursuing this line of development, and taking into account future recommentations, automated thermoluminescent dosimetry does seem to be a promising alternative to current measuring techniques in personnel monitoring. (orig./RW) [de

  5. Physical properties and thermoluminescence of glasses designed for radiation dosimetry measurements

    International Nuclear Information System (INIS)

    Laopaiboon, R.; Bootjomchai, C.

    2015-01-01

    Highlights: • TL stability of soda-lime glass was corrected by dopants. • D LDL values indicated that the glass samples have good radiation sensitivity. • Bond compression model theory was used to confirm the results from experimental. • High elastic moduli of glass samples indicated that high stability of structure. - Abstract: Soda lime glasses doped with CeO 2 , Nd 2 O 3 and MnO 2 were prepared. Thermoluminescence (TL) properties, such as glow curves and linearity of TL response on irradiation dose were investigated. Results showed that the TL properties depended on the type and concentration of the dopants. Samples were selected to calculate energy trap depth parameters. To design materials for radiation dosimetry, physical properties, ion concentration, elastic properties and effective atomic numbers are important. Theoretical bond compression models were used to determine the elastic moduli for comparison with experimental values. Results show fair agreement between theoretical and experimental measurements. The high elastic moduli of the glass samples indicated high rigidity and stability of the glass matrix structure

  6. Thermoluminescence dosimetry applied to quality assurance in radiotherapy, brachytherapy and radiodiagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Marinello, G [Centre Hospitalo-Universitaire, Creteil (France). Dept. Inter-Hospitalier de Cancerologie

    1996-08-01

    Thermoluminescence (TL) dosimetry is very interesting for in vivo measurements because TL detectors have the advantages of being very sensitive under a very small volume and do not meet to be connected to an electrometer with an unwieldy cable. The principle of the method being briefly recalled, criteria of choice of a TL material according to the applications to be performed are given. It is shown that to be used for in vivo measurements, TL material should have the same response at room and patient temperatures and be equivalent to soft tissue, lungs or bones for the energy ranges encountered in practice. Theoretical data are provided in order to facilitate the user`s choice. The different heating processes (linear or isothermal heating kinetics, hot gas, etc.) and light detection systems of TL readers are also presented. TL manual and automatic readers commercially available in 1994, and the emission temperature and wavelength the dosimetric peaks of usual TL materials are presented in two tables, respectively. Then the principal properties of TL dosimeters to be used for in vivo measurements and their practical consequences are summarized: signal stability after irradiation, intrinsic precision, sensitivity, response with dose, dose-rate, mass and energy. At last some examples of applications as different as total body and skin irradiations, brachytherapy, diagnostic radiology and quality assurance purposes are given. (author). 35 refs, 6 figs, 4 tabs.

  7. Thermoluminescence of glass display from mobile phones for retrospective and accident dosimetry

    International Nuclear Information System (INIS)

    Discher, M.; Woda, C.

    2013-01-01

    This paper deals with the thermoluminescence (TL) study of glass displays from mobile phones with the aim to use them as emergency dosimeters after an accident involving ionizing radiation. Dosimetric properties are analysed in order to examine and to critically evaluate the usability. Tests are carried out regarding the characterization of the radiation induced TL signal and the zero dose signal (intrinsic background) on a variety of display samples. Investigations on the thermal and optical stability of TL signals are carried out. The detection limit is mainly determined by the variability of the zero dose signal and lies in the range of 300–400 mGy. A linear relationship between the measured TL signal and the applied dose is observed for doses between 10 mGy and 20 Gy. A measurement protocol for the detection of absorbed radiation dose is developed, considering the experimental dosimetric properties. A reconstruction of the absorbed dose is possible using glass samples from mobile phones, if the signal loss due to storage and optical bleaching of the TL signal is adequately corrected for. This was confirmed by realistic tests. - Highlights: • Glass displays of mobile phones have potential for retrospective dosimetry. • Signal fading can be corrected with an universally fading curve. • Irradiation trials on intact mobile phones demonstrated a reasonable agreement between given and measured dose

  8. Thermoluminescence characteristics of different dimensions of Ge-doped optical fibers in radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Begum, M.; Mizanur R, A. K. M.; Abdul R, H. A.; Yusoff, Z. [Multimedia University, Faculty of Engineering, 63100 Cyberjaya, Selangor Darul Ehsan (Malaysia); Begum, M. [Bangladesh Atomic Energy Commission, E-12/A, Agargaon, Sher-e-Blanga Nagar Dhaka-1207 (Bangladesh); Mat-Sharif, K. A. [Lingkaran Teknokrat Timur, Telekom Research and Development, 63000 Cyberjaya, Selangor Darul Ehsan (Malaysia); Amin, Y. M. [University of Malaya, Faculty of Science, Depatment of Physics, 50603 Kuala Lumpur (Malaysia); Bradley, D. A., E-mail: go2munmun@yahoo.com [University of Surrey, Department of Physics, Guildford GU2 7XH (United Kingdom)

    2014-08-15

    Important thermoluminescence (Tl) properties of five (5) different core sizes Ge doped optical fibers have been studied to develop new Tl material with better response. These are drawn from same preform applying different speed and tension during drawing phase. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (Sem) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in SSDL (Secondary Standard Dosimetry Lab) was used for irradiation covering dose range from 1 Gy to 10 Gy. The essential dosimetric parameters that have been studied are Tl linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5 cm length are annealed at temperature of 400 grades C for 1 hour period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1 hour at 400 grades C and subsequently 2 hours at 100 grades C to yield the highest sensitivity. Tl responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100 μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20 μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Z{sub eff}) is found in the range (13.25 to 13.69) that is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. Tl properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation dosimetry. (author)

  9. Thermoluminescence characteristics of different dimensions of Ge-doped optical fibers in radiation dosimetry

    International Nuclear Information System (INIS)

    Begum, M.; Mizanur R, A. K. M.; Abdul R, H. A.; Yusoff, Z.; Begum, M.; Mat-Sharif, K. A.; Amin, Y. M.; Bradley, D. A.

    2014-08-01

    Important thermoluminescence (Tl) properties of five (5) different core sizes Ge doped optical fibers have been studied to develop new Tl material with better response. These are drawn from same preform applying different speed and tension during drawing phase. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (Sem) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in SSDL (Secondary Standard Dosimetry Lab) was used for irradiation covering dose range from 1 Gy to 10 Gy. The essential dosimetric parameters that have been studied are Tl linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5 cm length are annealed at temperature of 400 grades C for 1 hour period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1 hour at 400 grades C and subsequently 2 hours at 100 grades C to yield the highest sensitivity. Tl responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100 μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20 μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Z eff ) is found in the range (13.25 to 13.69) that is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. Tl properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation dosimetry. (author)

  10. Thermoluminescence characteristics of Ge-doped optical fibers with different dimensions for radiation dosimetry

    International Nuclear Information System (INIS)

    Begum, Mahfuza; Rahman, A.K.M. Mizanur; Abdul-Rashid, H.A.; Yusoff, Z.; Begum, Mahbuba; Mat-Sharif, K.A.; Amin, Y.M.; Bradley, D.A.

    2015-01-01

    Important thermoluminescence (TL) properties of five (5) different core sizes Ge-doped optical fibers have been studied to develop new TL material with better response. These are drawn from same preform applying different speed and tension during drawing phase to produce Ge-doped optical fibers with five (5) different core sizes. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge-doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (SEM) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in Secondary Standard Dosimetry Lab (SSDL) was used for irradiation covering dose range from 1 Gy to 10 Gy. The essential dosimetric parameters that have been studied are TL linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5 cm length are annealed at temperature of 400 °C for 1 h period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1 h at 400 °C and subsequently 2 h at 100 °C to yield the highest sensitivity. TL responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100 μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20 μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Z eff ) is found in the range (13.25–13.69) which is higher than soft tissue (7.5) however within the range of human-bone (11.6–13.8). All the fibers can also be re-used several times as a detector after annealing. TL properties of the Ge-doped optical fibers indicate promising applications in

  11. Methods for implementation of in vivo dosimetry (entrance dose) using thermoluminescent dosimeters during radiotherapy treatment with photon beam

    International Nuclear Information System (INIS)

    Barsanelli, Cristiane

    2006-01-01

    Selection, calibration procedure to convert TLD signal into absorbed dose and physical characteristics at the thermoluminescent dosimeters, as well as the determination of correction factors and the methodology to determine expected entrance dose, are described in this work. Practical aspects and the utility of entrance dose measures with thermoluminescent dosimeters were investigated, as well as the exactness and the reproducibility of the daily dose release. The entrance dose measures were performed in five patients with diagnosis of breast cancer treated with a 6 MV photon beam. The measured dose and the expected dose values agreed in ± 5%, due to excellent treatment equipment stability, to automatic verification system and the good exactness in the daily treatment adjustment. Good precision can be achieved when the correction factors for each parameter of influence in the dosimeter response are carefully determined and applied to convert the thermoluminescent signal into absorbed dose. The study demonstrates the viability of thermoluminescent dosimeters use for in vivo dosimetry and its utility as part of a quality assurance program in a radiation therapy service. (author)

  12. 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)

  13. Thermoluminescent dosimetry in pediatric patients subjected to TAC cranium multi cutting studies

    International Nuclear Information System (INIS)

    Tabares V, M.J.; Azorin N, J.; Azorin V, J.C.

    2007-01-01

    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 vol is proportional to the dose to organ. In the case of the skull three-dimensional reconstruction tomography the CTDI vol was practically the same one that for simple tomography was practically; however, the doses to organs differed significantly. When comparing the TDI 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 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)

  14. The Australian radiation protection and nuclear safety agency megavoltage photon thermoluminescence dosimetry postal audit service 2007–2010

    International Nuclear Information System (INIS)

    Oliver, C.P.; Butler, D.J.; Webb, D.V.

    2012-01-01

    The Australian radiation protection and nuclear safety agency (ARPANSA) has continuously provided a level 1 mailed thermoluminescence dosimetry audit service for megavoltage photons since 2007. The purpose of the audit is to provide an independent verification of the reference dose output of a radiotherapy linear accelerator in a clinical environment. Photon beam quality measurements can also be made as part of the audit in addition to the output measurements. The results of all audits performed between 2007 and 2010 are presented. The average of all reference beam output measurements calculated as a clinically stated dose divided by an ARPANSA measured dose is 0.9993. The results of all beam quality measurements calculated as a clinically stated quality divided by an ARPANSA measured quality is 1.0087. Since 2011 the provision of all auditing services has been transferred from the Ionizing Radiation Standards section to the Australian Clinical Dosimetry Service (ACDS) which is currently housed within ARPANSA.

  15. Report on a workshop on the application of thermoluminescence dosimetry to large scale individual monitoring, Ispra, 11-13 September 1985

    International Nuclear Information System (INIS)

    Barthe, J.R.; Christensen, P.; Driscoll, C.M.H.; Marshall, T.O.; Harvey, J.R.; Julius, H.W.; Marshall, M.; Oberhoffer, M.

    1987-01-01

    The workshop was held for the benefit of those actually involved in the operation of large scale automatic thermoluminescence dosimetry systems. It was organised around three overall themes subdivided into 13 subject headings: External constraints: User requirements, Quantities and Units, Legal requirements, Testing, Intercomparisons; Dosimetry systems: Materials, Dosemeter design, Reading systems, Annealing procedures, Rogue readings; Management: Distribution and organisation, Reporting and record keeping, Financial aspects. (author)

  16. Eu{sup 2+} doped TiO{sub 2} nano structures synthesized by HYSYCVD for thermoluminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Perez A, J. A. [Universidad de Sonora, Departamento de Fisica, Apdo. Postal 5-088, 83000 Hermosillo, Sonora (Mexico); Leal C, A. L.; Melendrez A, R.; Barboza F, M., E-mail: alanix89@gmail.com [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83000 Hermosillo, Sonora (Mexico)

    2016-10-15

    Titania (TiO{sub 2}) has attracted interest owing his potential applications as dosimetry material given his excellent optical, electrical and thermal properties and the ability to shape his structure make TiO{sub 2} suitable for research and dosimetry applications. In this work, a systematic study to know the magnitude of processing parameters influence on thermoluminescent properties of undoped (TiO{sub 2}) and doped (TiO{sub 2}:Eu{sup 2+}) nano materials obtained by hybrid precursor systems chemical vapor deposition (HYSYCVD) technique is presented. Synthesis of one dimension nano structures of TiO{sub 2}:Eu{sup 2+} was carried out using K{sub 2}TiF{sub 6} and EuCl{sub 2} as dopant at 0.5, 1, 2.5 and 5 wt %. The nano structures samples were irradiated with β-ray in a doses range of 0.083-3000 Gy. All thermoluminescence (Tl) glow curves showed 3 broad Tl peaks around 373, 473 and 573 K, and a dosimetric linear behavior from 0.083 to 300 Gy. The Tl has a good reproducibility, with deviations of around 5%, making these TiO{sub 2}:Eu{sup 2+} nano materials suitable for dosimetric applications. (Author)

  17. Retrospective dosimetry assessment using the 380 deg. C thermoluminescence peak of tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Secu, C.E. [National Institute for Materials Physics, PO Box MG-7, 77125 Bucharest-Magurele (Romania); Cherestes, M. [Dozimed Ltd., Dosimetry Laboratory, 77125 Bucharest-Magurele (Romania); Secu, M., E-mail: msecu@infim.ro [National Institute for Materials Physics, PO Box MG-7, 77125 Bucharest-Magurele (Romania); Cherestes, C.; Paraschiva, V. [Dozimed Ltd., Dosimetry Laboratory, 77125 Bucharest-Magurele (Romania); Barca, C. [Faculty of Physics, University of Bucharest, 77125 Bucharest-Magurele (Romania)

    2011-10-15

    The thermoluminescence (TL) response to gamma-ray irradiation of tooth enamel is reported. The tooth enamel was separated from dentine by using mechanical and physico-chemical procedures followed by grinding (grain size {approx}100 {mu}m) and etching. The TL was attributed to the recombination of CO{sub 2}{sup -} radicals incorporated into or attached to the surface of hydroxyapatite crystals. The growth of the {approx}380 deg. C TL peak with absorbed dose was examined with irradiated tooth enamel samples and reconstructed doses evaluated for tooth enamel samples from four human subjects. - Highlights: > Thermoluminescence response after gamma-ray irradiation of tooth enamel was investigated. > Thermoluminescence was attributed to the recombination of CO{sub 2}{sup -} radicals. > CO{sub 2}{sup -} radicals are produced inside or at the surface of hydroxyapatite crystals. > From the growth of the 380C peak reconstructed doses have been evaluated.

  18. Thermoluminescent properties of CVD diamond: applications to ionising radiation dosimetry; Proprietes thermoluminescentes du diamant CVD: applications a la dosimetrie des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Petitfils, A

    2007-09-15

    Remarkable properties of synthetic diamond (human soft tissue equivalence, chemical stability, non-toxicity) make this material suitable for medical application as thermoluminescent dosimeter (TLD). This work highlights the interest of this material as radiotherapy TLD. In the first stage of this work, we looked after thermoluminescent (TL) and dosimetric properties of polycrystalline diamond made by Chemically Vapor Deposited (CVD) synthesis. Dosimetric characteristics are satisfactory as TLD for medical application. Luminescence thermal quenching on diamond has been investigated. This phenomenon leads to a decrease of dosimetric TL peak sensitivity when the heating rate increases. The second part of this work analyses the use of synthetic diamond as TLD in radiotherapy. Dose profiles, depth dose distributions and the cartography of an electron beam obtained with our samples are in very good agreement with results from an ionisation chamber. It is clearly shown that CVD) diamond is of interest to check beams of treatment accelerators. The use of these samples in a control of treatment with Intensity Modulated Radiation Therapy underlines good response of synthetic diamond in high dose gradient areas. These results indicate that CVD diamond is a promising material for radiotherapy dosimetry. (author)

  19. Photon and fast neutron dosimetry using aluminium oxide thermoluminescence dosemeters in a pool-type research reactor

    International Nuclear Information System (INIS)

    Santos, J.P.; Marques, J.G.; Fernandes, A.C.; Osvay, M.

    2007-01-01

    Al 2 O 3 :Mg,Y thermoluminescence (TL) dosemeters were used to measure photon and fast neutron doses in the mixed radiation field of the Portuguese Research Reactor. The dosemeters were irradiated in core positions under a photon dose rate of the order of 10 4 Gy/h and a fast neutron flux in the range of 10 9 -10 11 n/cm 2 /s. In order to evaluate the ability of the TL dosemeters for mixed field dosimetry at the research reactor, the measurements were compared with results obtained via conventional methods. The agreement between the different methods is better than 13% for the determination of photon doses and within 5% for the determination of neutron fluxes in mixed fields

  20. Fast neutron dosimetry using CaSO4:Dy thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Azorin, N.G.; Salvi, C.R.; Rubio, J.L.; Gutierrez, C.A.

    1980-01-01

    The use of CaSO 4 :Dy phosphor powder in fast neutron dose measurements using the activation of sulphur from the 32 S(n,p) 32 P reaction is described. The thermoluminescence induced during the irradiation and that due to the decay of short-lived activation products, is erased by annealing the dosimeters after a post-irradiation time of 3 days. The self-induced thermoluminescence measured at different intervals of post-irradiation time, gives an estimation of the fast neutron dose to which the dosimeters were exposed

  1. Operational comparison of bubble (super heated drop) dosimetry with routine albedo thermoluminescent dosimetry for a selected group of Pu-238 workers at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Romero, L.L.; Hoffman, J.M.; Foltyn, E.M.; Buhl, T.E.

    1999-01-01

    This paper is an operational study that compares the use of albedo thermoluminescent dosimeters with bubble dosimeters to determine whether bubble dosimeters do provide a useful daily ALARA tool that can yield measurements close to the dose-of-record. A group of workers at the Los Alamos National Laboratory (LANL) working on the Radioactive Thermoelectric Generators (RTG) for the NASA Cassini space mission wore both bubble dosimeters and albedo dosimeters over a period from 1993 through 1996. The bubble dosimeters were issued and read on a daily basis and the data were used as an ALARA tool. The personnel albedo dosimeter was processed on monthly basis and used as the dose-of-record. The results of this study indicated that cumulative bubble dosimetry results agreed with whole-body albedo dosimetry results within about 37% on average. However it was observed that there is a significant variability of the results on an individual basis both month-to-month and from one individual to another

  2. Thermoluminescence and radioluminescence properties of tissue equivalent Cu-doped Li2B4O7 for radiation dosimetry

    International Nuclear Information System (INIS)

    Cruz Z, E.; Furetta, C.; Marcazzo, J.; Santiago, M.; Guarneros, C.; Pacio, M.; Palomino, R.

    2015-10-01

    Thermoluminescence (Tl) and radioluminescence (Rl) properties of lithium tetraborate (Li 2 B 4 O 7 ) doped with different concentration of copper (0.25, 0.5, 1 wt %) under gamma and beta irradiation has been investigated. The feasibility of using this borate in radiation dosimetry at low doses has been evaluated. Tissue equivalent Li 2 B 4 O 7 was prepared by solid state reaction using mixing stoichiometric compositions of lithium carbonate (Li 2 CO 3 ) and boric acid (H 3 BO 3 ) and a solution of CuCl 2 as dopant. The glow curve, of the most efficient copper doped borate (Li 2 B 4 O 7 :Cu 0.5 wt %), shows a main stable peak centered at 225 degrees C and a second low temperature peak centered at 80 degrees C. The low temperature peak disappears completely after 24 hours of storage in darkness and at room temperature or after an annealing at 120 degrees C for 10 seconds. The main peak of the Li 2 B 4 O 7 :Cu remains constant. The Tl response of Li 2 B 4 O 7 :Cu shows good linearity in the analyzed dose range. The stability and repeatability of Rl signals of the borate have been studied and the Li 2 B 4 O 7 :Cu (0.5 wt %) shown the higher Rl emission and a stable and repetitive response. Results show that Li 2 B 4 O 7 :Cu has prospects to be used in gamma and beta radiation dosimetry. (Author)

  3. In-vivo dosimetry in radiotherapy: a comparison of the response of semiconductor and thermoluminescence (TLD700) dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Vynckier, S [Universite Catholique de Louvain, Brussels (Belgium). Cliniques Universitaires St. Luc; Greffe, J L; Loncol, T; Vanneste, F; Octave-Prignot, M; Denis, J M; De Patoul, N

    1995-12-01

    Semiconductor dosemeters and thermoluminescence dosemeters were calibrated in view of in-vivo dosimetry. Their response in a 8 MV photon beam and the respective correction factors for the treatment conditions were systematically studied. A total of 249 entrance and exit measurements with this dual detector combination were performed, mainly for treatments of the head and neck region. The resulting entrance and exit doses were compared with the expected doses at these positions, calculated on basis of the treatment and patient parameters. The results at the entrance showed a value of 1.010 (2.8% for the ratio of the measured to the calculated dose by diodes, 1.013) 4.9% for the ratio of the measured to the calculated dose by TLD and 1.003 (3.6% for the ratio of the measured dose by TLD to diodes. With respect the exit dose, the results were 0.998) 4.9%, 1.016 (7.7% and 1.019) 7.0% respectively after correction for the heterogeneity`s. Although the standard deviation for the TLD dosemeters is systematically larger than the standard deviation for the diodes, it is concluded that both dosemeters will yield similar results for-in-vivo dosimetry, if utilized under the same conditions.

  4. The determination of the thermal neutron and gamma fluxes at the Maryland University Training Reactor using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Karceski, Jeffrey David; Ebert, David D.; Munno, Frank J.

    1988-01-01

    Determination of the dose received by a material in a mixed gamma and neutron field is of paramount concern to any research reactor owner. This dose can be separated into three distinguishable parts using standard thermoluminescent dosimetry (TLD) responses: 1) thermal neutron dose, 2) fission gamma dose, and 3) fission product gamma dose. For the Maryland University Training Reactor (MUTR), these respective fluences were determined for each of the associated experimental facilities. Quantifying the magnitude of the gamma and thermal neutron exposures at various reactor power levels was accomplished using Li-6F and Li-7F TLDs, respectively. These two types of dosimetry were chosen given the following considerations: 1) there is no existing standard established for fluence determination in a mixed field, 2) the LiF TLDs have a wide range of sensitivity to radiation, from 0.01 mR to 10,000 R, and 3) LiF TLDs are easy to read given the proper equipment. Standardization of the gamma/neutron doses was accomplished using the 500,000 Rad/hr Co-60 gamma source also located at the University of Maryland. (author)

  5. 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)

  6. High dose thermoluminescence dosimetry performance of Sol-gel synthesized TiO{sub 2} phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Salas J, Ch. J.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Castillo U, D. M.; Flores M, K. [Universidad de Sonora, Departamento de Ciencias Quimico Biologicas, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R. [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico); Castano, V. M., E-mail: castillouzeta@gmail.com [UNAM, Instituto de Fisica, Centro de Fisica Aplicada y Tecnologia Avanzada, Apdo. Postal 1-1010, Queretaro, Qro. (Mexico)

    2015-10-15

    Full text: TiO{sub 2} is a ceramic material with many applications due to their different crystalline phases (rutile, anatase and brookite). It has attracted attention in several fields because their high mechanical strength, chemical stability and ion-conducting properties. Moreover, in recent years, some research groups gained interest in the thermoluminescence features of TiO{sub 2} concerning their potential use as thermoluminescence dosimeter. In this work, we present experimental results obtained in the first stage of a long-term research project focused in the synthesis of TiO{sub 2} phosphors for dosimetric applications. The thermoluminescent characterization of samples was carried out after being exposed to beta particle irradiation. TiO{sub 2} was prepared by alkoxide sol-gel route using titanium tetrabutoxide as precursor, ethanol, water and ammonia as catalyst. Pellet-shaped samples were annealed at 700 degrees C for 6 h in air atmosphere followed by slow cooling, and then were exposed to radiation doses from 25 to 400 Gy. The glow curves display maxima located at 103 and 238 degrees C when a 5 C/s heating rate is used. From the experimental results here presented, we conclude that TiO{sub 2} is a promising material to develop high dose Tl dosimeters. (Author)

  7. Thermoluminescent dosimetry of beta radiations of 90 Sr/ 90 Y using ZrO2: Eu

    International Nuclear Information System (INIS)

    Olvera T, L.; Azorin N, J.; Barrera S, M.; Soto E, A.M.; Rivera M, T.

    2005-01-01

    In this work the results of studying the thermoluminescent properties (TL) of the doped zirconium oxide with europium (ZrO 2 : Eu 3+ ) before beta radiations of 90 Sr/ 90 Y are presented. The powders of ZrO 2 : Eu 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 2 : Eu 3+ , previously irradiated with beta particles of 90 Sr/ 90 Y, presented a thermoluminescent curve with two peaks at 204 and 292 C respectively. The TL response of the ZrO 2 : Eu 3+ as function of the absorbed dose was lineal from 2 Gy up to 90 Gy. The fading of the information of the ZrO 2 : Eu 3+ was of 10% the first 2 hours remaining almost constant the information by the following 30 days. The ZrO 2 doped with the (Eu 3+ ) ion it was found more sensitive to the beta radiation that the one of zirconium oxide without doping (ZrO 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)

  8. Thermoluminescent dosimetry of beta radiations of 90 Sr/ 90 Y using amorphous ZrO2

    International Nuclear Information System (INIS)

    Rivera M, T.; Olvera T, L.; Azorin N, J.; Barrera R, M.; Soto E, A.M.

    2005-01-01

    In this work the results of studying the thermoluminescent properties (Tl) of the zirconium oxide in its amorphous state (ZrO 2 -a) before beta radiations of 90 Sr/ 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 3 and Zr-O 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 2 -a, previously irradiated with beta particles of 90 Sr/ 90 Y, presented a thermoluminescent curve with two peaks at 150 and 257 C. The dissipation of the information of the one ZrO 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)

  9. Thermoluminescent dosemeters characterization for patient dosimetry in diagnostic radiology preliminary results;Caracterizacao de dosimetros termoluminescentes para dosimetria de pacientes em radiodiagnostico - resultados iniciais

    Energy Technology Data Exchange (ETDEWEB)

    Castro, William J.; Squair, Peterson L. [Faculdade Novo Rumo, Belo Horizonte, MG (Brazil); Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Gonzaga, Natalia B. [Universidade Unincor, Belo Horizonte, MG (Brazil); Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Nogueira, Maria S.; Silva, Teogenes A. da [Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2009-07-01

    The determination of the metrological characteristics of thermoluminescent (TL) dosimeters plays an important role in dosimetry of patients submitted to x-ray examinations for diagnostic purpose. Entrance surface doses can be measured with TL dosimeters to verify the compliance with the diagnostic reference levels. Organ doses can be estimated through TL measurements in an anthropomorphic phantom which it allows the radiation risk assessment. In this work, LiF:Mg,Ti (TLD-100) rod and chip thermoluminescent dosimeters were characterized considering their use for patient dosimetry in computerized tomography and mammography. Preliminary results showed that TL dosimeters have a response reproducibility of 7.8% and 4.8% and homogeneity of 18.4% and 6.5% for rod and chip shapes, respectively. (author)

  10. Characterization of the thermoluminescent detectors LiF:Mg,Cu,P. Environmental dosimetry applications

    International Nuclear Information System (INIS)

    Ciocci Brazzano, Ligia; Gregori, Beatriz N.; Papadopulos, Susana B.; Carelli, Jorge L.

    2005-01-01

    Studies on thermal-luminescent properties of the LiF:Mg detectors, Cu, P enrichment with Li-7 (99.93% of Li-7 and 0.07% of Li-6): optimization of the heating profile, loss of information, detection limit and doses and energy responses are presented in this work. Their performance is compared with LiF:Mg detectors, Mg, Ti enriched with Li-7 (99.93% of Li-7 and 0.07% Li-6), which are at present used for environmental dosimetry at the Physics Dosimetry Laboratory of the Nuclear Regulatory Authority [es

  11. In vivo dosimetry thermoluminescence dosimeters during brachytherapy with a 370 GBq 192Ir source

    International Nuclear Information System (INIS)

    Cuepers, S.; Piessens, M.; Verbeke, L.; Roelstraete, A.

    1995-01-01

    When using LiF thermoluminescence dosimeters in brachytherapy, we have to take into account the properties of a high dose rate 192 Ir source (energy spectrum ranging form 9 to 885 keV, steep dose gradient in the vicinity of the source) and these of the dosimeters themselves (supralinearity, reproducibility, size). All these characteristics combine into a set of correction factors which have been determined during in phantom measurements. These results have then been used to measure the dose delivered to organs at risk (e.g. rectum, bladder, etc.) during high dose rate brachytherapy with a 370 GBq 192 Ir source for patients with gynaecological tumors

  12. Thermoluminescence of films of metal oxides and its application to the low energy ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Azorin N, J.; Rivera M, T.; Furetta, C.; Falcony G, C.; Martinez S, E.; Garcia H, M.

    2002-01-01

    The obtained results from 1997 to date in the project S tudy of the thermoluminescence of metal oxides and their application to the ionizing radiation as regards to the development of ZrO 2 and of Al 2 O 3 doped and without doped films with rare earths are presented. The obtained results irradiating ZrO 2 and of Al 2 O 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)

  13. In vivo dosimetry thermoluminescence dosimeters during brachytherapy with a 370 GBq {sup 192}Ir source

    Energy Technology Data Exchange (ETDEWEB)

    Cuepers, S; Piessens, M; Verbeke, L; Roelstraete, A [Onze-Lieve-Vrouw Hospitaal, Aalst (Belgium). Dept. of Radiotherapy and Oncology

    1995-12-01

    When using LiF thermoluminescence dosimeters in brachytherapy, we have to take into account the properties of a high dose rate {sup 192}Ir source (energy spectrum ranging form 9 to 885 keV, steep dose gradient in the vicinity of the source) and these of the dosimeters themselves (supralinearity, reproducibility, size). All these characteristics combine into a set of correction factors which have been determined during in phantom measurements. These results have then been used to measure the dose delivered to organs at risk (e.g. rectum, bladder, etc.) during high dose rate brachytherapy with a 370 GBq {sup 192}Ir source for patients with gynaecological tumors.

  14. Absorbed dose from a beta source as shown by thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Wintle, A.G.; Aitken, M.J.

    1977-01-01

    The depth-dose curve was obtained for a 90 Sr- 90 Y beta source using a fine grain TL phosphor to measure the observed dose, aluminium absorbers being interposed between the source and the detector; the curve went through a maximum at an absorber thickness of about 40 mg cm -2 . This curve was then used to predict the average dose rate to various thicknesses of calcium fluoride which has a similar absorption characteristic to aluminium; these values were compared with experimentally determined dose rates. This work was done in connection with thermoluminescence dating of flint and calcite in archaeology and geology. (author)

  15. Clinical use of LiF:Mg,Cu,P: Critical evaluation of an ultrasensitive material for thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Duggan, Lisa

    2002-01-01

    Radiation dosimetry is an essential part of optimization in medical exposures. However there are medical procedures that are particularly challenging for existing dosimetric techniques: neonatal radiography (low dose), mammography (low energy), cardiac catheterization (moving radiation fields), and brachytherapy using implanted radionuclides (steep dose gradients). Hence, the objectives of this thesis were to study the dosimetric characteristics of ultrasensitive LiF:Mg,Cu,P thermoluminescence dosimeters (TLDs) in radiation beams typical for both diagnostics and therapy, and develop procedures to implement this dosimeter into clinical practice for those selected scenarios. GR-200 (SDDML, China) and MCP-N (TLD Poland) TLDs were compared to other TLD materials (LiF:Mg,Ti, Al 2 O 3 :C) and tested for reproducibility, dose response (1 μGy to 500 Gy), photon energy response (10 keV to 18 MVp), light sensitivity (240-800 nm), long-term stability (6 months) using different annealing cycles and glow curve deconvolution. A miniaturized TLD form (MCP-Np) was developed by TLD Poland for the present investigations. Detection limit of GR-200 and MCP-Np was found to be less than 1 and 8 μGy, respectively, with dose response linear up to 18 Gy. To obtain adequate detection limits and precision, accurate temperature calibration of heating cycles and a dual-anneal technique with dose history monitoring was performed. Energy response was similar for both materials within 5% and essentially uniform except for a minimum of 0.82 at 185 keV. LiF:Mg,Cu,P proved to be more suitable than LiF:Mg,Ti for dosimetry in low dose medical applications particularly when kilovoltage photons are to be used. The high sensitivity and resulting scope for miniaturization provided the opportunity to perform unique in vivo measurements within brachytherapy implants and for mammography

  16. Comparative measurements on different thermoluminescence materials for the dosimetry in mixed radiation fields; Vergleichende Messungen an unterschiedlichen Thermolumineszenzmaterialien fuer die Dosimetrie in gemischten Strahlenfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Pillath, J.; Uray, I.

    2006-05-15

    LiF-based thermoluminescence materials (TL materials) have proved efficient and become established for dosimetry for many years now. In combination with suitable filtrations or moderators, they permit high-precision measurements of the radiation doses of all types of radiation relevant in radiation protection. The development of highly sensitive LiF materials with a doping of Mg, P and Cu has made it possible to measure doses down to one {mu}Sv. The measurements presented here specifically serve to phenomenologically analyse the glow curve structure of normally and highly sensitive LiF-TL materials in mixed gamma-neutron radiation fields. The sensitivity of the different TL materials to different types of radiation and the influence of the radiation types and of the evaluation parameters on the structure of the glow curves is examined. It is made apparent how information about the composition and doses of the individual components of a radiation field can be obtained by decomposing the glow curve into its individual peaks. (orig.)

  17. The quality control program for an Ontario Hydro operated thermoluminescence dosimetry service at nuclear generating stations

    International Nuclear Information System (INIS)

    Orr, B.H.; Walsh, M.L.

    1975-11-01

    An essential aspect of the Ontario Hydro TLD service is the operation of an acceptable quality control (QC) program. The QC program which has been generally accepted by the A.E.C.B. is presented in this document. The aims of the program are as follows: (1) to ensure that Ontario Hydro maintains an acceptable standard of dosimetry; (2) to be able to demonstrate to any interested party that the dose measurements for individual workers have a high degree of credibility. (author)

  18. Statistical differences and systematic effect on measurement procedure in thermoluminescent dosimetry of the Iodine-125 brachytherapy seed

    International Nuclear Information System (INIS)

    Zeituni, Carlos A.; Moura, Eduardo S.; Rostelato, Maria Elisa C.M.; Manzoli, Jose E.; Moura, Joao Augusto; Feher, Anselmo; Karam, Dib

    2009-01-01

    In order to provide the dosimetry for Iodine-125 seed production in Brazil, Harshaw thermoluminescent dosimeters (TLD-100) will be used. Even if measurements with TLD-100 of the same batch of fabrication are performed, the response will not be the same. As a consequence, they must be measured one by one. These dosimeters are LiF type with a micro-cube (1 mm x 1 mm x 1 mm) shape. Irradiations were performed using Iodine-125 seeds to guarantee the same absorbed dose of 5 Gy in each dosimeter. It has been used a Solid Water Phantom with three concentrically circle with 20 mm, 50 mm and 70 mm diameters. The angle of positions used was 0 deg, 30 deg, 60 deg and 90 deg. Of course there are 2 positions in 0 deg and 90 deg and 4 positions in 30 deg and 60 deg. These complete procedures were carried out five times in order to compare the data and minimize the systematic error. The iodine-125 seed used in the experiment was take off in each measure and put again turning his position 180 deg to guarantee the systematic error was minimized. This paper presents also a little discussion about the statistical difference in the measurement and the calculation procedure to determine the systematic error in these measurements. (author)

  19. Synthesis, characteristics and thermoluminescent dosimetry features of γ-irradiated Ce doped CaF2 nanophosphor.

    Science.gov (United States)

    Zahedifar, M; Sadeghi, E; Mozdianfard, M R; Habibi, E

    2013-08-01

    Nanoparticles of cerium doped calcium fluoride (CaF2:Ce) were synthesized for the first time using the hydrothermal method. The formation of nanostructures was confirmed by X-ray diffraction (XRD) patterns, indicating cubic lattice structure for the particles produced. Their shape and size were observed by scanning electron microscopy (SEM). Thermoluminescence characteristics were studied by having the samples irradiated by gamma rays of (60)Co source. The optimum thermal treatment of 400 °C for 30 min was found for the produced nanoparticles. The Tm-Tstop and computerized glow curve deconvolution (CGCD) methods, used to determine the number of component glow peaks and kinetic parameters, indicated seven overlapping glow peaks on the TL glow curve at approximately 394, 411, 425, 445, 556, 594 and 632 K. A linear dose response of up to 2000 Gy, was observed for the prepared nanoparticles. Maximum TL sensitivity was found at 0.4 mol% of Ce impurity. Other TL dosimetry features, including reusability and fading, were also presented and discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. An extended role for thermoluminescent phosphors in personnel, environmental and accident dosimetry using sensitisation, re-estimation and fast fading

    International Nuclear Information System (INIS)

    Charles, M.W.

    1983-01-01

    This paper summarises some techniques for extending the usefulness of conventional phosphors in personnel, environmental and accident dosimetry. An optimised procedure for utilising radiation sensitisation and UV re-estimation in thermoluminescent LiF is presented. In particular it is shown that optimum performance is achieved by using a UV wavelength of 250 +- 10 nm for both the UV/thermal anneal following sensitisation, and for the UV re-estimation procedure. In the case of Harshaw Lif Chips (3x3x0.9 mm 3 ) the sensitivity is increased by a factor of 4-5 to achieve a minimum detectable dose of approx.=10 μGy (2sigma) and a minimum re-estimable dose of 50-100 mGy (2sigma), dependent on batch. Sensitized LiF also exhibits improved tissue equivalence, extended linearity and improved precision at low doses. The information from fast-fading glow peaks, which is normally rejected, is shown to have a useful application to the evaluation of short-term increases in environmental dose rates such as may occur following accidental releases of radioactivity. (orig.)

  1. Statistical differences and systematic effect on measurement procedure in thermoluminescent dosimetry of the Iodine-125 brachytherapy seed

    Energy Technology Data Exchange (ETDEWEB)

    Zeituni, Carlos A.; Moura, Eduardo S.; Rostelato, Maria Elisa C.M.; Manzoli, Jose E.; Moura, Joao Augusto; Feher, Anselmo, E-mail: czeituni@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil); Karam, Dib [Universidade de Sao Paulo (USP Leste), Sao Paulo, SP (Brazil). Escola de Artes, Ciencias e Humanidades

    2009-07-01

    In order to provide the dosimetry for Iodine-125 seed production in Brazil, Harshaw thermoluminescent dosimeters (TLD-100) will be used. Even if measurements with TLD-100 of the same batch of fabrication are performed, the response will not be the same. As a consequence, they must be measured one by one. These dosimeters are LiF type with a micro-cube (1 mm x 1 mm x 1 mm) shape. Irradiations were performed using Iodine-125 seeds to guarantee the same absorbed dose of 5 Gy in each dosimeter. It has been used a Solid Water Phantom with three concentrically circle with 20 mm, 50 mm and 70 mm diameters. The angle of positions used was 0 deg, 30 deg, 60 deg and 90 deg. Of course there are 2 positions in 0 deg and 90 deg and 4 positions in 30 deg and 60 deg. These complete procedures were carried out five times in order to compare the data and minimize the systematic error. The iodine-125 seed used in the experiment was take off in each measure and put again turning his position 180 deg to guarantee the systematic error was minimized. This paper presents also a little discussion about the statistical difference in the measurement and the calculation procedure to determine the systematic error in these measurements. (author)

  2. Thermoluminescence properties of home-made CaSO4:Dy For Dosimetry Purposes

    International Nuclear Information System (INIS)

    Kamal, S.M.; Gerges, A.S.; Al-Said, M.A.

    2004-01-01

    Dysprosium doped Calcium Sulfate (CaSO 4 :Dy) had been first prepared by Yamashita in 1968 with method based on acid evaporation in an open system, which pose human health risks, corrosion and pollution to the environment due to sulfuric acid vapor. It has found increasing use in various applications in the field of radiation dosimetry due to their ease of preparation as compared to many other sensitive TL materials. Many researchers emphasized that the grain size and impurities influence the relative intensities of the broad glow peaks as well as overall sensitivities. In this paper, we introduce a new method of preparation for avoiding all of these disadvantages and improving the main TL materials properties, which required for dosimetric use. The main TL characteristics of home-made CaSO 4 :Dy .crystals with different concentrations are investigated alter the preparation and heat treatment conditions. The results indicated a linear response from 5μ .Gy up to 10 Gy with the highest sensitivity obtained at 0.25 mol % and optimum sensitivity at less than 75 jam grain sizes. Three peaks at 137 degree C, 222 degree C and 311 degree C were obtained. We conclude to use our home-made prepared CaSO 4 :Dy with 0.25 mol % concentration for gamma-ray dosimetry as more sensitive and cheaper than commercial phosphor (TLD-900). This will increase the routine and research work in the area of TL dosimetry

  3. Thermoluminescent dosimetry of UV light using ZrO2:Gd films

    International Nuclear Information System (INIS)

    Flores D, R.C.; Rivera M, T.; Azorin N, J.; Falcony G, C.; Garcia H, M.; Martinez S, E.

    2002-01-01

    The samples used for the study are films of zirconium oxide activated with gadolinium (ZrO 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 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)

  4. Thermoluminescent dosimetry applied to radiotherapy carried out around the Therac-20-Saturne linear accelerator

    International Nuclear Information System (INIS)

    Bennab, K.

    1984-10-01

    In the first part of this work, the physical and technical aspects necessary to a radiotherapy treatment planning elaboration are presented. These include the apparatus description as well as the measurements of the dosimetric quantities relative to the delivered beams. Since in-vivo measurements are very useful to optimise the treatment conditions, the second part deals with thermoluminescent dosimeters, their characteristics and their setting out such as they be used with maximum efficiency. In-vivo measurements carried out enabled us to estimate the delivered dose to a given tumor with a precision down to +-4%. The registered differences between the measured dose and the prescribed one made possible an appropriate corrective action. Because of the difficulties encountered with conventional dosimetric systems when used in narrow beam measurements, we have developed a new method making use of TL dosimeters. The results obtained will allow treatments of small volume tumors with the significant advantage of saving healthy surrounding tissues from irradiation

  5. Thermoluminescence dosimetry properties of new Cu doped CaF(2) nanoparticles.

    Science.gov (United States)

    Zahedifar, M; Sadeghi, E

    2013-12-01

    Nanoparticles of Cu-doped calcium fluoride were synthesised by using the hydrothermal method. The structure of the prepared nanomaterial was characterised by the X-ray diffraction (XRD) pattern and energy dispersive spectrometer. The particle size of 36 nm was calculated from the XRD data. Its shape and size were also observed by scanning electron microscope. Thermoluminescence (TL) and photoluminescence of the produced phosphor were also considered. The computerised glow curve deconvolution procedure was used to identify the number of glow peaks included in the TL glow curve of the CaF2:Cu nanoparticles. The TL glow curve contains two overlapping glow peaks at ∼413 and 451 K. The TL response of this phosphor was studied for different Cu concentrations and the maximum sensitivity was found at 1 mol% of Cu impurity. Other dosimetric characteristics of the synthesised nanophosphor are also presented and discussed.

  6. Characterization of nanoporous Al{sub 2}O{sub 3}:C for thermoluminescent radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Barros, V.S.M. de [Departamento de Energia Nuclear-UFPE, Rua prof Luiz Freire, 1000, Recife, PE 50740-540 (Brazil)], E-mail: vdbarros@terra.com.br; Khoury, H.J. [Departamento de Energia Nuclear-UFPE, Rua prof Luiz Freire, 1000, Recife, PE 50740-540 (Brazil); Azevedo, W.M. [Departamento de Quimica Fundamental-CCEN Recife, PE 50740-540 (Brazil); Silva, E.F. da [Departamento de Fisica CCEN Recife, PE 50740-540 (Brazil)

    2007-09-21

    Thermoluminescent (TL) {alpha}-Al{sub 2}O{sub 3}:C dosimeters, produced in the form of single crystals, show a high sensitivity to ionizing radiation (about 40-60 times higher than LiF:Mg,Ti). However, the crystal growth requires high temperatures (2050 deg. C) and highly reducing atmospheres. This paper presents the TL response of thin nanoporous Al{sub 2}O{sub 3}:C membranes obtained by electrochemical anodizing of aluminum in organic acid solutions at room temperature. The TL properties of the samples were analyzed as a function of the anodizing voltage in the interval 30-60 V and of the acid concentrations from 0.05 to 0.6 M. The dosimetric response of the samples for {sup 60}Co gamma radiation is linear with dose, and the best response was found for samples anodized at 130 V with 0.10 M acid concentration.

  7. 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)

  8. 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)

  9. Determination, through of thermoluminescence dosimetry, of the incident radiation in critical organs, during cephalometric radiographies

    International Nuclear Information System (INIS)

    Hipolito Junior, O. di; Goncalves, N.; Boscolo, F.N.; Montebelo Filho, A.

    1985-01-01

    The object of this paper was to value and to compare the doses of X-ray incident in critical orgas of patient and operator, during cephalometric radiography. Each patient was submited for two radiographics expositions. First of all, they use the followings factors: 85 kVp, 15 mA and 4/10 s of exposition; while of the second radiography the conditions were of 70 kVp, 15 mA and 1.2 s of exposition. The dosimetric method was the thermoluminescent through the LiF-700. Although the cephalometric radiographies showed similars qualities, in bot conditions where the equipment functioned, the situation of high voltage was noted small doses of radiation. (author) [pt

  10. Synthesis of CaF{sub 2}: dy for thermoluminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Yamato, M.E.P.; Vasconcelos, D.A.A. de; Asfora, V.K.; Khoury, H.J.; Santos, R.A.; Barros, V.S.M., E-mail: mepyamato@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear

    2015-07-01

    Calcium Fluoride doped with dysprosium is a known thermoluminescent material for applications that require highly sensitive dosimeters. Research in novel methods such as Combustion Synthesis (CS) has been ongoing for several years at the University of Pernambuco. The method uses the heat of the oxi-redox reaction a between nitrate and a fuel. This work presents results of CaF{sub 2}:Dy produced by combustion synthesis under different fabrication conditions. Samples were prepared by mixing stoichiometric amounts of calcium nitrate, urea and ammonium nitrate in a beaker under vigorous stirring. The resulting gel was transferred to a pre-heated muffle furnace were the combustion reaction occurred after a few minutes. For comparison, a variation of the production method with the same amounts of nitrate, ammonium fluoride and dopant, but without using the fuel was prepared. For both methods the resulting powder was pelleted and irradiated with Co-60 gamma radiation. The reproducibility and sensitivity for gamma dose irradiation was tested and results showed that optimum TL sample reproducibility was without the urea as fuel. Samples were then prepared with 0.05, 0.10, 0.15 and 0.20 mol% Dy concentration. The highest TL sensitivity was found for samples with 0.15 mol% Dy and sintered at 400 deg C for 3.5 h in air. The TL emission spectra, obtained using a Hammamatsu optical spectrometer, was comparable with commercial CaF{sub 2}:Dy. Thermoluminescence was measured in a Harshaw-Bicron 3500 TL Reader. The glow curve showed stable dosimetric peaks at around 200, 235 and 300 deg C were a linear dose response curve was obtained for the range 100 mGy to 1000 mGy. (author)

  11. Selected references on thermoluminescent dosemeters for personnel monitoring

    International Nuclear Information System (INIS)

    Lawson, Helen

    1976-08-01

    This bibliography contains references on: specific thermoluminescent dosemeters used for personnel dosimetry; comparisons of thermoluminescent and other dosemeters for personnel monitoring and read-out apparatus for thermoluminescent dosemeters. An appendix contains selected foreign language references. (author)

  12. Assessment of CaSO4:Dy and LiF:Mg,Ti thermoluminescent dosimeters performance in the dosimetry of clinical electron beams

    International Nuclear Information System (INIS)

    Nunes, Maira Goes

    2008-01-01

    The assessment of the performance of CaS0 4 :Dy thermoluminescent detectors produced by IPEN in the dosimetry of clinical electron beams aims to propose an alternative to the LiF:Mg,Ti commercial dosimeters (TLD-100) largely applied in radiation therapy. The two types of thermoluminescent dosimeters were characterised with the use of PMMA, RMI-457 type solid water and water phantoms in radiation fields of 4, 6, 9, 12 and 16 MeV electrons of nominal energies in which the dose-response curves were obtained and the surface and depth doses were determined. The thermoluminescent response dependency with the electron nominal energies and the applied phantom were studied. The CaS0 4 :Dy presented the same behaviour than the LiF:Mg,Ti in such a way that its application as an alternative to the TLD-100 pellets in the radiation therapy dosimetry of electron beams is viable and presents the significantly higher sensitivity to the electron radiation as its main advantage. (author)

  13. An in vivo investigative protocol for HDR prostate brachytherapy using urethral and rectal thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Toye, Warren; Das, Ram; Kron, Tomas; Franich, Rick; Johnston, Peter; Duchesne, Gillian

    2009-01-01

    Purpose: To develop an in vivo dosimetry based investigative action level relevant for a corrective protocol for HDR brachytherapy boost treatment. Methods and materials: The dose delivered to points within the urethra and rectum was measured using TLD in vivo dosimetry in 56 patients. Comparisons between the urethral and rectal measurements and TPS calculations showed differences, which are related to the relative position of the implant and TLD trains, and allowed shifts of implant position relative to the prostate to be estimated. Results and conclusions: Analysis of rectal dose measurements is consistent with implant movement, which was previously only identified with the urethral data. Shift corrected doses were compared with results from the TPS. Comparison of peak doses to the urethra and rectum has been assessed against the proposed corrective protocol to limit overdosing these critical structures. An initial investigative level of 20% difference between measured and TPS peak dose was established, which corresponds to 1/3 of patients which was practical for the caseload. These patients were assessed resulting in corrective action being applied for one patient. Multiple triggering for selective investigative action is outlined. The use of a single in vivo measurement in the first fraction optimizes patient benefit at acceptable cost.

  14. Dosimetry characteristics of thermoluminescent Li2B4O7:Cu phosphor

    International Nuclear Information System (INIS)

    Lakshmanan, A.R.; Chandra, B.; Bhatt, R.C.

    1981-01-01

    Preliminary investigations on the radiation dosimetry characteristics of Li 2 B 4 O 7 :Cu TLD phosphor are described. The major TL peak in this phosphor occurs at 230 0 C and its TL sensitivity to gamma radiation is two to three times higher than that of LiF TLD-100. The gamma dose Vs TL response of this peak is linear (within +- 20%) in the dose range 0.3 mGy-3x10 2 Gy above which saturation sets in. Its TL response for 30 keV X-rays is about 20% lower than that for 60 Coγ-rays. On annealing at 300 0 C, the phosphor gets slightly discoloured (brownish). This results in the reduction of the TL sensitivity by about 20 - 25%. The phosphor does not exhibit either sensitization or damage even after a gamma dose of 10 3 Gy. The TL emission spectrum has a broad peak at 360 nm. The intrinsic TL sensitivity of virgin Li 2 B 4 O 7 :Cu to 253.7 nm UV radiation is nearly 50 times higher than that of CaSO 4 :Dy. The post-irradiation fading in Li 2 B 4 O 7 :Cu at ambient temperature and humidity conditions is, however, less than 10% in 17 days. These characteristics indicate that Li 2 B 4 O 7 :Cu is a promising phosphor for ionizing as well as UV radiation dosimetry. (author)

  15. The dielectric track and thermoluminescent detectors applied to neutron dosimetry in personnel monitoring

    International Nuclear Information System (INIS)

    Mebhah, D.

    1984-03-01

    The personnal dosimeter for neutron based on the detection of fission fragments from 237 Np and 232 Th by a polycarbonate 10 gm, and lithium fluorite 6 LIF/ 7 LIF, allow to cover an energy spectrum from 0.05 eV to 14 MeV with a easy neutron gamma discrimination. In criticality dosimetry, the energy spectrum of the incident neutrons can be defined by two components: the fast component by E b exp(-ae) with E between 0.1 and 14 MeV, a and b determined by a combination of 237 Np and 232 Th track detector responses, and the epithermal component in 1/E, the thermal component having a minor contribution to the total equivalent dose. We took into account the body influence on the detectors response by introducing effective cross section. The equivalent dose obtained by this dosimeter is 20% overestimated in low doses dosimetry. The interpretation of the detectors responses is based on the definition of a factor and a calibration parameter for each zone in which the spectrum is constant. The knowledge of this parameter for individual dosimeters allows to account for the variations of the conditions of calibration

  16. Measurements of radiation exposure of dentistry students during their radiological training using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Loya, M.; Sanín, L.H.; González, P.R.; Ávila, O.; Duarte, R.; Ojeda, S.L.; Montero-Cabrera, M.E.

    2016-01-01

    Exposure among dentistry students has not been assessed or regulated in Mexico. This work assessed the average exposure of 35 dentistry students during their training with the aid of LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters. For the students in the roles of dentist and observers, maximum accumulated equivalent dose obtained was 2.59±0.11 and 4.64±0.39 mSv, respectively. Students in the role as patients received a maximum accumulated effective dose of 28.41±0.31 mSv. If compared to occupational dose limits, this latter value is 56% of the recommended value of 50 mSv in any year. It was found that in all cases, values of equivalent dose to the women breasts were equal to the background dose. Results are discussed and compared to previous published work. Suggested recommendations were given to authorities in order to minimize exposure of the students in the role as patients. - Highlights: • Dose of training dentistry students was estimated with LiF:Mg,Cu,P+PTFE dosimeters. • The average effective dose of students in the role of patient was also estimated. • The sum of organ doses from TL measurements is considered as the whole body dose. • The uncertainty in the results was less than 2%.

  17. Manufacturing polycrystalline pellets of natural quartz for applications in thermoluminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho Junior, Alvaro Barbosa de; Khoury, Helen Jamil [Federal University of Pernambuco (UFPE), Recife, PE (Brazil). Department of Nuclear Energy; Barros, Thiago Fernandes; Guzzo, Pedro Luiz [Federal University of Pernambuco (UFPE), Recife, PE (Brazil). Department of Mining Engineering

    2012-07-15

    This paper describes the manufacturing process of quartz-pellets and shows their potential use as thermoluminescence dosimeters (TLD) for those applications where low-levels of ionising radiation are present. Two batches of cold-pressed pellets were produced and their resistance were evaluated by vibration tests and weight-loss measurements. The batch manufactured with 75 Multiplication-Sign 150 Micro-Sign m particles showed enough resistance to be employed as TLD. The dosimetric properties of the 310 Degree-Sign C peak appearing in the glow curves of these pellets were characterized together with commercial TLD-100 units using {gamma}- and X-ray beams with different energies. The uncertainties related to reproducibility and stability of the TL signal were better than 10%. The sensitivity and the linearity of the TL response of quartz-pellets were better than that measured for TLD-100 for doses ranging from 0.5 to 200mGy. The energy dependence of the quartz-pellets was higher than that of TLD-100 but it cannot be considered a restriction to their use in clinical procedures and industrial applications. (author)

  18. Use of thermoluminescence dosimetry for evaluation of internal beta dose-rate in archaeological dating

    Energy Technology Data Exchange (ETDEWEB)

    Bailiff, I K; Aitken, M J [Oxford Univ. (UK). Research Lab. for Archaeology

    1980-07-01

    An experimental technique is described for the absolute determination of beta dose-rate in pottery. The calibrated system utilizes thermoluminescent dosimeters (natural calcium fluoride) which are located external to the pottery sample. These measurements give an evaluation of the dose-rate at the centre of the pottery that is effectively independent of the relative importance of the thorium, uranium and potassium content (typically 12 ppm Th, 3 ppm U and 1% K/sub 2/O in pottery). This has been checked using analysed uranium, thorium and potassium materials. A dose-rate evaluation may be made after 10-14 d with an accuracy of +-5%, where the dose-rate to the dosimeter is of the order of 0.3 mrad d/sup -1/. Although the background dose-rate due to cosmic radiation and that arising from radioactive impurities in the calcium fluoride is significant (one third), measurements have shown that it may be accurately established. The technique described is to be preferred to other systems used in pottery dating because of its independence of relative radioisotope concentration.

  19. A study into the mechanism of thermoluminescence in a LiF:Mg,Ti dosimetry material

    International Nuclear Information System (INIS)

    Piters, T.M.

    1993-01-01

    Thermoluminescence (TL) is the phenomenon of light emission from an insulator or semiconductor when it is heated after a previous absorption of energy from ionising radiation. The purpose of the research described in this thesis is to get more insight into the mechanism of TL in LiF:Mg, Ti. In chapter 2 the idea of defect reactions during the readout is introduced as a possible explanation for the dependence of the read-out heating rate on TL. In chapter 3 a mode for the description of the emission band is described. The construction of a TL facility comprising the TL emission spectrometer is described in chapter 4. Chapter 5 gives an estimation for the possible errors that are made in the data analysis due to imperfect heat transfer from heater to sample. In chapter 6 results of measurements of TL emission spectra of a LiF:Mg, Ti (TLD-100) sample and three LiF:Mg, Ti samples with different impurity concentrations (0-6 ppm Ti and 80-100 ppm Mg) at different read out, annealing procedure and irradiation dose are described. At dose levels less than 22 Gy the emission spectra of the TLD-100 sample and the sample without Ti comprise one emission band at 420 nm and 620 nm, respectively. The TL emission spectra of the other two samples comprise two emission bands at 420 nm and 620 nm. (orig./MM)

  20. A study into the mechanism of thermoluminescence in a LiF:Mg,Ti dosimetry material

    Energy Technology Data Exchange (ETDEWEB)

    Piters, T M

    1993-10-11

    Thermoluminescence (TL) is the phenomenon of light emission from an insulator or semiconductor when it is heated after a previous absorption of energy from ionising radiation. The purpose of the research described in this thesis is to get more insight into the mechanism of TL in LiF:Mg, Ti. In chapter 2 the idea of defect reactions during the readout is introduced as a possible explanation for the dependence of the read-out heating rate on TL. In chapter 3 a mode for the description of the emission band is described. The construction of a TL facility comprising the TL emission spectrometer is described in chapter 4. Chapter 5 gives an estimation for the possible errors that are made in the data analysis due to imperfect heat transfer from heater to sample. In chapter 6 results of measurements of TL emission spectra of a LiF:Mg, Ti (TLD-100) sample and three LiF:Mg, Ti samples with different impurity concentrations (0-6 ppm Ti and 80-100 ppm Mg) at different read out, annealing procedure and irradiation dose are described. At dose levels less than 22 Gy the emission spectra of the TLD-100 sample and the sample without Ti comprise one emission band at 420 nm and 620 nm, respectively. The TL emission spectra of the other two samples comprise two emission bands at 420 nm and 620 nm. (orig./MM).

  1. Assessment of dose in thyroid and salivary glands in dental radiology using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Mantuano, Natalia de O.; Silva, Ademir X. da; Correa, Samanda C.A.

    2011-01-01

    Radiobiological and epidemiological studies have provided evidence of risk of salivary and thyroid glands tumors incidence associated with oral radiology. Based on these studies, the tissue weighting factors were reviewed by the International Commission on Radiological Protection (ICRP) in 2007. The main objective of the present work is to estimate the absorbed dose on thyroid and salivary glands (parotid, submandibular and sublingual), during a complete periapical examination. The complete periapical examination was simulated using a Spectro 70X Seletronic X-ray dental equipment on an Alderson Rando phantom with Harshaw LiF:Mg,Ti thermoluminescent dosemeters (TLD100). A PTW DIADOS dosimetric system was used for calibration. The TLD100 were inserted into the phantom slices corresponding to the organs of interest. During a complete periapical examination, the highest evaluated mean absorbed dose was 4.9 mGy in the right submandibular gland and the lowest one of 1.5 mGy in the left thyroid lobe. Entrance surface doses ranged from 2.1 to 2.6 mGy, measured, respectively, for the techniques of upper left molar and lower right molar. When compared with the diagnostic reference levels (DRL), the entrance surface doses values were lower than the DRLs recommended in Brazilian current legislation. However, the dosimetric results show the need of optimization for complete periapical examination to minimize patient exposure. Measurements were performed without the use of thyroid protectors. The use of this device is certainly an easy and simple method of dose reduction. (author)

  2. Localized transitions in the thermoluminescence of LiF : Mg,Ti: potential for nanoscale dosimetry

    CERN Document Server

    Horowitz, Y S; Biderman, S; Einav, Y

    2003-01-01

    We describe the effect of nanoscale spatially coupled trapping centre (TC)-luminescent centre (LC) pairs on the thermoluminescence (TL) properties of LiF : Mg,Ti. It is shown that glow peak 5a (a low-temperature satellite of the major glow peak 5) arises from localized electron-hole (e-h) recombination in a TC-LC pair believed to be based on Mg sup 2 sup + -Li sub v sub a sub c trimers (the TCs) coupled to Ti(OH) sub n molecules (the LCs). Due to the localized nature of the e-h pair, two important properties are affected: (i) heavy charged particle (HCP) TL efficiency: the intensity of peak 5a relative to peak 5 following HCP high-ionization density irradiation is greater than that following low ionization density irradiation in a manner somewhat similar to the ionization density dependence of the yield of double-strand breaks (DSBs) induced in DNA. Our experimental measurements in a variety of HCP and fast neutron radiation fields have demonstrated that the ratio of glow peaks 5a/5 is nearly independent of p...

  3. Assessment of dose in thyroid and salivary glands in dental radiology using thermoluminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Mantuano, Natalia de O.; Silva, Ademir X. da [Instituto Alberto Luiz Coimbra de Pos-Graduacao e Pesquisa em Engenharia (PEN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear; Canevaro, Luca V.; Mauricio, Claudia Lucia P. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ) Rio de Janeiro, RJ (Brazil); Correa, Samanda C.A., E-mail: scorrea@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Radiobiological and epidemiological studies have provided evidence of risk of salivary and thyroid glands tumors incidence associated with oral radiology. Based on these studies, the tissue weighting factors were reviewed by the International Commission on Radiological Protection (ICRP) in 2007. The main objective of the present work is to estimate the absorbed dose on thyroid and salivary glands (parotid, submandibular and sublingual), during a complete periapical examination. The complete periapical examination was simulated using a Spectro 70X Seletronic X-ray dental equipment on an Alderson Rando phantom with Harshaw LiF:Mg,Ti thermoluminescent dosemeters (TLD100). A PTW DIADOS dosimetric system was used for calibration. The TLD100 were inserted into the phantom slices corresponding to the organs of interest. During a complete periapical examination, the highest evaluated mean absorbed dose was 4.9 mGy in the right submandibular gland and the lowest one of 1.5 mGy in the left thyroid lobe. Entrance surface doses ranged from 2.1 to 2.6 mGy, measured, respectively, for the techniques of upper left molar and lower right molar. When compared with the diagnostic reference levels (DRL), the entrance surface doses values were lower than the DRLs recommended in Brazilian current legislation. However, the dosimetric results show the need of optimization for complete periapical examination to minimize patient exposure. Measurements were performed without the use of thyroid protectors. The use of this device is certainly an easy and simple method of dose reduction. (author)

  4. Use of the pre-dose technique for environmental dosimetry. [Thermoluminescence from fired bricks or tiles

    Energy Technology Data Exchange (ETDEWEB)

    Bailiff, I K [Durham Univ. (UK). TL Lab.; Haskell, E H [Utah Univ., Salt Lake City (USA). Radiobiology Div.

    1984-01-01

    The pre-dose effect associated with the 110/sup 0/C TL peak of quartz is the basis of a dating technique developed at the Oxford Laboratory, and now in use to date pottery and brick at the Durham Laboratory. Recently its use for the measurement of fallout gamma dose has been initiated at the University of Utah. Using quartz extracted from fired brick, the technique has been shown to be sufficiently sensitive to measure doses in the region of 10 mGy. The complexities of the technique encountered during dating in its upper range (approx. 5 Gy) are equally apparent in its lower range (10 mGy). With a common interest in the pre-dose technique, the research that is being performed to apply the technique through its full range in environmental dosimetry is discussed.

  5. Calculation of the uncertainty of HP (10) evaluation for a thermoluminescent dosimetry system

    International Nuclear Information System (INIS)

    Ferreira, M.S.; Silva, E.R.; Mauricio, C.L.P.

    2016-01-01

    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 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 c (y) and expanded (U) uncertainty. For 10 mSv, it was obtained u c (y) = 1,99 mSv and U = 3,98 mSv for 95% of coverage interval. (author)

  6. UV induced thermoluminescence in rare earth oxide doped phosphors: possible use for UV dosimetry

    International Nuclear Information System (INIS)

    Yeh, S.-M.; Su, C.-S.

    1996-01-01

    UV induced thermoluminescent (TL) phenomena in some phosphors doped with rare earth oxides (Gd 2 O 3 :Eu, Gd 2 O 3 :Tb, Gd 2 O 3 :Dy and Y 2 O 3 :EU) have been investigated. Gd 2 O 3 :Eu and Y 2 O 3 :Eu have been found to possess prominent TL phenomena. A stable high temperature glow peak has been found at 345 o C in the cubic (C type) crystalline structure of Gd 2 O 3 :Eu. A more stable high temperature glow peak has also been found at about 380 o C in Y 2 O 3 :Eu. The sensitivity is high enough to be used as UV sensors. TL phenomena in Gd 2 O 3 :Tb and Gd 2 O 3 :Dy have also been investigated, but their TL intensities are much weaker than that of Gd 2 O 3 :Eu or Y 2 O 3 :Eu. On the other hand, all glow peaks of Gd 2 O 3 :Tb and Gd 2 O 3 :Dy are unstable at room temperature, therefore, Gd 2 O 3 :Tb and Gd 2 O 3 :Dy are not suitable for use as UV detectors. According to the above properties, the C type (cubic) crystalline structure of the Gd 2 O 3 :Eu phosphor seems to possess the potential of being the TL material for UV measurement. The position of the high temperature glow peak depends on the total UV exposure. It locates at about 380 o C when this phosphor was irradiated by 302 nm UV at 2.4 mJ.cm -2 exposure, but it shifts to 345 o C at 19.2 mJ.cm -2 or higher exposure. The response curves of this phosphor for various wavelengths, e.g. 253.7 nm, 302 nm, and 365 nm, were also measured. This phosphor is sensitive enough to measure background UV radiations, such as sunlight, bulb light etc. (author)

  7. Alpha alumina exoemissive and thermoluminescent properties. Application to the dosimetry of ionizing radiations in case of accident

    International Nuclear Information System (INIS)

    Alessandri, M.F.

    1989-06-01

    This work consists of two parts. In the first part, a phenomenon of phototransfer in Thermostimulated Exoelectronic Emission (T.S.E.E.) is pointed out. Study of intrinsic T.S.E.E. of alpha alumina exposed to ultraviolet (U.V.) excitation of energy superior to 4 eV shows three T.S.E.E. peaks situated at 240, 325, 535 0 C (heating rate of 2 0 C.s -1 ). The phototransfer phenomenon is then characterized notably by the lowering of the U.V. excitation threshold to 3.5 eV and the increasing of T.S.E.E. response for U.V. energies between 3.5 and 6 eV. Discussion and interpretation of the results obtained are based on the perfect analogy with the phototransfer of Thermoluminescence (T.L.) observed on a similar type of alpha alumina. The second part describes the application of alpha alumina dosimetric properties to accidental irradiation dosimetry and cartography. The material is bound to a textile support to be used for clothes manufacturing for irradiation risking workers. T.S.E.E. and T.L. properties of the selected fabric have been studied. - T.S.E.E. response to a beta irradiation of strontium 90 covers the region [0.01 - 10 Gy], with a dispersion of ± 20%, a non significant thermic fading beyond 72 hours after irradiation and a very important optical fading; - the region in T.L. extends from 0.25 to 10 Gy with X irradiation (45 kV) and from 0.5 to 10 Gy with gamma irradiation of cobalt 60 and caesium 137; the dispersion is ± 20%, the thermic fading is weak and the optical fading is negligible in artificial light or does not vary any more after 5 days of sunlight exposition [fr

  8. Study of the reliability of the TLDs reader in a Thermoluminescent dosimetry laboratory

    International Nuclear Information System (INIS)

    Silva F, J.C. da; Fonseca, H.G. da

    2006-01-01

    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

  9. Type test of the Rados MTS-N thermoluminescent dosimetry system for individual monitoring of whole body photons in HP (10)

    International Nuclear Information System (INIS)

    Ferreira, M.S.; Silva, E.R. da; Maurício, C.L.P.

    2017-01-01

    The Institute of Radioprotection and Dosimetry (IRD/CNEN-RJ), uses an automatic thermoluminescent dosimetry (TL) system for evaluation of whole body for photons with individual monitors RADOS MTS-N, with TLF detector of LiF: Mg, Ti. The objective of this work was to characterize this system for the evaluation of H P (10) operating magnitude. The measuring range is 0.2 mSv to 2 Sv, for photon energies from 20 keV to 1250 keV. Performance tests were done for the following characteristics: homogeneity of the monitors, system reproducibility, linearity, temperature and humidity effect, energy and angular dependence and fading. The acceptance requirements used to test system performance have been drawn from national and international documents. The results obtained prove that the system can be used to measure the occupational dose of photons in H P (10)

  10. Using thermoluminescence dosimetry (TLD) to determine the gonadal dose of patients under-going chest X-ray examinations at NKST hospital, Mkar

    International Nuclear Information System (INIS)

    Agba, E.H.; Akaagerger, N.B.; Kungur, S.T.

    2011-01-01

    The doses absorbed by the gonads of patients undergoing chest X-ray examinations at NKST Christian Hospital, Mkar was determined using the Thermoluminescence Dosimetry Technique of measurement. Also, the direct X-ray dose to the chest of patients undergoing the routine examinations was also determined using the Thermolumnescence Dosimetry technique of measurement. The mean gonadal dose and the X-ray dose to the patients were found to be 0.03±0.02μSv and 0.04±0.03mSv respectively after exposure. These X-ray doses to the patients is seen to be within the acceptable recommended X -ray dose limits of 1mGy recommended by ICRP.

  11. 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)

  12. Optimization of the preparation method of LiF: Mg, Cu, P and study of its thermoluminescent properties to be used in ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.

    1995-01-01

    In this thesis the preparation and dosimetric properties of the thermoluminescence phosphor LiF doped with magnesium, copper and phosphorus are studied. In chapter 1 luminescence phenomenon in solids is described, emphasizing the importance of thermally stimulated luminescence known as thermoluminescence (TL) as well as its application in ionizing radiation dosimetry. The models used to determine the kinetics parameters in the TL phenomenon are described in chapter 2. In chapter 3, the dosimetric characteristics of a TL materials and its requirements for dosimetry are analyzed. The preparation method of LiF: Mg, Cu, P is presented in chapter 4 studying its general characteristics for dosimetry. The concentrations of dopants, glow curve structure, TL response to gamma, beta and alpha exposures are studied along with those of LiF: Mg, Cu, P prepared for other authors and with those of LiF: Mg, Ti (TLD-100). The kinetic parameters of the phosphor were determined by the deconvolution method. Pellets of this new phosphor powder were made by pressing it at room temperature and sintering in inert atmosphere at 700 Centigrade degrees. Dosimetric characteristics of these pellets were also studied. Chapter 5 presents the results and conclusions of this study. The new dosimeter exhibited three peaks in its glow curve at 140, 180 and 220 Centigrade degrees respectively. Its TL response to gamma radiation was linear from 43.5 μ Gy to 100 Gy. This dosimeter is reusable and stable without significant loss of sensitivity. Its sensitivity was about 30 times higher than that of TLD-100. Fading of this dosimeter was negligible at room temperature as well as at body temperature (37 Centigrade degrees), and 65% at 60 Centigrade degrees. In conclusion, this dosimeter meets all the requirements of the ANSI standard. These and other characteristics render this dosimeter useful in diverse applications of radiation dosimetry. (Author)

  13. Thermoluminescent dosimetry and of optically stimulated luminescence of diamond films grown up by the chemical vapor deposition technique exposed to beta radiation

    International Nuclear Information System (INIS)

    Melendrez A, R.; Barboza F, M.

    2002-01-01

    A study of the dosimetric properties through the thermoluminescence (Tl) and Optically stimulated luminescence (Lobe) in diamond films grown up by the chemical vapor deposition (Dq) techniques was realized.The films under study have thickness of 6, 12, 180 and 500 microns. The dose range was from 0 to 1.5 KGy, observing for the case of the thermoluminescent dosimetry a linear behavior in the range 0-300 Gy and a supra linearity effect in the range from 300-1500 Gy. For the case of the dosimetry by means of LOE a linear behavior in the range (0-300 Gy) without be enough for the saturation was observed, although some samples exhibit a linear behavior until 1500 Gy (6 microns). The irradiation was realized with a source of Strontium 90 of (40 mCi) and the photoestimulation for realizing the measures of LOE was realized using diodes emitting of laser light (470 nm) which generate until 50 MW/cm 2 . The Tl peak which was used to realize the dosimetry such Tl as LOE was that located around 340 C degrees in the brilliance curve which presents another peaks centered around of 110, 190, and 340 C degrees, depending on the film. It was realized a study of the Tl signal drop and it was observed that after 3 hours the signal was stable reaching a decay of 15 %. the analysis of the drop in the Tl signal, immediately after to irradiate and after to photoestimulate with the blue light laser for observing the LOE, indicated that exists a fall in all the Tl peaks, decaying in greater proportion those of more low temperature. (Author)

  14. Thermoluminescence kinetic analysis and dosimetry features of MgSO4:Dy and MgSO4:Cu nano-rods

    International Nuclear Information System (INIS)

    Zahedifar, M.; Almasifard, F.; Sadeghi, E.; Biroon, M. Kashefi; Ramazani- Moghaddam-Arani, A.

    2016-01-01

    MgSO 4 :Dy and MgSO 4 :Cu nano-rods (NRs) were synthesized for the first time by semi co- precipitation method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) were utilized for sample characterization. The optimum amount of dysprosium and copper concentrations were obtained both at 0.1 mol% in MgSO 4 :Dy and MgSO 4 :Cu NRs. T m -T stop and computerized glow curve deconvolution (CGCD) methods were used for identifying the number of component glow peaks and kinetic parameters of the synthesized NRs. Initial rise and variable heating rate methods were also used to ensure the reliability of obtained kinetic parameters. Results show that the TL sensitivity of MgSO 4 :Dy is about 7 times more than that of magnesium sulfate doped with Cu. The TL dose response of MgSO 4 :Dy and MgSO 4 :Cu NRs are linear up to absorbed dose of 10 KGy. Other TL dosimetry characteristics of the produced NRs are also presented and discussed. - Highlights: • MgSO4:Dy and MgSO4:Cu nano-rods were synthesized for the first time. • Thermoluminescence dosimetry properties were studied. • The nano-phosphors showed linear dose response up to very high dose levels. • The synthesized nano-rods have potential application for high dose dosimetry.

  15. Development of Mg B4 O7:Dy thermoluminescent solid dosemeter for using on the thermal neutron dosimetry

    International Nuclear Information System (INIS)

    Potiens Junior, A.J.; Campos, L.L.; Todo, A.S.

    1992-01-01

    The magnesium tetraborate doped with dysprosium (Mg B 4 O 7 :O y ) thermoluminescent phosphor is developed, containing boron, which boron 10 isotope has high cross section for thermal neutrons by 10 B (n,α) 7 Li reaction. The nitric acid concentration, the number of washing for removing the excess of boric acid, the powder granulation of Mg B 4 O 7 :O y , the percentage of teflon used as binder and the reproducibility of thermoluminescent answer are also presented. (C.G.C.)

  16. Thermoluminescent properties of polycrystalline carbon doped LaAlO3/La(OH)3 crystals synthesized by solid state reaction for application in UV dosimetry

    International Nuclear Information System (INIS)

    Alves, N.; Oliveira de F, L.; Barbosa F, W.

    2017-10-01

    It is well known that UV radiation can induce certain deleterious effects, such as erythema, painful inflammation of the membrane of the eye and skin cancer. Therefore, it has been pushing the research for producing new and high performance UV sensitive Tl materials. There is an increasing interest in the development of new Tl materials for ultraviolet (UV) dosimetry purposes, owing to simplicity of the sample readout compared to other techniques. In this paper, thermoluminescence and dosimetric characteristics of pure and carbon doped lanthanum aluminate and hydroxide lanthanum crystals, irradiated with different UV doses, were studied and discussed. All samples studied were produced by solid state reaction method with different mixing methodologies. Characterization of sintered powders by X-ray diffraction, UV-Vis spectrophotometry and Ftir spectroscopy were performed. XRD data confirmed the LaAlO 3 and La(OH) 3 crystalline phases. The thermoluminescent study revealed that all compositions presented high UV sensibility. The sample which was grown by first sintering La 2 O 3 together carbon atoms and then sintering again in order to obtain La 2 O 3 :C together Al 2 O 3 , presented the best linear dose response over UV doses ranging from 0.042 to 0.63 mJ/cm 2 , with correlation coefficients equal to 0.99931. The synthesis methodology used was very efficient to obtain crystals with high Tl output intensities for low exposure rate UV R fields. (Author)

  17. Effect of co-doping of sodium on the thermoluminescence dosimetry properties of copper-doped zinc lithium borate glass system

    International Nuclear Information System (INIS)

    Saidu, A.; Wagiran, H.; Saeed, M.A.; Alajerami, Y.S.M.; Kadir, A.B.A.

    2016-01-01

    The effect of sodium as a co-dopant on the thermoluminescence (TL) properties of copper-doped zinc lithium borate (ZLB: Cu) subjected to Co-60 gamma radiation is reported in this study. TL intensity is enhanced with the introduction of sodium in ZLB: Cu. The obtained glow curve is simple with a single peak. The annealing procedure and the best heating rate for the proposed thermoluminescent dosimeter (TLD) are established, and the phosphor is reusable. The TL response within the dose range of 0.5–1000 Gy is investigated. The results show that the thermal fading behaviour is improved significantly. - Highlights: • Dosimetry properties of an improved TL dosimeter. • The dosimeter is made of lithium borate, modified with ZnO, doped with CuO and co-doped with Na 2 O. • With addition of Na to Cu in the ZLB host, TL yield and sensitivity has significantly enhanced. • The fading behaviour has also been minimized significantly. • The new material is also characterized with the linear dose response, and good reproducibility behaviour.

  18. 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)

  19. Thermoluminescent properties of polycrystalline carbon doped LaAlO{sub 3}/La(OH){sub 3} crystals synthesized by solid state reaction for application in UV dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alves, N.; Oliveira de F, L. [Federal University of the State of Minas Gerais, Department of Nuclear Engineering, Av. Pres. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Barbosa F, W., E-mail: neire.radiologia@yahoo.com.br [Nuclear Technology Development Center, 941, 30161-970 Belo Horizonte, Minas Gerais (Brazil)

    2017-10-15

    It is well known that UV radiation can induce certain deleterious effects, such as erythema, painful inflammation of the membrane of the eye and skin cancer. Therefore, it has been pushing the research for producing new and high performance UV sensitive Tl materials. There is an increasing interest in the development of new Tl materials for ultraviolet (UV) dosimetry purposes, owing to simplicity of the sample readout compared to other techniques. In this paper, thermoluminescence and dosimetric characteristics of pure and carbon doped lanthanum aluminate and hydroxide lanthanum crystals, irradiated with different UV doses, were studied and discussed. All samples studied were produced by solid state reaction method with different mixing methodologies. Characterization of sintered powders by X-ray diffraction, UV-Vis spectrophotometry and Ftir spectroscopy were performed. XRD data confirmed the LaAlO{sub 3} and La(OH){sub 3} crystalline phases. The thermoluminescent study revealed that all compositions presented high UV sensibility. The sample which was grown by first sintering La{sub 2}O{sub 3} together carbon atoms and then sintering again in order to obtain La{sub 2}O{sub 3}:C together Al{sub 2}O{sub 3}, presented the best linear dose response over UV doses ranging from 0.042 to 0.63 mJ/cm{sup 2}, with correlation coefficients equal to 0.99931. The synthesis methodology used was very efficient to obtain crystals with high Tl output intensities for low exposure rate UV R fields. (Author)

  20. Thermoluminescence and radioluminescence properties of tissue equivalent Cu-doped Li{sub 2}B{sub 4}O{sub 7} for radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E.; Furetta, C. [UNAM, Instituto de Ciencias Nucleares, Apdo. Postal 70543, 04510 Mexico D. F. (Mexico); Marcazzo, J.; Santiago, M. [Instituto de Fisica Arroyo Seco / UNICEN, Gral. Pinto 399, 7000 Tandil, Buenos Aires (Argentina); Guarneros, C. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Altamira Km 14.5, 896000 Altamira, Tamaulipas (Mexico); Pacio, M. [Benemerita Universidad Autonoma de Puebla, Instituto de Ciencias, Centro de Investigacion en Dispositivos Semiconductores, Av. 14 Sur, 72570 Puebla, Pue. (Mexico); Palomino, R., E-mail: ecruz@nucleares.unam.mx [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Fisico-Matematicas, Av. San Claudio y 18 Sur, 72570 Puebla Pue. (Mexico)

    2015-10-15

    Thermoluminescence (Tl) and radioluminescence (Rl) properties of lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) doped with different concentration of copper (0.25, 0.5, 1 wt %) under gamma and beta irradiation has been investigated. The feasibility of using this borate in radiation dosimetry at low doses has been evaluated. Tissue equivalent Li{sub 2}B{sub 4}O{sub 7} was prepared by solid state reaction using mixing stoichiometric compositions of lithium carbonate (Li{sub 2}CO{sub 3}) and boric acid (H{sub 3}BO{sub 3}) and a solution of CuCl{sub 2} as dopant. The glow curve, of the most efficient copper doped borate (Li{sub 2}B{sub 4}O{sub 7}:Cu 0.5 wt %), shows a main stable peak centered at 225 degrees C and a second low temperature peak centered at 80 degrees C. The low temperature peak disappears completely after 24 hours of storage in darkness and at room temperature or after an annealing at 120 degrees C for 10 seconds. The main peak of the Li{sub 2}B{sub 4}O{sub 7}:Cu remains constant. The Tl response of Li{sub 2}B{sub 4}O{sub 7}:Cu shows good linearity in the analyzed dose range. The stability and repeatability of Rl signals of the borate have been studied and the Li{sub 2}B{sub 4}O{sub 7}:Cu (0.5 wt %) shown the higher Rl emission and a stable and repetitive response. Results show that Li{sub 2}B{sub 4}O{sub 7}:Cu has prospects to be used in gamma and beta radiation dosimetry. (Author)

  1. 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)

  2. Applicability of thermoluminescent dosimeters in X-ray organ dose determination and in the dosimetry of systemic and boron neutron capture radiotherapy

    International Nuclear Information System (INIS)

    Aschan, C.

    1999-01-01

    The main detectors used for clinical dosimetry are ionisation chambers and semiconductors. Thermoluminescent (TL) dosimeters are also of interest because of their following advantages: (i) wide useful dose range, (ii) small physical size, (iii) no need for high voltage or cables, i.e. stand alone character, and (iv) tissue equivalence (LiF) for most radiation types. TL detectors can particularly be used for the absorbed dose measurements performed with the aim to investigate cases where dose prediction is difficult and not as part of a routine verification procedure. In this thesis, the applicability of TL detectors was studied in different clinical applications. Particularly, the major phenomena (e.g. energy dependence, sensitivity to high LET radiation, reproducibility) affecting on the precision and accuracy of TL detectors in the dose estimations were considered in this work. In organ dose determinations of diagnostic X-ray examinations, the TL detectors were found to be accurate within 5% (1 S.D.). For in viva studies using internal irradiation source, i.e. for systemic radiation therapy, a method for determining the absorbed doses to organs was introduced. The TL method developed was found to be able to estimate the absorbed doses to those critical organs near the body surface within 50%. In the mixed neutron-gamma field of boron neutron capture therapy (BNCT), TL detectors were used for gamma dose and neutron fluence measurements. They were found able to measure the neutron dose component with the accuracy of 16%, and therefore to be a useful addition to the activation foils in BNCT neutron dosimetry. The absorbed gamma doses can be measured with TL detectors within 20% in the mixed neutron-gamma field, which enables in viva measurements at BNCT beams with approximately the same accuracy. In this study, the uncertainties of TL dosimeters were found to be high but not essentially greater than those in other measurement techniques used for clinical dosimetry

  3. Dosimetry

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The purpose of ionizing radiation dosimetry is the measurement of the physical and biological consequences of exposure to radiation. As these consequences are proportional to the local absorption of energy, the dosimetry of ionizing radiation is based on the measurement of this quantity. Owing to the size of the effects of ionizing radiation on materials in all of these area, dosimetry plays an essential role in the prevention and the control of radiation exposure. Its use is of great importance in two areas in particular where the employment of ionizing radiation relates to human health: radiation protection, and medical applications. Dosimetry is different for various reasons: owing to the diversity of the physical characteristics produced by different kinds of radiation according to their nature (X- and γ-photons, electrons, neutrons,...), their energy (from several keV to several MeV), the orders of magnitude of the doses being estimated (a factor of about 10 5 between diagnostic and therapeutic applications); and the temporal and spatial variation of the biological parameters entering into the calculations. On the practical level, dosimetry poses two distinct yet closely related problems: the determination of the absorbed dose received by a subject exposed to radiation from a source external to his body (external dosimetry); and the determination of the absorbed dose received by a subject owing to the presence within his body of some radioactive substance (internal dosimetry)

  4. Dosimetry

    International Nuclear Information System (INIS)

    Rezende, D.A.O. de

    1976-01-01

    The fundamental units of dosimetry are defined, such as exposure rate, absorbed dose and equivalent dose. A table is given of relative biological effectiveness values for the different types of radiation. The relation between the roentgen and rad units is calculated and the concepts of physical half-life, biological half-life and effective half-life are discussed. Referring to internal dosimetry, a mathematical treatment is given to β particle-and γ radiation dosimetry. The absorbed dose is calculated and a practical example is given of the calculation of the exposure and of the dose rate for a gama source [pt

  5. Polynomial expressions of electron depth dose as a function of energy in various materials: application to thermoluminescence (TL) dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Deogracias, E.C.; Wood, J.L.; Wagner, E.C.; Kearfott, K.J

    1999-02-11

    The CEPXS/ONEDANT code package was used to produce a library of depth-dose profiles for monoenergetic electrons in various materials for energies ranging from 500 keV to 5 MeV in 10 keV increments. The various materials for which depth-dose functions were derived include: lithium fluoride (LiF), aluminium oxide (Al{sub 2}O{sub 3}), beryllium oxide (BeO), calcium sulfate (CaSO{sub 4}), calcium fluoride (CaF{sub 2}), lithium boron oxide (LiBO), soft tissue, lens of the eye, adiopose, muscle, skin, glass and water. All materials data sets were fit to five polynomials, each covering a different range of electron energies, using a least squares method. The resultant three dimensional, fifth-order polynomials give the dose as a function of depth and energy for the monoenergetic electrons in each material. The polynomials can be used to describe an energy spectrum by summing the doses at a given depth for each energy, weighted by the spectral intensity for that energy. An application of the polynomial is demonstrated by explaining the energy dependence of thermoluminescent detectors (TLDs) and illustrating the relationship between TLD signal and actual shallow dose due to beta particles.

  6. Thermal neutrons thermoluminescence dosimetry using CaF2 + KBr e CaSO4: Dy + Br

    International Nuclear Information System (INIS)

    Leite, A.M.P.

    1979-01-01

    Cold-pressed samples of CaF 2 + KBr and CaSO 4 :Dy + KBr have been used in the thermal neutron detection by the thermoluminescence technique. The amount of 100 mg of the TL phosphor added to 80 mg of KBr showed to be the optimum mixture regarding sensitivity as well as the handling of the dosimeters. The detection is based on the self-irradiation of the phosphor by the Br isotopes activated by exposure to a neutron-gama field. The prompt dose and consequentely the gama contribution are erased by post-irradiation thermal annealing. A linear dependence has been found between the TL self-induced signal and the thermal neutron flux in the range 10 6 n.cm -2 .seg -1 -10 -12 n.cm -2 .seg -1 . The minimum detectable fluence has benn determined as 10 9 n.cm -2 and 10 6 n.cm -2 using pellets of CaF 2 + KBr and CaSO 4 :Dy + KBr, respectively. The main results suggest the use of CaSO 4 :Dy + KBr pellets and TL as a complementary technique for thermal neutron detection. (author) [pt

  7. Verification of the dose in the inspection modules of Co-60 from Mexicali, B.C.N. through thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Cruz C, D.; Azorin, J.; Rivera, T.

    2005-01-01

    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 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 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. (Author)

  8. Deriving staff and public doses in a PET/CT facility from measured radiation levels using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Al-Haj, A. N.; Lobriguito, A. M.; Arafah, A.; Parker, R.

    2011-01-01

    The introduction of PET/CT at King Faisal Specialist Hospital and Research Centre for whole body and brain imaging has become favourable for diagnosis of cancer. There is no data available on the PET/CT dose to staff and members of the public for different activities of 18 F [fluorodeoxyglucose (FDG)] and for longer patient holding time. The study aims to determine and evaluate staff and public doses by using thermoluminescent dosemeters monthly readings for a 7-month deployment period and by using direct measurements of dose rates at 30 cm and 1 m distances from the patients after injection. The whole body doses per procedure and per administered activity of 18 F (FDG) were estimated. A dose map inside the PET/CT was generated to provide information of the dose levels in different locations. The Pearson correlation showed a strong correlation (r 2 = 0.71) between the dose per activity and the number of patients. Optimisation of radiation protection of staff and members of the public was investigated and recommendations were given. (authors)

  9. Thermoluminescence dosimetry properties and kinetic parameters of lithium potassium borate glass co-doped with titanium and magnesium oxides

    International Nuclear Information System (INIS)

    Hashim, S.; Alajerami, Y.S.M.; Ramli, A.T.; Ghoshal, S.K.; Saleh, M.A.; Abdul Kadir, A.B.; Saripan, M.I.; Alzimami, K.; Bradley, D.A.; Mhareb, M.H.A.

    2014-01-01

    Lithium potassium borate (LKB) glasses co-doped with TiO 2 and MgO were prepared using the melt quenching technique. The glasses were cut into transparent chips and exposed to gamma rays of 60 Co to study their thermoluminescence (TL) properties. The TL glow curve of the Ti-doped material featured a single prominent peak at 230 °C. Additional incorporation of MgO as a co-activator enhanced the TL intensity threefold. LKB:Ti,Mg is a low-Z material (Z eff =8.89) with slow signal fading. Its radiation sensitivity is 12 times lower that the sensitivity of TLD-100. The dose response is linear at doses up to 10 3 Gy. The trap parameters, such as the kinetics order, activation energy, and frequency factor, which are related to the glow peak, were determined using TolAnal software. - Highlights: • Lithium potassium borate glass doped with Ti and Mg was prepared. • The material is close to soft tissues in terms of Zeff. • The radiation sensitivity is about 12 times lower than that of TLD-100. • The signal fades about 8% in 10 days and 17% in 3 months

  10. Evaluation of thermoluminescent dosimeters (TLDs) of two different designs for beta particle and low energy photon dosimetry

    International Nuclear Information System (INIS)

    Nugent, K.J.; Ahmed, A.B.; Groer, P.G.

    1992-11-01

    The purpose of this research was to compare the response of the thermoluminescent dosimeters (TLDs) currently used at Martin Marietta Energy Systems with that of a newly designed TLD which is now under consideration. The new TLD consists of a thicker chip in element No. 3 and a thinner, more opaque mylar filter over this same element. The goals were to determine if the new (proposed) TLD would perform significantly different from the old (current) TLD when measuring dose equivalents from beta particles and low energy photons (x-rays) and to find out if changing from the old to the new design would require that modifications be made to the calibration factors currently used in the dose calculation algorithm. To accomplish these objectives, tests were performed using both types of dosimeters placed under identical conditions. Their responses were then compared and analyzed. It was concluded that the new TLDs would allow for the detection of lower levels of radiation and give more precise readouts at very low (i.e., background) levels in addition to the obvious advantages of the new design, such as, a thicker, more durable chip and a more opaque mylar. It was also determined that no adjustments to the calibration factors would be necessary in switching to the new design

  11. Numerical analysis of thermoluminescence glow curves

    International Nuclear Information System (INIS)

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

    1989-01-01

    This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs

  12. 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)

  13. 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)

  14. CaSO4:DY,Mn: A new and highly sensitive thermoluminescence phosphor for versatile dosimetry

    Science.gov (United States)

    Bahl, Shaila; Lochab, S. P.; Kumar, Pratik

    2016-02-01

    With the advent of newer techniques for dose reduction coupled with the development of more sensitive detectors, the radiation doses in radiological medical investigation are decreasing. Nevertheless, keeping the tenet in mind that all radiation doses could entail risk, there is a need to develop more sensitive dosimeters capable of measuring low doses. This paper gives the account of the development of a new and sensitive phosphor CaSO4:Dy,Mn and its characterization. The standard production procedure based on the recrystallization method was used to prepare CaSO4:Dy,Mn. The Thermoluminescence (TL) studies were carried out by exposing it with gamma radiation (Cs-137) from 10 μGy to 100 Gy. The theoretical studies to determine the number of peaks and kinetic parameters related to the TL glow peaks in CaSO4:Dy,Mn was performed using the Computerized Glow Curve Deconvolution (CGCD) method. Experiments were performed to determine optimum concentration of the dopants Dysprosium (Dy) and Mangnese (Mn) in the host CaSO4 so that maximum sensitivity of the phosphor may be achieved. The optimum dopant concentration turned out to be 0.1 mol%. As there were two dopants Dy and Mn their relative ratio were varied in steps of 0.025 keeping the concentration of total dopant (Dy and Mn) 0.1 mol% always. The maximum TL intensity was seen in the CaSO4:Dy(0.025),Mn(0.075) combination. The TL sensitivity of this phosphor was found to be about 2 and 1.8 times higher than that of popular phosphor CaSO4:Dy and LiF:Mg,Cu,P (TLD-700H) respectively. This new phosphor CaSO4:Dy,Mn showed fading of 11% which is similar to that of the standard phosphor CaSO4:Dy. The paper concludes that the new, highly sensitive TL phosphor CaSO4:Dy,Mn has shown higher sensitivity and hence the potential to replace commonly used CaSO4:Dy.

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

    International Nuclear Information System (INIS)

    Almeida, Shirlane Barbosa de

    2017-01-01

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

  17. 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)

  18. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  19. 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)

  20. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-15

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, gamma) process in Na sup 2 sup 3 , giving rise to Na sup 2 sup 4 , which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na sup 2 sup 4 , is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na sup 2 sup 3 in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na sup 2 sup 4 /Na sup 2 sup 3 in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R sub B reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzmann transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given

  1. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-01

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, {gamma}) process in Na{sup 23}, giving rise to Na{sup 24}, which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na{sup 24}, is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na{sup 23} in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na{sup 24}/Na{sup 23} in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R{sub B} reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzman transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given. A summary of the 4{pi

  2. 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)

  3. Evaluation of the thermoluminescent detector answers of CaSO4:Dy, LiF:Mg,Ti and micro LiF:Mg,Ti in photon clinical beams dosimetry using water simulator

    International Nuclear Information System (INIS)

    Matsushima, Luciana C.; Veneziani, Glauco R.; Campos, Leticia L.

    2011-01-01

    This paper perform the comparative study of thermoluminescent answer of calcium sulfate dosemeter doped with dysprosium (DaSO 4 :Dy) produced by the IPEN, Sao Paulo, with answer of lithium fluoride dosemeters doped with magnesium and titanium (LiF:Mg, Ti) in the dosimetry of clinical beams of photons (6 and 15 MV) by using water simulator object. Dose-answer curves were obtained for gamma radiation of cobalt-60 in the air and in conditions of electronic equilibrium (plate of PMMA), and clinical photons of CLINAC model 2100C accelerators of the two evaluated hospitals: Hospital das Clinicas of the Faculty of Medicine of Sao Paulo university and Hospital Albert Einstein. It was also evaluated the sensitivity and reproduction of the three dosemeters

  4. Personnel monitoring of radiations with thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Miano, S.C.

    1987-01-01

    The basics of personnel dosimetry technics, used by the Radiologic Protetion and Assessorie Service (SAPRA) are presented, consisting on use of thermoluminescent and CaSO 4 :Dy monitors in aggregated pellets by Teflon. The characteristics of this dosemeters, relating to the sensitivity, energetic dependence, spike temperature, characteristic emission curve, decay and light effect are shown. The thermoluminescent dosemeter measure system and the personnel monitoring system are also described. (C.G.C.) [pt

  5. Personal radiation monitoring with thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Miano, S.C.

    1987-01-01

    The technique of personal dosimetry used by SAPRA (Servico de Assessoria e Protecao Radiologica S/C Ltda., Brazil) is presented. Thermoluminescent monitors and CaSO 4 : Dy are used in pastilles united by teflon. Characteristics of the dosemeters are briefly reported. The system of thermoluminescent measurement, designed and constructed by SAPRA, and the system of personal monitoring are described. (M.A.C.) [pt

  6. Unraveling thermoluminescence

    CERN Document Server

    Sunta, C M

    2014-01-01

    The book is essentially about the theoretical aspects of thermoluminescence (TL). It is structured and written in a manner which will specially be of interest to the fresh undergraduate students and young researchers planning to take up work in the field of thermoluminescence. It is arranged into seven chapters, starting with the historical growth of the subject of TL and an overview of the luminescence phenomena. A Physical model involving thermally disconnected deep traps is specially described. Using this model expressions are derived for the TL intensity growth curve, the supralinearity fa

  7. Carbon doped lanthanum aluminate (LaAlO3:C) synthesized by solid state reaction for application in UV thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Alves, N.

    2015-01-01

    In this work we discuss the TL output for LaAlO 3 :C crystals grown by using three different combinations of Al 2 O 3 , La 2 O 3 and carbon atoms during the synthesis process. Recently, LaAlO 3 single crystals, co-doped with Ce 3+ and Dy 3+ rare earth trivalent ions and grown under hydrothermal conditions, have been reported to show high thermoluminescent response (TL) when exposed to low levels of ultraviolet radiation (UVR). However, undoped LaAlO 3 synthesized by solid state reaction method from the 1:1 mixture of aluminum and lanthanum oxide under reducing atmosphere revealed to have still higher thermoluminescent sensitivity to UV photon fields than the co-doped with Ce 3+ and Dy 3+ . It is well known that carbon doped aluminum oxide monocrystals have excellent TL and photoluminescent response properties for X-rays, UV and gamma radiation fields. Thus, we conducted three different syntheses of LaAlO 3 by this solid state reaction method, doping the mixture with carbon. The lanthanum aluminate polycrystals were synthesized from the 1:1 mixture of aluminum and lanthanum oxide, adding 0.1wt.% carbon and annealed at 1700°C for two hours in hydrogen atmosphere. The X-ray diffraction analysis revealed the formation of rhombohedral LaAlO 3 crystallographic phase, however a small percentage (15%) of Al 2 O 3 has been also identified. The UV-Vis absorbance spectra were obtained and F and F + - center were ascribed. The UV irradiations were carried out using a commercial 8W UV lamp. Thermoluminescence measurements were performed at a Harshaw 4500 TL reader. All compositions investigated have shown high TL sensitivity to UVR. (author)

  8. Testing of CaSO-4:Dy in teflon discs as a thermoluminescent dosimetry material for personal monitoring of uranium mine and mill workers

    International Nuclear Information System (INIS)

    Boas, J.F.; Murray, A.; Young, J.G.; Johnston, P.N.

    1981-05-01

    Some studies of the spectroscopic and thermoluminescent properties of CaSO 4 :Dy are discussed. Measurements were also made in the field. Exposures measured using TLD, film and spot monitoring were in agreement, and these observations, together with measurements made at various heights above the ore stockpile have shown that CaSO 4 :Dy in teflon discs, shielded by 2mm of copper, give a reliable measure of the exposure at the appropriate position on the wearer's body. This exposure may then be converted into the dose equivalent for the whole body

  9. Dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Musilek, L.; Seda, J.; Trousil, J.

    1992-01-01

    The publication deals with a major field of ionizing radiation dosimetry, viz., integrating dosimetric methods, which are the basic means of operative dose determination. It is divided into the following sections: physical and chemical effects of ionizing radiation; integrating dosimetric methods for low radiation doses (film dosimetry, nuclear emulsions, thermoluminescence, radiophotoluminescence, solid-state track detectors, integrating ionization dosemeters); dosimetry of high ionizing radiation doses (chemical dosimetric methods, dosemeters based on the coloring effect, activation detectors); additional methods applicable to integrating dosimetry (exoelectron emission, electron spin resonance, lyoluminescence, etc.); and calibration techniques for dosimetric instrumentation. (Z.S.). 422 refs

  10. Thermoluminescence dosimeters with narrow bandpass filters

    Science.gov (United States)

    Walker, Scottie W.

    2004-07-20

    A dosimetry method exposes more than one thermoluminescence crystals to radiation without using conventional filters, and reads the energy stored in the crystals by converting the energy to light in a conventional manner, and then filters each crystal output in a different portion of the spectrum generated by the crystals.

  11. Standard practice for application of thermoluminescence-dosimetry (TLD) systems for determining absorbed dose in radiation-hardness testing of electronic devices. ASTM standard

    International Nuclear Information System (INIS)

    1998-05-01

    This practice is under the jurisdiction of ASTM Committee E-10 on Nuclear Technology and Applications and is the direct responsibility of Subcommittee E10.07 on Radiation Dosimetry for Radiation Effects on Materials and Devices. Current edition approved Jun. 10, 1997. Published May 1998. Originally published as E 668-78. Last previous edition E 668-93

  12. Thermoluminescent phosphor

    Science.gov (United States)

    Lasky, Jerome B.; Moran, Paul R.

    1978-01-01

    A thermoluminescent phosphor comprising LiF doped with boron and magnesium is produced by diffusion of boron into a conventional LiF phosphor doped with magnesium. Where the boron dopant is made to penetrate only the outer layer of the phosphor, it can be used to detect shallowly penetrating radiation such as tritium beta rays in the presence of a background of more penetrating radiation.

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

    International Nuclear Information System (INIS)

    Bravim, Amanda

    2015-01-01

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

  14. Assessment of CaSO{sub 4}:Dy and LiF:Mg,Ti thermoluminescent dosimeters performance in the dosimetry of clinical electron beams; Avaliacao do desempenho dos detectores termoluminesncetes de CaSO{sub 4}:Dy e LiF:Mg,Ti na dosimetria de feixes clinicos de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Maira Goes

    2008-07-01

    The assessment of the performance of CaS0{sub 4}:Dy thermoluminescent detectors produced by IPEN in the dosimetry of clinical electron beams aims to propose an alternative to the LiF:Mg,Ti commercial dosimeters (TLD-100) largely applied in radiation therapy. The two types of thermoluminescent dosimeters were characterised with the use of PMMA, RMI-457 type solid water and water phantoms in radiation fields of 4, 6, 9, 12 and 16 MeV electrons of nominal energies in which the dose-response curves were obtained and the surface and depth doses were determined. The thermoluminescent response dependency with the electron nominal energies and the applied phantom were studied. The CaS0{sub 4}:Dy presented the same behaviour than the LiF:Mg,Ti in such a way that its application as an alternative to the TLD-100 pellets in the radiation therapy dosimetry of electron beams is viable and presents the significantly higher sensitivity to the electron radiation as its main advantage. (author)

  15. Neutron Dosimetry

    International Nuclear Information System (INIS)

    Vanhavere, F.

    2001-01-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding

  16. Neutron Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Vanhavere, F

    2001-04-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding.

  17. Background radiation accumulation and lower limit of detection in thermoluminescent beta-gamma dosimeters used by the centralized external dosimetry system

    International Nuclear Information System (INIS)

    Sonder, E.; Ahmed, A.B.

    1991-12-01

    A value for ''average background radiation'' of 0.75 mR/week has been determined from a total of 1680 thermoluminescent dosimeters (TLD's) exposed in 70 houses for periods up to one year. The distribution of results indicates a rather large variation among houses, with a few locations exhibiting backgrounds double the general average. Some discrepancies in the short-term background accumulation of TLD's have been explained as being due to light leakage through the dosimeter cases. In addition the lower limit of detection (L D ) for deep and shallow dose equivalents has been determined for these dosimeters. The L D for occupational exposure depends strongly on the time a dosimeter is exposed to background radiation in the field. The L D can vary from a low of 2.4 mrem for high energy gamma rays when the background accumulation period is less than a few weeks to values as high as 66 mrem for uranium beta particles when background has been allowed to accumulate for more than 21 weeks

  18. Characterising an aluminium oxide dosimetry system.

    Science.gov (United States)

    Conheady, Clement F; Gagliardi, Frank M; Ackerly, Trevor

    2015-09-01

    In vivo dosimetry is recommended as a defence-in-depth strategy in radiotherapy treatments and is currently employed by clinics around the world. The characteristics of a new optically stimulated luminescence dosimetry system were investigated for the purpose of replacing an aging thermoluminescence dosimetry system for in vivo dosimetry. The stability of the system was not sufficient to satisfy commissioning requirements and therefore it has not been released into clinical service at this time.

  19. Evaluation of Radiation Exposure to Staff and Environment Dose from [18F]-FDG in PET/CT and Cyclotron Center using Thermoluminescent Dosimetry.

    Science.gov (United States)

    Zargan, S; Ghafarian, P; Shabestani Monfared, A; Sharafi, A A; Bakhshayeshkaram, M; Ay, M R

    2017-03-01

    PET/CT imaging using [18F]-FDG is utilized in clinical oncology for tumor detecting, staging and responding to therapy procedures. Essential consideration must be taken for radiation staff due to high gamma radiation in PET/CT and cyclotron center. The aim of this study was to assess the staff exposure regarding whole body and organ dose and to evaluate environment dose in PET/CT and cyclotron center. 80 patients participated in this study. Thermoluminescence, electronic personal dosimeter and Geiger-Muller dosimeter were also utilized for measurement purpose. The mean annual equivalent organ dose for scanning operator with regard to lens of eyes, thyroid, breast and finger according to mean±SD value, were 0.262±0.044, 0.256±0.046, 0.257±0.040 and 0.316±0.118, respectively. The maximum and minimum estimated annual whole body doses were observed for injector and the chemist group with values of (3.98±0.021) mSv/yr and (1.64±0.014) mSv/yr, respectively. The observed dose rates were 5.67 µSv/h in uptake room at the distance of 0.5 meter from the patient whereas the value 4.94 and 3.08 µSv/h were recorded close to patient's head in PET/CT room and 3.5 meter from the reception desk. In this study, the injector staff and scanning operator received the first high level and second high level of radiation. This study confirmed that low levels of radiation dose were received by all radiation staff during PET/CT procedure using 18F-FDG due to efficient shielding and using trained radiation staff in PET/CT and cyclotron center of Masih Daneshvari hospital.

  20. Study on the thermoluminescent properties of K2YF5 and K2GdF5 crystals doped with optically active trivalent ions for gamma and neutrons dosimetry

    International Nuclear Information System (INIS)

    Silva, Edna Carla da

    2008-01-01

    In this work, the thermoluminescent (TL) properties of both double potassium yttrium fluoride (K 2 YF 5 ) and double potassium gadolinium fluoride (K 2 GdF 5 ) crystals doped with optically active rare earth ions were investigated from the point of view of gamma and neutron dosimetry. Crystalline platelets with thickness of about 1 mm, synthesized under hydrothermal conditions, were irradiated in order to study TL sensitivity, as well as dose and energy response, reproducibility and fading, in terms of Ce 3+ , Tb 3+ , Dy 3+ , e Pr 3+ concentrations. The K 2 YF 5 crystals doped with 1.0 at por cent Dy 3+ have been found to have an excellent linear TL response to X and gamma photons, in the range of 0.01 to 10 mGy. The TL output is comparable to that of CaS0 4 :Mn dosemeters. The main peak at 130 deg C has been found to have a TL response for 41.1 keV X-ray energy 32 times higher than that for 662 keV gamma rays. This fact points out that the K 2 Y 0.99 Dy 0.01 F 5 crystals have great potential for X-rays diagnostic and/or industrial radiography. On the other hand, the K 2 GdF 5 crystals doped with 5.0 at por cent Dy 3+ have been found to have the better TL response for gamma and fast neutron radiation, among the dopants studied. For gamma fields the TL response was linear for doses ranging from 0.1 to 200 mGy. The TL peak around 200 deg C can be deconvoluted into four individual peaks, all of them with linear behavior. For fast neutron radiation produced by an 241 Am B e source, the TL responses for doses ranging from 0.6 to 12 mSv were also linear and comparable to that of commercial TLD-600, irradiated at same conditions. The TL emission due to neutrons was in the high temperature range, above 200 deg C. These results points out that K 2 Gd 0.95 Dy 0.05 F 5 crystals are good candidates for use in neutron dosimetry applications. (author)

  1. 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

  2. Type test of the Rados MTS-N thermoluminescent dosimetry system for individual monitoring of whole body photons in HP (10); Teste de tipo do sistema de dosimetria termoluminescente RADOS MTS-N para monitoração individual de fótons de corpo inteiro em H{sub P}(10)

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, M.S.; Silva, E.R. da; Maurício, C.L.P., E-mail: max.das.ferreira@gmail.com, E-mail: everton@ird.gov.br, E-mail: claudia@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The Institute of Radioprotection and Dosimetry (IRD/CNEN-RJ), uses an automatic thermoluminescent dosimetry (TL) system for evaluation of whole body for photons with individual monitors RADOS MTS-N, with TLF detector of LiF: Mg, Ti. The objective of this work was to characterize this system for the evaluation of H{sub P} (10) operating magnitude. The measuring range is 0.2 mSv to 2 Sv, for photon energies from 20 keV to 1250 keV. Performance tests were done for the following characteristics: homogeneity of the monitors, system reproducibility, linearity, temperature and humidity effect, energy and angular dependence and fading. The acceptance requirements used to test system performance have been drawn from national and international documents. The results obtained prove that the system can be used to measure the occupational dose of photons in H{sub P} (10)

  3. Thermoluminescence dating

    International Nuclear Information System (INIS)

    Price, D.M.

    1999-01-01

    Thermoluminescence (TL) dating of sediments depends upon the acquisition and long term stable storage of TL energy by crystalline minerals contained within a sedimentary unit. This energy is stored in the form of trapped electrons and quartz sand is the most commonly used mineral employed in the dating process. Prior to the final depositional episode it is necessary that any previously acquired TL is removed by exposure to sunlight. After burial the TL begins to build up again at a rate dependent upon the radiation flux delivered by long-lived isotopes of uranium, thorium and potassium. The presence of rubidium and cosmic radiation generally play a lesser but contributory roll, and the total radiation dose delivered to the TL phosphor is modified by the presence of water. The period since deposition is therefore measured by determining the total amount of stored TL energy, the palaeodose (P), and the rate at which this energy is acquired, the annual radiation dose (ARD). TL dating may be applied to eolian, fluvial, coastal and in some cases, marine sediments. the technique is also successfully applied to volcanic materials and to a certain extent to archeological specimens

  4. Thermoluminescence study of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Cu nanophosphor for gamma ray dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Mandlik, Nandkumar [Department of Physics, University of Pune, Ganeshkhind, Pune 411007 (India); Department of Physics, Fergusson College, Pune 411004 (India); Sahare, P.D. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Patil, B.J. [Department of Physics, University of Pune, Ganeshkhind, Pune 411007 (India); Department of Physics, Abasaheb Garware College, Pune 411004 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Ganeshkhind, Pune 411007 (India); Dhole, S.D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, University of Pune, Ganeshkhind, Pune 411007 (India)

    2013-11-15

    Nanocrystalline K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Cu was synthesized by chemical coprecipitation method and annealed at 700 °C. XRD of this sample shows the cubic structure and the crystallite size ∼20 nm. The same was also confirmed with TEM and shows the formation of nanorods of quite uniform in shape having diameter ∼20 nm and length in the range of 200 nm. The FTIR spectrum exhibits the bands corresponding to sulphate anions around 1015 and 600 cm{sup −1}. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. The glow curves of the pristine samples consists of two peaks one at around 139 °C while another one around 185 °C while the glow curve of samples annealed at 700 °C show a major peak at around 165 °C and other two peaks of low intensity at around 300 °C and 390 °C. The change in glow curve structures around 700 °C is due to the phase transition (from orthorhombic P2{sub 1}2{sub 1}2{sub 1}to cubic P2{sub 1}3 phase). The energy levels (trapping levels) get reorganized due to phase transition after the phase transition temperature (260 °C) and remain the same at higher temperatures (700 °C). TL dose response shows a linear behavior up to 1 kGy and further saturates with increase in the dose. Simple glow curve structure, easy method of synthesis, linear dose response and low fading make the nanocrystalline phosphor a good candidate for radiation dosimetry and especially, for the estimation of high doses of gamma rays where the microcrystalline phosphors generally saturate.

  5. Review of radiation dosimetry research at the University of Wisconsin during 1961-1982

    International Nuclear Information System (INIS)

    Cameron, J.R.; Moran, P.R.; Attix, F.H.

    1982-01-01

    The report provides a comprehensive review of the overall activities in this program since 1961. Research areas have included the development and use of lithium fluoride for thermoluminescent dosimetry, solid state neutron dosimetry, and ionization chamber research

  6. Performance tests on the NRPB thermoluminescent dosemeter

    CERN Document Server

    Shaw, K B

    1977-01-01

    Performance tests on the thermoluminescent dosemeter, designed at NRPB for use in the automated personal dosimetry system, are described. An ultra-thin lithium borate dosemeter has been developed for skin absorbed dose measurement. The X-ray, gamma-ray and beta-ray energy response of the dosemeter has been investigated and the angular response for the dosemeter has been examined. The annealing, read-out and stabilisation procedures for the dosemeter are described.

  7. Study of a new glass matrix by the thermoluminescence technique

    International Nuclear Information System (INIS)

    Ferreira, Pamela Z.; Vedovato, Uly P.; Cunha, Diego M. da; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P.; Carrera, Betzabel N.S.; Watanabe, Shigueo

    2015-01-01

    The thermoluminescence technique is widely used for both personal and for high-dose dosimetry. In this work, the thermoluminescence technique was utilized to study a new glass matrix, with nominal composition of 20Li 2 CO 3 .10Al 2 O 3 .20BaO.50B 2 O 3 (mol%), irradiated with different doses in a 60 Co source. The glow curves and the dose-response curve were obtained for radiation doses between 50 Gy and 900 Gy. The results showed that this new glass matrix presents potential use in high-dose dosimetry. (author)

  8. Thermoluminescence sensitivity variations in LiF PTFE dosemeters incurred by improper handling procedures

    CERN Document Server

    Mason, E W; MacKinlay, Alistair F; Saunders, D

    1975-01-01

    A systematic study of some anomalous darkening effects and thermoluminescence sensitivity variations observed in LiF:PTFE thermoluminescent dosemeters is described. Various likely causes of such effects have been investigated. The manufacturer's recommended cleaning procedures have been found to be inadequate and, in some cases, have been found to actually promote discolouration of the dosemeters. Recommendations are given for the successful use of LiF:PTFE thermoluminescent dosemeters in personal dosimetry.

  9. Numerical analysis of thermoluminescence glow curves; Analisis numerico de las cruvas de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Ros, J M; Delgado, A

    1989-07-01

    This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs.

  10. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlich, M; Soares, C G [National Bureau of Standards, Washington, DC (USA)

    1981-08-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams.

  11. Thermoluminescence properties of Yb-Tb-doped SiO2 optical fiber subject to 6 and 10 MV photon irradiation

    Science.gov (United States)

    Sahini, M. H.; Wagiran, H.; Hossain, I.; Saeed, M. A.; Ali, H.

    2014-08-01

    This paper reports thermoluminescence characteristics of thermoluminescence dosimetry 100 chips and Yb-Tb-doped optical fibers irradiated with 6 and 10 MV photons. Thermoluminescence response of both dosimeters increases over a wide photon dose range from 0.5 to 4 Gy. Yb-Tb-doped optical fibers demonstrate useful thermoluminescence properties and represent a good candidate for thermoluminescence dosimetry application with ionizing radiation. The results of this fiber have been compared with those of commercially available standard thermoluminescence dosimetry-100 media. Commercially available Yb-Tb-doped optical fibers and said standard media are found to yield a linear relationship between dose- and thermoluminescence signal, although Yb-Tb-doped optical fibers provide only 10 % of the sensitivity of thermoluminescence dosimetry-100. With better thermoluminescence characteristics such as small size (125 μm diameter), high flexibility, easy of handling and low cost, as compared to other thermoluminescence materials, indicate that commercial Yb-Tb-doped optical fiber is a promising thermoluminescence material for variety of applications.

  12. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  13. Personal radon daughter dosimetry

    International Nuclear Information System (INIS)

    Stocker, H.

    1979-12-01

    The conventional means of radon daughter exposure estimatikn for uranium miners in Canada is by grab sampling and time weighting. Personal dosimetry is a possible alternative method with its own advantages and limitations. The author poses basic questions with regard to two methods of radon daughter detection, thermoluminescent chips and track-etch film. An historical review of previous and current research and development programs in Canada and in other countries is presented, as are brief results and conclusions of each dosimeter evaluation

  14. Handbook of thermoluminescence

    CERN Document Server

    Furetta, Claudio

    2010-01-01

    This second edition of the Handbook of Thermoluminescence enlarges on all the subjects which were treated in the first edition and adds further arguments, including the theory of thermoluminescent dose measurement, several examples concerning the kinetics parameters determination using various methods such as peak shape, isothermal decay, and so on. A special section is devoted to food irradiation, an important subject at the present time, and to the thermoluminescent characterization of the minerals extracted from the irradiated food. Another new section is devoted to the thermoluminescent ph

  15. Study on the fast neutron sensitivity of thermoluminescent detectors

    International Nuclear Information System (INIS)

    Szabo, P.P.; Palfalvi, J.

    1984-03-01

    Fast neutron (14.7 MeV) sensitivity of several thermoluminescent detectors was determined. The investigated detectors were MTS-N type pellets (made in Poland) used routinely in the authors' institute for personnel dosimetry, 7 LiF powder used for accident dosimetry, CaSO 4 :Dy and CaSO 4 :Tm powders (made in Hungary) used for enviromental monitoring and space dosimetry. Both free-in-air and on-phantom irradiations were performed. The new results are compared with responses calculated and measured earlier. (author)

  16. Gamma-ray dosimetry measurements of the Little Boy replica

    International Nuclear Information System (INIS)

    Plassmann, E.A.; Pederson, R.A.

    1984-01-01

    We present the current status of our gamma-ray dosimetry results for the Little Boy replica. Both Geiger-Mueller and thermoluminescent detectors were used in the measurements. Future work is needed to test assumptions made in data analysis

  17. Thermoluminescence dosimetry of rare earth doped calcium ...

    Indian Academy of Sciences (India)

    Unknown

    Komath and their colleagues in the Bioceramics Division,. Sree Chitra Tirunal Institute for Medical Sciences and. Technology, Thiruvananthapuram, for providing laboratory facilities to carry out this work. The financial assistance provided by KSCSTE, Govt. of Kerala, for this work is gratefully acknowledged. References.

  18. Neutron dosimetry using thermoluminescent material and KBr

    International Nuclear Information System (INIS)

    Sahyun, A.

    1979-01-01

    It is investigated the misture of natural CaF 2 and KBr as thermal neutron dosimeter compared to pure fluorite. Firstly, it was found that a 50 - 50 mixture in weight produces the highest TL sensitivity when irradiated with thermal neutrons. Second, it was shown experimentally that for TL reading within 30 to 40 hours after irradiation, the radioisotopes 42 K, 80 Br and 80 sub(m)Br contribute predominantly, while for periods longer than 4 to 5 days, 82 Br also contributes significantly. It is in question, the minimum detectable fluence is of the order of 10 9 n/cm 2 . (Autor) [pt

  19. Thermoluminescence fast neutron dosimetry by laser heating

    International Nuclear Information System (INIS)

    Mathur, V.K.; Brown, M.D.; Braeunlich, P.

    1984-01-01

    Heating rates in excess of 10 4 K.sec -1 have been achieved for thin layers of TL dosemeters by laser heating. The high heating rate improves the signal to noise ratio up to a factor of 10 3 . Thus sensitive thin film fast neutron dosemeters with negligible self-shielding have become a practical reality. Thin samples of CaSO 4 :Dy have been investigated for their response to fast neutrons from a Pu-Be source and a 14.6 MeV neutron generator by using a hydrogenous radiator. A 15 watt CO 2 laser was focussed on the thin TLD layer to a spot size of less than 1 mm to heat it. An exposure of a few tens of milliseconds was sufficient to obtain a TLD curve, which was displayed and processed by a wave form digitiser. The laser spot could be scanned over the TLD sample by a x-y positioner and a large number of observations were obtained on each sample. Preliminary results show that it is possible to obtain a figure of merit of approx. 5% in a mixed n, γ field. A practical design for a fast neutron dosemeter is proposed. (author)

  20. The dosimetry thermoluminescent in civil aeronautics

    International Nuclear Information System (INIS)

    Azorin Nieto, J.; Guevara Polanco, J.C.; Garcia Villagomez, M.

    1998-01-01

    In Mexico we are carrying out a project to measure the ionizing radiation doses received by the crew members in civil airships as well as the environmental dose in the airships, with the purpose to determine if these doses surpass the cut-off one 0.11 mSv/h settled down by the IAEA for the publish in general and if therefore, these workers should be considered as occupational exposed works

  1. Personnel thermoluminescent dosimetry of plane pilots

    International Nuclear Information System (INIS)

    Azorin V, J.C.; Rivera M, T.; Azorin N, J.

    1999-01-01

    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)

  2. Thermoluminescent dosimeter system

    International Nuclear Information System (INIS)

    Felice, P.E.; Gonzalez, J.L.; Seidel, J.G.

    1979-01-01

    An improved thermoluminescent dosimeter system and apparatus for sensing alpha particle emission is described. A thermoluminescent body is sealed between a pair of metallized plastic films. The dosimeter is mounted within a protective inverted cup or a tube closed at one end, which is disposed in a test hole for exposure to radioactive radon gas which is indicaive of uranium deposits

  3. Thermoluminescence of novel MgO–CeO_2 obtained by a glycine-based solution combustion method

    International Nuclear Information System (INIS)

    Barrón, Victor Ramón Orante; Ochoa, Flor María Escobar; Vázquez, Catalina Cruz; Bernal, Rodolfo

    2016-01-01

    Thermoluminescence dosimetry properties of novel MgO–CeO_2 obtained by solution combustion synthesis in a glycine-nitrate process, are presented for the very first time. X-ray diffraction indicates the presence of cubic MgO and cerianite (CeO_2) for the annealed powder samples. Dosimetry features such as linear behaviour of the dose response without saturation in the dose interval studied, as well as asymptotic behaviour of the thermoluminescent signal fading place MgO–CeO_2 phosphor as a promising material for low-dose radiation dosimetry applications. - Highlights: • Thermoluminescence (TL) dosimetry properties of novel MgO–CeO_2 are presented. • TL glow curves display stable and dosimetric components. • Dose response showed a linear trend in the dose interval studied. • TL fading decay curve showed an asymptotic behaviour. • MgO–CeO_2 is suitable for personal, environmental and medical dosimetry.

  4. Advantages and disadvantages of luminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Olko, Pawel, E-mail: Pawel.Olko@ifj.edu.p [Institute of Nuclear Physics Polish Academy of Science (IFJ PAN), Krakow (Poland)

    2010-03-15

    Owing to their excellent dosimetric properties, luminescence detectors of ionizing radiation are now extensively applied in individual dosimetry services. The most frequently used personal dosemeters are based on Optically Stimulated Luminescence (OSL), radiophotoluminescence (RPL) or thermoluminescence (TL). Luminescence detectors have also found several applications in clinical dosimetry, especially around new radiation modalities in radiotherapy, such as Intensity Modulated Radiotherapy (IMRT) or ion beam radiotherapy. Requirements of luminescence detectors applied in individual and clinical dosimetry and some recent developments in luminescence of detectors and techniques leading to significant improvements of the functionality and accuracy of dosimetry systems are reviewed and discussed.

  5. Dosimetry; La dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Le Couteulx, I.; Apretna, D.; Beaugerie, M.F. [Electricite de France (EDF), 75 - Paris (France)] [and others

    2003-07-01

    Eight articles treat the dosimetry. Two articles evaluate the radiation doses in specific cases, dosimetry of patients in radiodiagnosis, three articles are devoted to detectors (neutrons and x and gamma radiations) and a computer code to build up the dosimetry of an accident due to an external exposure. (N.C.)

  6. Equipment for observing thermoluminescence

    International Nuclear Information System (INIS)

    Sette Camara, Alexandre; Cogneau, Michel; Ristori, Christian; Vargas, Jose Israel

    1971-06-01

    A detailed description is given of an apparatus for investigating thermoluminescence properties. Chopping of the emitted light and subsequent amplification of the electric signal derived led to high stability and sensitivity [fr

  7. Preparation of thermoluminescent materials

    International Nuclear Information System (INIS)

    1976-01-01

    Thermoluminescent materials have been found to be suitable for measuring long term exposures to low level ionizing radiation. Oxyhalides of lanthanum, gadolinium and yttrium, including the oxychlorides and oxybromides are activated with terbium and have been found to be most efficient oxygendominated phosphors having thermoradiant efficiencies with excitation by low level ionizing radiation. Thermoluminescence response increases when the previous materials have hafnium and zirconium additives

  8. 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)

  9. 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)

  10. Neutron dosimetry: problems, solutions, prospects and the role of trace detectors

    International Nuclear Information System (INIS)

    Fernandez, F.

    2009-10-01

    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)

  11. Laser readable thermoluminescent radiation dosimeters and methods for producing thereof

    International Nuclear Information System (INIS)

    Braunlich, P.F.; Tetzlaff, W.

    1989-01-01

    Thin layer thermoluminescent radiation dosimeters for use in laser readable dosimetry systems, and methods of fabricating such thin layer dosimeters are disclosed. The thin layer thermoluminescent radiation dosimeters include a thin substrate made from glass or other inorganic materials capable of withstanding high temperatures and high heating rates. A thin layer of a thermoluminescent phosphor material is heat bonded to the substrate using an inorganic binder such as glass. The dosimeters can be mounted in frames and cases for ease in handling. Methods of the invention include mixing a suitable phosphor composition and binder, both being in particulate or granular form. The mixture is then deposited onto a substrate such as by using mask printing techniques. The dosimeters are thereafter heated to fuse and bond the binder and phosphor to the substrate. 34 figs

  12. Thermoluminescence of Zn O thin films deposited by chemical bath

    International Nuclear Information System (INIS)

    Camacho A, M. C.; Cruz V, C.; Bernal H, R.; Berman M, D.; Castano M, V. M.

    2015-10-01

    Full text: Zn O films on Si were synthesized using a deposition method by chemical bath and thermally treated at 900 degrees C for 12 h in air. The morphological characterization by scanning electron microscopy reveals that uniform films were obtained. To investigate the thermoluminescent properties of the films were exposed to irradiation with beta particles with doses in the range from 0.5 to 128 Gy. The brightness curves obtained using a heating rate of 5 degrees C have two peaks, one at 124 and another at 270 degrees C, and a linear dependence of the integrated thermoluminescence as a function of dose. The second maximum reveals the existence of localized trapping states of potential utility in thermoluminescent dosimetry. (Author)

  13. Design and development of low cost thermoluminescence measurement system using PIC16F877 microcontroller

    International Nuclear Information System (INIS)

    Neelamegam, P; Rajendran, A

    2006-01-01

    A real time microcontroller based thermoluminescence system has been developed to measure light intensity and temperature and to control linear heating. This instruments permits to conduct investigations on thermoluminescent materials, such as alkali halides, phosphors and related compounds, which have important applications in materials science and in dosimetry. A low cost dedicated PIC16F877 based microcontroller board was employed for the hardware. The detail of its interface and software to measure thermoluminescence and to send data to PC is explained in this paper

  14. Design and development of low cost thermoluminescence measurement system using PIC16F877 microcontroller

    Energy Technology Data Exchange (ETDEWEB)

    Neelamegam, P [Department of Electronics and Instrumentation Engineering, Shunmuga Arts, Science, Technology and Research Academy (SASTRA), Deemed University, Thanjavur-613 402, Tamil Nadu (India); Rajendran, A [PG and Research Department of Applied Physics, Nehru Memorial College (Autonomous), Puthanampatti-621 007, Tiruchirappalli, Tamil Nadu (India)

    2006-05-15

    A real time microcontroller based thermoluminescence system has been developed to measure light intensity and temperature and to control linear heating. This instruments permits to conduct investigations on thermoluminescent materials, such as alkali halides, phosphors and related compounds, which have important applications in materials science and in dosimetry. A low cost dedicated PIC16F877 based microcontroller board was employed for the hardware. The detail of its interface and software to measure thermoluminescence and to send data to PC is explained in this paper.

  15. Preparation of lithium fluoride for thermoluminescent detectors of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mironenko, S.N.; Nepomnyashchikh, A.I.; Ikrami, D.D.; Paramzin, A.S.; Rakhimov, M.Eh.

    1985-03-01

    The thermostimulated luminescence (TSL) of lithium fluoride monocrystals depending on the method of preparation of starting raw material and features of its preliminary processing is investigated. It is shown that only lithium fluoride of high purity prepared through the stage of formation of hydrofluoride and its subsequent decomposition can be used without any additional processing for manufacturing monocrystal detectors of thermoluminescent dosimetry of the ionizing radiation with low intensity of low temperature peaks.

  16. 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)

  17. NRPB patient dosimetry service

    International Nuclear Information System (INIS)

    Shrimpton, P.; Hillier, M.; Bungay, D.; Wall, B.

    1994-01-01

    For nearly 20 years, thermoluminescent dosemeters (TLDs) have been used by NRPB to investigate the doses received by patients undergoing diagnostic examinations with x-rays, and these measurements have formed the basis for national recommendations on patient protection. Monitoring typical levels of patient dose should represent an essential element of routine quality assurance in x-ray departments. In order to promote more widespread measurements in hospitals, NRPB has drawn on a wealth of experience to establish a high-quality service providing TLDs for medical dosimetry by post. (author)

  18. Fast neutron dosimetry

    International Nuclear Information System (INIS)

    DeLuca, P.M. Jr.; Pearson, D.W.

    1992-01-01

    This progress report concentrates on two major areas of dosimetry research: measurement of fast neutron kerma factors for several elements for monochromatic and white spectrum neutron fields and determination of the response of thermoluminescent phosphors to various ultra-soft X-ray energies and beta-rays. Dr. Zhixin Zhou from the Shanghai Institute of Radiation Medicine, People's Republic of China brought with him special expertise in the fabrication and use of ultra-thin TLD materials. Such materials are not available in the USA. The rather unique properties of these materials were investigated during this grant period

  19. Thermoluminescence dating method

    International Nuclear Information System (INIS)

    Zink, A.

    2004-01-01

    A crystal that is submitted to radiation stores energy and releases this energy under the form of light whenever it is heated. These 2 properties: the ability to store energy and the ability to reset the energy stored are the pillars on which time dating methods like thermoluminescence are based. A typical accuracy of the thermoluminescence method is between 5 to 7% but an accuracy of 3% can be reached with a sufficient number of measurement. This article describes the application of thermoluminescence to the dating of a series of old terra-cotta statues. This time measurement is absolute and does not require any calibration, it represents the time elapsed since the last heating of the artifact. (A.C.)

  20. Thermoluminescence dating of pottery

    International Nuclear Information System (INIS)

    Higashimura, Takenobu; Ichikawa, Yoneta.

    1978-01-01

    This report is divided into two parts. The first half describes on the history of thermoluminescence dating, and the latter half, the principle and measurement examples. It was in late 1955 that the measurement of radiation dose using thermoluminescence began. The method to thermoluminescence dating was developed when it was found that most natural stones emit the thermoluminescence. About Greek earthen wares, the study of which was presented in 1961 by G. Kennedy of University of California, the dating was able to be made within the standard deviation of 10%. Since then, this dating method progressed rapidly, and a number of laboratories are now forwarding the investigation. In the samples of natural materials, intensity of thermoluminescence I is proportional to natural radiation dose D which has been absorbed by the samples, i.e. I = kD, where k is the susceptibility of thermoluminescence of the samples. Since k is different in each sample, D can be determined by irradiating the sample with β or γ ray of known dose D 0 , measuring its luminescence I 0 , and eliminating k through these two equations, because i 0 = kD 0 . Next, if t is assumed to be the time passed since a pottery was made, D is expressed as Rt, where R is the natural radiation dose per year absorbed by the pottery. Thus t is determined if R is known. The report describes on the method of measuring R. As an example, the results of measurement of the potteries excavated at Iwakura remains, Yorikura, Taishaku-kyo, are listed. Results by 14 C dating are also described for reference. (Wakatsuki, Y.)

  1. Accidental and retrospective dosimetry using TL method

    International Nuclear Information System (INIS)

    Mesterházy, D.; Osvay, M.; Kovács, A.; Kelemen, A.

    2012-01-01

    Retrospective dosimetry is one of the most important tools of accidental dosimetry for dose estimation when dose measurement was not planned. In the affected area many objects can be applied as natural dosimeters. The paper discusses our recent investigations on various electronic components and common salt (NaCl) having useful thermoluminescence (TL) properties. Among materials investigated the electronic components of cell phones seem promising for retrospective dosimetry purposes, having high TL responses, proper glow curve peaks and the intensity of TL peaks vs. gamma dose received provided nearly linear response in the dose range of 10 mGy–1.5 Gy. - Highlights: ► Electronic components and common salt were investigated for accidental and retrospective dosimetry. ► SMD resistors seem promising for retrospective dosimetry purposes. ► Table salt can be used effectively for accidental dosimetry purposes, as well.

  2. Thermoluminescence from natural calcites

    International Nuclear Information System (INIS)

    Calderon, T.; Jaque, F.; Coy-yll, R.

    1984-01-01

    Thermoluminescence (TL) as well as absorption and EPR spectra of x-irradiated natural calcites have been obtained. Irradiation produces UV absorption bands and a decrease of the Mn 2+ EPR spectrum. A correlation of each TL peak with the bleaching steps of UV absorption bands and the recovering in intensity of the Mn 2+ EPR spectrum has been found. These experimental results support a new model for the radiation damage and thermoluminescence process in calcites. The main point in this model is that holes become trapped at impurities, and the electrons are trapped at dislocations in the form of CO 3 3- . (author)

  3. Thermoluminescence of strontium tetraborate

    International Nuclear Information System (INIS)

    Santiago, M.; Caselli, E.; Lester, M.

    1999-01-01

    The thermoluminescent properties of crystalline strontium tetraborate are reported. Without activators it has an efficiency comparable to that of TLD-700 powder. Its fading after 40 days amount to less than 2%. The isometric plot shows that most of the emitted light is concentrated at wavelengths ranging from 350 to 450 nm, which accounts partially for the high efficiency. (author)

  4. Introduction to radiological physics and radiation dosimetry

    CERN Document Server

    Attix, Frank Herbert

    2004-01-01

    A straightforward presentation of the broad concepts underlying radiological physics and radiation dosimetry for the graduate-level student. Covers photon and neutron attenuation, radiation and charged particle equilibrium, interactions of photons and charged particles with matter, radiotherapy dosimetry, as well as photographic, calorimetric, chemical, and thermoluminescence dosimetry. Includes many new derivations, such as Kramers X-ray spectrum, as well as topics that have not been thoroughly analyzed in other texts, such as broad-beam attenuation and geometrics, and the reciprocity theorem

  5. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    International Nuclear Information System (INIS)

    Ehrlich, M.; Soares, C.G.

    1981-01-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams. (author)

  6. Study of a new dosimetric radio-thermoluminescent systems

    International Nuclear Information System (INIS)

    Cazac, T.C.

    1980-01-01

    This is the first Romanian study to investigate conditions to obtain the radio-thermo-luminescent systems: MgB 4 O 7 :A(A-Nd,Sm,Eu,Dy,Tb,Dy+Sm and Tb+Sm) MgF 2 A (A=Mn,Dy,Tb,Sm,Li), their essential dosimetric characters, as well as the (MgF 2 =Mn) thermophosphorus mixture with a ( 6 LiF) lithium target. An investigation was developed upon a new category of radio-thermoluminescent detectors with low radiation energy dependence and fading, magnesjum boride activated by several elements of the lanthanides class (Nd,Sm,Eu,Dy,Tb). A new radio-thermoluminescent dosimetric system with high sensitivity and moderate dependence on energy radiation - (Mnsup(2+)) manganese activated magnesium fluoride - was also studied. The author explored application of investigated detectors MgF 2 =Mn, MgB 4 O 7 =Dy and MgB 4 O 7 :Tb in neutron dosimetry in complex gamma-neutron fields. It is deemed that by using the dosimetric systems reported in the thesis in order to measure gamma, beta and neutron radiation doses, dosimetric control can be ensured both in professional dosimetry and in nuclear accident dosimetry, as well as in various basic and applicative investigations. A modest contribution is thus made towards achieving the national nuclear program through an extension of the thermophosphorus range with practical applications in nuclear radiation dosimetry. (author)

  7. Thermoluminescence of magnesium doped zirconium oxide (ZrO2:Mg) UV irradiated

    International Nuclear Information System (INIS)

    Rivera Montalvo, Teodoro; Furetta, Claudio

    2008-01-01

    Full text: The monitoring of ultraviolet radiation (UVR) different thermoluminescent (TL) materials have been used to measure UVR. UV dosimetry using thermoluminescence phenomena has been suggested in the past by several authors. This technique has an advantage over others methods due to the readout of the samples. Other advantages of these phosphors are their small size, portability, lack of any power requirements, linear response to increasing radiation dose and high sensitivity. Zirconium oxide, recently received full attention in view of their possible use as thermoluminescent dosimeter (TLD), if doped with suitable activators, in radiation dosimetry. In the present investigation thermoluminescent (TL) properties of magnesium doped zirconium oxide (ZrO 2 :Mg) under ultraviolet radiation (UVR) were studied. The ZrO 2 :Mg powder of size 30-40 nm, having mono clinical structure, exhibit a thermoluminescent glow curve with one peak centered at 180 C degrees. The TL response of ZrO 2 :Mg as a function ultraviolet radiation exhibits four maxima centered at 230, 260, 310 and 350 nmn. TL response of ZrO 2 :Mg as a function of spectral irradiance of UV Light was linear in a wide range. Fading and reusability of the phosphor were also studied. The results showed that ZrO 2 :Mg nano powder has the potential to be used as a UV dosemeter in UVR dosimetry. (author)

  8. Characterization of the personal thermoluminescent dosemeter of LiF: Mg, Ti + Ptfe

    International Nuclear Information System (INIS)

    Azorin N, J.; Gutierrez C, A.; Gonzalez M, P.

    1991-01-01

    The objective of this work is to characterize the thermoluminescent dosemeters taken place in the laboratory in form of pellets of LiF: Mg, Ti + Ptfe like personal dosemeters, subjecting them to the operation tests proposed by the international standards and comparing them with the TLD-100, the Tl dosemeter more used at the moment for personal dosimetry

  9. Thermally stimulated conductivity and thermoluminescence from Al2O3 : C

    DEFF Research Database (Denmark)

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

    1999-01-01

    Simultaneous measurements of thermoluminescence (TL) and thermally stimulated conductivity (TSC) are reported on single-crystal dosimetry-quality Al2O3:C following gamma irradiation at room temperature. Analysis of the data reveals a superposition of several first-order TL and TSC peaks caused...

  10. Preparation and structural characterization of the thermoluminescent material CaSO4: Dy

    International Nuclear Information System (INIS)

    Sanchez R, A.; Azorin, J.; Gonzalez M, P.R.; Rivera, T.

    2005-01-01

    The grade of crystallinity of a material is important so that the one is presented the thermoluminescence phenomenon; for what is necessary to study those structural characteristic of a TL material and to correlate them with its TL response when being irradiated with ionizing radiation. The calcium sulfate activated with Dysprosium (CaSO 4 : Dy) it is a material that has demonstrated its efficiency in the dosimetry of the ionizing radiation for the thermoluminescence method. In this work the structural characterization of this prepared material for the recrystallization method by means of the evaporation of the solvent and their relationship with their TL response is presented. The results showed that the best material to be used in thermoluminescent dosimetry presents a crystalline structure in orthorhombic phase and a particle size in the interval of 80 μm to 200 μm. (Author)

  11. Thermoluminescent dosimetric properties of Descalvado sand

    International Nuclear Information System (INIS)

    Teixeira, M.I.; Caldas, L.V.E.

    2006-01-01

    Sand samples proceeding from Descalvado, Sao Paulo, were studied with regard to their dosimetric properties using the thermoluminescence technique (TL) for high doses. These sand samples present steady physical and chemical characteristics to the end items, and they are used in the glass industry and for casting. The TL curves of the samples were obtained after an irradiation at the Gamma-Cell system ( 60 Co), of IPEN. The glow curves present two peaks at 80 C and 220 C approximately. Calibration curves were obtained for doses between 50 Gy and 5 kGy. The results indicate that the sand samples can be used for high-doses dosimetry in several areas of applications of ionizing radiation. (Author)

  12. Thermoluminescent dosimetric properties of Descalvado sand

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, M.I.; Caldas, L.V.E

    2006-07-01

    Sand samples proceeding from Descalvado, Sao Paulo, were studied with regard to their dosimetric properties using the thermoluminescence technique (TL) for high doses. These sand samples present steady physical and chemical characteristics to the end items, and they are used in the glass industry and for casting. The TL curves of the samples were obtained after an irradiation at the Gamma-Cell system ({sup 60} Co), of IPEN. The glow curves present two peaks at 80 C and 220 C approximately. Calibration curves were obtained for doses between 50 Gy and 5 kGy. The results indicate that the sand samples can be used for high-doses dosimetry in several areas of applications of ionizing radiation. (Author)

  13. Thermoluminescence studies in geology

    International Nuclear Information System (INIS)

    Sankaran, A.V.; Sunta, C.M.; Nambi, K.S.V.; Bapat, V.N.

    1980-01-01

    Even though the phenomenon of thermoluminescence is well studied, particularly over last 3 decades, its potentialities in the field of geology have not been adequately evaluated. In this report several useful applications of TL in mineralogy, petrogenesis, stratigraphy, tectonics, ore-prospecting and other branches have been identified with particular emphasis to the Indian scene. Important areas in the country that may provide the basic material for such studies are indicated at the end along with brief geological or mineralogical accounts. (auth.)

  14. Thermoluminescence spectra of amethyst

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Q. [Suzhou Railway Teachers College (China). Dept. of Physics; Yang, B. [Beijing Normal University (China). Dept. of Physics; Wood, R.A.; White, D.R.R.; Townsend, P.D.; Luff, B.J. [Sussex Univ., Brighton (United Kingdom). School of Mathematical and Physical Sciences

    1994-04-01

    Thermoluminescence and cathodoluminescence data from natural and synthetic amethyst and synthetic quartz samples are compared. The spectra include features from the quartz host lattice and from impurity-generated recombination sites. Emission features exist throughout the wavelength range studied, 250-800 nm. The near infrared emission at 740-750 nm appears to be characteristic of the amethyst and is proposed to be due to Fe ion impurity. (Author).

  15. Research and innovation in radiation dosimetry

    International Nuclear Information System (INIS)

    Delgado, A.

    1999-01-01

    In this article some relevant lines of research in radiation dosimetry are presented. In some of them innovative approaches have been recently proposed in recent years. In others innovation is still to come as it is necessary in view of the insufficiency of the actual methods and techniques. mention is made to Thermoluminescence Dosimetry an to the improvement produced by new computational methods for the analysis of the usually complex TL signals. A solid state dosimetric technique recently proposed, Optically Stimulated Luminescence, OSL, is briefly presented. This technique promises advantages over TLD for personal and environmental dosimetry. The necessity of improving the measurement characteristics of neutron personal dosemeters is commented, making reference to some very recent developments. The situation of the dosimetry in connection with radiobiology research is overviewed, commenting the controversy on the adequacy and utility of the quality absorbed dose for these activities. Finally the special problematic of internal dosimetry is discussed. (Author) 25 refs

  16. Thermoluminescence - physics and applications

    International Nuclear Information System (INIS)

    Sunta, C.M.

    1992-01-01

    The interaction of ionizing radiations with matter leads to various effects, some of which leave memory in the target material. These memory effects can be seen as the after-effects of the irradiation. Thermoluminescence is one such phenomenon in the insulating solids. This paper describes the sequence of the physical events beginning with the incidence of an ionizing particle, leading to a trail of atomic and electronic displacements which stabilize in the form of so called defect centres. These defects - interstitials, colour centres, etc., store energy in their configuration. Most of the damage effects are reversible. The return of the displaced entities to their original site leads to the release of the stored energy. Thermoluminescence is the result of the re-adjustment (relaxation) of the displaced electrons. The stimulation for the relaxation process is provided by heating of the irradiated sample. The kinetics of the thermoluminescence process has been explained phenomenologically. The correspondence between the defect centres and the TL glow peaks has remained vague or ambiguous even in the most widely studied TL materials. Notwithstanding this deficiency, the phenomenon has found many practical applications. The paper deals mainly with the physical processes involved in the TL emission and alludes briefly to its involvement in applied areas.(author). 6 refs., 2 figs

  17. Evaluation of the thermoluminescent detector answers of CaSO{sub 4}:Dy, LiF:Mg,Ti and micro LiF:Mg,Ti in photon clinical beams dosimetry using water simulator; Avaliacao da resposta de detectores termoluminescentes de CaSO4:Dy, LiF:Mg,Ti e microLiF:Mg,Ti na dosimetria de feixes clinicos de fotons utilizando simulador de agua

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, Luciana C.; Veneziani, Glauco R.; Campos, Leticia L., E-mail: lmatsushima@usp.b, E-mail: veneziani@ipen.b, E-mail: lcrodri@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (GMR/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Gerencia de Metrologia das Radiacoes; Sakuraba, Roberto K.; Cruz, Jose C. da, E-mail: rsakuraba@einstein.b, E-mail: jccruz@einstein.b [Sociedade Beneficente Israelita Brasileira, Sao Paulo, SP (Brazil). Hospital Albert Einstein (HAE)

    2011-10-26

    This paper perform the comparative study of thermoluminescent answer of calcium sulfate dosemeter doped with dysprosium (DaSO{sub 4}:Dy) produced by the IPEN, Sao Paulo, with answer of lithium fluoride dosemeters doped with magnesium and titanium (LiF:Mg, Ti) in the dosimetry of clinical beams of photons (6 and 15 MV) by using water simulator object. Dose-answer curves were obtained for gamma radiation of cobalt-60 in the air and in conditions of electronic equilibrium (plate of PMMA), and clinical photons of CLINAC model 2100C accelerators of the two evaluated hospitals: Hospital das Clinicas of the Faculty of Medicine of Sao Paulo university and Hospital Albert Einstein. It was also evaluated the sensitivity and reproduction of the three dosemeters

  18. 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)

  19. 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)

  20. Thermoluminescence: its understanding and applications

    International Nuclear Information System (INIS)

    Nambi, K.S.V.

    1977-01-01

    The phenomenon of thermoluminescence is treated exhaustively both mathematically and physically. All the possible applications of the phenomenon are briefly described and an optimistic picture of the future trends in this field is projected. A review of latest information on thermoluminescence instrumentation and phosphors is also included [pt

  1. Dosimetry in dentistry.

    Science.gov (United States)

    Asha, M L; Chatterjee, Ingita; Patil, Preeti; Naveen, S

    2015-01-01

    The purpose of this paper was to review various dosimeters used in dentistry and the cumulative results of various studies done with various dosimeters. Several relevant PubMed indexed articles from 1999 to 2013 were electronically searched by typing "dosimeters", "dosimeters in dentistry", "properties of dosimeters", "thermoluminescent and optically stimulated dosimeters", "recent advancements in dosimetry in dentistry." The searches were limited to articles in English to prepare a concise review on dental dosimetry. Titles and abstracts were screened, and articles that fulfilled the criteria of use of dosimeters in dental applications were selected for a full-text reading. Article was divided into four groups: (1) Biological effects of radiation, (2) properties of dosimeters, (3) types of dosimeters and (4) results of various studies using different dosimeters. The present review on dosimetry based on various studies done with dosimeters revealed that, with the advent of radiographic technique the effective dose delivered is low. Therefore, selection of radiological technique plays an important role in dental dose delivery.

  2. Thermoluminescence dating. Application to the chronology of volcanic ashes

    International Nuclear Information System (INIS)

    Pilleyre, T.

    1991-09-01

    Thermoluminescent (TL) dating is generally used for minerals heated in the past and can be used for absolute chronology of volcanic ashes but seems limited to less than 15.000 years. The aim of the thesis is the study of thermoluminescent properties of quartz for high doses and long irradiations using the red TL peak of quartz which is situated at high temperature (about 370 deg. C) to extend the method for higher ages. A theory, based on spatial correlation between electron and hole created during the same ionization, is developed. A chapter is devoted to dosimetry because of its importance in TL dating, especially alpha scintillation counting and the influence of humidity on the determination of annual dose. Volcanic samples are dated from 10.000 to 80.000 years before present

  3. Study on carbonated hydroxyapatite as a thermoluminescence dosimeter

    International Nuclear Information System (INIS)

    Shafaei, M.; Sardari, D.; Ziaie, F.; Larijani, M.M.

    2015-01-01

    In this study, carbonated hydroxyapatite nanoparticles were used for thermoluminescence dosimetry. The nano-structure carbonated hydroxyapatite synthesized via hydrolysis of CaHPO 4 and CaCO 3 . The obtained nano powders were characterized by XRD technique and FTIR spectroscopy system. The carbonated hydroxyapatite samples were irradiated at different doses using 60 Co gamma rays, and were subjected to thermoluminescence measurement system, consequently. The TL glow curve exhibited two distinguishable peaks centered at around of 165 C and 310 C. The TL response of carbonated hydroxyapatite samples as a function of absorbed dose was linear in the range of 25-1000 Gy. Other dosimetric features of the carbonated hydroxyapatite nanoparticles including fading and reproducibility were also investigated.

  4. Thermoluminescent dosemeter in a X-ray diffractometer

    International Nuclear Information System (INIS)

    Mendoza A, D.; Gonzalez M, P.; Falcon B, T.; Castano, V.M.

    1999-01-01

    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)

  5. Thermoluminescence of sulfated zircon exposed to gamma radiation

    International Nuclear Information System (INIS)

    Rubio, E.; Castano, V.M.; Mendoza A, E.; Gonzalez, P.R.

    2003-01-01

    In this work, the thermoluminescent (Tl) signal induced by gamma radiation in zirconia and sulfated zirconia samples embedded in Ptfe pellets is reported and discussed. In this case, samples were obtained through sol-gel method using zirconium n-propoxide and H 2 SO 4 as precursors, and later were subjected to thermal treatment at 600 C to obtain, the tetragonal phase accordingly to X-ray diffraction analysis. Experimental results show that the thermoluminescent glow peak depends on both, the crystalline structure and sulfate concentration. Two maximum peaks were observed located at 147 C and 274 C arising from the electronic transitions. Tl response as a function of the absorbed dose shows a linear increase for a wide of range exposure as well as good stability in time. The high sensitivity, dose linearity and signal stability of this material open the potential possibility to be used for the dosimetry applications. (Author)

  6. Thermoluminescence of pyramid stones

    International Nuclear Information System (INIS)

    Gomaa, M.A.; Eid, A.M.

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310 0 C, respectively. The TL glow peaks of samples annealed at 600 0 C, then exposed to 60 Co γ-rays were observed at 120, 190 and 310 0 C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year. (author)

  7. Thermoluminescence of pyramid stones

    Energy Technology Data Exchange (ETDEWEB)

    Gomaa, M A; Eid, A M [Atomic Energy Establishment, Cairo (Egypt)

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310/sup 0/C, respectively. The TL glow peaks of samples annealed at 600/sup 0/C, then exposed to /sup 60/Co ..gamma..-rays were observed at 120, 190 and 310/sup 0/C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year.

  8. Entrance surface dose measurements in mammography using thermoluminescence technique

    International Nuclear Information System (INIS)

    Rivera, T.; Vega C, H.R.; Manzanares A, E; Azorin, J.; Gonzalez, P.R.

    2007-01-01

    Full text: Of the various techniques that can be used for personnel dosimetry, thermoluminescence dosimetry (TLD) has emerged as a superior technique due to its manifold advantages over other methods of dose estimation. Various phosphors have been therefore investigated regarding their suitability for dosimetry. In this paper, a dosimetry system based on thermally stimulated luminescence (TSL) from zirconium oxide phosphors embedded in polytetrafluorethylene (ZrO 2 +PTFE) was developed for entrance surface doses (ES) measurements in mammography. Small ZrO 2 pellets of 5 mm in diameter and 0.8 mm in thickness were used. The reproducibility of measurements and linearity of ZrO 2 were also studied. The results were compared with those obtained from LiF:Mg,Cu,P usually used for the determination of absorbed dose in mammography. Measurements both per unit air kerma and In vivo were performed using a mammography unit model DMR (General Electric). The results showed that ZrO 2 TLDs can be used for the same X-ray dosimetry applications as LiF:Mg,Cu,P, with each type having the disadvantage of a response dependent on energy, particularly at low energies. These results indicate a considerable potential for use in routine control and In vivo ES measurements in mammography. (Author)

  9. The personnel dosimetry record keeping system at AEE Winfrith

    International Nuclear Information System (INIS)

    Gill, D.W.

    1979-09-01

    Since May 1978 the exposure of personnel to external radiation has been assessed by Thermoluminescent Dosimetry, (TLD). The dosemeter consists of a TLD card similar to that used by the National Radiological Protection Board, held in a plastic badge designed at AEE Winfrith, and used in conjunction with a D A Pitman Ltd Type 605 Automatic Reader. The report describes the dosemeter, the operation of the dosimetry service and the system for maintaining a computerised record keeping system. (author)

  10. Thermoluminescent characteristics of ZrO2:Nd films

    International Nuclear Information System (INIS)

    Vera B, G.; Rivera M, T.; Azorin N, J.; Falcony G, C.; Garcia H, M.; Martinez S, E.

    2002-01-01

    In this work it is exposed the obtained results after analysing the photo luminescent and thermoluminescent characteristics of activated zirconium oxide with neodymium (ZrO 2 :Nd) and its possible application in the UV radiation dosimetry. The realized experiments had as objective to study the characteristics such as the optimum thermal erased treatment, the influence of light on the response, the response depending on the wavelength, the fadeout of the information, the temperature effect, the response depending on the time and the recurring of the response. The results show that the ZrO 2 :Nd is a promising material to be used as Tl dosemeter for the UV radiation. (Author)

  11. Thermoluminescent system for low temperatures

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da; Caldas, L.V.E.; Leite, N.G.

    1988-09-01

    A system for measurements of the thermoluminescent glow curve, the thermoluminescent emission spectrum and the optical absorption spectrum of solid samples, from liquid nitrogen temperature up to 473 K, is reported. A specially designed temperature programmer provides a linear heating of the sample at a wide range of selectable heating rates, as also long term steady-state temperatures for annealing and isothermal decay studies. The system operates at a pressure of 1.33 x 10 -3 Pa. Presently it is being used for lithium fluoride low temperature thermoluminescent studies. (author) [pt

  12. Evaluation of new and conventional thermoluminescent phosphors for environmental monitoring using automated thermoluminescent dosimeter readers

    International Nuclear Information System (INIS)

    Rathbone, B.A.; Endres, A.W.; Antonio, E.J.

    1994-10-01

    In recent years, there has been considerable interest in a new generation of super-sensitive thermoluminescent (TL) phosphors for potential use in routine personnel and environmental monitoring. Two of these phosphors, α-Al 2 O 3 :C and LiF:Mg,Cu,P, are evaluated in this paper for selected characteristics relevant to environmental monitoring, along with two conventional phosphors widely used in environmental monitoring, LiF:Mg,Ti and CaF 2 :Dy. The characteristics evaluated are light-induced fading, light-induced background, linearity and variability at low dose, and the minimum measurable dose. These characteristics were determined using an automated commercial dosimetry system (Harshaw System 8800) and routine processing protocols. Annealing and readout protocols for each phosphor were optimized for use in a large-scale environmental monitoring program

  13. Determination of the dose rapidity of a 90 Sr beta radiation source using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.; Azorin N, J.; Rivera M, T.

    2000-01-01

    The thermoluminescent dosemeters developed in Mexico, have been used efficiently in environmental and personal dosimetry. When the dose rate of some source is not known can be estimated with the use of thermoluminescent dosemeters taking in account the geometrical array used in the irradiations for reproducibility of the results in posterior irradiations. In this work it was estimated the dose rate of a 90 Sr- 90 Y beta radiation source which is property of the Nuclear Sciences Institute, UNAM, therefore it was l ended to the Metropolitan Autonomous University- Iztapalapa Unit for the characterization of new Tl materials, taking account of the institutional collaboration agreements. (Author)

  14. The RERF dosimetry measurements database

    International Nuclear Information System (INIS)

    Cullings, Harry M.; Fujita, Shoichiro; Preston, Dale L.; Grant, Eric J.; Shizuma, Kiyoshi; Hoshi, Masaharu; Maruyama, Takashi; Lowder, Wayne M.

    2005-01-01

    The Radiation Effects Research Foundation maintains a database containing detailed information on every known measurement of environmental materials in the cities of Hiroshima and Nagasaki for gamma-ray thermoluminescence or neutron activation produced by incident radiation from the atomic bomb detonations. The intent was to create a single information resource that would consistently document, as completely as possible in each case, a standard array of data for every known measurement. This database provides a uniquely comprehensive and carefully designed reference for the dosimetry reassessment. (J.P.N.)

  15. Gamma dosimetry of high doses

    International Nuclear Information System (INIS)

    Martinez C, T.; Galvan G, A.; Canizal, G.

    1991-01-01

    The gamma dosimetry of high doses is problematic in almost all the classic dosemeters either based on the thermoluminescence, electric, chemical properties, etc., because they are saturated to very high dose and they are no longer useful. This work carries out an investigation in the interval of high doses. The solid system of heptahydrate ferrous sulfate, can be used as solid dosemeter of routine for high doses of radiation. The proposed method is simple, cheap and it doesn't require sophisticated spectrophotometers or spectrometers but expensive and not common in some laboratories

  16. 5th symposium on neutron dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Spurny, F

    1985-03-01

    The symposium was held in Neuherberg near Munich on September 17-20, 1984 and was attended by 200 specialists from 20 coutries. The participants discussed the following areas of neutron dosimetry: basic concept and analysis of irradiation, basic data, proportional counters in radiation protection, detector response and spectrometry, enviromental monitoring, radiobiology and biophysical models, analysis of neutron fields, thermoluminescent detectors, personnel monitoring, calibration, measurement in the environment of /sup 252/Cf sources, analysis of fields and detector response, standardization dosimetry, ionization chambers, planning of therapeutical irradiation study of depth dose distribution, facilities for neutron therapy and international comparison. (E.S.).

  17. 5th symposium on neutron dosimetry

    International Nuclear Information System (INIS)

    Spurny, F.

    1985-01-01

    The symposium was held in Neuherberg near Munich on September 17-20, 1984 and was attended by 200 specialists from 20 coutries. The participants discussed the following areas of neutron dosimetry: basic concept and analysis of irradiation, basic data, proportional counters in radiation protection, detector response and spectrometry, enviromental monitoring, radiobiology and biophysical models, analysis of neutron fields, thermoluminescent detectors, personnel monitoring, calibration, measurement in the environment of 252 Cf sources, analysis of fields and detector response, standardization dosimetry, ionization chambers, planning of therapeutical irradiation study of depth dose distribution, facilities for neutron therapy and international comparison. (E.S.)

  18. Dosimetry Service

    CERN Multimedia

    2006-01-01

    Cern Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry Dosimetry Service is open every morning from 8.30 - 12.00. Closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after the use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel. 7 2155 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  19. Thermoluminescence of irradiated foods

    International Nuclear Information System (INIS)

    Wagner, U.; Helle, N.; Boegl, K.W.; Schreiber, G.A.

    1993-01-01

    This report describes developments and applications of the thermoluminescence (TL) analysis of mineral contaminants in foods. Procedures are presented to obtain minerals from most different products such as pepper, mangos, shrimps and mussels. The effect of light exposure during the storage of foods on the TL intensity of minerals is examined and corresponding conclusions for routine control are drawn. It is also shown that the normalization of TL intensities - the essential step to identify irradiated samples - can not only be achieved by γ, X or β rays but also by UV radiation. The results allow the conclusion that a clear identification of any food which has been irradiated with more than 1 kGy is possible if enough minerals can be isolated. (orig.)

  20. Mexican gems as thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Azorin N, J.

    1979-01-01

    The possibility of using naturally ocurring mexican gems as thermoluminescent dosimeters (TLD) was investigated. Twelve types of gems were irradiated with X and gamma rays in order to determinate their dosimetric properties. Three of these gems showed favorable thermoluminescent characteristics compared with commercial thermoluminescent dosimeters. The plots of their thermoluminescent response as a function of gamma dose are straight lines on full log paper in the dose range 10 -2 to 10 2 Gy. The energy dependence is very strong to low energies of the radiation. Their fading was found to be about 5%/yr. and they may be annealed as reused without loss in sensitivity. Therefore, these gems can be used as X and gamma radiation dosimeters. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Shirlane Barbosa de

    2017-07-01

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

  2. The reliability of the systems of personal dosimetry

    International Nuclear Information System (INIS)

    Gullberg, O.; Lindborg, L.

    1982-01-01

    The dosimeters of companies and institutions have been irradiated at various energy and dose equivalent levels. Systematic and coincident errors in measurement are presented. The results show that relatively large systematic errors can be made by both the thermoluminescent and film systems. Various techniques to judging the quality of the dosimetry are discussed. (G.B.)

  3. Protocols for Thermoluminescence and Optically Stimulated Luminescence Research at DOSAR

    International Nuclear Information System (INIS)

    Bernal, SM

    2004-01-01

    The Life Sciences Division (LSD) of Oak Ridge National Laboratory (ORNL) has a long record of radiation dosimetry research at the Dosimetry Applications Research (DOSAR) facility complex. These facilities have been used by a broad segment of the research community to perform a variety of experiments in areas including, but not limited to, radiobiology, radiation dosimeter and instrumentation development and calibration, and materials testing in a variety of radiation environments. Collaborations with the University of Tennessee-Knoxville (UTK) have also led to important contributions in the area of archaeometry, particularly as it relates to the use of radiation dosimetry to date archaeological artifacts. This manual is to serve as the primary instruction and operation manual for dosimetric and archaeometric research at DOSAR involving thermoluminescence (TL) and optically stimulated luminescence (OSL). Its purpose is to (1) provide protocols for common practices associated with the research, (2) outline the relevant organizational structure, (3) identify the Quality Assurance plan, and (4) describe all the procedures, operations, and responsibilities for safe and proper operation of associated equipment. Each person who performs research at DOSAR using TL/OSL equipment is required to read the latest revision of this manual and be familiar with its contents, and to sign and date the manual's master copy indicating that the manual has been read and understood. The TL/OSL Experimenter is also required to sign the manual after each revision to signify that the changes are understood. Each individual is responsible for completely understanding the proper operation of the TL/OSL equipment used and for following the guidance contained within this manual. The instructions, protocols, and operating procedures in this manual do not replace, supersede, or alter the hazard mitigation controls identified in the Research Safety Summary (''Thermoluminescence/Optically Stimulated

  4. Clinical dosimetry using mosfets

    International Nuclear Information System (INIS)

    Ramani, Ramaseshan; Russell, Stephen; O'Brien, Peter

    1997-01-01

    Purpose: The use of metal oxide-silicon field effect transistors (MOSFETs) as clinical dosimeters is demonstrated for a number of patients with targets at different clinical sites. Methods and Materials: Commercially available MOSFETs were characterized for energy response, angular dependency of response, and effect of accumulated dose on sensitivity and some inherent properties of MOSFETs. The doses determined both by thermoluminescence dosimetry (TLD) and MOSFETs in clinical situation were evaluated and compared to expected doses determined by calculation. Results: It was observed that a standard calibration of 0.01 Gy/mV gave MOSFET determined doses which agreed with expected doses to within 5% at the 95% confidence limit for photon beams from 6 to 25 MV and electron beams from 5 to 14 MeV. An energy-dependent variation in response of up to 28% was observed between two orientations of a MOSFET. The MOSFET doses compared very well with the doses estimated by TLDs, and the patients tolerated MOSFETs very well. A standard deviation of 3.9% between expected dose and MOSFET determined dose was observed, while for TLDs the standard deviation was 5.1%. The advantages and disadvantages of using MOSFETs for clinical dosimetry are discussed in detail. Conclusion: It was concluded that MOSFETs can be used as clinical dosimeters and can be a good alternative to TLDs. However, they have limitations under certain clinical situations

  5. Thermoluminescence properties of zinc oxide obtained by solution combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R., E-mail: victor.orante@polimeros.uson.mx [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico)

    2014-08-15

    High-dose thermoluminescence dosimetry properties of novel zinc oxide obtained by solution combustion synthesis in a glycine-nitrate process, with a non-stoichiometric value of the elemental stoichiometric coefficient (Φ{sub c}) are presented in this work. Zn O powder samples obtained were annealed afterwards at 900 grades C during 2 h in air. Sintered particles of sizes between ∼ 0.5 and ∼ 2 μm were obtained, according to scanning electron microscopy results. X-ray diffraction indicates the presence of the hexagonal phase of Zn O for the powder samples obtained, before and after thermal annealing, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima; one located at ∼ 149 grades C and another at ∼ 308 grades C, being the latter the dosimetric component of the curve. Dosimetric characterization of non-stoichiometric zinc oxide provided experimental evidence like asymptotic behavior of the Tl signal fading for times greater than 16 h between irradiation and the corresponding Tl readout, as well as the linear behaviour of the dose response without saturation in the dose interval studied (from 12.5 up to 400 Gy). Such characteristics place Zn O phosphors obtained in this work as a promising material for high-dose radiation dosimetry applications (e.g., radiotherapy and food industry). (author)

  6. Thermoluminescence properties of zinc oxide obtained by solution combustion synthesis

    International Nuclear Information System (INIS)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C.; Bernal, R.

    2014-08-01

    High-dose thermoluminescence dosimetry properties of novel zinc oxide obtained by solution combustion synthesis in a glycine-nitrate process, with a non-stoichiometric value of the elemental stoichiometric coefficient (Φ c ) are presented in this work. Zn O powder samples obtained were annealed afterwards at 900 grades C during 2 h in air. Sintered particles of sizes between ∼ 0.5 and ∼ 2 μm were obtained, according to scanning electron microscopy results. X-ray diffraction indicates the presence of the hexagonal phase of Zn O for the powder samples obtained, before and after thermal annealing, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima; one located at ∼ 149 grades C and another at ∼ 308 grades C, being the latter the dosimetric component of the curve. Dosimetric characterization of non-stoichiometric zinc oxide provided experimental evidence like asymptotic behavior of the Tl signal fading for times greater than 16 h between irradiation and the corresponding Tl readout, as well as the linear behaviour of the dose response without saturation in the dose interval studied (from 12.5 up to 400 Gy). Such characteristics place Zn O phosphors obtained in this work as a promising material for high-dose radiation dosimetry applications (e.g., radiotherapy and food industry). (author)

  7. Neutron personnel dosimetry considerations for fusion reactors

    International Nuclear Information System (INIS)

    Barton, T.P.; Easterly, C.E.

    1979-07-01

    The increasing development of fusion reactor technology warrants an evaluation of personnel neutron dosimetry systems to aid in the concurrent development of a radiation protection program. For this reason, current state of knowledge neutron dosimeters have been reviewed with emphasis placed on practical utilization and the problems inherent in each type of dosimetry system. Evaluations of salient parameters such as energy response, latent image instability, and minimum detectable dose equivalent are presented for nuclear emulsion films, track etch techniques, albedo and other thermoluminescent dosimetry techniques, electrical conductivity damage effects, lyoluminescence, thermocurrent, and thermally stimulated exoelectron emission. Brief summaries of dosimetry regulatory requirements and intercomparison study results help to establish compliance and recent trends, respectively. Spectrum modeling data generated by the Neutron Physics Division of Oak Ridge National Laboratory for the Princeton Tokamak Fusion Test Reactor (TFTR) Facility have been analyzed by both International Commission on Radiological Protection fluence to dose conversion factors and an adjoint technique of radiation dosimetry, in an attempt to determine the applicability of current neutron dosimetry systems to deuterium and tritium fusion reactor leakage spectra. Based on the modeling data, a wide range of neutron energies will probably be present in the leakage spectra of the TFTR facility, and no appreciable risk of somatic injury to occupationally exposed workers is expected. The relative dose contributions due to high energy and thermal neutrons indicate that neutron dosimetry will probably not be a serious limitation in the development of fusion power

  8. Synthesis and thermoluminescence properties of CaF2:Tm,Ce nanoparticles

    Directory of Open Access Journals (Sweden)

    M Zahedifar

    2013-10-01

    Full Text Available Calcium fluoride nanoparticles doped with thulium and cerium were synthesized as a novel nanostructure by using the hydrothermal method. The prepared samples were characterized by X-ray diffraction (XRD and energy dispersive spectrometer (EDS. The crystallite size of about 36 nm was estimated employing Scherer’s formula. Its shape and size were also observed by scanning electron microscope (SEM. Computerized glow curve deconvolution (CGCD technique revealed two overlapping thermoluminescence glow peaks at around 402 and 457 K in the complex thermoluminescence glow curve of this phosphor. Other thermoluminescence characteristics of this phosphor such as fading, reuseability and dose response recommend it as a good candidate for high dose dosimetry.

  9. Thermoluminescent dosimetric characterization of the perovskite, KMgF3, activated with lanthanum

    International Nuclear Information System (INIS)

    Sepulveda M, F.

    2003-01-01

    The new ICRP regulation about the Radiological Protection allows to the different groups to study new thermoluminescent materials highly sensitive for dosimetric applications (personal and environmental). This work reports the relative experimental results to the thermoluminescent characteristic of a new preparation of the fluorine perovskite activated with lanthanum absorbed in polytetrafluoroethylene (KMgF 3 : LaF 3 + Ptfe). The main thermoluminescent properties investigated were: the TL response like a function of the absorbed dose, the attainable accuracy in the dose measurement, the reproducibility of the TL readings and the threshold dose. The obtained results were compared with the requirements of the ANSI protocol for the environmental dosimetry, resulting in a very good agreement with the required yields. (Author)

  10. Acceptance Testing of Thermoluminescent Dosimeter Holders.

    Science.gov (United States)

    Romanyukha, Alexander; Grypp, Matthew D; Sharp, Thad J; DiRito, John N; Nelson, Martin E; Mavrogianis, Stanley T; Torres, Jeancarlo; Benevides, Luis A

    2018-05-01

    The U.S. Navy uses the Harshaw 8840/8841 dosimetric (DT-702/PD) system, which employs LiF:Mg,Cu,P thermoluminescent dosimeters (TLDs), developed and produced by Thermo Fisher Scientific (TFS). The dosimeter consists of four LiF:Mg,Cu,P elements, mounted in Teflon® on an aluminum card and placed in a plastic holder. The holder contains a unique filter for each chip made of copper, acrylonitrile butadiene styrene (ABS), Mylar®, and tin. For accredited dosimetry labs, the ISO/IEC 17025:2005(E) requires an acceptance procedure for all new equipment. The Naval Dosimetry Center (NDC) has developed and tested a new non-destructive procedure, which enables the verification and the evaluation of embedded filters in the holders. Testing is based on attenuation measurements of low-energy radiation transmitted through each filter in a representative sample group of holders to verify that the correct filter type and thickness are present. The measured response ratios are then compared with the expected response ratios. In addition, each element's measured response is compared to the mean response of the group. The test was designed and tested to identify significant nonconformities, such as missing copper or tin filters, double copper or double tin filters, or other nonconformities that may impact TLD response ratios. During the implementation of the developed procedure, testing revealed a holder with a double copper filter. To complete the evaluation, the impact of the nonconformities on proficiency testing was examined. The evaluation revealed failures in proficiency testing categories III and IV when these dosimeters were irradiated to high-energy betas.

  11. The Properties of CaSO{sub 4}: Mn Thermoluminescence Dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Bjaerngard, Bengt

    1963-06-15

    The properties of the radio thermoluminescence of CaSO{sub 4}:Mn, used for dosimetry of gamma and roentgen radiation, have been investigated. The light yield of the luminophore has been determined to 1.5 percent for 1 MeV gamma radiation. The dependence of the thermoluminescence light sum on the exposure, the exposure rate, and the exposure time can qualitatively be described by the first order process model, modified by a broad energy distribution of the electron trap depths. Some applications are discussed. The cheapness of the dosimeters, the convenient read-out, and the broad range of measurable exposures suggest that CaSO{sub 4}:Mn can be a valuable complement to other dosimetry systems.

  12. The thermoluminscent dosimetry service of the radiation protection bureau

    International Nuclear Information System (INIS)

    1978-12-01

    Thermoluminescent materials have been used in radiation dosimetry for many years, but their application to nationwide personnel dosimetry has been scarce. An undertaking of this nature requires that methods be established for identification of dosimeters and for fast interpretation and communication of dose to the users across the country. It is also necessary that records of cumulative dose of individual radiation workers be continuously updated, and such records be maintained for a prolonged period. To do this many problems pertinent to associated equpment, vis. the computer, TL reader, their interfacing, and to the operational procedures of the service had to be resolved. Since April 1977, the Radiation Protection Bureau has been providing a Thermoluminescent Dosimetry Service to Canadian radiation workers. This document describes the RPB dosimeter, its characteristics, various aspects of the service, objectives of the service, and how the objective goals of the service are achieved. (auth)

  13. Study of the thermoluminescence properties and kinetics of local natural calcium fluoride in Saudi Arabia

    International Nuclear Information System (INIS)

    Zarie, K.A.

    2006-01-01

    Thermoluminescence (TL) characteristics of local natural calcium fluoride that show light yellowish appearance obtained from a fluoride mine west of Saudi Arabia have been studied. TL glow peaks were observed at 160, 260 and 334 degree C. Thermal treatment and fading effects had been studied. The TL response was observed to increase with increasing dose, as expected, over the dose range used. The kinetic parameters were calculated to satisfy the feasibility of using the present sample as gamma -ray dosimetry

  14. Thermoluminescent characteristics of synthetic hydroxyapatite (SHAp)

    International Nuclear Information System (INIS)

    Alvarez, R.; Rivera, T.; Guzman, J.; Piña-Barba, M.C.; Azorin, J.

    2014-01-01

    This paper presents the experimental results of the thermoluminescent (TL) characteristics of synthetic hydroxyapatite (SHAp) obtained by the sol–gel method. For preparation of the SHAp powders, phosphorus pentoxide (P 2 O 5 ) and calcium nitrate tetrahydrated (Ca(NO 3 ) 2 –4H 2 O) were used. The powders obtained were submitted at different temperatures. The structural and morphological characterization were carried out using X-ray diffraction (XRD) and scanning electron microscopy techniques. TL glow curve exhibited two peaks centered at around 200 °C and 300 °C. TL response of SHAp as a function of gamma absorbed dose was linear over a wide dose range. Fading of the storage information in the samples irradiated was also studied. The experimental results show that the synthetic hydroxyapatite obtained by the sol–gel method may have used in gamma radiation dosimetry applications. - highlights: • Dosimetric characteristics of SHAp under gamma irradiation effect were analyzed • SHAp powders were obtained by Sol–Gel method • Fading anomalous of HAp was performed showing 15% during 90 days • SHAp showed good dosimetric characteristics. • Dosimetric characteristics of SHAp have not been reported yet in the literature before this paper

  15. Thermoluminescence properties of AlN ceramics

    DEFF Research Database (Denmark)

    Trinkler, L.; Christensen, P.; Agersnap Larsen, N.

    1998-01-01

    The paper describes thermoluminescence (TL) properties of AlN:Y2O3 ceramics irradiated with ionising radiation. A high TL sensitivity of AlN:Y2O3 ceramics to radiation encouraged a study of the AlN ceramics for application as a dosimetric material. The paper presents experimental data on: glow...... curve, emission spectrum, dose response, energy dependence, influence of heating rate and fading rate. The measured TL characteristics were compared with those of well-known, widely used TLDs, i.e. LiF:Mg,Ti, LiF:Mg,Cu,P and Al2O3:C. It is concluded that AlN:Y2O3 ceramics showing a radiation sensitivity...... which is approximately 50 times greater than that of LiF:Mg,Ti is an interesting dosimetry material; however due to a high fading rate of the TL of AlN:Y2O3 on storage at room temperature, a further development of the material for improving the fading characteristics is needed for its application...

  16. ESR Dosimetry

    International Nuclear Information System (INIS)

    Baffa, Oswaldo; Rossi, Bruno; Graeff, Carlos; Kinoshita, Angela; Chen Abrego, Felipe; Santos, Adevailton Bernardo dos

    2004-01-01

    ESR dosimetry is widely used for several applications such as dose assessment in accidents, medical applications and sterilization of food and other materials. In this work the dosimetric properties of natural and synthetic Hydroxyapatite, Alanine, and 2-Methylalanine are presented. Recent results on the use of a K-Band (24 GHz) ESR spectrometer in dosimetry are also presented

  17. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 7 2155 http://cern.ch/rp-dosimetry

  18. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service Tel. 7 2155 http://cern.ch/rp-dosimetry

  19. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 72155 http://cern.ch/rp-dosimetry

  20. Dosimetry in nuclear power plants

    International Nuclear Information System (INIS)

    Lastra B, J. A.

    2008-12-01

    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

  1. Study of 225 deg C thermoluminescent of quartz inclusions extracted from cementitious building materials

    International Nuclear Information System (INIS)

    Campos, Simara S.; Almeida, Geangela M. de; Souza, Suzana O.

    2009-01-01

    Incidents of excessive exposure of the population to ionizing radiation could result from a nuclear explosion, the direct exposure to a source theft or loss or an accidental exposure to a source without shielding, for example. During these incidents the victims seldom are using individual protection equipment used in the measurement and control of the doses that were exposed. One of the ways found to the doses assessment due to exposure to this type of accident is the retrospective dosimetry, which determines the excessive doses of radiation exposure, whether chronological or acute, using common materials available in the public domain. The methodology for the application of retrospective dosimetry for thermoluminescence in buildings previously burned, as bricks, it is already well established. Interest is now turning to the use of cementitious building materials such as mortar and concrete to enlarge the scope of application. This study aimed to examine some of these materials and techniques for their possible application in the doses assessment from an accidental irradiation by thermoluminescence. For this the peak about 225 deg C of natural quartz and it extracted of mortar and concrete was certain your stability for the plateau and storage tests, and also the dependence of your luminescent intensity with radiation dose. Presenting a life relatively tans compared enough to that of the accumulation of natural and long radiation sign for dosimetric applications, besides other favorable characteristics, the mortar presented evidence that is possible for retrospective dosimetry through thermoluminescence. (author)

  2. Individual Dosimetry for High Energy Radiation Fields

    International Nuclear Information System (INIS)

    Spurny, F.

    1999-01-01

    The exposure of individuals on board aircraft increased interest in individual dosimetry in high energy radiation fields. These fields, both in the case of cosmic rays as primary radiation and at high energy particle accelerators are complex, with a large diversity of particle types, their energies, and linear energy transfer (LET). Several already existing individual dosemeters have been tested in such fields. For the component with high LET (mostly neutrons) etched track detectors were tested with and without fissile radiators, nuclear emulsions, bubble detectors for both types available and an albedo dosemeter. Individual dosimetry for the low LET component has been performed with thermoluminescent detectors (TLDs), photographic film dosemeters and two types of electronic individual dosemeters. It was found that individual dosimetry for the low LET component was satisfactory with the dosemeters tested. As far as the high LET component is concerned, there are problems with both the sensitivity and the energy response. (author)

  3. Czech results at criticality dosimetry intercomparison 2002.

    Science.gov (United States)

    Frantisek, Spurný; Jaroslav, Trousil

    2004-01-01

    Two criticality dosimetry systems were tested by Czech participants during the intercomparison held in Valduc, France, June 2002. The first consisted of the thermoluminescent detectors (TLDs) (Al-P glasses) and Si-diodes as passive neutron dosemeters. Second, it was studied to what extent the individual dosemeters used in the Czech routine personal dosimetry service can give a reliable estimation of criticality accident exposure. It was found that the first system furnishes quite reliable estimation of accidental doses. For routine individual dosimetry system, no important problems were encountered in the case of photon dosemeters (TLDs, film badge). For etched track detectors in contact with the 232Th or 235U-Al alloy, the track density saturation for the spark counting method limits the upper dose at approximately 1 Gy for neutrons with the energy >1 MeV.

  4. Thermoluminescent dosimetry in the radiodiagnostic area of the INNSZ

    International Nuclear Information System (INIS)

    Azorin V, J.C.; Azorin N, J.; Rivera M, T.

    1998-01-01

    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)

  5. Extremity dosimetry in nuclear medicine services using thermoluminescent detectors

    International Nuclear Information System (INIS)

    Mebhah, D.; Djeffal, S.; Badreddine, A.; Medjahed, M.

    1993-01-01

    The Radiation Protection and Safety Centre in Algiers provides two types of dosemeters, one for monitoring doses to the whole body and skin and the other one for monitoring doses to the extremities of the body. In nuclear medicine services and radiopharmaceutical laboratories, hands and arms are often closer to a given radiation source than the main part of the body and therefore receive greater doses. In this context, extremity doses have been measured by a ring dosemeter and by a fingertip ultra-thin dosemeter. The ring dosemeter consists of a metallic ring with a circular indentation to hold a LiF chip which is covered with a 10 mg.cm -2 shrinkable black polyamide layer. The ultra-thin dosemeter contains a 5 mg.cm -2 LiF element for measuring doses at a depth of 7 mg.cm -2 . These extremity dosemeters have been characterised before their use in the field. They have also been tested using radioisotopes of various energies. The doses received by the monitored workers were correlated with the amount of the handled activity. The doses obtained using the fingertip and the ring dosemeters are presented and discussed from a radiological point of view. (author)

  6. Accuracy of megavolt radiation dosimetry using thermoluminescent lithium fluoride.

    Science.gov (United States)

    Rudén, B I; Bengtsson, L G

    1977-04-01

    The relative light output per Gy in polystyrene for roentgen beams of 6 and 42 MV and electrons between 2.2 and 34.5 MeV relative to 60Co gamma radiation is reported for different kinds of LiF dosemeters. The distribution of the absorbed dose inside a 0.25 and 0.4 mm thick LiF-teflon disc surrounded by polystyrene and irradiated with 60Co, 42 MV roentgen radiation and 39 MeV electrons was measured using 0.01 and 0.02 mm thick Lif-teflon discs. The measurements show that the absorbed dose distribution in the dosemeter depends on the energy of the radiation. When flat dosemeters were used, differences between the signals measured at the two orientations possible during read-out could easily amount to several per cent, and for this reason 0.4 mm and 0.5 mm LiF-Teflon discs were not trusted when the highest accuracy was required. The cavity theory by Burlin does not account for the phenomena caused by differences in electron scattering properties of the dosemeter and the phantom material. Some suggestions are presented for a different cavity theory for flat dosemeters dealing also with these phenomena. It describes the results to about the same degree of approximation as the Burlin theory, and fails to explain the observed energy dependence for electrons.

  7. Thermoluminescent dosimetry in two laboratories of the ININ

    International Nuclear Information System (INIS)

    Cejudo, R.; Gonzalez, P.R.; Azorin N, J.

    2002-01-01

    The effects of the high doses of radiation are well known, but the effects caused by the exposure to low level radiations do not. However it is well known that the dose by small scale what this was as long as it comes from the ionizing radiation it has the enough energy for altering the normal performance of the cells in the living beings. In this work the obtained results in the measurement of the radiation levels in two laboratories of the ININ are presented. One of them located in the Gamma source building (FG) and the other one is now know as Connected to Basic and Environmental Sciences (ACBA). This work was motivated by the nonconformist personnel which works in the last laboratory, since this place was used during many years as warehouse of radioactive wastes, therefore it is expected that the dose levels were higher. The dose was measured with Tl of CaSO 4 :Dy + Ptfe dosemeters developed in the ININ. The results showed that the radiation levels in both laboratories are similar and they are under of the recommended levels for public in general, except a point in ACBA where the dose exceeded in a 64% that value. (Author)

  8. Thermoluminescence glow curve analysis and CGCD method for erbium doped CaZrO{sub 3} phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Ratnesh, E-mail: 31rati@gmail.com [Department of Physics, Bhilai Institute of Technology, Raipur, 493661 (India); Chopra, Seema [Department Physics, G.D Goenka Public School (India)

    2016-05-06

    The manuscript report the synthesis, thermoluminescence study at fixed concentration of Er{sup 3+} (1 mol%) doped CaZrO{sub 3} phosphor. The phosphors were prepared by modified solid state reaction method. The powder sample was characterized by thermoluminescence (TL) glow curve analysis. In TL glow curve the optimized concentration in 1mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) techniaue. Trapping parameters gives the information of dosimetry loss in prepared phosphor and its usability in environmental monitoring and for personal monitoring. CGCD is the advance tool for analysis of complicated TL glow curves.

  9. Dosimetry methods

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, A.; Kovacs, A.

    2003-01-01

    Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application....

  10. Diagnostic radiology dosimetry: status and trends

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-15

    Full text: Medical radiation is by far the largest man-made source of public exposure to ionizing radiation. Since 1970 the expression of protection standards shifted from a dose- to a risk-based approach, with dose limits established to yield risks to radiation workers comparable with those for workers in other safe industries. Another hand, worldwide interest in patient dose measurement was stimulated by the publication of Patient Dose Reduction in Diagnostic Radiology by the UK National Radiological Protection Board (NRPB). In response to heightened awareness of the importance of patient dose contributed by radiology procedures, there has been a general trend to effect control of patient doses by applying the principles of optimization coupled with an increase in regulatory enforcement. In this sense, thermoluminescent dosimetry (TLD) has been actively proposed in the last 3 decades thanks to their successful applications in diagnostic radiology. At the same time, it is emerged as the best radiation dosimetry method. The present work presents advantages of thermoluminescent dosimetry for X-ray beams measurements and its optimization. (Author)

  11. Diagnostic radiology dosimetry: status and trends

    International Nuclear Information System (INIS)

    Rivera M, T.

    2015-10-01

    Full text: Medical radiation is by far the largest man-made source of public exposure to ionizing radiation. Since 1970 the expression of protection standards shifted from a dose- to a risk-based approach, with dose limits established to yield risks to radiation workers comparable with those for workers in other safe industries. Another hand, worldwide interest in patient dose measurement was stimulated by the publication of Patient Dose Reduction in Diagnostic Radiology by the UK National Radiological Protection Board (NRPB). In response to heightened awareness of the importance of patient dose contributed by radiology procedures, there has been a general trend to effect control of patient doses by applying the principles of optimization coupled with an increase in regulatory enforcement. In this sense, thermoluminescent dosimetry (TLD) has been actively proposed in the last 3 decades thanks to their successful applications in diagnostic radiology. At the same time, it is emerged as the best radiation dosimetry method. The present work presents advantages of thermoluminescent dosimetry for X-ray beams measurements and its optimization. (Author)

  12. Evaluation of thermoluminescent BeO samples in standard radiotherapy beams; Avaliacao de amostras termoluminescentes de BeO em feixes padroes de radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, Daniela P.; Silva, Jonas O.; Caldas, Linda V.E., E-mail: daniela.piai.groppo@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-08-15

    Beryllium oxide thermoluminescent samples were evaluated in standard radiotherapy beams of low energy. Results for response reproducibility, dose-response curve and energy dependence were obtained. The lower detection limit was determined. The pellets of BeO showed their usefulness for beam dosimetry. (author)

  13. Preparation and structural characterization of the thermoluminescent material CaSO{sub 4}: Dy; Preparacion y caracterizacion estructural del material termoluminiscente CaSO{sub 4}: Dy

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez R, A.; Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Gonzalez M, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Rivera, T. [CICATA-IPN, Legaria 694, 11500 Mexico D.F. (Mexico)

    2005-07-01

    The grade of crystallinity of a material is important so that the one is presented the thermoluminescence phenomenon; for what is necessary to study those structural characteristic of a TL material and to correlate them with its TL response when being irradiated with ionizing radiation. The calcium sulfate activated with Dysprosium (CaSO{sub 4}: Dy) it is a material that has demonstrated its efficiency in the dosimetry of the ionizing radiation for the thermoluminescence method. In this work the structural characterization of this prepared material for the recrystallization method by means of the evaporation of the solvent and their relationship with their TL response is presented. The results showed that the best material to be used in thermoluminescent dosimetry presents a crystalline structure in orthorhombic phase and a particle size in the interval of 80 {mu}m to 200 {mu}m. (Author)

  14. Thermoluminescent analysis of CaSO{sub 4} composites activated with rare earths; Analise termoluminescente de compositos de CaSO{sub 4} ativado com terras raras

    Energy Technology Data Exchange (ETDEWEB)

    Junot, D.O.; Chagas, M.A.P.; Souza, D.N., E-mail: danilo.junot@hotmail.com, E-mail: mchagasfisica@gmail.com, E-mail: divanizi@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Fisica

    2013-07-01

    Since the thermoluminescence started to be applied to the dosimetry of ionizing radiation in 1940 different materials detectors have been proposed, and one of the most common is CaSO{sub 4}. The motivation of this work was to produce crystals of CaSO{sub 4} doped with rare earth elements such as europium (Eu), neodymium (Nd) and thulium (Tm). It was also produced crystals of CaSO{sub 4}:Ag. The interest in the production of these materials was to investigate other methods of production of thermoluminescent materials. The results show that the CaSO{sub 4}:Tm is more suitable for use in the thermoluminescent dosimetry. Although not the most intense peak, the peak at 170 °C could be a dosimetric peak. Analyses showed that all samples have a TL response proportional to the dose absorbed. (author)

  15. The personal dosimetry in Mexico

    International Nuclear Information System (INIS)

    Salazar, M.A.

    2006-01-01

    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

  16. Thermoluminescence under an exponential heating function: I. Theory

    International Nuclear Information System (INIS)

    Kitis, G; Chen, R; Pagonis, V; Carinou, E; Kamenopoulou, V

    2006-01-01

    Constant temperature hot gas readers are widely employed in thermoluminescence dosimetry. In such readers the sample is heated according to an exponential heating function. The single glow-peak shape derived under this heating condition is not described by the TL kinetics equation corresponding to a linear heating rate. In the present work TL kinetics expressions, for first and general order kinetics, describing single glow-peak shapes under an exponential heating function are derived. All expressions were modified from their original form of I(n 0 , E, s, b, T) into I(I m , E, T m , b, T) in order to become more efficient for glow-curve deconvolution analysis. The efficiency of all algorithms was extensively tested using synthetic glow-peaks

  17. The NRPB automated thermoluminescent dosemeter and dose record keeping system

    International Nuclear Information System (INIS)

    Dennis, J.A.; Marshall, T.O.; Shaw, K.B.

    1975-03-01

    This report describes the thermoluminescent personal radiation dosemeter and its associated automated processing equipment, which are being developed by the National Radiological Protection Board, together with the operation of a computerised dosemeter issue and record keeping system. The main justifications for introducing these systems are improvements in the organizational efficiency of the maintenance of individual dose records, a more flexible and accurate dosimetry system, and economics in operational costs. The dosemeter is based on a numbered aluminium plate containing two lithium fluoride in polytetrafluorethylene disks for the measurement of surface and body dose. This dosemeter is wrapped in thin plastic and labelled with the wearer's name and address. On return, the dosemeter is checked automatically for radioactive contamination; it is unwrapped and evaluated; the dose readings are included in the wearer's stored dose record; the dosemeter is annealed and is then available for re-issue to another wearer. Dose reports and warnings are automatically issued to the wearer or his employer. (author)

  18. Assessment of CVD diamond as a thermoluminescence dosemeter material

    International Nuclear Information System (INIS)

    Borchi, E.; Furetta, C.; Leroy, C.

    1996-01-01

    Diamond has a low atomic number (Z = 6) and is therefore essentially soft tissue (Z = 7.4) equivalent. As such, diamond is an attractive material for applications in dosimetry in which the radiation absorption in the sensor material should be as close as possible to that of soft tissue. Synthetic diamond prepared by chemical vapour deposition (CVD) offers an attractive option for this application. The aim of the present work is to report results on the thermoluminescence (TL) properties of CVD diamond samples. The annealing procedures, the linearity of the TL response as a function of dose, a short-term fading experiment and some kinetic properties have been investigated and are reported here. (Author)

  19. CaSO4: Dy + Teflon thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Campos, L.L.

    1986-01-01

    A pellet dosemeter of CaSO 4 : Dy + Teflon was developed at IPEN. CaSO 4 : Dy thermoluminescent phosphor, grown in the Dosimetric Materials Production Laboratory was chosen, due to its high sensitivity, ease of preparation and comparatively low cost. Pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. Extensive work was done to study in detail all CaSO 4 : Dy pellets characteristics from the point of view of dosimetry with the purpose of introducing it in the routine use. A filter combination providing an energy independent response from 20 KeV to 1,25 MeV was obtained. The dosemeter consists of three pellets sealed between two thin plastic sheets and placed under plastic and lead filters. The combination of these tree filters allows the exposure as well as the energy determination of an unknown source. (Author) [pt

  20. ESR/Alanine {gamma}-dosimetry in the 10-30 Gy range

    Energy Technology Data Exchange (ETDEWEB)

    Fainstein, C. E-mail: cfainstein@cab.cnea.gov.ar; Winkler, E.; Saravi, M

    2000-05-15

    We report Alanine Dosimeter preparation, procedures for using the ESR/Dosimetry method, and the resulting calibration curve for {gamma}-irradiation in the range from 10-30 Gy. We use calibration curve to measure the irradiation dose in {gamma}-irradiation of human blood, as required in Blood Transfusion Therapy. The ESR/Alanine results are compared against those obtained using the thermoluminescent dosimetry (TLD) method.

  1. Contribution of the operational dosimetry in the radiation protection optimization in a nuclear medicine service

    International Nuclear Information System (INIS)

    Herit, S.; Cosculluela, S.; Lambert, B.; Gras, H.

    2007-01-01

    Beyond its contribution in the personnel dosimetric surveillance, the operational dosimetry is a very efficient educational tool, of easy use. This study is lengthened by the setting up in 2007 of a job study in order to redefine the service zoning and by an evaluation of the extremities dosimetry with the help of thermoluminescent rings, in order to optimize the practices during the phase of preparation and injection. (N.C.)

  2. Dosimetry optimization at COGEMA-La Hague

    International Nuclear Information System (INIS)

    Kalimbadjian, J.

    2000-01-01

    At the present time, the la Hague site strives to apply international recommendations together with national regulations concerning radiation protection, and especially the respect of limitation and optimization principles. The application of these principles is based on the implementation of a passive dosimetry and an active dosimetry. The monthly passive dosimetry is monitored by means of a photographic dosimetry film, completed with lithium fluorine thermoluminescent film badges. This personal dosimetry common to X, β, γ and neutron radiations is carried out in close relationship between the Radiation Protection Department, the Occupational Medical Department and the staff running the Plant. The application or ALARA's principle as well as that of radiation protection optimization implies to implement a complementary active dosimetry enabling to gain in real time, the personal dosimetry of each intervening person, either they be COGEMA's workers or external companies'. This active dosimetry provides with following information: This preventive dosimetry is based on the knowledge of doses integration in real time and is fitted with alarm thresholds according to the total amount of doses and dose rates. Thresholds on the dose rate are also set relatively to the radiological environment. This knowledge of doses and dose rates allows a stricter management of the works, while analyzing them according to the nature of the work, to the location and to the skills of the intervening people. This dosimetry allows to analyze and optimize doses integration according to the works nature for the whole intervening staff. The la Hague Site has developed an active personal dosimetry system, common to every intervening person, COGEMA or external companies. The DOSICARD was thus elaborated, shaped as an electronic dosimeter fitted with an alarm and a smart card. The access to controlled areas is conditioned to information given by the DOSICARD concerning medical aptitudes and

  3. Study on the thermoluminescent properties of K{sub 2}YF{sub 5} and K{sub 2}GdF{sub 5} crystals doped with optically active trivalent ions for gamma and neutrons dosimetry; Estudo das propriedades termoluminescentes de cristais de K{sub 2}YF{sub 5} e K{sub 2}GdF{sub 5} dopados com ions trivalentes opticamente ativos para dosimetria gama e de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edna Carla da

    2008-07-01

    In this work, the thermoluminescent (TL) properties of both double potassium yttrium fluoride (K{sub 2}YF{sub 5}) and double potassium gadolinium fluoride (K{sub 2}GdF{sub 5}) crystals doped with optically active rare earth ions were investigated from the point of view of gamma and neutron dosimetry. Crystalline platelets with thickness of about 1 mm, synthesized under hydrothermal conditions, were irradiated in order to study TL sensitivity, as well as dose and energy response, reproducibility and fading, in terms of Ce{sup 3+}, Tb{sup 3+}, Dy{sup 3+}, e Pr{sup 3+} concentrations. The K{sub 2}YF{sub 5} crystals doped with 1.0 at por cent Dy{sup 3+} have been found to have an excellent linear TL response to X and gamma photons, in the range of 0.01 to 10 mGy. The TL output is comparable to that of CaS0{sub 4}:Mn dosemeters. The main peak at 130 deg C has been found to have a TL response for 41.1 keV X-ray energy 32 times higher than that for 662 keV gamma rays. This fact points out that the K{sub 2}Y{sub 0.99}Dy{sub 0.01}F{sub 5} crystals have great potential for X-rays diagnostic and/or industrial radiography. On the other hand, the K{sub 2}GdF{sub 5} crystals doped with 5.0 at por cent Dy{sup 3+} have been found to have the better TL response for gamma and fast neutron radiation, among the dopants studied. For gamma fields the TL response was linear for doses ranging from 0.1 to 200 mGy. The TL peak around 200 deg C can be deconvoluted into four individual peaks, all of them with linear behavior. For fast neutron radiation produced by an {sup 241}Am{sub B}e source, the TL responses for doses ranging from 0.6 to 12 mSv were also linear and comparable to that of commercial TLD-600, irradiated at same conditions. The TL emission due to neutrons was in the high temperature range, above 200 deg C. These results points out that K{sub 2}Gd{sub 0.95}Dy{sub 0.05}F{sub 5} crystals are good candidates for use in neutron dosimetry applications. (author)

  4. Chemical dosimetry system for criticality accidents.

    Science.gov (United States)

    Miljanić, Saveta; Ilijas, Boris

    2004-01-01

    Ruder Bosković Institute (RBI) criticality dosimetry system consists of a chemical dosimetry system for measuring the total (neutron + gamma) dose, and a thermoluminescent (TL) dosimetry system for a separate determination of the gamma ray component. The use of the chemical dosemeter solution chlorobenzene-ethanol-trimethylpentane (CET) is based on the radiolytic formation of hydrochloric acid, which protonates a pH indicator, thymolsulphonphthalein. The high molar absorptivity of its red form at 552 nm is responsible for a high sensitivity of the system: doses in the range 0.2-15 Gy can be measured. The dosemeter has been designed as a glass ampoule filled with the CET solution and inserted into a pen-shaped plastic holder. For dose determinations, a newly constructed optoelectronic reader has been used. The RBI team took part in the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002, with the CET dosimetry system. For gamma ray dose determination TLD-700 TL detectors were used. The results obtained with CET dosemeter show very good agreement with the reference values.

  5. Effect of thermal decomposition of hydroxyapatite on the thermoluminescent response

    International Nuclear Information System (INIS)

    Sandoval C, K. J.; Zarate M, J.; Lemus R, J.; Rivera M, T.

    2014-08-01

    In this work, a study on the thermoluminescence (Tl) induced by gamma radiation in synthetic hydroxyapatite (Hap) annealed at different temperatures obtained by the precipitation method is presented. Synthesis of hydroxyapatite Hap was carried out starting from inorganic precursors [Ca(NO 3 ) 2 ·4H 2 O and (NH 4 ) 2 HPO 4 ]. The precipitate was filtered, washed, dried and then the powder was calcined at different temperatures until the Hap decomposition. The structural and morphological characterization was carried out using both X-ray diffraction (XRD) and scanning electron microscopy (Sem) techniques. Thermoluminescent (Tl) properties of Hap powders were irradiated at different gamma radiation doses. According to X ray diffraction patterns, the tricalcium diphosphate phase (Tcp) appear when the Hap was calcined at 900 grades C. Tl glow curve showed two peaks located at around 200 and 300 grades C, respectively. Tl response as a function of gamma radiation dose was in a wide range from 25 to 100 Gy. The fading of the Tl response at 134 days after irradiation was measured. Experimental results showed that the synthetic hydroxyapatite obtained by precipitation technique may have dosimetric applications when is annealed at temperature of 900 grades C, where the Tcp phase appears and contributes to Tl response, which opens the possibility of using this biomaterials in the area of dosimetry, as they are generally used for biomedical implants. (author)

  6. Thermoluminescence of double fluorides doped with rare earths

    International Nuclear Information System (INIS)

    Azorin N, J.; Sanchez R, A.; Khaidukov, N.M.

    2004-01-01

    In this work the thermoluminescent characteristics of double fluorides K 2 YF 5 , K 2 GdF 5 and K 2 LuF 5 doped are presented with Tb 3+ , studied in the interval of temperature from 30 to 400 C. The materials that presented better answer to the irradiation with particles beta and with ultraviolet light they were the K 2 YF 5 : Tb (1% at. Tb 3+ ) and the K 2 LuF 5 : Tb (1% at. Tb 3+ ); while the K 2 YF 5 : Tb to high concentrations (10% and 20% at. Tb 3+ ) and the K 2 LuF 5 : Tb (1% at. Tb 3+ ) and the K 2 LuF 5 : Tb (1% at. Tb 3+ ) they presented an acceptable answer in front of the gamma radiation. The intensity of the Tl answer induced in these materials is a decisive factor to continue studying its dosimetric characteristics, what allows to consider them as the base for the development of potential materials to use them in the dosimetry of beta particles, of the UV light of the gamma radiation using the thermoluminescence method. (Author)

  7. Quality control of dosimetric systems using thermoluminescent crystals

    International Nuclear Information System (INIS)

    Mahecha, L.; Plazas, M. C.; Machado, M.; Perea, M. D.

    2006-01-01

    To achieve an optimal tumoral control to prostate cancer in early and locally advanced stages, it is necessary to increase the dose with a low mobility probability at the vesicle an rectal level. This is achieved through conformal radiotherapy. The Instituto Nacional de Cancerologia uses this technique, but two questions arise from the medical-physicists and medical radio-oncologist: In accordance with clinical protocols, the conformal radiotherapy delivers a low dose to the adjacent healthy tissues. What experimental method exists that can prove with certainly the veracity of this affirmation?. And, Do the dosimetric simulation system calculate suitable the dose for each tissues?. Through thermoluminescent dosimetry and the use of a physical simulator,we measured the absorbed dose at the target volume and the adjacent tissues using conformal and conventional radiotherapy. We proved that organs such as the rectum and bladder, receiver a minor dose in conformal radiotherapy, hence reducing their mobility probability. In addition, the readings from the thermoluminescent dosimeters and the doses calculated by the ECLIPSE dosimetric system were compared, concluding that the patient's prescribed dose is effectively delivered as recommended by the quality control program in radiotherapy. (Author)

  8. Effect of thermal decomposition of hydroxyapatite on the thermoluminescent response

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval C, K. J.; Zarate M, J.; Lemus R, J. [Universidad Michoacana de San Nicolas de Hidalgo, Instituto de Investigaciones Metalurgicas, Ciudad Universitaria, Edificio U, 58060 Morelia, Michoacan (Mexico); Rivera M, T., E-mail: karlasandovalc@gmail.com [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

    2014-08-15

    In this work, a study on the thermoluminescence (Tl) induced by gamma radiation in synthetic hydroxyapatite (Hap) annealed at different temperatures obtained by the precipitation method is presented. Synthesis of hydroxyapatite Hap was carried out starting from inorganic precursors [Ca(NO{sub 3}){sub 2}·4H{sub 2}O and (NH{sub 4}){sub 2}HPO{sub 4}]. The precipitate was filtered, washed, dried and then the powder was calcined at different temperatures until the Hap decomposition. The structural and morphological characterization was carried out using both X-ray diffraction (XRD) and scanning electron microscopy (Sem) techniques. Thermoluminescent (Tl) properties of Hap powders were irradiated at different gamma radiation doses. According to X ray diffraction patterns, the tricalcium diphosphate phase (Tcp) appear when the Hap was calcined at 900 grades C. Tl glow curve showed two peaks located at around 200 and 300 grades C, respectively. Tl response as a function of gamma radiation dose was in a wide range from 25 to 100 Gy. The fading of the Tl response at 134 days after irradiation was measured. Experimental results showed that the synthetic hydroxyapatite obtained by precipitation technique may have dosimetric applications when is annealed at temperature of 900 grades C, where the Tcp phase appears and contributes to Tl response, which opens the possibility of using this biomaterials in the area of dosimetry, as they are generally used for biomedical implants. (author)

  9. Review of retrospective dosimetry techniques for external ionising radiation exposures

    International Nuclear Information System (INIS)

    Ainsbury, E. A.; Bakhanova, E.; Barquinero, J. F.; Brai, M.; Chumak, V.; Correcher, V.; Darroudi, F.; Fattibene, P.; Gruel, G.; Guclu, I.; Horn, S.; Jaworska, A.; Kulka, U.; Lindholm, C.; Lloyd, D.; Longo, A.; Marrale, M.; Monteiro Gil, O.; Oestreicher, U.; Pajic, J.; Rakic, B.; Romm, H.; Trompier, F.; Veronese, I.; Voisin, P.; Vral, A.; Whitehouse, C. A.; Wieser, A.; Woda, C.; Wojcik, A.; Rothkamm, K.

    2011-01-01

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements. (authors)

  10. Clinical dosimetry

    International Nuclear Information System (INIS)

    Rassow, J.

    1973-01-01

    The main point of this paper on clinical dosimetry which is to be understood here as application of physical dosimetry on accelerators in medical practice, is based on dosimetric methodics. Following an explanation of the dose parameters and description of the dose distribution important for clinical practice as well as geometric irradiation parameters, the significance of a series of physical parameters such as accelerator energy, surface energy of average stopping power etc. is dealt with in detail. Following a section on field homogenization with bremsstrahlung and electron radiation, details on dosimetry in clinical practice are given. Finally, a few problems of dosemeter or monitor calibration on accelerators are described. The explanations are supplemented by a series of diagrams and tables. (ORU/LH) [de

  11. Neutron dosimetry of the Little Boy device

    International Nuclear Information System (INIS)

    Pederson, R.A.; Plassmann, E.A.

    1984-01-01

    Neutron dose rates at several angular locations and at distances out to 0.5 mile have been measured during critical operation of the Little Boy replica. We used modified remmetes and thermoluminescent dosimetry techniques for the measurements. The present status of our analysis is presented including estimates of the neutron-dose-relaxation length in air and the variation of the neutron-to-gamma-ray dose ratio with distance from the replica. These results are preliminary and are subject to detector calibration measurements

  12. Radiation dosimetry for the space shuttle program

    International Nuclear Information System (INIS)

    Jones, K.L.; Richmond, R.G.; Cash, B.L.

    1985-01-01

    Radiation measurements aboard the Space Shuttle are made to record crew doses for medical records, to verify analytical shielding calculations used in dose predictions and to provide dosimetry support for radiation sensitive payloads and experiments. Low cost systems utilizing thermoluminescent dosimeters, nuclear track detectors and activation foils have been developed to fulfill these requirements. Emphasis has been placed on mission planning and dose prediction. As a result, crew doses both inside the orbiter and during extra-vehicular activities have been reasonable low. Brief descriptions of the space radiation environment, dose prediction models, and radiation measurement systems are provided, along with a summary of the results for the first fourteen Shuttle flights

  13. Dosimetry and quality control in radiodiagnosis

    International Nuclear Information System (INIS)

    Le Gouic, M.

    1983-07-01

    This work deals with physics of radiodiagnosis. In a first part a study of the characteristics of different kinds of radiological equipments and a quality assurance of some of them (standard radiography, coronarography and computed tomography) have been performed. The second part deals with patient irradiation. After a bibliographic study of radiodiagnosis dosimetry, two kinds of dosimetric measures have been made: ''in vitro'' measures, using a phantom, that had allowed to calibrate the equipment and to improve the individual irradiation card, and ''in vivo'' measures. For the first types of measures ionization chambers, have been used for the second thermoluminescent dosimeters [fr

  14. Studies in dosimetry using stimulated exoelectron emission

    International Nuclear Information System (INIS)

    Petel, Maurice.

    1976-06-01

    Some applications of the stimulated exoelectron emission in radiation dosimetry are discussed. The principles which govern the phenomenon are presented. The apparatus, in particular the counter, used to monitor the emission is discussed with reference to both optical and thermal stimulation. The correlation existing between thermoluminescence and thermally stimulated exoelectron emission were studied in both lithium fluoride and aluminium oxide. Furthermore, aluminium oxides from different sources were examined, and one of these, chosen to investigate the dosimetric properties of this material using both methods of stimulation [fr

  15. Study of a new glass matrix by the thermoluminescence technique; Estudo de uma nova matriz vitrea pela tecnica de termoluminescencia

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pamela Z.; Vedovato, Uly P.; Cunha, Diego M. da; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P., E-mail: anapaula.perini@ufu.br [Universidade Federal de Uberlandia (INFIS/UFU), MG (Brazil). Instituto de Fisica; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Carrera, Betzabel N.S.; Watanabe, Shigueo [Universidade de Sao Paulo (IF/USP), Sao Paulo, SP (Brazil). Instituto de Fisica

    2015-07-01

    The thermoluminescence technique is widely used for both personal and for high-dose dosimetry. In this work, the thermoluminescence technique was utilized to study a new glass matrix, with nominal composition of 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.20BaO.50B{sub 2}O{sub 3} (mol%), irradiated with different doses in a {sup 60}Co source. The glow curves and the dose-response curve were obtained for radiation doses between 50 Gy and 900 Gy. The results showed that this new glass matrix presents potential use in high-dose dosimetry. (author)

  16. Thermoluminescence property of nano scale Al{sub 2}O{sub 3}: C by combustion method

    Energy Technology Data Exchange (ETDEWEB)

    Bharthasaradhi, R.; Nehru, L. C. [Department of Medical Physics, School of Physics, Bharathidasan University, Tiruchirappalli-620 024, Tamilnadu (India)

    2016-05-23

    In this study, thermoluminescence dosimetry material of carbon doped aluminium oxide by combustion method using Aluminium nitrate and Glycine. The Structure of the prepared Sample was carried out by XRD. The sample was nano crystalline in nature. Having hexagonal structure with unit cell parameters a=4.75Å, C=12.99Å. The surface morphology of the prepared nanopowder was carried out through (SEM). The morphology of the prepared sample is platelet structure and functional group analysis carried out through FT-IR Spectrum. The prepared sample was irradiated through γ-ray CO{sup 60} (100 Gy) was used as γ-ray source. The thermoluminescence glow curve of the irradiated sample showed an isolated peak at around 200°C. The result suggest the prepared nanopowder is suitable for medical radiation dosimetry.

  17. Thermoluminescence of zirconium oxide nanostructured to mammography X-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, L.L. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Rivera, T., E-mail: trivera@ipn.mx [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Roman, J. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Azorin, J. [Universidad Autonoma Metropolitana-Iztapalapa. Av. San Rafael Atlixco 187, 09340 Mexico D.F. (Mexico); Gaona, E. [Universidad Autonoma Metropolitana-Xochimilco. Calz. Del Hueso 1100, 04960 Mexico D.F. (Mexico)

    2012-07-15

    In the present work thermoluminescent (TL) response of zirconium oxide (ZrO{sub 2}) nanostructured induced by mammography X-ray radiation was investigated. Measurements were made of the response per unit air kerma of ZrO{sub 2} with mammography equipment parameters (semiautomatic exposure control, 24 kVp and 108 mAs). The calibration curves were obtained by simultaneously irradiating ZrO{sub 2} samples and ion chamber. Samples of ZrO{sub 2} showed a linear response as a function of entrance skin air kerma. The observed results in TL properties suggest that ZrO{sub 2} nanostructured could be considered as an effective material for X-ray beams dosimetry if appropriate calibration procedures are performed. - Highlights: Black-Right-Pointing-Pointer X-ray low energy thermoluminescent of ZrO{sub 2} dosimeter is developed. Black-Right-Pointing-Pointer Air kerma measurements were made by thermoluminescent dosimeter ZrO{sub 2} using mammography equipment parameters. Black-Right-Pointing-Pointer Entrance surface skin doses were made using thermoluminescent dosimeter of ZrO{sub 2} to X-ray beam quality control.

  18. Thermoluminescence of zirconium oxide nanostructured to mammography X-ray beams

    International Nuclear Information System (INIS)

    Palacios, L.L.; Rivera, T.; Roman, J.; Azorín, J.; Gaona, E.

    2012-01-01

    In the present work thermoluminescent (TL) response of zirconium oxide (ZrO 2 ) nanostructured induced by mammography X-ray radiation was investigated. Measurements were made of the response per unit air kerma of ZrO 2 with mammography equipment parameters (semiautomatic exposure control, 24 kVp and 108 mAs). The calibration curves were obtained by simultaneously irradiating ZrO 2 samples and ion chamber. Samples of ZrO 2 showed a linear response as a function of entrance skin air kerma. The observed results in TL properties suggest that ZrO 2 nanostructured could be considered as an effective material for X-ray beams dosimetry if appropriate calibration procedures are performed. - Highlights: ► X-ray low energy thermoluminescent of ZrO 2 dosimeter is developed. ► Air kerma measurements were made by thermoluminescent dosimeter ZrO 2 using mammography equipment parameters. ► Entrance surface skin doses were made using thermoluminescent dosimeter of ZrO 2 to X-ray beam quality control.

  19. Thermoluminescent characteristics of CaSO4:Dy+PTFE irradiated with high energy electron beams

    International Nuclear Information System (INIS)

    Alvarez, R.; Rivera, T.; Calderon, J. A.; Jimenez, Y.; Rodriguez, J.; Oviedo, O.; Azorin, J.

    2011-10-01

    In the present work thermoluminescent response of dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO 4 :Dy+PTFE) under high electron beam irradiations from linear accelerator for clinical applications was investigated. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator Varian, C linac 2300C/D, for clinical practice purpose. The electron irradiations were obtained by using the water solid in order to guarantee electronic equilibrium conditions. Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO 4 :Dy+PTFE were conducted under high electron beams irradiations. The thermoluminescent response of the pellets showed and intensity peak centered at around 235 C. Thermoluminescent response of CaSO 4 :Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO 4 :Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. (Author)

  20. Development of a transfer instrument for neutron dosimetry intercomparison

    International Nuclear Information System (INIS)

    Greene, D.; Miles, J.

    1974-01-01

    Comparisons are reported for fast neutron dosemeters which were designed to be transportable so as to enable intercomparisons between institutions using neutrons for radiotherapy or radiobiology. The systems considered are : 1) the ferrous sulphate dosemeter, 2) the lithium fluoride thermoluminescent dosemeter, 3) ionization chambers with various walls and gases. Work on photographic film dosimetry indicated that the system was not suitable and was not pursued. The sources used were 60 Co, the cyclotron at Hammersmith Hospital in London and 252 Cf

  1. The zero-power basis of fast reactor dosimetry

    International Nuclear Information System (INIS)

    Sanders, J.E.

    1978-06-01

    Predictions of reaction rates, atomic displacements, and gamma-ray energy deposition in the Prototype Fast Reactor are based on cross-section data and calculation methods validated against the results of zero-power experiments. The paper reviews work in Zebra relevant to this dosimetry, including neutron spectrometry, power mapping, foil activations within core heterogeneities, and measurements with thermoluminescent detectors. Comparisons of experiment and calculation are discussed in relation to the accuracies required to meet materials testing objectives. (author)

  2. The zero-power basis of fast reactor dosimetry

    International Nuclear Information System (INIS)

    Sanders, J.E.

    1978-06-01

    Predictions of reaction rates, atomic displacements, and gamma-ray energy deposition in the Prototype Fast Reactor are based on cross-section data and calculation methods validated against the results of zero-power experiments. The paper reviews work in Zebra relevant to this dosimetry, including neutron spectrometry, power mapping, foil activations within core heterogeneities, and measurements with thermoluminescent detectors. Comparisons of experiment and calculation are discussed in relation to the accuracies required to meet material testing objectives. (author)

  3. Observations on the activation energy determination through the peak temperature at the maximum in thermoluminescence (Tl) experiments

    International Nuclear Information System (INIS)

    Furetta, C.; Azorin, J.; Rivera, T.

    2003-01-01

    The aim of this work is to give, for practical purposes in routine works, an easy way for obtaining approximated values of E which can be useful for testing, in a very quick way, the stability of the trap levels corresponding to the dosimetric peak in thermoluminescent materials used for environmental, personnel and clinical dosimetry applications. Furthermore, the E values obtained with this method can be used as input data for deconvolution procedure. (Author)

  4. Environmental dosimetry

    International Nuclear Information System (INIS)

    Gold, R.

    1977-01-01

    For more than 60 years, natural radiation has offered broad opportunities for basic research as evidenced by many fundamental discoveries. Within the last decade, however, dramatic changes have occurred in the motivation and direction of this research. The urgent need for economical energy sources entailing acceptably low levels of environmental impact has compelled the applied aspects of our radiation environment to become overriding considerations. It is within this general framework that state-of-the-art environmental dosimetry techniques are reviewed. Although applied motivation and relevance underscores the current milieu for both reactor and environmental dosimetry, a perhaps even more unifying force is the broad similarity of reactor and environmental radiation fields. In this review, a comparison of these two mixed radiation fields is presented stressing the underlying similarities that exist. On this basis, the evolution of a strong inner bond between dosimetry methods for both reactor and environmental radiation fields is described. The existence of this bond will be illustrated using representative examples of observed spectra. Dosimetry methods of particularly high applicability for both of these fields are described. Special emphasis is placed on techniques of high sensitivity and absolute accuracy which are capable of resolving the components of these mixed radiation fields

  5. Clay as Thermoluminescence Dosemeter in diagnostic Radiology ...

    African Journals Online (AJOL)

    This paper reports the investigation of the basic thermoluminescence properties of clay at x-rays in the diagnostic radiology range, including dose monitoring in abdominal radiography. Clay sourced from Calabar, Nigeria, was tested for thermoluminescence response after irradiation at diagnostic radiology doses, including ...

  6. Thermoluminescence spectra measured with a Michelson interferometer

    International Nuclear Information System (INIS)

    Haschberger, P.

    1991-01-01

    A Michelson interferometer was redesigned to prove its capabilities in the measurement of short-lived, low-intensity thermoluminescence spectra. Interferograms are collected during heating up the thermoluminescent probe in a heater plate. A personal computer controls the data acquisition and processes the Fourier transform. As the results show, even a comparatively simple and limited setup leads to relevant and reproducible spectra. (author)

  7. Neutron dosimetry using optically stimulated luminescence

    International Nuclear Information System (INIS)

    Miller, S.D.; Eschbach, P.A.

    1991-06-01

    The addition of thermoluminescent (TL) materials within hydrogenous matrices to detect neutron-induced proton recoils for radiation dosimetry is a well-known concept. Previous attempts to implement this technique have met with limited success, primarily due to the high temperatures required for TL readout and the low melting temperatures of hydrogen-rich plastics. Research in recent years at Pacific Northwest laboratories (PNL) has produced a new Optically Stimulated Luminescence (OSL) technique known as the Cooled Optically Stimulated Luminescence (COSL) that offers, for the first time, the capability of performing extremely sensitive radiation dosimetry at low temperatures. In addition to its extreme sensitivity, the COSL technique offers multiple readout capability, limited fading in a one-year period, and the capability of analyzing single grains within a hydrogenous matrix. 4 refs., 10 figs

  8. An investigation of false positive dosimetry results

    International Nuclear Information System (INIS)

    Lewandowski, M.A.; Davis, S.A.; Goff, T.E.; Wu, C.F.

    1996-01-01

    The Waste Isolation Pilot Plant (WIPP) is a facility designed for the demonstration of the safe disposal of transuranic waste. Currently, the radiation source term is confined to sealed calibration and check sources since WIPP has not received waste for disposal. For several years the WIPP Dosimetry Group has operated a Harshaw Model 8800C reader to analyze Harshaw 8801-7776 thermoluminescent cards (3 TLD-700 and 1 TLD-600) with 8805 holder. The frequency of false positive results for quarterly dosimeter exchanges is higher than desired by the Dosimetry Group management. Initial observations suggested that exposure to intense ambient sunlight may be responsible for the majority of the false positive readings for element 3. A study was designed to investigate the possibility of light leaking through the holder and inducing a signal in element 3. This paper discusses the methods and results obtained, with special emphasis placed on recommendations to reduce the frequency of light-induced false positive readings

  9. Synthesis and thermoluminescent characterization of new matches of LiF:Eu exposed to beta particles

    International Nuclear Information System (INIS)

    Sandoval G, L. M.; Garcia H, A. R.; Bernal, R.; Cruz V, C.; Burruel I, S. E.; Castano, V. M.

    2015-10-01

    Full text: LiF has been and currently is a base material in the preparation of commercial dosimeters due to its characteristics and dosimetric properties. Obtain a material that has stable and sensitive characteristics is what is sought in the field of dosimetry. Pellets were manufactured with different concentrations of dopant (EuCl 3 ) ranging between 0.5, 1.0, 1.5% mol, using the coprecipitation method, these pellets were synthesized at 750 degrees C for 5 hours. The concentration of dopant with the best characteristics is 1.5% mol of EuCl 3 . During the thermoluminescent characterization, the pellets were subjected to various doses of beta radiation ranging from 0.5 to 2.5 Gy, yielding glow curves that increase the intensity of the Tl signal with increasing radiation dose. The results also show good reproducibility, with a main peak around 250 degrees C and a low fading of thermoluminescent signal. (Author)

  10. Thermoluminescence of sulfated zircon exposed to gamma radiation; Termoluminiscencia de circonia sulfatada expuesta a radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Rubio, E.; Castano, V.M. [Centro de Fisica Aplicada y Tecnologia Avanzada, UNAM, A.P. 1-1010, 76000 Queretaro (Mexico); Mendoza A, E.; Gonzalez, P.R. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2003-07-01

    In this work, the thermoluminescent (Tl) signal induced by gamma radiation in zirconia and sulfated zirconia samples embedded in Ptfe pellets is reported and discussed. In this case, samples were obtained through sol-gel method using zirconium n-propoxide and H{sub 2}SO{sub 4} as precursors, and later were subjected to thermal treatment at 600 C to obtain, the tetragonal phase accordingly to X-ray diffraction analysis. Experimental results show that the thermoluminescent glow peak depends on both, the crystalline structure and sulfate concentration. Two maximum peaks were observed located at 147 C and 274 C arising from the electronic transitions. Tl response as a function of the absorbed dose shows a linear increase for a wide of range exposure as well as good stability in time. The high sensitivity, dose linearity and signal stability of this material open the potential possibility to be used for the dosimetry applications. (Author)

  11. 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)

  12. Thermoluminescence glow curve of CaZrO3 phosphor doped with Eu3+

    International Nuclear Information System (INIS)

    Tiwari, Neha; Kuraria, R.K.; Kuraria, S.R.

    2014-01-01

    Behaviour displayed by thermoluminescence analysis of Eu 3+ doped CaZrO 3 phosphor prepared by combustion synthesis technique. The sample was synthesized by combustion method because it is less time taking method as well as low temperature synthesis. For the thermoluminescence study the prepared sample irradiated by UV lamp the wavelength is 254 nm. Every time 2 mg of sample used for TL record at fixed heating rate 5℃ s -1 , sample shows well resolved higher temperature peak at 273℃. The high temperature peak shows more stability and less fading in prepared phosphor which is suitable for TL dosimetry. Also the variation with UV dose (5 to 30 min) shows sublinear response with dose

  13. Thermoluminescence dating of pleistocene sediments

    International Nuclear Information System (INIS)

    Poupeau, G.; Souza, J.H.; Rivera, A.

    1984-01-01

    After a short introduction on recent trends in quaternary geochronology, this article focuses on the thermoluminescence dating of sediments, whose principles and present limits and prospects are discussed. Results are presented for the TL behaviour of sands from various geological contexts in Brazil. They show that the coarse (approx. 100-200μm) quartz fraction of coastal and intra continental, eolian and fluvial-type deposits, might be datable by TL from the upper Holocene to at least the basis of the upper Pleistocene, with a precision of + - 10-15%. (Author) [pt

  14. Thermoluminescence dating of pleistocene sediments

    International Nuclear Information System (INIS)

    Poupeau, G.; Souza, J.H.

    1984-01-01

    After a short introduction on recent trends in quaternary geochronology, this article focuses on the thermoluminescence (TL) dating of sediments, whose principles, present limits and prospects are discussed. Results are presented for TL behavior of sands from various geological contexts in Brazil. They show that the coarse (approx. 100-200 μm) quartz fraction of coastal and intracontinental, eolian and fluvial - type deposits, might be datable by TL from the upper Holocene to at least the base of the upper Pleistocene, with a precision of +- 10-15%. (Author) [pt

  15. Thermoluminescence study of lithium fluorides

    CERN Document Server

    Abu-Alazm, S M

    2003-01-01

    The spectrum of the light emitted during thermoluminescence (TL) from irradiated lif sample with different doses of Xe, Kr and electrons have been studied. The results show a main peak for all samples irradiated and unirradiated at temperature about 200 degree C. Morcever when the reaches to the value 5x10 sup 1 1 ion/cm sup 2 a new two bands begin to appear in case of Xe and Kr ion irradiation. The TL spectra under Kr and Xe ion irradiation similar at the same dose. However, the spectra under electron irradiation were found to be rather different than under heavy ions irradiation.

  16. Models and methods in thermoluminescence

    International Nuclear Information System (INIS)

    Furetta, C.

    2005-01-01

    This work contains a conference that was treated about the principles of the luminescence phenomena, the mathematical treatment concerning the thermoluminescent emission of light as well as the Randall-Wilkins model, the Garlick-Gibson model, the Adirovitch model, the May-Partridge model, the Braunlich-Scharman model, the mixed first and second order kinetics, the methods for evaluating the kinetics parameters such as the initial rise method, the various heating rates method, the isothermal decay method and those methods based on the analysis of the glow curve shape. (Author)

  17. Models and methods in thermoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Furetta, C. [ICN, UNAM, A.P. 70-543, Mexico D.F. (Mexico)

    2005-07-01

    This work contains a conference that was treated about the principles of the luminescence phenomena, the mathematical treatment concerning the thermoluminescent emission of light as well as the Randall-Wilkins model, the Garlick-Gibson model, the Adirovitch model, the May-Partridge model, the Braunlich-Scharman model, the mixed first and second order kinetics, the methods for evaluating the kinetics parameters such as the initial rise method, the various heating rates method, the isothermal decay method and those methods based on the analysis of the glow curve shape. (Author)

  18. New 2-D dosimetric technique for radiotherapy based on planar thermoluminescent detectors

    International Nuclear Information System (INIS)

    Olko, P.; Marczewska, B.; Czopyk, L.; Czermak, M. A.; Klosowski, M.; Waligorski, M. P. R.

    2006-01-01

    At the Inst. of Nuclear Physics of the Polish Academy of Sciences (IFJ) in Krakow, a two-dimensional (2-D) thermoluminescence (TL) dosimetry system was developed within the MAESTRO (Methods and Advanced Equipment for Simulation and Treatment in Radio-Oncology) 6 Framework Programme and tested by evaluating 2-D dose distributions around radioactive sources. A thermoluminescent detector (TLD) foil was developed, of thickness 0.3 mm and diameter 60 mm, containing a mixture of highly sensitive LiF:Mg,Cu,P powder and Ethylene Tetrafluoroethylene (ETFE) polymer. Foil detectors were irradiated with 226 Ra brachytherapy sources and a 90 Sr/ 90 Y source. 2-D dose distributions were evaluated using a prototype planar (diameter 60 mm) reader, equipped with a 12 bit Charge Coupled Devices (CCD) PCO AG camera, with a resolution of 640 x 480 pixels. The new detectors, showing a spatial resolution better than 0.5 mm and a measurable dose range typical for radiotherapy, can find many applications in clinical dosimetry. Another technology applicable to clinical dosimetry, also developed at IFJ, is the Si microstrip detector of size 95 x 95 mm 2 , which may be used to evaluate the dose distribution with a spatial resolution of 120 μm along one direction, in real-time mode. The microstrip and TLD technology will be further improved, especially to develop detectors of larger area, and to make them applicable to some advanced radiotherapy modalities, such as intensity modulated radiotherapy (IMRT) or proton radiotherapy. (authors)

  19. Main Achievements 2003-2004 - Interdisciplinary Research - Radiation detection methods for health, earth and environmental sciences - Thermoluminescence (TL) detectors

    International Nuclear Information System (INIS)

    2005-01-01

    The IFJ has over 35 years of experience in the development, production and application of new types of thermoluminescence (TL) detectors, particularly LiF:Mg,Ti and LiF:Mg,Cu,P. Over 600,000 LiF detectors produced at the IFJ PAN are routinely applied in dosimetry services and hospitals in 30 countries. The current research in the field of thermoluminescence concentrates in space dosimetry and novel 2-dimensional detectors for medical applications. The space project (named Matroshka), organized by the European Space Agency, is one of the most ambitious dosimetry experiments in space. In February 2004 an anatomical model of the human body (a humanoid phantom), equipped with over 3500 dedicated thermoluminescent detectors (TLD), developed and produced at IFJ and tested at the Chiba heavy ion accelerator in Japan, was installed outside the International Space Station (ISS) to determine the cosmic radiation doses absorbed in human organs, which would be experienced by astronauts in open space. The phantom will remain in space for one year, after which the detectors will be returned to the IFJ for analysis

  20. Comparative study of thermoluminescent, radiophotoluminescent and photographic dosemeters

    International Nuclear Information System (INIS)

    Deus, S.F.

    1976-01-01

    Comparison was made between the response of three differents dosimetric systems, namely, photographic, thermoluminescent (TL) and radiophotoluminescent (RPL). The comparison was divided in two parts. The first was carried out in known radiation conditions (exposure, normal incidence, energy) and under controlled environment (approximately 27 0 C temperature, approximately 70% relative humidity). Under these conditions, the response as a function of exposure and energy, the relation of the linearity to the energy, the lowest detectable exposure, and the reproducibility, were studied. The response against esposure at 37 KeVef and at 1 MeV was found to be linear in the region of interest to routine personnel dosimetry for all dosimeters except for the filmes. In the second part, the relative response of the dosimeters was verified under the uncontrolled conditions of personnel dosimetry. As the CaSO 4 :Dy is the most sensitive dosimeter, comparison was made using this dosimeter as the standard, in which case one finds that 20 of 29 TLD-100 dosimeters give the same reading within 30%, 13 of 29 RPL dosimeters agree within 30%, and only 3 of 29 films fall within 30% [pt

  1. Thermoluminescence as a dating method applied to the Morocco Neolithic

    International Nuclear Information System (INIS)

    Ousmoi, M.

    1989-09-01

    Thermoluminescence is an absolute dating method which is well adapted to the study of burnt clays and so of the prehistoric ceramics belonging to the Neolithic period. The purpose of this study is to establish a first absolute chronology of the septentrional morocco Neolithic between 3000 and 7000 years before us and some improvements of the TL dating. The first part of the thesis contains some hypothesis about the morocco Neolithic and some problems to solve. Then we study the TL dating method along with new process to ameliorate the quality of the results like the shift of quartz TL peaks or the crushing of samples. The methods which were employed using 24 samples belonging to various civilisations are: the quartz inclusion method and the fine grain technique. For the dosimetry, several methods were used: determination of the K 2 O contents, alpha counting, site dosimetry using TL dosimeters and a scintillation counter. The results which were found bring some interesting answers to the archeologic question and ameliorate the chronologic schema of the Northern morocco Neolithic: development of the old cardial Neolithic in the North, and perhaps in the center of Morocco (the region of Rabat), between 5500 and 7000 before us. Development of the recent middle Neolithic around 4000-5000 before us, with a protocampaniforme (Skhirat), little older than the campaniforme recognized in the south of Spain. Development of the bronze age around 2000-4000 before us [fr

  2. Systematic development of new thermoluminescence and optically stimulated luminescence materials

    Energy Technology Data Exchange (ETDEWEB)

    Yukihara, E.G., E-mail: eduardo.yukihara@okstate.edu [Physics Department, 145 Physical Sciences II, Oklahoma State University, Stillwater, OK 74078 (United States); Milliken, E.D.; Oliveira, L.C. [Physics Department, 145 Physical Sciences II, Oklahoma State University, Stillwater, OK 74078 (United States); Orante-Barron, V.R. [Departamento de Investigacion en Polimeros y Materiales, Universidad de Sonora, Hermosillo, Sonora 83000, Mexico (Mexico); Jacobsohn, L.G. [Center for Optical Materials Science and Engineering Technologies (COMSET), and School of Materials Science and Engineering, Clemson University, Clemson, SC (United States); Blair, M.W. [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2013-01-15

    This paper presents an overview of a systematic study to develop new thermoluminescence (TL) and optically stimulated luminescence (OSL) materials using solution combustion synthesis (SCS) for applications such as personal OSL dosimetry, 2D dose mapping, and temperature sensing. A discussion on the material requirements for these applications is included. We present X-ray diffraction (XRD) data on single phase materials obtained with SCS, as well as radioluminescence (RL), TL and OSL data of lanthanide-doped materials. The results demonstrate the possibility of producing TL and OSL materials with sensitivity similar to or approaching those of commercial TL and OSL materials used in dosimetry (e.g., LiF:Mg,Ti and Al{sub 2}O{sub 3}:C) using SCS. The results also show that the luminescence properties can be improved by Li co-doping and annealing. The presence of an atypical TL background and anomalous fading are discussed and deserve attention in future investigations. We hope that these preliminary results on the use of SCS for production of TL and OSL materials are helpful to guide future efforts towards the development of new luminescence materials for different applications. - Highlights: Black-Right-Pointing-Pointer TL and OSL material produced with sensitivity similar to commercial materials. Black-Right-Pointing-Pointer Luminescence properties improved by Li co-doping and annealing. Black-Right-Pointing-Pointer The presence of atypical TL background and anomalous fading observed.

  3. γ radiation thermoluminescence performance of HFCVD diamond films

    International Nuclear Information System (INIS)

    Gastelum, S.; Cruz-Zaragoza, E.; Melendrez, R.; Chernov, V.; Barboza-Flores, M.

    2006-01-01

    Polycrystalline chemically vapor deposited (CVD) diamond films have been proposed as detectors and dosimeters of ionizing radiation with prospective applications in high-energy photon dosimetry applications. We present a comparison study on the thermoluminescence (TL) properties of two diamond film samples grown by the hot filament CVD method having thickness of 180 and 500 μm and exposed to γ radiation in the 1-300 Gy dose range. The 180 μm thick sample deposited on silicon substrate displayed a TL glow curve peaked at 145 deg. C. The 500 μm, which was a free standing sample, exhibited higher intensity and a well defined first order kinetics TL glow peak around 289 deg. C. Both diamond samples showed a linear dose behavior in the 1-50 Gy range and sublinear behavior for higher doses. The 180 and 500 μm samples presented about 80% and 30% TL losses in a 24 h period, respectively, with both samples showing excellent TL reproducibility. The results indicate that the 500 μm CVD diamond film exhibited a good TL behavior adequate for γ radiation dosimetry

  4. Persistent luminescence and thermoluminescence of UV/VIS -irradiated SrAl2O4: Eu2+, Dy3+ phosphor

    International Nuclear Information System (INIS)

    Pereyda-Pierre, C.; Meléndrez, R.; García, R.; Pedroza-Montero, M.; Barboza-Flores, M.

    2011-01-01

    The persistent luminescence and thermoluminescence properties of SrAl 2 O 4 : Eu 2+ , Dy 3+ phosphors excited with UV–VIS light in the 200–500 nm region were investigated. The thermoluminescence glow curve was found to be composed of peaks around 70, 125 and 245 °C. The persistent luminescence and thermoluminescence excitation spectra exhibited a broad band around 300–500 nm centered at 400 and 420 nm respectively. A linear behavior of the integrated thermoluminescence intensity and persistent luminescence versus irradiation time was found for the first 60 s. The charge detrapping from the 70 °C trapping levels was the major contributor to the observed persistent luminescence at room temperature. The SrAl 2 O 4 : Eu 2+ , Dy 3+ phosphors have suitable properties to be applied as storage and persistent luminescence UV–VIS irradiation dose phosphor. -- Highlights: ► SrAl 2 O 4 :Eu 2+ , Dy 3+ persistent luminescence and thermoluminescence was measured. ► The phosphor was irradiated with UV–VIS photons in the 200–500 nm wavelength range. ► SrAl 2 O 4 :Eu 2+ , Dy 3+ behaves adequately as persistent and storage UV–VIS dosimeter. ► The persistent luminescence dosimetry does not require heat or light stimulation.

  5. Measurement of the dose by dispersed radiation in a lineal accelerator using thermoluminescent dosimeters of CaSO4:Dy

    International Nuclear Information System (INIS)

    Chavez C, N.; Torijano, E.; Azorin, J.; Herrera, A.

    2014-08-01

    The thermoluminescence (Tl) is based on the principle of the luminescent in a material when is heated below their incandescence temperature. Is a technique very used in dosimetry that is based on the property that have most of the crystalline materials regarding the storage of the energy that they absorb when are exposed to the ionizing radiations. When this material has been irradiated previously, the radioactive energy that contains is liberated in form of light. In general, the principles that govern the thermoluminescence are in essence the same of those responsible for all the luminescent processes and, this way, the thermoluminescence is one of the processes that are part of the luminescence phenomenon. For this work, the dispersed radiation was measured in the therapy area of the lineal accelerator of medical use type Elekta, using thermoluminescent dosimeters of CaSO 4 :Dy + Ptfe developed and elaborated in the Universidad Autonoma Metropolitana, Unidad Iztapalapa. With the dosimeters already characterized and calibrated, we proceeded to measure the dispersed radiation being a patient in treatment. The results showed values for the dispersed radiation the order of a third of the dose received by the patient on the treatment table at 30 cm of the direct beam and the order of a hundredth in the control area (4 m of the direct beam, approximately). The conclusion is that the thermoluminescent dosimeters of CaSO 4 : Dy + Ptfe are appropriate to measure dispersed radiation dose in radiotherapy. (author)

  6. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1981-01-01

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments

  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. Quality control and quality assurance philosophy introduced in national personnel dosimetry service

    International Nuclear Information System (INIS)

    Trousil, J.; Zelenka, Z.; Kvasnicka, O.

    2008-01-01

    There in National Personnel Dosimetry Service (NPDS) the implementation of the control system to guarantee the credibility of the measured personal dose equivalents results was given on the basis of the international recommendations published by the European Commission and the IAEA and in particular of the decree of the SUJB No. 132/2008 Coll. The quality control and the quality assurance are carried out in all three personal dosimetry services introduced in NPDS: in the film badge, thermoluminescent (TL) and neutron dosimetry. (authors)

  9. Study of thermoluminescence response of purple to violet amethyst quartz from Balikesir, Turkey

    International Nuclear Information System (INIS)

    Nur, N.; Yeğingil, Z.; Topaksu, M.; Kurt, K.; Doğan, T.; Sarıgül, N.; Yüksel, M.; Altunal, V.; Özdemir, A.; Güçkan, V.; Günay, I.

    2015-01-01

    Highlights: • We reported on dosimetric characterisation of natural amethyst quartz specimens from Turkey, using TL technique. • The thermoluminescence characterisation tests were performed under the beta radiation exposure. • The IT peaks ∼230 °C show superlinear dose response behavior (g(D) > 1) between 1 Gy and 5 kGy. The HT peaks ∼300 °C show linear behavior (g(D) = 1) at low dose levels (1 < D < 20 Gy) and superlinearity (g(D) > 1) between 20 Gy < D < 2 kGy. • Deviations were determined for recycling measurements for various dose values of 0.1, 0.5, 0.8 and 1 kGy. • Amethyst quartz has great potential to be investigated for dosimetry purpose. - Abstract: In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir–Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450 °C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by 90 Sr/ 90 Y beta particles. Isothermal annealing before and after irradiation was found to have a definite effect upon the TL glow curve of amethyst crystal powder. The same sample varied in sensitivity depending upon its previous thermal and radiation history. The peak heights of the glow peaks were examined with respect to dose response at dose levels between 1 Gy and 5 kGy. The intermediate temperature (IT) and high temperature (HT) peaks of 230 °C and 300 °C, respectively, exhibit dose

  10. Study of thermoluminescence response of purple to violet amethyst quartz from Balikesir, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Nur, N., E-mail: nnur@adiyaman.edu.tr [Adiyaman University, Engineering Faculty, Department of Electrical and Electronic Engineering, 02040 Adiyaman (Turkey); Yeğingil, Z.; Topaksu, M. [Cukurova University, Art and Sciences Faculty, Physics Department, 01330 Adana (Turkey); Kurt, K. [University of Mersin, Science and Art Faculty, Physics Department, 33343 Mersin (Turkey); Doğan, T. [Cukurova University, Vocational School of Imamoglu, Department of Technical Programs, 01700 Adana (Turkey); Sarıgül, N. [Institute of Nuclear Science, Hacettepe University, 06532 Ankara (Turkey); Yüksel, M.; Altunal, V.; Özdemir, A.; Güçkan, V. [Cukurova University, Art and Sciences Faculty, Physics Department, 01330 Adana (Turkey); Günay, I. [Cukurova University, Medicine Faculty, Biophysics Department, Adana (Turkey)

    2015-09-01

    Highlights: • We reported on dosimetric characterisation of natural amethyst quartz specimens from Turkey, using TL technique. • The thermoluminescence characterisation tests were performed under the beta radiation exposure. • The IT peaks ∼230 °C show superlinear dose response behavior (g(D) > 1) between 1 Gy and 5 kGy. The HT peaks ∼300 °C show linear behavior (g(D) = 1) at low dose levels (1 < D < 20 Gy) and superlinearity (g(D) > 1) between 20 Gy < D < 2 kGy. • Deviations were determined for recycling measurements for various dose values of 0.1, 0.5, 0.8 and 1 kGy. • Amethyst quartz has great potential to be investigated for dosimetry purpose. - Abstract: In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir–Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450 °C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by {sup 90}Sr/{sup 90}Y beta particles. Isothermal annealing before and after irradiation was found to have a definite effect upon the TL glow curve of amethyst crystal powder. The same sample varied in sensitivity depending upon its previous thermal and radiation history. The peak heights of the glow peaks were examined with respect to dose response at dose levels between 1 Gy and 5 kGy. The intermediate temperature (IT) and high temperature (HT) peaks of 230 °C and 300 °C, respectively

  11. Thermoluminescent analyses of mean photon energy of a field

    Energy Technology Data Exchange (ETDEWEB)

    Cavalieri, T. A.; De Paiva, F.; Fonseca, G.; Dalledone S, P. de T.; Yoriyaz, H., E-mail: tassio.cavalieri@usp.br [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2014-08-15

    Nowadays a common method of dosimetry is utilize the thermoluminescent dosimetry (TLD) of LiF, where for pure gamma field is typically used the LiF or CaF{sub 2} TLDs and for mixed neutron and gamma field dosimetry is used the pair TLD-600/TLD-700. The difference between these three LiF TLDs is the amount of isotope {sup 6}Li in their composition. The isotope {sup 6}Li has a great cross section for thermal neutrons, making the TLD-600 sensitive to thermal neutrons beyond the radiation gamma. Whereas the TLD-700 is considered sensitive only for radiation gamma. Some studies showed an energetic dependence of these TLDs for gammas rays. So the goal of this work was study these energetic dependence of TLDs from the angular coefficient of their response versus dose calibration curves when they were irradiated in four fields with photons of different energies: 43 keV, 662 keV, 1.2 MeV, 3 MeV. In order to create the calibration curves TLD, it was performed three irradiations with distinct exposure times for each photon energy. These studies showed a different angular coefficient to each curve; demonstrate the energetic dependence of these TLDs. By simulation with Monte Carlo based code, MCNP-5, it was observed the deposited photon dose due to different photons energies. From these simulations, it was also possible to observe a difference of dose deposition in TLDs when they were exposed to the same dose provided from different photons energies. These work showed the previously study of photon energetic dependence of LiF TLDs. (Author)

  12. Dosimetric behavior of thermoluminescent dosimeters at low doses in diagnostic radiology

    International Nuclear Information System (INIS)

    Del Sol F, S.; Garcia S, R.; Guzman M, J.; Sanchez G, D.; Rivera M, T.; Ramirez R, G.; Gaona, E.

    2015-10-01

    Thermoluminescent (Tl) characteristics of TLD-100, LiF:Mg,Cu,P, and CaSO 4 : Dy the under homogeneous field of X-ray beams of diagnostic irradiation and its verification using thermoluminescent dosimetry is presented. The irradiations were performed utilizing an X-ray beam generated by a Radiology Mexican Company: MRH-II E GMX 325-AF SBV-1 model, with Rotating Anode X-Ray Tube installed in the Hospital Juarez Norte de Mexico in Mexico City. Different thermoluminescent characteristics of dosimetric material were studied, such as, batch homogeneity, Tl glow curve, Tl response as a function of X-ray dose, reproducibility and fading. Materials were calibrated in terms of absorbed dose to the standard calibration distance and positioned in a generic Phantom was used. Dose verification and comparison with the measurements made with that obtained by TLD-100 were analyzed. Preliminary results indicate the dosimetric peak appears at 243, 236 and 277 ± 5 degrees C respectively, these peaks are in agreement with that reported in the literature. Tl glow curve as a function of X-ray dose showed a linearity in the range from 1.76 mGy up to 14.70 mGy for all materials. Fading for a period of one month at room temperature showed low fading LiF:Mg,Cu,P, medium and high for TLD-100 and CaSO 4 : Dy. The results suggest that the three materials are suitable for measurements at low doses in radiodiagnostic, however, for its dosimetric characteristics are most effective for individual applications: personal dosimetry and monitors limb (LiF:Mg,Cu,P), clinical dosimetry and environmental (TLD-100 and CaSO 4 : Dy). (Author)

  13. Hematological dosimetry

    International Nuclear Information System (INIS)

    Fluery-Herard, A.

    1991-01-01

    The principles of hematological dosimetry after acute or protracted whole-body irradiation are reviewed. In both cases, over-exposure is never homogeneous and the clinical consequences, viz medullary aplasia, are directly associated with the mean absorbed dose and the seriousness and location of the overexposure. The main hematological data required to assess the seriousness of exposure are the following: repeated blood analysis, blood precursor cultures, as indicators of whole-body exposure; bone marrow puncture, medullary precursor cultures and medullary scintigraphy as indicators of the importance of a local over-exposure and capacity for spontaneous repair. These paraclinical investigations, which are essential for diagnosis and dosimetry, are also used for surveillance and for the main therapeutic issues [fr

  14. Study and development of radiothermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Portal, Guy.

    1978-11-01

    After briefly reviewing bibliography concerning the mechanism of radiothermoluminescence and its use in dosimetry, we have concentrated on studies of three thermoluminescent products: magnesium activated lithium fluoride, alumina and calcium sulfate activated with either dysprosium or thulium. In particular, the preparation and singular properties of a new type of lithium fluoride stabilised with sodium, created especially for dosimetric purposes, is described. The physical characteristics of these three products, their emission spectra and their trap parameters, have been studied and we have analysed, both theoretically and experimentally, their dosimetric properties, paying particular attention to their relative chromatic sensitivity to photons and neutrons. It is shown that alumina exhibits an exceptional neutron thermoluminescent yield which points to a potential interest in this material which is little used to date. The deep trapping levels of these products have been studied and some levels found appearing at temperatures above 600 0 C: these can be used for radiation dosimetry in enclosures at temperatures between 400 and 450 0 C. Finally, a brief outline of radiothermoluminescent applications of these products in the radioprotection, medical, biological, archeological and industrial fields is presented [fr

  15. Method for detecting radiation dose utilizing thermoluminescent material

    International Nuclear Information System (INIS)

    Miller, S.D.; McDonald, J.C.; Eichner, F.N.; Durham, J.S.

    1992-01-01

    The amount of ionizing radiation to which a thermoluminescent material has been exposed is determined by first cooling the thermoluminescent material and then optically stimulating the thermoluminescent material by exposure to light. Visible light emitted by the thermoluminescent material as it is allowed to warm up to room temperature is detected and counted. The thermoluminescent material may be annealed by exposure to ultraviolet light. 5 figs

  16. A contribution to thermoluminescence dosemeter system optimisation applied to environmental monitoring around nuclear power plants

    International Nuclear Information System (INIS)

    Dies, X.; Ortega, X.; Rosell, J.

    1990-01-01

    The factors that constitute a thermoluminescence dosimetric system have been studied and optimised, with the intention of defining strategies for improving precision and accuracy of TL dosimetry systems for environmental monitoring. An optimisation technique based on fractional factorial designs permitted a reduction in the number of necessary experiments and clarified interactions between various factors. The model for fading over time showed that TL response in LiF:Mg,Ti dosemeters was independent of time between irradiation and readout, and this was applied to fading corrections in nuclear power plant environmental monitoring. (author)

  17. Thermoluminescence of rare earth doped BaSO/sub 4/ phosphors and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, J.S.; Varadharajan, G. (Bhabha Atomic Research Centre, Bombay (India). Div. of Radiological Protection)

    1982-03-01

    Thermoluminescence of synthetic BaSO/sub 4/ samples individually doped with Y, La, Ce, Pr, Nd, Sm, Eu, Tb, Dy and Tm has been studied after ..gamma..- and microwave irradiations. BaSO/sub 4/:Eu has the highest response for ..gamma..-radiation while BaSO/sub 4/:Tb exhibits highest reduction in its ..gamma..-induced TL after exposure to microwave radiation (2425 +- 25 MHz). The reduction depends on the microwave radiant exposure and is independent of the irradiance level in the range 25-200 mW . cm/sup -2/ and hence can be useful for microwave dosimetry.

  18. Factors controlling the thermoluminescence spectra of rare earth doped calcium fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y., E-mail: wyfemail@gmail.com [School of Science, China University of Geosciences, Beijing 100083 (China); Zhao, Y. [School of Science, China University of Geosciences, Beijing 100083 (China); White, D. [Barnsley Hospital NHS Foundation Trust, Gawber Road, Barnsley S75 2EP (United Kingdom); Finch, A.A. [Department of Earth & Environmental Sciences, University of St Andrews, Fife KY16 9AL (United Kingdom); Townsend, P.D. [Physics Building, University of Sussex, Brighton BN1 9QH (United Kingdom)

    2017-04-15

    Thermoluminescence spectra of rare earth doped calcium fluoride samples, both powder and single crystal, were recorded over the temperature range from 25 K to 673 K. Although some broad band features exist, the spectra are dominated by the rare earth line transitions. The glow peak temperatures are slightly sensitive both to the ionic size of the dopants and the dopant concentration. By contrast, very considerable differences are generated by heat treatments, such as annealing followed by either fast or slow cooling. Comments are included on the reasons for such sensitivity in terms of association of dopant and intrinsic defect sites and why the results of dosimetry powder differ from those from single crystals.

  19. Investigation about the thermal features of the ovens used for thermoluminescence

    International Nuclear Information System (INIS)

    Scarpa, G.; Caporali, C.; Moscati, M.

    1991-02-01

    The present paper reports the results of an investigation carried out by the PAS-FIBI-DOSIBIO laboratory (ENEA, Casaccia, Roma) about the thermal features of the ovens used for annealing treatments of TL dosemeters. A total number of 45 commercial ovens and muffle furnaces were studied. belonging to 24 Italian Health Physics laboratories. The investigation has shown that the majority of the ovens do not possess a degree of accuracy, stability, uniformity and reproducibility suitable for their use in the field of thermoluminescence dosimetry. Practical suggestions are also given in order to reduce the effects of some of the negative characteristics found in most ovens. (author)

  20. State of the art of solid state dosimetry

    International Nuclear Information System (INIS)

    Souza, Susana O.; Yamamoto, Takayoshi; D'Errico, Francesco

    2014-01-01

    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

  1. Type tests to the automatic thermoluminescent dosimetry system acquired by the CPHR for personal dosimetry

    International Nuclear Information System (INIS)

    Molina P, D.; Pernas S, R.; Martinez G, A.

    2006-01-01

    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)

  2. Type tests to the automatic system of thermoluminescent dosimetry acquired by the CPHR for personnel dosimetry

    International Nuclear Information System (INIS)

    Molina P, D.; Pernas S, R.

    2005-01-01

    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)

  3. Clinical application of in vivo dosimetry for external telecobalt machine

    International Nuclear Information System (INIS)

    Mohammed, H. H. M.

    2011-01-01

    In external beam radiotherapy quality assurance is carried out on the individual components of treatment chain. The patient simulating device, planning system and treatment machine are tested regularly according to set protocols developed by national and international organizations. Even thought these individual systems are not tested for errors which can be made in the transfer between the systems. The best quality assurance for the treatment planning chain. In vivo dosimetry is used as a quality assurance tool for verifying dosimetry as either the entrance or exit surface of the patient undergoing external beam radiotherapy. It is a proven reliable method of checking overall treatment accuracy, allowing verification of dosimetry and dose calculation as well as patient treatment setup. Accurate in vivo dosimetry is carried out if diodes and thermoluminescence dosimeters (TLDs). the main detector types in use for in vivo dosimetry, are carefully calibrated and the factors influencing their sensitivity are taken into account. The aim of this study was to verify the response of TLDs type (LiF: Mg, Cu, p) use in radiotherapy, to establish calibration procedure for TLDs and to evaluate entrance dose obtained by the treatment planning system with measured dose using thermoluminescence detectors. Calibration of TLDs was done using Cobalt-60 teletherapy machine, linearity and calibration factors were determined. Measurements were performed in random phantom for breast irradiation (for the breast irradiation ( For the breast irradiation technique considered, wedge field was used). All TLDs were processed and analyzed at RICK. In vivo dosimetry represents a technique that has been widely employed to evaluate the dose to the patient mainly in radiotherapy. Thermoluminescent dosimeters are considered the gold stander for in vivo dosimetry and do not require cables for measurements which makes them ideal for mail based studies and have no dose rate or temperature dependence

  4. Thermoluminescent Signals Caused by Disturbing Effects

    International Nuclear Information System (INIS)

    German, U.; Weinstein, M.; Ben-Shachar, B.

    1999-01-01

    One of the major sources of uncertainty in the measurement of low radiation doses by means of thermoluminescence dosemeters is the presence of disturbing thermoluminescence signals, especially luminescence caused by visible light, and by materials attached to the heated areas. Glow curves of thermoluminescence dosemeters contain useful information that can improve the accuracy and the reliability of the thermoluminescent measurements. The influence of the various disturbing effects can be recognised in the shape of the glow curves and can sometimes be separated from the exposure. Some examples are presented of signals arising from the two disturbing effects mentioned above, the signal contributed by Teflon used in the TLD-100 cards of Bicron/Harshaw and some abnormal glow curves due to dirt attached to the cards. Subtraction of the contributions due to these effects is suggested to obtain the net exposure signal. (author)

  5. Dose-rate dependence of thermoluminescence response

    International Nuclear Information System (INIS)

    McKeever, S.W.S.; Chen, R.; Groom, P.J.; Durrani, S.A.

    1980-01-01

    The previously observed dose-rate effect of thermoluminescence in quartz at high dose-rates is given at theoretical formulation. Computer calculations simulating the experimental conditions yield similar results to the experimental ones. (orig.)

  6. RCT: Module 2.04, Dosimetry, Course 8769

    Energy Technology Data Exchange (ETDEWEB)

    Hillmer, Kurt T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-11

    This course will introduce the types of instruments used to measure external and internal radiation to people. Dosimetry is the quantitative assessment of radiation received by the human body. Several types of dosimeters are used worldwide. This information is valuable to all radiological control personnel because dosimeters are the only direct method to measure and document personnel radiation exposure and ensure regulatory compliance with applicable limits. This course will cover dosimetry terms, Department of Energy (DOE) limits, Los Alamos National Laboratory (LANL) administrative guidelines, thermoluminescent dosimeters (TLDs), LANL dosimetry, and bioassay assessment methods. This course will prepare the student with the skills necessary for radiological control technician (RCT) qualification by passing quizzes, tests, and the RCT Comprehensive Phase 1, Unit 2 Examination (TEST 27566) and providing in-thefield skills.

  7. Positional glow curve simulation for thermoluminescent detector (TLD) system design

    International Nuclear Information System (INIS)

    Branch, C.J.; Kearfott, K.J.

    1999-01-01

    Multi- and thin element dosimeters, variable heating rate schemes, and glow-curve analysis have been employed to improve environmental and personnel dosimetry using thermoluminescent detectors (TLDs). Detailed analysis of the effects of errors and optimization of techniques would be highly desirable. However, an understanding of the relationship between TL light production, light attenuation, and precise heating schemes is made difficult because of experimental challenges involved in measuring positional TL light production and temperature variations as a function of time. This work reports the development of a general-purpose computer code, thermoluminescent detector simulator, TLD-SIM, to simulate the heating of any TLD type using a variety of conventional and experimental heating methods including pulsed focused or unfocused lasers with Gaussian or uniform cross sections, planchet, hot gas, hot finger, optical, infrared, or electrical heating. TLD-SIM has been used to study the impact on the TL light production of varying the input parameters which include: detector composition, heat capacity, heat conductivity, physical size, and density; trapped electron density, the frequency factor of oscillation of electrons in the traps, and trap-conduction band potential energy difference; heating scheme source terms and heat transfer boundary conditions; and TL light scatter and attenuation coefficients. Temperature profiles and glow curves as a function of position time, as well as the corresponding temporally and/or spatially integrated glow values, may be plotted while varying any of the input parameters. Examples illustrating TLD system functions, including glow curve variability, will be presented. The flexible capabilities of TLD-SIM promises to enable improved TLD system design

  8. Thermoluminescence of LaAlO3

    International Nuclear Information System (INIS)

    Morales H, A.; Zarate M, J.; Rivera M, T.; Azorin N, J.

    2015-10-01

    In this paper the thermoluminescent properties of doped lanthanum aluminate (LaAlO 3 ) with dysprosium ion (Dy) were studied. The thermoluminescence characteristics in the samples were obtained using an ultraviolet radiation of 220 nm. The LaAlO 3 :Dy samples were prepared by the modified Pechini method (Spray Dryer). The structural and morphological characterization was obtained by X-ray diffraction (XRD) and scanning electron microscopy (Sem) techniques respectively. The size particle composing the agglomerate was determined by Sem, agglomerated particles composed size of 2μm were observed. The thermoluminescence response of LaAlO 3 :Dy was compared with that obtained with the undoped sample. Thermoluminescence brightness curves of LaAlO 3 :Dy showed a peak centered at 185 grades C. Sensitivity of doped sample was greater, about 100 times compared with the undoped sample. Thermoluminescence response in function of the wavelength showed a maximum at 220 nm. Also the fading in thermoluminescence response was studied. (Author)

  9. Personnel-dosimetry intercomparison studies at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Swaja, R.E.; Sims, C.S.

    1982-01-01

    Since 1974, seven annual personnel dosimetry intercomparison studies have been conducted at the Oak Ridge National Laboratory using the Health Physics Reactor. These studies have produced more than 2000 measurements by 72 participating organizations of neutron and gamma dose equivalents between 0.1 to 15.0 mSv in six mixed radiation fields. The relative performance of three basic types of personnel neutron dosimeters (nuclear emulsion film, thermoluminescent, and track-etch) and two basic types of gamma dosimeters (film and thermoluminescent) was assessed based on experimental results obtained during the seven intercomparisons

  10. Dosimertry characteristics and performance comparisons: Environmental radiophotoluminescent glass dosemeters versus thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Lee, J.H.; Lin, M.S.; Hsu, S.M.; Chen, I.J.; Chen, W.L.; Wang, C.F.

    2009-01-01

    This paper describes the dosimetry characteristic comparison of environmental radiophotoluminescent glass dosemeter (RPLGD) and thermoluminescent dosemeter (TLD) systems employed at the Institute of Nuclear Energy Research (INER, Taiwan). The luminescence centers of TLD disappeared by reading process, and repetition of measurement is impossible. RPLGDs can be repeatedly read and keep the luminescence centers for a long time. The RPLGD fading is about 1% within 30 days after being exposed to ionizing radiation. Environmental cumulative doses measured by a RPLGD and a TLD were compared at the same monitoring points of INER during two years. The sensitivity of TLD decreased with gradual loss due to fading at higher temperatures. The difference between results obtained by RPLGD and TLD is discussed mainly with respect to the dependence on the ambient temperature. In addition, this research also refers to the American National Standard Institute (ANSI) Draft Standard N13.29 (1996) to organize the environmental dosimetry performance tests of the INER's RPLGDs and the TLDs. The results mean that both kinds of dosemeters can meet the performance test criteria. An accreditation procedure for the institutes which provide the environmental dosimetry services in Taiwan was suggested based on the comparison results of these two dosimetry systems

  11. Thermoluminescent response of dosemeters TLD-100 exposed to distinct baker protocols, irradiation and reading

    International Nuclear Information System (INIS)

    Estrada E, D.

    2002-01-01

    The interest that motivated the realization of this work is the opposing discrepancy among the values of the efficiency thermoluminescent of heavy charged particles (PCP) regarding gamma radiation (η PCP , γ) reported in different works and gathered recently for Horowitz (Ho 01). The measures of relative thermoluminescent efficiency have importance in relation to the dosimetry associated to medical therapy with heavy charged particle. The measurement of η PCP , γ depends of multiple experimental factors. To understand this dependence it was quantified the effect of using different procedures experimental in the estimate of the relative thermoluminescent efficiency of dosemeters TLD-100 (LiF: Ti; Mg) for protons of 3 MeV regarding gamma rays of 60 Co (η PCP , γ), varying the lot, the presentation, the one baked and the team reader. When was used the same global procedure values they were obtained for (η PCP , γ) inside the interval [0.30, 0.58] for the peak 5 and [0.35, 0.76] for the total thermoluminescent signal (Tl). At the use different equipment, baked and lot are obtained maximum differences of 30%, 12% and 6% respectively in the values of (η PCP , γ) for the peak 5, and 25%, 28% and 7% for the total Tl signal. The changes more significant of 36% and 44% for peak 5 and total signal respectively are obtained when changing the presentation of the dosemeter. As a complementary investigation it was studied the distribution of the Tl signal of each peak in the deconvolution of the curve of brightness with regard to the total signal in exposed dosemeters to high fluence of protons (1x10 10 p/cm 2 ) varying the experimental protocol. It was found that the distribution of the Tl signal has a difference of the order of 5% when changing the used reading team. It was observed that the contribution of the peak 5 regarding the total signal are preserved when changing baked and that it results to be 8% greater for the presentation in dosemeters of 1 x 1 x 1 mm 3

  12. Thermoluminescence of novel zinc oxide nano phosphors obtained by glycine-based solution combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R., E-mail: victor.orante@polimeros.uson.mx [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico)

    2015-10-15

    Full text: High-dose thermoluminescence dosimetry properties of novel zinc oxide nano phosphors synthesized by a solution combustion method in a glycine-nitrate process are presented for the very first time in this work. Sintered particles with sizes ranging between ∼500 nm and ∼2 μm were obtained by annealing the synthesized Zn O at 900 degrees C during 2 h in air. X-ray diffraction patterns indicate the presence of the Zn O hexagonal phase, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima: one located at ∼ 149 degrees C and another at ∼ 308 degrees C, the latter being the dosimetric component of the curve. The integrated Tl fading displays an asymptotic behaviour for times longer than 16 h between irradiation and the corresponding Tl readout, as well as a linear behaviour of the dose response without saturation in the studied dose interval (from 12.5 up to 400 Gy). Such features place synthesized Zn O as a promising material for high-dose radiation dosimetry applications. (Author)

  13. Thermoluminescence of novel zinc oxide nano phosphors obtained by glycine-based solution combustion synthesis

    International Nuclear Information System (INIS)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C.; Bernal, R.

    2015-10-01

    Full text: High-dose thermoluminescence dosimetry properties of novel zinc oxide nano phosphors synthesized by a solution combustion method in a glycine-nitrate process are presented for the very first time in this work. Sintered particles with sizes ranging between ∼500 nm and ∼2 μm were obtained by annealing the synthesized Zn O at 900 degrees C during 2 h in air. X-ray diffraction patterns indicate the presence of the Zn O hexagonal phase, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima: one located at ∼ 149 degrees C and another at ∼ 308 degrees C, the latter being the dosimetric component of the curve. The integrated Tl fading displays an asymptotic behaviour for times longer than 16 h between irradiation and the corresponding Tl readout, as well as a linear behaviour of the dose response without saturation in the studied dose interval (from 12.5 up to 400 Gy). Such features place synthesized Zn O as a promising material for high-dose radiation dosimetry applications. (Author)

  14. Thermoluminescence of Zn O thin films deposited by chemical bath; Termoluminiscencia de peliculas delgadas de ZnO depositadas por bano quimico

    Energy Technology Data Exchange (ETDEWEB)

    Camacho A, M. C.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal H, R.; Berman M, D. [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico); Castano M, V. M., E-mail: carmencamacho@gimmunison.com [UNAM, Instituto de Fisica, Centro de Fisica Aplicada y Tecnologia Avanzada, Apdo. Postal 1-1010, 76000 Queretaro, Qro. (Mexico)

    2015-10-15

    Full text: Zn O films on Si were synthesized using a deposition method by chemical bath and thermally treated at 900 degrees C for 12 h in air. The morphological characterization by scanning electron microscopy reveals that uniform films were obtained. To investigate the thermoluminescent properties of the films were exposed to irradiation with beta particles with doses in the range from 0.5 to 128 Gy. The brightness curves obtained using a heating rate of 5 degrees C have two peaks, one at 124 and another at 270 degrees C, and a linear dependence of the integrated thermoluminescence as a function of dose. The second maximum reveals the existence of localized trapping states of potential utility in thermoluminescent dosimetry. (Author)

  15. Radiation dosimetry

    International Nuclear Information System (INIS)

    Harper, M.W.; Thomas, B.; Conway, J.

    1977-01-01

    A dosemeter is described that is based on the TSCD principle (thermally stimulated current dosimetry). Basically this involves irradiating a responsive material and then heating it,whereby an electric current is produced. If the material is heated in an electric field the peak value of the thermally stimulated current or alternatively the total charge released by heating, can be related to the radiation dose received. The instrument described utilises a sheet coated with a thermoplastic polymer, such as a poly4-methylpent-l-ene. The polymer should have a softening point not lower than 150 0 C with an electrical resistivity of at least 10 16 chms/cm at 150 0 C. The polymer may also be PTFE. Heating should be in the range 150 0 C to 200 0 C and the electric field in the range 50 to 10,000V/mm. (U.K.)

  16. Recent advances in thermoluminescence dating

    International Nuclear Information System (INIS)

    Aitken, M.J.

    1984-01-01

    Initially the application of thermoluminescent dating was to ancient pottery and other baked clay, the detection of forgeries in art ceramics having a particularly powerful impact. In recent years there has been a growing extension of TL into non-pottery materials. Heated flints from paleolithic fire-places is one application. Another is in the dating of igneous rocks from recent volcanic events; formerly this had been impossible on account of the malign phenomenon of non-thermal ('anomalous') fading exhibited by volcanic minerals but this is now being circumvented by utilising TL in the 600 0 C region of the glow curve. TL dating has also been extended to unburnt calcite, one application being stalagmitic floors in paleolithic caves. Another recent development is the use of TL for dating aeolian sediment and some types of waterborne sediment. These developments give prospect of establishing a TL-based chronology, both for archaeology and quaternary research, extending back well beyond the range of radiocarbon, perhaps reaching a million years ago. (author)

  17. Organ dosimetry

    International Nuclear Information System (INIS)

    Kaul, Dean C.; Egbert, Stephen D.; Otis, Mark D.; Kuhn, Thomas; Kerr, George D.; Eckerman, Keith F.; Cristy, Mark; Ryman, Jeffrey C.; Tang, Jabo S.; Maruyama, Takashi

    1987-01-01

    This chapter describes the technical approach, complicating factors, and sensitivities and uncertainties of calculations of doses to the organs of the A-bomb survivors. It is the object of the effort so described to provide data that enables the dosimetry system to determine the fluence, kerma, absorbed dose, and similar quantities in 14 organs and the fetus, specified as being of radiobiological interest. This object was accomplished through the use of adjoint Monte Carlo computations, which use a number of random particle histories to determine the relationship of incident neutrons and gamma rays to those transported to a target organ. The system uses these histories to correlate externally-incident energy- and angle-differential fluences with the fluence spectrum (energy differential only) within the target organ. In order for the system to work in the most efficient manner possible, two levels of data were provided. The first level, represented by approximately 6,000 random adjoint-particle histories, enables the computation of the fluence spectrum with sufficient precision to provide statistically reliable (± 6 %) mean doses within any given organ. With this limited history inventory, the system can be run rapidly for all survivors. Mean organ dose and dose uncertainty are obtainable in this mode. The second mode of operation enables the system to produce a good approximation to fluence spectrum within any organ or to produce the dose in each of an array of organ subvolumes. To be statistically reliable, this level of detail requires far more random histories, approximately 40,000 per organ. Thus, operation of the dosimetry system in this mode (i.e., with this data set) is intended to be on an as-needed, organ-specific basis, since the system run time is eight times that in the mean dose mode. (author)

  18. Thermoluminescent dosimeters (TLD) quality assurance network in the Czech Republic.

    Science.gov (United States)

    Kroutilķková, Daniela; Novotný, Josef; Judas, Libor

    2003-02-01

    The Czech thermoluminescent dosimeters (TLD) quality assurance network was established in 1997. Its aim is to pursue a regular independent quality audit in Czech radiotherapy centres and to support state supervision. The audit is realised via mailed TL dosimetry. The TLD system consists of encapsulated LiF:Mg,Ti powder (type MT-N) read with Harshaw manual reader model 4000. Basic mode of the TLD audit covers measurements under reference conditions, specifically beam calibration checks for all clinically used photon and electron beams. Advanced mode consists of measurements under both reference and non-reference conditions using a solid multipurpose phantom ('Leuven phantom') for photon beams. The radiotherapy centres are instructed to deliver to the TLD on central beam axis absorbed dose of 2 Gy calculated with their treatment planning system for a particular treatment set-up. The TLD measured doses are compared with the calculated ones. Deviations of +/-3% are considered acceptable for both basic and advanced mode of the audit. There are 34 radiotherapy centres in the Czech Republic. They undergo the basic mode of the TLD audit regularly every 2 years. If a centre shows a deviation outside the acceptance level, it is audited more often. Presently, most of the checked beams comply with the acceptance level. The advanced TLD audit has been implemented as a pilot study for the present. The results were mostly within the acceptance limit for the measurements on-axis, whereas for off-axis points they fell beyond the limit more frequently, especially for set-ups with inhomogeneities, oblique incidence and wedges. The results prove the importance of the national TLD quality assurance network. It has contributed to the improvement of clinical dosimetry in the Czech Republic. In addition, it helps the regulatory authority to monitor effectively and regularly radiotherapy centres.

  19. Thermoluminescent dosimeters (TLD) quality assurance network in the Czech Republic

    International Nuclear Information System (INIS)

    Kroutilikova, Daniela; Novotny, Josef; Judas, Libor

    2003-01-01

    Introduction: The Czech thermoluminescent dosimeters (TLD) quality assurance network was established in 1997. Its aim is to pursue a regular independent quality audit in Czech radiotherapy centres and to support state supervision. Materials and methods: The audit is realised via mailed TL dosimetry. The TLD system consists of encapsulated LiF:Mg,Ti powder (type MT-N) read with Harshaw manual reader model 4000. Basic mode of the TLD audit covers measurements under reference conditions, specifically beam calibration checks for all clinically used photon and electron beams. Advanced mode consists of measurements under both reference and non-reference conditions using a solid multipurpose phantom ('Leuven phantom') for photon beams. The radiotherapy centres are instructed to deliver to the TLD on central beam axis absorbed dose of 2 Gy calculated with their treatment planning system for a particular treatment set-up. The TLD measured doses are compared with the calculated ones. Deviations of ±3% are considered acceptable for both basic and advanced mode of the audit. Results: There are 34 radiotherapy centres in the Czech Republic. They undergo the basic mode of the TLD audit regularly every 2 years. If a centre shows a deviation outside the acceptance level, it is audited more often. Presently, most of the checked beams comply with the acceptance level. The advanced TLD audit has been implemented as a pilot study for the present. The results were mostly within the acceptance limit for the measurements on-axis, whereas for off-axis points they fell beyond the limit more frequently, especially for set-ups with inhomogeneities, oblique incidence and wedges. Conclusions: The results prove the importance of the national TLD quality assurance network. It has contributed to the improvement of clinical dosimetry in the Czech Republic. In addition, it helps the regulatory authority to monitor effectively and regularly radiotherapy centres

  20. The thermoluminescence and optically stimulated luminescence properties of Cr-doped alpha alumina transparent ceramics

    International Nuclear Information System (INIS)

    Liu, Qiang; Yang, Qiu Hong; Zhao, Guang Gen; Lu, Shen Zhou; Zhang, Hao Jia

    2013-01-01

    Highlights: •Polycrystalline Cr:α-Al 2 O 3 transparent ceramics were obtained with vacuum sintering method. •The influence of different concentration of Cr 2 O 3 on the thermoluminescence and optical stimulated luminescence properties of Cr:α-Al 2 O 3 transparent ceramics was studied. •It had a main peak at 503 K of very high intensity and linear concentration dependence up to high concentration. •It showed so interesting results with high TL sensitivity and high stability of OSL signal that Cr:α-Al 2 O 3 transparent ceramics might be a promising material in TL dosimetry and replace Cr:α-Al 2 O 3 crystals. -- Abstract: Polycrystalline Cr:α-Al 2 O 3 transparent ceramics were fabricated by conventional solid-state processing under vacuum condition. The SEM microstructure photographs of Cr:α-Al 2 O 3 transparent ceramics doped with different content of Cr 2 O 3 were investigated. The absorption, emission spectra, thermoluminescence and optical stimulated luminescence of Cr:α-Al 2 O 3 transparent ceramics were comparable to those of Cr:α-Al 2 O 3 crystals. The influence of different concentration of Cr 2 O 3 on the thermoluminescence and optical stimulated luminescence properties of Cr:α-Al 2 O 3 transparent ceramics was discussed. It showed so interesting results with high TL sensitivity and high stability of OSL signal that Cr:α-Al 2 O 3 transparent ceramics might be a promising material in TL dosimetry and replace Cr:α-Al 2 O 3 crystals

  1. Calibration of Mg2SiO4(Tb) thermoluminescent dosimeters for use in determining diagnostic X-ray doses to Adult Health Study participants

    International Nuclear Information System (INIS)

    Kato, Kazuo; Antoku, Shigetoshi; Sawada, Shozo; Russell, W.J.

    1989-11-01

    Characteristics of Mg 2 SiO 4 (Tb) thermoluminescent dosimeters (TLD) were ascertained preparatory to measuring dose from diagnostic X-ray examinations received by Adult Health Study participants. These detectors are small, relatively sensitive to low-dose X rays, and are appropriate for precise dosimetry. Extensive calibration is necessary for precisely determining doses according to their thermoluminescent intensities. Their sensitivities were investigated, by dose according to X-ray tube voltage, and by exposure direction, to obtain directional dependence. Dosimeter sensitivity lessened due to the fading effect and diminution of the planchet. However, these adverse effects can be avoided by storing the dosimeters at least 1.5 hours and by using fresh silver-plated planchets. Thus, the TLDs, for which sensitivities were determined in this study, will be useful in subsequent diagnostic X-ray dosimetry. (author)

  2. Issues in the reconstruction of environmental doses on the basis of thermoluminescence measurements in the Techa riverside

    Science.gov (United States)

    Bougrov, N. G.; Goksu, H. Y.; Haskell, E.; Degteva, M. O.; Meckbach, R.; Jacob, P.; Neta, P. I. (Principal Investigator)

    1998-01-01

    The potential of thermoluminescence measurements of bricks from the contaminated area of the Techa river valley, Southern Urals, Russia, for reconstructing external exposures of affected population groups has been studied. Thermoluminescence dating of background samples was used to evaluate the age of old buildings available on the river banks. The anthropogenic gamma dose accrued in exposed samples is determined by subtracting the natural radiation background dose for the corresponding age from the accumulated dose measured by thermoluminescence. For a site in the upper Techa river region, where the levels of external exposures were extremely high, the depth-dose distribution in bricks and the dependence of accidental dose on the height of the sampling position were determined. For the same site, Monte Carlo simulations of radiation transport were performed for different source configurations corresponding to the situation before and after the construction of a reservoir on the river and evacuation of the population in 1956. A comparison of the results provides an understanding of the features of the measured depth-dose distributions and height dependencies in terms of the source configurations and shows that bricks from the higher sampling positions are likely to have accrued a larger fraction of anthropogenic dose from the time before the construction of the reservoir. The applicability of the thermoluminescent dosimetry method to environmental dose reconstruction in the middle Techa region, where the external exposure was relatively low, was also investigated.

  3. New thermoluminescence techniques for mineral exploration

    International Nuclear Information System (INIS)

    Levy, P.W.; Holmes, R.J.; Ypma, P.J.; Chen, C.C.; Swiderski, H.S.

    1977-01-01

    The thermoluminescence of carbonate host rock in the vicinity of known lead-zinc and lead-zinc-fluorite mineralization was reexamined for possible development as an exploration technique. The measurements were made with equipment for determining the thermoluminescence spectrum at closely spaced temperature intervals. Radiation-induced thermoluminescence was also measured. Samples were studied from five localities in Mexico, Southwest Africa, and the United States. Four thermoluminescence properties were found to vary with ''distance-from-ore'' in a systematic manner. These include the glow peak intensity and temperature and the emission spectrum peak energy and full width at half-maximum. For example, in both limestone and dolomite, the high-temperature glow peak intensities are low or negligible within the ore and as the distance from the contact increases the intensity rises rapidly to a maximum, or maxima, and then decreases irregularly to constant value slightly above that in the ore. Depending on the thickness of the ore, the thermoluminescence characteristics associated with the mineralization extended from ten to a hundred or so meters from the ore host rock contact. 5 figures

  4. Characteristic of 120 degree C thermoluminescence peak of iceland spar

    International Nuclear Information System (INIS)

    Lu Xinwei; Han Jia

    2006-01-01

    The basic characteristic of 120 degree C thermoluminescence peak of iceland spar was studied. The experimental result indicates the longevity of 120 degree C thermoluminescence peak of iceland spar is about 2 h under 30 degree C. The thermoluminescence peak moves to the high temperature when the heating speed increasing. The intensity of 120 degree C thermoluminescence peak of iceland spar is directly proportional to radiation dose under 15 Gy. (authors)

  5. Comparative analysis of dose rates in bricks determined by neutron activation analysis, alpha counting and X-ray fluorescence analysis for the thermoluminescence fine grain dating method

    Czech Academy of Sciences Publication Activity Database

    Bártová, H.; Kučera, Jan; Musílek, L.; Trojek, T.

    2014-01-01

    Roč. 104, NOV (2014), s. 393-397 ISSN 0969-806X. [1st International Conference on Dosimetry and its Applications (ICDA). Prague, 23.6.2013-28.6.2013] R&D Projects: GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : Alpha coutning * neutron activation analysis * X-ray fluorescence * thermoluminescence dating * dose rate Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.380, year: 2014

  6. Dosimetry comparison of pelvimetry methods using conventional radiographs and CT

    International Nuclear Information System (INIS)

    Resten, A.; Suissa, M.; Musset, D.; Mausoleo, F.; Valero, M.; Taylor, S.

    2001-01-01

    To determine the fetal and maternal exposure to radiation by use of thermoluminescent dosimeters in order to compare conventional and CT-scan X-ray. Dosimetry was performed with an anthropomorph phantom. Thermoluminescent dosimeters were positioned on the surface and in the depth of the phantom. Digital radiography of the pelvis was performed according to a standard technique. CT-scan of the pelvis was performed according to the Buthiau's technique. With CT, the dose reached 0.31 to 4.95 mGy, with a dose of 2.32 mGy for the fetal gonads. With standard technique, the doses reached 0.03 to 0.39 mGy, with a dose of 0.39 mGy for the fetal gonads. With CT the fetus and the mother were exposed to 1/10. of the total dose delivered using conventional X-rays and the dose distribution was more homogeneous. (author)

  7. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    shapes and sizes while sparing normal tissue. The situation is further complicated if the normal tissues are critical organs or are particularly sensitive to radiation. Radiotherapy techniques employed to obtain a closer conformation of the dose distribution to the tumour volume are referred to as conformal radiotherapy techniques. The clinical implementation of conformal therapy has been delayed by limitations in the verification of conformal dose distributions calculated by treatment planning systems prior to the irradiation of the patient and the verification of complex treatments during its delivery to the patient. There are several aspects of conformal therapy that complicate dose verification. To achieve the dose distributions conforming to complex 3D volumes, high dose gradients arise in the treatment volume. Further, overdose or underdose regions can exist when separate radiation fields are used to deliver additional radiation. These aspects require that practical dose measurement (dosimetry) techniques be able to integrate dose over time and easily measure dose distributions in 3D with high spatial resolution. Traditional dosimeters, such as ion chambers, thermoluminescent dosimeters and radiographic film do not fulfil these requirements. Novel gel dosimetry techniques are being developed in which dose distributions can potentially be determined in vitro in 3D using anthropomorphic phantoms to simulate a clinically irradiated situation. As long ago as the 1950's, radiation-induced colour change in dyes was used to investigate radiation doses in gels. It was subsequently shown that radiation induced changes in nuclear magnetic resonance (NMR) relaxation properties of gels infused with conventional Fricke dosimetry solutions could be measured using magnetic resonance imaging (MRI). In Fricke gels, Fe 2+ ions in ferrous sulphate solutions are usually dispersed throughout a gelatin, agarose or PVA matrix. Radiation-induced changes in the dosimeters are considered to

  8. Application of TL dosimetry in epidemiological studies in HBRAs

    International Nuclear Information System (INIS)

    Chougaonkar, M.P.

    2006-01-01

    Luminescence as a phenomenon has been extensively used in radiation dosimetry, using thermoluminescence. The nuclear industry all over the world over uses TL dosimetry in radiation protection since they have to ensure that the radiation workers and workers involved in industrial applications of radiation sources are not exposed beyond limits set by international monitoring bodies. They have also to ensure that the nuclear applications do not give rise to elevated radiation levels in the environs. In addition, epidemiologists and radiobiologists world over have been working over the past few decades, to study health effects of chronic radiation exposures in populations living in the elevated natural radiation environment. This paper discusses the importance of dosimetric studies, in the normal as well as high background radiation areas (HBRAs), due to the radiation effects on the humans. The application of thermoluminescent dosimeters (TLDs) in population dosimetry with the end point of epidemiological studies is then discussed. The paper outlines the construction of TLDs, methodology of deployment and retrieval and analysis to arrive the dose. To obtain total dose, dosimetric techniques suitable for external gamma radiation, inhalation dose due to radon, thoron and their progenies and radiological analysis of the food items is required. The techniques arriving at the effective dose are outlined. Basics of epidemiological analysis, particularly using case-control methodology and its advantages/ disadvantages are also discussed. Using the previous work by the author, the paper also reviews various analyses that can be carried out the dosimetric data. (author)

  9. Synthetic diamond devices for medical dosimetry applied to radiotherapy

    International Nuclear Information System (INIS)

    Descamps, C.

    2007-06-01

    The aim of this thesis, lead in the framework of an integrated European project entitled M.A.E.S.T.R.O. for ' Methods and Advanced Equipment for Simulation and Treatment in Radio Oncology', was to develop and test synthetic diamond detector in clinical environment for new modalities used in radiotherapy. Diamond is a good candidate for the detection of high energy beams in medical fields. It can be used for passive dosimetry, as thermoluminescent dosimeters or for active dosimetry as ionisation chambers. These two applications are presented here. Concerning the thermoluminescence, several impurities or dopants (boron, phosphorus, and nitrogen) have been incorporated in the diamond films during growth, in order to modify the material dosimetric properties and a detailed study of nitrogen-containing films is proposed. The second part presents the results obtained in active dosimetry. Two guide lines were followed: the measurement set-up optimisation and the material modification. The first dosimetric studies under radiotherapy beams concerning nitrogen-containing polycrystalline diamond as well as high purity single crystal diamond are conclusive. The detectors behaviours are in agreement with the recommendations of the International Atomic Energy Agency (IAEA). (author)

  10. CVD diamonds as thermoluminescent detectors for medical applications

    International Nuclear Information System (INIS)

    Marczewska, B.; Olko, P.; Nesladek, M.; Waligorski, M.P.R.; Kerremans, Y.

    2002-01-01

    Diamond is believed to be a promising material for medical dosimetry due to its tissue equivalence, mechanical and radiation hardness, and lack of solubility in water or in disinfecting agents. A number of diamond samples, obtained under different growth conditions at Limburg University, using the chemical vapour deposition (CVD) technique, was tested as thermoluminescence dosemeters. Their TL glow curve, TL response after doses of gamma rays, fading, and so on were studied at dose levels and for radiation modalities typical for radiotherapy. The investigated CVD diamonds displayed sensitivity comparable with that of MTS-N (Li:Mg,Ti) detectors, signal stability (reproducibility after several readouts) below 10% (1 SD) and no fading was found four days after irradiation. A dedicated CVD diamond plate was grown, cut into 20 detector chips (3x3x0.5 mm) and used for measuring the dose-depth distribution at different depths in a water phantom, for 60 Co and six MV X ray radiotherapy beams. Due to the sensitivity of diamond to ambient light, it was difficult to achieve reproducibility comparable with that of standard LiF detectors. (author)

  11. Effect of the radiation in the thermoluminescent properties of lava

    CERN Document Server

    Correcher, V; García, J

    2003-01-01

    Blue thermoluminescence (Tl) emission from different lavas of many places (Costa Rica, Canary Islands, Hawaii Islands, Iceland and Italy) corresponding to different eruptions has been studied to know its potential use in the field of dating and retrospective dosimetry. Due to the light emission is linked to the point defects of the crystalline lattice structure, X-ray diffraction analyses were performed to determine the components of this poly mineral material that mostly are cristobalite, plagioclase and phyllosilicates. Exposures to different doses (in a range of 1-25 Gy) were given to each sample to determine the evolution of the Tl signal with the irradiation under laboratory conditions. In all cases, a linear response could be observed and no saturation has been detected in this range of doses. Both natural (NTL) and induced (ITL) Tl signal exhibit a complex glow curve structure associated to a continuous trap distribution over 100 C that could be attributed to the formation-annihilation [Al0 sub 4 /alka...

  12. Thermoluminescent study of the hydroxyapatite irradiated with gamma radiation

    International Nuclear Information System (INIS)

    Mendoza A, D.; Hernandez A, M.; Gonzalez, P.R.; Rodriguez L, V.

    2002-01-01

    Recently in dosimetry, it has been common to use bones and teeth for detecting and measuring radiation. However it has been observed that the efficiency of detection depends on the consistency of these tissues. Since the hydroxyapatite [Ca 10 (PO 4 ) 6 (OH) 2 ] is the main mineral component of the bones and teeth, it has been suggested as material for detecting and measuring of radiations, quantifying the free radicals produced by radiation. In this work a study about the thermoluminescent properties (Tl) induced by radiation in the synthetic hydroxyapatite obtained by hydrothermal method is presented. The results have shown that this mineral presents a Tl signal whose curve contains two maximums located around 150 and 250 C degrees, respectively. Likewise, a linear behavior of the Tl signal of function of dose in the interval 10-100 Gy was observed. These results are important since that they open the possibility to use biomaterials in the dosimetric area, when they only were used for grafting in the biomedical area. (Author)

  13. Radioluminescence and thermoluminescence of albite at low temperature

    International Nuclear Information System (INIS)

    Can, N.; Garcia-Guinea, J.; Kibar, R.; Cetin, A.; Ayvacikli, M.; Townsend, P.D.

    2011-01-01

    Feldspar as an archaeological and geological natural material for dating and retrospective dosimetry is receiving more and more attention because of its useful luminescence properties. In this study, the 25-280 K thermoluminescence (TL) and radioluminescence (RL) spectra in albite, which is a component of the two main feldspar series, the alkali feldspar (Na, K)AlSi 3 O 8 and the plagioclases (NaAlSi 3 O 8 -CaAl 2 Si 2 O 8 ) have been presented for aliquots along (001) and (010) crystallographic orientations. There are four main emission bands that are considered to arise from complexes of intrinsic defects linked in larger complexes with impurities such as Na + , Mn 2+ or Fe 3+ ions. The consequence of their association is to produce different luminescence efficiencies that produce wavelength sensitive TL curves. Radioluminescence data at low temperature for albites is distorted by contributions from the TL sites, even when the RL is run in a cooling cycle. This indicates the potential for a far more general problem for analysis of low temperature RL in insulating materials. - Highlights: → TL and RL spectra in albite were presented for different orientations. → There are 4 emission bands that are considered to arise from complexes of intrinsic. → RL data at low temperature for albite is distorted by contributions from TL sites. → This indicates the potential problem for analysis of low temperature RL.

  14. Work place monitoring in accelerator facilities using thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Ribeiro, M.S.; Sanches, M.P.; Osima, A.M.; Rodriguez, D.L.; Carvalho, R.N.; Somessari, R.N.

    1998-01-01

    The increase in the use of large amounts of energy and large particles accelerators in development or in industrial processes for the reticulation, polymerization and sterilization of cables and wires allowed to discover and monitor work places in facilities having particle accelerators at the Institute of Energy and Nuclear Inquiries Comissao National de Energy Nuclear. Measures previously taken by technicians in routine monitoring, show that radiation doses found in the beams tube and at the door of the accelerator area is high enough to require routine programs to monitor work places at the installation. That is why, fifteen thermoluminescent dosimeters (TLD) where placed in different points of the facility where doses must be measured along a three month period and at the same time readings must be taken from control dosimeters kept within a shielded container. The monitor had a small double layer with three pellets of TLD CaSO4 Dy inside of a route carrier adopted in routine workers dosimetry usually. Outcomes show that the radiological protection program must be implemented to ameliorate and guarantee safety procedures

  15. Study of the thermoluminescent properties of lava from different origins

    International Nuclear Information System (INIS)

    Molina, D.; Correcher, V.; Delgado, A.; Garcia G, J.

    2002-01-01

    In this work has been studied the thermoluminescent signal (Tl) of lava from different geographical area (Costa Rica, the Canary Islands, Hawaii, Iceland and Italy) and originating in distinct eruptions, for its possible use such as in the dating field (geological and archaeological) as in retrospective dosimetry. Due that the light emission is intimately related with the punctual defects existent in the structure of material associated to the presence of different mineral phases, it was realized a study by X-ray diffraction for determining the main components of the lava observing the presence, in distinct proportions of cristobalite, plagioclases (chalcosodic feldspars) and philosilicates (augite, montmorillonite, forsterite and actinolite). All the detected mineral components present Tl emission in the blue region. Each one of the lava were artificially irradiated for proving the dependence of the luminescent signal with the dose in the range 1 to 25 Gy, observing a linear response with the dose in all the cases and not appreciating saturation in the Tl emission. Such the appropriate signal of natural samples (TLN) as the irradiated samples in the laboratory (TLI) show a complex structure associated with a continuous distribution of traps at temperature higher than 100 C which could be explained as consequence of the dynamic formation-annihilation of centers [AlO 4 /alkali] + and [AlO 4 ] 0 . In TLI was observed that a nearer to 85 C appeared a maximum whose structure correspond a discrete distribution of traps, coexisting therefore the two types of traps structure. (Author)

  16. Thermoluminescence properties of alkali borate glasses containing neodymium

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, A.F.; Henaish, B.A.; Kenaway, M.A.; Salem, L.R.

    1988-01-01

    The thermoluminescence properties of sodium borate glasses as a function of neodymium oxide content as well as the divalent metal oxides (RO = ZnO, MgO and CaO) in replacement of Na/sub 2/O have been investigated. It is observed that the addition of Nd/sub 2/O/sub 3/ imparts to the host glass a monopeak glow curve according to an active luminescent centre (E approx. = 0.97 eV to 1.232 eV). The gradual addition of neodymium oxide to the sodium borate glass causes gradual enhancement in the TL-intensity up to a quenching concentration value (4 g Nd/sub 2/O/sub 3/ added to 100 g of borate glass) above which a draw back in TL-intensity occurs. On the other hand the replacement of 5 wt% Na/sub 2/O by RO shows that CaO dominates the other two divalent metal oxides used, as it possesses a much deeper luminescent trap (1.232 eV). The results obtained suggest that these glasses can be used in radiation detection and dosimetry. The ..gamma..-induced Tl-signal of such type of glass is found to be reproducible within an acceptable error of not more than 3.5% in all individual and group scattering over the detector samples each of which is used 10 times for evaluating the same ..gamma..-dose.

  17. Personnel neutron dosimetry

    International Nuclear Information System (INIS)

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs

  18. Development of thermoluminescence dating techniques at Oxford

    International Nuclear Information System (INIS)

    Fleming, S.J.

    1977-01-01

    The two-decade long history of thermoluminescene as a pottery dating method is surveyed with particular reference to the various problems that have been encountered in the Oxford Laboratory's research programme. Effects, such as supralinearity and radon emanation, are explained in terms of how they are measured and how their existence influences thermoluminescence (TL) dating accuracy (currently close to plus minus 7% per analysis). Illustrations of Thermoluminescence (TL) applications include a Nok culture terracotta from Nigeria and a Cambodia bronze Buddha figure of the Khmer period, dated ising the ceramic-like casting-core retained within it. (author)

  19. Thermoluminescence: Potential Applications in Forensic Science

    Science.gov (United States)

    Ingham, J. D.; Lawson, D. D.

    1973-01-01

    In crime laboratories one of the most difficult operations is to determine unequivocally whether or not two samples of evidence of the same type were originally part of the same thing or were from the same source. It has been found that high temperature thermoluminescence (room temperature to 723 K) can be used for comparisons of this type, although work to date indicates that there is generally a finite probability for coincidental matching of glass or soil samples. Further work is required to determine and attempt to minimize these probabilities for different types of materials, and to define more clearly the scope of applicability of thermoluminescence to actual forensic situations.

  20. Annual radiation dose in thermoluminescence dating

    International Nuclear Information System (INIS)

    Li Huhou

    1988-01-01

    The annual radiation dose in thermoluminescence dating has been discussed. The autor gives an entirely new concept of the enviromental radiation in the thermoluminescence dating. Methods of annual dose detemination used by author are dating. Methods of annual dose determination used by author are summed up, and the results of different methods are compared. The emanium escapiug of three radioactive decay serieses in nature has been considered, and several determination methods are described. The contribution of cosmic rays for the annual radiation dose has been mentioned

  1. Annual radiation dose in thermoluminescence dating

    Energy Technology Data Exchange (ETDEWEB)

    Huhou, Li [Chinese Academy of Social Sciences, Beijing, BJ (China). Inst. of Archaeology

    1988-11-01

    The annual radiation dose in thermoluminescence dating has been discussed. The autor gives an entirely new concept of the enviromental radiation in the thermoluminescence dating. Methods of annual dose detemination used by author are dating. Methods of annual dose determination used by author are summed up, and the results of different methods are compared. The emanium escapiug of three radioactive decay serieses in nature has been considered, and several determination methods are described. The contribution of cosmic rays for the annual radiation dose has been mentioned.

  2. Synthetic diamond devices for radiotherapy applications: Thermoluminescent dosimeter and ionisation chamber

    International Nuclear Information System (INIS)

    Descamps, C.; Tromson, D.; Mer, C.; Nesladek, M.; Bergonzo, P.

    2006-01-01

    In radiotherapy field, the major usage of dosimeters is in the measurement of the dose received by the patient during radiotherapy (in-vivo measurements) and in beam calibration and uniformity checks. Diamond exhibits several interesting characteristics that make it a good candidate for radiation detection. It is indeed soft-tissue equivalent (Z=6 compared to Z=7.42 for human tissue), mechanically robust and relatively insensitive to radiation damage, chemically stable and non toxic. Moreover, the recent availability of synthetic samples, grown under controlled conditions using the chemical vapour deposition (C.V.D.) technique, allowed decreasing the high cost and the long delivery time of diamond devices. Diamond can be use for off-line dosimetry as thermoluminescent dosimeters or for on-line dosimetry as ionisation chamber [2,3]. These both applications are reported here. For this study, samples were grown in the laboratory and devices were then tested under X-ray irradiations and in clinical environment under medical cobalt source. The work described in this paper was performed in the framework of the European Integrated Project M.A.E.S.T.R.O., Methods and Advanced Equipment for Simulation and Treatment in Radio-Oncology, (6. FP) which is granted by the European Commission.The first results of this study clearly show that C.V.D. diamond detectors are suitable for dosimetry in radiotherapy applications. Moreover, for both T.L. dosimeters and ionisation chambers applications, and even though the sensitivity is subsequently reduced, nitrogen incorporation in films seems to significantly improve the dosimetric characteristics of the devices. Therefore, the optimisation of the material quality appears as a very important issue in order to increase the dosimetric characteristics of devices and more particularly, for use as thermoluminescent dosimeters, other impurities (Nickel, Phosphorus) will be tested. For ionisation chamber applications, experiments with

  3. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  4. Neutron dosimetry - A review

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J W

    1955-03-29

    This review summarizes information on the following subjects: (1) physical processes of importance in neutron dosimetry; (2) biological effects of neutrons; (3) neutron sources; and (4) instruments and methods used in neutron dosimetry. Also, possible improvements in dosimetry instrumentation are outlined and discussed. (author)

  5. Progress in high-dose radiation dosimetry

    International Nuclear Information System (INIS)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expanded applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Reference systems also include a number of chemical dose meters: ferrous sulphate, ferrous-cupric sulphate, and ceric sulphate acidic aqueous solutions. Requirements for stable and reliable transfer dose meters have led to further developments of several important high-dose systems: amino acids and saccharides analysed by ESR or lyoluminescence, thermoluminescent materials, radiochromic dyes and plastics, ceric-cerous solutions analysed by potentiometry, and ethanol-chlorobenzene solutions analysed by high-frequency oscillometry. A number of other prospective dose meters are also treated in this review. In addition, an IAEA programme of high-dose standardization and intercomparison for industrial radiation processing is described. (author)

  6. Dosimetry and bone densitometry. Comparison between lunar 1Q and Hologic 4500A

    International Nuclear Information System (INIS)

    Philippon, B.; Duboeuf, F.; Itti, R.

    2002-01-01

    Patient dosimetry related to two bone densitometer units from different manufacturers (LUNAR IQ and HOLOGIC 4500A) were evaluated using the parallel beam technique and thermoluminescence from Ca (SO4)/Dy. The radiation dose measured for a phantom of 18 cm in thickness was 0,11 mGy (+/- 0,004) at a maximum current of 3 mA for the LUNAR IQ unit in the high-resolution mode. The radiation dose is 0,28 mGy (+/- 0,011) for the HOLOGIC 4500A unit used at 2,5 mA in the high resolution-mode. These results obtained by thermoluminescence of the Ca (SO4)/Dy are in favor of the LUNAR IQ unit. However, dosimetry must be weighted against image quality. (author)

  7. Chemical dosimetry principles in high dose dosimetry

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.

    2016-01-01

    In radiation processing, activities of principal concern are process validation and process control. The objective of such formalized procedures is to establish documentary evidence that the irradiation process has achieved the desired results. The key element of such activities is inevitably a well characterized reliable dosimetry system that is traceable to recognized national and international dosimetry standards. Only such dosimetry systems can help establish the required documentary evidence. In addition, industrial radiation processing such as irradiation of foodstuffs and sterilization of health careproducts are both highly regulated, in particular with regard to dose. Besides, dosimetry is necessary for scaling up processes from the research level to the industrial level. Thus, accurate dosimetry is indispensable

  8. Re-use of radio-thermoluminescent LiF without regeneration; Reemploi sans regeneration du LiF radiothermoluminescent

    Energy Technology Data Exchange (ETDEWEB)

    Portal, G; Francois, H; Blanchard, Ph [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    There is at the present time a rapid development of dosimetry techniques using thermoluminescence. Amongst the many substance actually in use, research laboratories generally employ lithium fluoride which is of particular interest for dosing {beta} radiation and low-energy X and {gamma} radiation. It might also be of use in radioprotection if its practical application were simpler. It has in effect unstable traps situated just below the surface which adversely affect the measurements if the material is not regenerated before each operation; this process considerably complicates the carrying out of measurements in the field of radioprotection. We have prepared a lithium fluoride giving unstable peaks which are less pronounced that those of the commercially available product and which can therefore be used without regeneration. In this report we compare the thermoluminescence curves for these two products. An analysis is given of the reasons for which this radio-thermoluminescent product has a stable luminescence curve and can be used almost one hundred times without being regenerated. We show that this quality can be retained when the LiF is used as a filler for teflon for applications in detectors. (authors) [French] On assiste a un developpement rapide des techniques de dosimetrie par thermoluminescence. Parmi les nombreux materiaux actuellement utilises, les laboratoires de recherche font generalement porter leur preference sur le fluorure de lithium qui est particulierement interessant pour la dosimetrie des rayonnements {beta} et des rayonnements X et {gamma} de faible energie. Ses qualites seraient egalement appreciees en radioprotection si sa mise en oeuvre etait plus simple. Il presente en effet des pieges instables situes a une faible profondeur qui alterent les mesures si l'on ne procede pas, avant chaque utilisation, a la regeneration du materiau, operation qui alourdit considerablement les mesures pratiquees en radioprotection. Nous avons prepare un

  9. International nuclear accident dosimetry intercomparison: results of Czech participation

    International Nuclear Information System (INIS)

    Spurny, F.; Votockova, I.

    1996-01-01

    An international intercomparison scheme for criticality accident dosimetry systems took place at the SILENE reactor, Valduc, France in June 1993. The dosemeters were exposed both on phantoms and in free air to radiation from the reactor, both shielded by lead and bare. The results obtained during this event by Czech participants are presented and compared with the average values obtained by the complete group of participants and with the reference values. The systems used consisted mostly of Si-diodes and thermoluminescent detectors, some supporting measurements were performed with solid state nuclear track detectors and using the albedo principle. The agreement between the data sets is very good. 7 tabs., 13 refs

  10. Biological dosimetry studies for boron neutron capture therapy at the RA-1 research reactor facility

    International Nuclear Information System (INIS)

    Trivillin, Veronica A.; Heber, Elisa M.; Itoiz, Maria E.; Schwint, Amanda E.; Castillo, Jorge

    2004-01-01

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminescent dosimeters to characterize the BNCT facility developed at the RA-1 research reactor operated by the National Atomic Energy Commission in Buenos Aires. Biological dosimetry was performed employing the hamster cheek pouch oral cancer model previously validated for BNCT studies by our group. Results indicate that the RA-1 neutron source produces useful dose rates for BNCT studies but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications. (author)

  11. Review of present beta dosimetry problems in radiation protection; to day's answers and future trends

    International Nuclear Information System (INIS)

    Fracas, P.

    1986-01-01

    The large use of pure beta radionuclides needs to be develop beta dosimetry methods for radiation protection. The different types of present dosimetry assessments are reviewed. In all the cases the quantity to take into account is the absorbed dose rate in human tissus and more particularly in skin. In the case of point sources of known nature and activity this quantity can be worked out. This calculation is achieved either by incident beta spectrum analysis or theoretical considerations based on Kernel point. The absorbed dose rate can also be measured by extrapolation ionization chamber which characteristics and working are detailed here. All present survey meter were not initially planned for such a beta dosimetry, as this performed with the extrapolation ionization chamber which is taken here as a reference. So responses of usual dosimeters compared to this reference need to be estimated. Responses of personal film badges used in CEA, portable ionization chambers as babyline, pocket dosimeters SEQ7 and the thermoluminescent dosimeters TLD700 are exposed here. Results show that all these survey meters are not completely suitable for routine beta dosimetry. Consequently other operational dosimetry techniques have to be pursued. In particular some thermoluminescence dosimeters for instance boron diffused in surface layer and multi-elements, and furthermore Thermally Stimulated Exoelectron Emission (TSEE) and surface barrier detectors are described [fr

  12. Dosimetry system 1986

    International Nuclear Information System (INIS)

    Woolson, William A.; Egbert, Stephen D.; Gritzner, Michael L.

    1987-01-01

    In May 1983, the authors proposed a dosimetry system for use by the Radiation Effects Research Foundation (RERF) that would incorporate the new findings and calculations of the joint United States - Japan working groups on the reassessment of A-bomb dosimetry. The proposed dosimetry system evolved from extensive discussions with RERF personnel, numerous meetings of the scientists from Japan and the United States involved in the dosimetry reassessment research, and requirements expressed by epidemiologists and radiobiologists on the various review panels. The dosimetry system proposed was based on considerations of the dosimetry requirements for the normal work of RERF and for future research in radiobiology, the computerized input data on A-bomb survivors available in the RERF data base, the level of detail, precision, and accuracy of various components of the dosimetric estimates, and the computer resources available at RERF in Hiroshima. These discussions and our own experience indicated that, in light of the expansion of computer and radiation technologies and the desire for more detail in the dosimetry, an entirely new approach to the dosimetry system was appropriate. This resulted in a complete replacement of the T65D system as distinguished from a simpler approach involving a renormalization of T65D parameters to reflect the new dosimetry. The proposed dosimetry system for RERF and the plan for implementation was accepted by the Department of Energy (DOE) Working Group on A-bomb Dosimetry chaired by Dr. R.F. Christy. The dosimetry system plan was also presented to the binational A-bomb dosimetry review groups for critical comment and was discussed at joint US-Japan workshop. A prototype dosimetry system incorporating preliminary dosimetry estimates and applicable to only a limited set of A-bomb survivors was installed on the RERF computer system in the fall of 1984. This system was successfully operated at RERF and provided an initial look at the impact of

  13. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  14. Photoluminescence, trap states and thermoluminescence decay ...

    Indian Academy of Sciences (India)

    Administrator

    Photoluminescence, trap states and thermoluminescence decay process study of Ca2MgSi2O7 : Eu. 2+. , Dy. 3+ phosphor. RAVI SHRIVASTAVA*, JAGJEET KAUR, VIKAS DUBEY and BEENA JAYKUMAR. Govt. VYT PG Autonomous College, Durg 491 001, (C.G.) India. MS received 9 July 2013; revised 5 December 2013.

  15. Thermoluminescence in some copper-doped compounds

    International Nuclear Information System (INIS)

    Patil, R.R.; Moharil, S.V.; Dhopte, S.M.; Muthal, P.L.; Kondawar, V.K.

    2003-01-01

    Thermoluminescence (TL) in various Cu + -doped materials is studied. A good correlation between the presence of copper in the Cu + form and TL sensitivity is observed. Correlation between TL emission spectra and photoluminescence suggests that Cu + acts as the emission center in the TL process. (copyright 2003 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Rare earth oxyhalogenide base thermoluminescent material

    International Nuclear Information System (INIS)

    Rabatin, J.G.

    1976-01-01

    A process is described that consists to expose a thermoluminescent material to ionizing radiations, the material being a rare earth oxyhalogenide with terbium additions, to heat this material up to the emission of visible radiations and to measure the emitted radiations which are proportional to the ionizing radiation dose [fr

  17. Thermoluminescence of meteorites and their orbits

    Science.gov (United States)

    Melcher, C. L.

    1981-01-01

    The thermoluminescence levels of 45 ordinary chondrites are measured in order to provide information on the orbital characteristics of the meteorites before impact. Glow curves of the photon emission response of powdered samples of the meteorites to temperatures up to 550 C in the natural state and following irradiation by a laboratory test dose of 110,000 rad were obtained as functions of terrestrial age and compared to those of samples of the Pribram, Lost City and Innisfree meteorites, for which accurate orbital data is available. The thermoluminescence levels in 40 out of 42 meteorites are found to be similar to those of the three control samples, indicating that the vast majority of ordinary chondrites that survive atmospheric entry have perihelia in the range 0.8-1 AU. Of the remaining two, Farmville is observed to exhibit an unusually large gradient in thermoluminescence levels with sample depth, which may be a result of a temperature gradient arising in a slowly rotating meteorite. Finally, the thermoluminescence measured in the Malakal meteorite is found to be two orders of magnitude lower than control samples, which is best explained by thermal draining by solar heating in an orbit with a perihelion distance of 0.5 to 0.6 AU.

  18. Quality control of thermoluminesce personal dose monitoring

    International Nuclear Information System (INIS)

    Shang Aiguo; He Wenchang; Zhao Fengtao

    2006-01-01

    In order to evaluate the influence factor to thermoluminesce personal dose monitoring result, the every question that can appear based on the fact was analyzed. The results show that the detector, annealing, measuring process can influence the monitoring result. It gives some measures to enhance monitoring quality. (authors)

  19. Obtention of thermoluminescent efficiencies by means of irradiation of TLD-100 dosemeters with proton beams helium and carbon

    International Nuclear Information System (INIS)

    Avila, O.; Rodriguez V, M.; Aviles, P.; Gamboa de Buen, I.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E.

    2002-01-01

    In this work, the advances of a serial of measurements of relative efficiency thermoluminescent of heavy charged particles (PCP) with respect to gamma radiation for TLD-100, dosemeters of LiF: Mg,Ti manufactured by the Harshaw-Bicron company are reported. The PCP are essentials in the implementation of dosimetry associated with medical applications. The measurements before gamma radiation were carrying out using the Vickrad irradiator of the National Institute of Nuclear Research at dose of 1.663 Gy. The measures which are reported about protons, helium and carbon were realized using the Pelletron accelerator of the Physics Institute of the UNAM. (Author)

  20. Lower limits of detection in using carbon nanotubes as thermoluminescent dosimeters of beta radiation

    Science.gov (United States)

    Alanazi, Abdulaziz; Jurewicz, Izabela; Alalawi, Amani I.; Alyahyawi, Amjad; Alsubaie, Abdullah; Hinder, Steven; Bañuls-Ciscar, Jorge; Alkhorayef, Mohammed; Bradley, D. A.

    2017-11-01

    World-wide, on-going intensive research is being seen in adaptation of carbon nanotubes (CNTs) for a wide variety of applications, particular interest herein being in the thermoluminescent (TL) properties of CNTs and their sensitivity towards energetic radiations. Using beta radiation delivering dose levels of a few Gy it has been observed in previous study that strain and impurity defects in CNTs give rise to significant TL yields, providing an initial measure of the extent to which electron trapping centres exist in various qualities of CNT, from super-pure to raw. This in turn points to the possibility that there may be considerable advantage in using such media for radiation dosimetry applications, including for in vivo dosimetry. CNTs also have an effective atomic number similar to that of adipose tissue, making them suitable for soft tissue dosimetry. In present investigations various single-wall carbon nanotubes (SWCNT) samples in the form of buckypaper have been irradiated to doses in the range 35-1.3 Gy, use being made of a 90Sr beta source, the response of the CNTs buckypaper with dose showing a trend towards linearity. It is shown for present production methodology for buckypaper samples that the raw SWCNT buckypaper offer the greatest sensitivity, detecting doses down to some few tens of mGy.

  1. Experiences with alanine dosimetry in afterloading brachytherapy

    International Nuclear Information System (INIS)

    Eberhardt, H.-J.; Gohs, U.

    1996-01-01

    At the present, the most commonly used dosimetry for radiotherapy applications are ionisation chambers and thermoluminescent dosimeters (TLD). However, there are some undesirable characteristics of these dosimetry systems, such as large detection volume (ionisation chamber) as well as fading of the radiation induced signal with time and destructive readout (TLG). The present study is an investigation into the use of the alanine/ESR dosimetry in fractionated afterloading brachytherapy during the whole radiotherapy course. There are some qualities which make alanine dosimetry attractive. These are the linear energy response, low fading under standard conditions, and the nondestructive readout. Thus the alanine dosimetry makes possible cumulative dose measurements during the radiotherapy course and an archival storage. By ionizing radiation (gamma, e, n, p, charged particles) free radicals (unpaired electrons) are produced in the amino acid alanine. The continuous wave electron spin resonance (ESR) spectroscopy is used to determine the number of free radicals, which is proportional to the absorbed dose and the alanine content of the dosimeter. The ESR measurements were made at room temperature using a Bruker EPR analyzer EMS-104. The dosimeters used in the test are alanine pellets (23.72 mg weight, 4.9 mm diameter, 1 mm height) as well as flexible alanine film dosimeters (thickness about 500 μm). The dosimeters consist of a blend of L-alpha-alanine and a binder. The alanine content of the pellets and the film dosimeters is about 88 % and 50 % by weight, respectively. The dosimeters for the calculation of the dose-effect-relationship were irradiated at the Physical-Technical Bundesanstalt in Braunschweig by a standard 60Co source. The maximum deviation from the calculated linear function is about 0.12 Gy in the dose range up to 80 Gy. The goal of medical applications was the superficial dose measurement in afterloading brachytherapy during the radiotherapy course in

  2. High-dose dosimetry using natural silicate minerals

    International Nuclear Information System (INIS)

    Carmo, Lucas S. do; Mendes, Leticia; Watanabe, Shigueo; Rao, Gundu; Lucas, Natasha; Sato, Karina; Barbosa, Renata F.

    2015-01-01

    In the present study, certain natural silicate minerals such as aquamarine (AB), morganite (PB), goshenite (WB), white jadeite (JW), green jadeite (JG), pink tourmaline (PT) and two varieties of jadeite-like quartz, denoted here by JQ1 and JQ2, were investigated using the thermoluminescence technique to evaluate their potential for use as very-high- and high-dose dosimeters. These minerals respond to high doses of γ-rays of up to 1000 kGy and often to very high doses of up to 3000 kGy. The TL response of these minerals may be considered to be satisfactory for applications in high-dose dosimetry. Investigations of electron paramagnetic resonance and optically stimulated luminescence dosimetry are in progress. (author)

  3. High-dose dosimetry using natural silicate minerals

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Lucas S. do; Mendes, Leticia, E-mail: isatiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Watanabe, Shigueo; Rao, Gundu; Lucas, Natasha; Sato, Karina, E-mail: lacifid@if.usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Fisica. Departamento de Fisica Nuclear; Barbosa, Renata F., E-mail: profcelta@hotmail.com [Universidade Federal de Sao Paulo (UNIFESP), Santos, SP (Brazil). Departamento de Ciencias do Mar

    2015-07-01

    In the present study, certain natural silicate minerals such as aquamarine (AB), morganite (PB), goshenite (WB), white jadeite (JW), green jadeite (JG), pink tourmaline (PT) and two varieties of jadeite-like quartz, denoted here by JQ1 and JQ2, were investigated using the thermoluminescence technique to evaluate their potential for use as very-high- and high-dose dosimeters. These minerals respond to high doses of γ-rays of up to 1000 kGy and often to very high doses of up to 3000 kGy. The TL response of these minerals may be considered to be satisfactory for applications in high-dose dosimetry. Investigations of electron paramagnetic resonance and optically stimulated luminescence dosimetry are in progress. (author)

  4. Perspex in the verification routines for accelerator beam; El Perspex en las rutinas de verificacion del haz en un acelerador

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Genis S, R. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico D.F. (Mexico)

    1998-12-31

    It is analyzed the use of a perspex solid phantom, adequately referred to a water phantom, as an auxiliary alternative for the daily stability verification routines or constance of radiation beam, as an option in the case of radiotherapy installations with high charge of accelerator working and with basic dosimetry equipment. (Author)

  5. Dosimetry methods in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G.; Artuso, E.; Felisi, M.; Regazzoni, V.; Giove, D. [Universita degli Studi di Milano, Department of Physics, Via Festa del Patrono 7, 20122 Milano (Italy); Agosteo, S.; Barcaglioni, L. [Istituto Nazionale di Fisica Nucleare, Milano (Italy); Campi, F.; Garlati, L. [Politecnico di Milano, Energy Department, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy); De Errico, F. [Universita degli Studi di Pisa, Department of Civil and Industrial Engineering, Lungamo Pacinotti 43, 56126 Pisa (Italy); Borroni, M.; Carrara, M. [Fondazione IRCCS Istituto Nazionale Tumori, Medical Physics Unit, Via Venezian 1, 20133 Milano (Italy); Burian, J.; Klupak, V.; Viererbl, L.; Marek, M. [Research Centre Rez, Department of Neutron Physics, 250-68 Husinec-Rez (Czech Republic)

    2014-08-15

    Dosimetry studies have been carried out at thermal and epithermal columns of Lvr-15 research reactor for investigating the spatial distribution of gamma dose, fast neutron dose and thermal neutron fluence. Two different dosimetry methods, both based on solid state detectors, have been studied and applied and the accuracy and consistency of the results have been inspected. One method is based on Fricke gel dosimeters that are dilute water solutions and have good tissue equivalence for neutrons and also for all the secondary radiations produced by neutron interactions in tissue or water phantoms. Fricke gel dosimeters give the possibility of separating the various dose contributions, i.e. the gamma dose, the fast neutron dose and the dose due to charged particles generated during thermal neutron reactions by isotopes having high cross section, like 10-B. From this last dose, thermal neutron fluence can be obtained by means of the kerma factor. The second method is based on thermoluminescence dosimeters. In particular, the developed method draw advantage from the different heights of the peaks of the glow curve of such phosphors when irradiated with photons or with thermal neutrons. The results show that satisfactory results can be obtained with simple methods, in spite of the complexity of the subject. However, the more suitable dosimeters and principally their utilization and analysis modalities are different for the various neutron beams, mainly depending on the relative intensities of the three components of the neutron field, in particular are different for thermal and epithermal columns. (Author)

  6. Dosimetry methods in boron neutron capture therapy

    International Nuclear Information System (INIS)

    Gambarini, G.; Artuso, E.; Felisi, M.; Regazzoni, V.; Giove, D.; Agosteo, S.; Barcaglioni, L.; Campi, F.; Garlati, L.; De Errico, F.; Borroni, M.; Carrara, M.; Burian, J.; Klupak, V.; Viererbl, L.; Marek, M.

    2014-08-01

    Dosimetry studies have been carried out at thermal and epithermal columns of Lvr-15 research reactor for investigating the spatial distribution of gamma dose, fast neutron dose and thermal neutron fluence. Two different dosimetry methods, both based on solid state detectors, have been studied and applied and the accuracy and consistency of the results have been inspected. One method is based on Fricke gel dosimeters that are dilute water solutions and have good tissue equivalence for neutrons and also for all the secondary radiations produced by neutron interactions in tissue or water phantoms. Fricke gel dosimeters give the possibility of separating the various dose contributions, i.e. the gamma dose, the fast neutron dose and the dose due to charged particles generated during thermal neutron reactions by isotopes having high cross section, like 10-B. From this last dose, thermal neutron fluence can be obtained by means of the kerma factor. The second method is based on thermoluminescence dosimeters. In particular, the developed method draw advantage from the different heights of the peaks of the glow curve of such phosphors when irradiated with photons or with thermal neutrons. The results show that satisfactory results can be obtained with simple methods, in spite of the complexity of the subject. However, the more suitable dosimeters and principally their utilization and analysis modalities are different for the various neutron beams, mainly depending on the relative intensities of the three components of the neutron field, in particular are different for thermal and epithermal columns. (Author)

  7. Improving TL dosimetry for external radiotherapy

    International Nuclear Information System (INIS)

    Bustos, S.R.; Velez, G.; Rubio, M.

    1998-01-01

    Full text: In vivo thermoluminescence dosimetry (TLD) has always been one of the most accurate dosimetry method for external radiotherapy control, but the delay in the response is a well know drawback when it is applied. In this work we show some improvements and demonstrate that keeping the precision and accuracy of this technique, it is possible to obtain a response in few hours. Harshaw 4000 TL reader and LiF TLD-100 dosimeters, chips (3,1 x 3,1 x 0,9 mm 3 ) and rods (1 x 1 x 6 mm 3 ) have been used. The thermal treatment necessary to reuse the TLD is only 1h at 400 degree C, by using a glow curve analyser developed at the Ciemat (Spain), that allows a complete, prompt and precise identification of the individuals peaks. The dosimeters are periodically and individually calibrated. We also have study the factors contributing to the relation TL-dose like linearity, energy correction, directional response and fading. All those results are included into an Excel worksheet which automatically give us the dose resulting from the TL reading (peaks areas 4 and 5). The obtained uncertainty is better than 5%. The TLD already irradiated in radiotherapy institutions distant 30-40 Km from our centre can be read and analysed in about 3-4 hours. These facts render our methods rapid and allow a better control of radiotherapy treatment even if it is bi-fractionated. (author) [es

  8. Thermoluminescence dosemeter for personal dose equivalent assessment

    International Nuclear Information System (INIS)

    Silva, T.A. da; Rosa, L.A.R. da; Campos, L.L.

    1995-01-01

    The possibility was investigated of utilising a Brazilian thermoluminescence individual dosemeter, usually calibrated in terms of photon dose equivalent, for the assessment of the personal dose equivalent, H p (d), at depths of 0.07 and 10 mm. The dosemeter uses four CaSO 4 :Dy thermoluminescent detectors, between different filters, as the sensitive materials. It was calibrated in gamma and X radiation fields in the energy range from 17 to 1250 keV. Linear combinations of the responses of three detectors, in this energy range, allow the evaluation of H p (0.07) and H p (10), for radiation incidence angles varying from 0 to 60 degrees, with an accuracy better than 35%. The method is not applicable to mixed photon-beta fields. (author)

  9. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  10. Calibration of thermoluminescence skin dosemeter response to beta emitters found in Ontario Hydro nuclear power stations

    International Nuclear Information System (INIS)

    Walsh, M.L.; Agnew, D.A.; Donnelly, K.E.

    1984-01-01

    The response of the Ontario Hydro Thermoluminescence Dosimetry System to beta radiation in nuclear power station environments was evaluated. Synthetic beta spectra were constructed, based on activity samples from heat transport systems and fuelling machine contamination smears at nuclear power stations. Using these spectra and dosemeter energy response functions, an overall response factor for the skin dosemeter relative to skin dose at 7 mg.cm -2 was calculated. This calculation was done assuming three specific geometries: (1) an infinite uniformly contaminated plane source at a distance of 33 cm (50 mg.cm -2 total shielding) from the receptor; (2) an infinite cloud surrounding the receptor; (3) a point source at 33 cm. Based on these calculations, a conservative response factor of 0.7 has been chosen. This provides an equation for skin dose assignment, i.e. Skin Dose = 1.4 x Skin Dosemeter Reading when the skin dosemeter is directly calibrated in mGy(gamma). (author)

  11. Thermoluminescence dating of a tephra level from Baume Moula-Guercy (Soyons, Ardeche, France)

    International Nuclear Information System (INIS)

    Sanzelle, S.; Montret, M.; Pilleyre, T.; Miallier, D.; Fain, J.

    1998-01-01

    The Baume Moula-Guercy site (Ardeche, France) is a cave that overhangs the Rhone river valley at a hundred meters height. Since its discovery, it has been assimilated as a shelter with an upper part opened towards the sky. It contains an upper Pleistocene sequence inside which a 2-3 cm localized volcanic layer has been identified. This layer is attributed to an important phreato-magmatic emission from the Vivarais region located at about 50 km SW of the site. The filling of this cave contains neanderthalian remains in a lower level and middle Paleolithic lithic industries in a upper level. Thus, the dating of the tephra level would be of great archaeological importance as it could be used as a chronostratigraphic reference. An estimation of the age obtained by thermoluminescence dating has been requested. This report presents the dating procedure performed on quartz samples extracted from the tephra level and the estimation of the site dosimetry. (J.S.)

  12. Dosimetric characteristics of ultraviolet and x-ray-irradiated KBr:Eu2+ thermoluminescence crystals

    International Nuclear Information System (INIS)

    Melendrez, R.; Perez-Salas, R.; Aceves, R.; Piters, T.M.; Barboza-Flores, M.

    1996-01-01

    Thermoluminescence (TL) characteristics of KBr:Eu 2+ (150 ppm) previously exposed to ultraviolet (UV) light (200 endash 300 nm) and x-ray radiation at room temperature have been determined. The TL glow curve of UV-irradiated samples is composed of six peaks located at 337, 384, 402, 435, 475, and 510 K. The TL glow curves of x-irradiated samples show mainly a TL peak around 384 K. The TL intensities of UV-irradiated (402 and 510 K glow peaks) and x-irradiated specimens present a linear dependence as a function of radiation dose as well as fading stability 300 s after irradiation. These results further enhance the possibilities of using europium-doped materials in nonionizing (actinic region) and ionizing radiation detection and dosimetry applications. copyright 1996 American Institute of Physics

  13. A pocket type thermoluminescent personnel dosimeter

    International Nuclear Information System (INIS)

    Vora, K.G.; Nagpal, J.S.; Pendurkar, H.K.; Gangadharan, P.

    1979-01-01

    A pocket type thermoluminescent personnel dosemeter using CaSO 4 : Dy phosphor is described. Two glass capillaries containing the phosphor are fitted into a plastic tube and covered by a cylindrical filter. The combination is fitted into an ink barrel of a fountain pen. The response of this Dy glass dosimeter was studied for various incident photon energies. A uniform response over the energy range from 33 keV to 1250 keV is achieved. (A.K.)

  14. Phosphor for thermoluminescent type radiation dosimeter

    International Nuclear Information System (INIS)

    Nada, N.; Yamashita, T.

    1975-01-01

    This has the accumulation effect of radiation energy and is mainly used as the element for thermoluminescent type radiation dosimeters. It has as the principal constituent a phosphor consisting of calcium sulfate as the principal constituent and other impurity elements such as dysprosium, thulium and the like. It is more sensitive by the order of 1 to 2 or more figures than the conventional ones and is excellent in the retention of absorbed radiation energy. (U.S.)

  15. Needle-type differential thermoluminescent dosemeter

    International Nuclear Information System (INIS)

    Kubu, M.

    1988-01-01

    The dosemeter serves to measure the depth distribution of absorbed dose in a phantom in mixed neutron and gamma radiation fields. It consists of a stratified cylindrical absorber in which alternate moderator and cadmium layers. Inside are two bores along the longitudinal axis for tubes filled with 6 LiF and 7 LiF powder thermoluminescent dosemeters. The device is easily portable and allows to carry out measurements with a high level of reproducibility. (J.B.). 4 figs

  16. Method of preparing a thermoluminescent phosphor

    Science.gov (United States)

    Lasky, Jerome B.; Moran, Paul R.

    1979-01-01

    A thermoluminescent phosphor comprising LiF doped with boron and magnesium is produced by diffusion of boron into a conventional LiF phosphor doped with magnesium. Where the boron dopant is made to penetrate only the outer layer of the phosphor, it can be used to detect shallowly penetrating radiation such as tritium beta ays in the presence of a background of more penetrating radiation.

  17. Internal sources dosimetry

    International Nuclear Information System (INIS)

    Savio, Eduardo

    1994-01-01

    The absorbed dose, need of estimation in risk evaluation in the application of radiopharmaceuticals in Nuclear Medicine practice,internal dosimetry,internal and external sources. Calculation methodology,Marinelli model,MIRD system for absorbed dose calculation based on biological parameters of radiopharmaceutical in human body or individual,energy of emitted radiations by administered radionuclide, fraction of emitted energy that is absorbed by target body.Limitation of the MIRD calculation model. A explanation of Marinelli method of dosimetry calculation,β dosimetry. Y dosimetry, effective dose, calculation in organs and tissues, examples. Bibliography .

  18. Synthesis and thermoluminescent characterization of lithium niobate doped with erbium

    International Nuclear Information System (INIS)

    Landavazo, M.; Brown, F.; Cubillas, F.; Munoz, I.; Cruz Z, E.

    2015-10-01

    Full text: Lithium niobate (Nl) is a synthetic dielectric and is mainly used in optical devices. There are reports on the thermoluminescent property of Nl monocrystals doped with rare earths and excited with X and gamma rays. In this study the Nl was synthesized and doped with erbium (Er) at concentrations of 1, 2 and 4 % mol and was characterized by its Tl property. The synthesis was realized by solid state reaction at 1000 degrees C for 22 hours and the formation of Nl:Er was confirmed by X-ray diffraction, scanning electron microscopy and EDS analysis, finding a new phase (ErNbO 4 ). Was studied the dose-response gamma in a range of 1-1000 Gy, the material showed linear behavior of 1-600 Gy. The brightness curves have maxima at 185 and 285 degrees C to 1% in 183 and 301 degrees C for 2%, respectively. While for the concentration of 4% a maximum in 177 degrees C accompanied by a smaller peak at higher temperature of the glow curve was observed. The Tl response of Nl:Er 4% to 450 Gy was increased 271 times compared to pure Nl. The reproducibility of the Tl signal at ten cycles of irradiation-reading, present a standard deviation of 5%. In Nl:Er 1% Tl signal fades in 21.3% after 24 hours, while in 2 and 4% an unusual fading occurs. The Tl characteristics of Nl:Er synthesized material is of interest to gamma radiation dosimetry of high doses. (Author)

  19. Modulation of the thermoluminescence glow curve of sol-gel synthesized SiO{sub 2} and Si O-2:Eu through thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Salas J, Ch. J.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R. [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico); Castano, V. M., E-mail: salasjuarez@gimmunison.com [UNAM, Centro de Fisica Aplicada y Tecnologia Avanzada, Apdo. Postal 1-1010, 76000 Queretaro, Qro. (Mexico)

    2015-10-15

    Full text: Due to the increasing use of ionizing radiations, is necessary to monitor the radiation fields and exposure doses in facilities in which they are used. Different facilities or applications involve the use of different radiation and doses, and the sort of needed dosimetry also varies. Sometimes a conventional thermoluminescence (Tl) dosimetry satisfy the requirements since the record of the accumulated dose in a time interval is enough, but other cases could require for real-time measurement of a radiation field, being required a non-Tl dosimetric technique. On the other hand, different applications involve the use of different dose ranges, and so dosimeters with different sensitivities are needed. To solve the diverse needs of radiation detectors and dosimeters, a lot of phosphors materials has been characterized concerning their dosimetric capabilities. For medical application, biocompatible materials are desirable. In this work, we present experimental evidence that Sol-Gel synthesized SiO{sub 2} and SiO{sub 2}:Eu phosphors exhibit Tl glow curves composed by the superposition of several individual glow peaks each located at different temperature ranging from values below 100 up to temperatures greater than 400 degrees C, whose relative sensitivities can be modified by subjecting the phosphors to different thermal annealing. By modulating the relative intensities of the individual Tl peaks, glow curves with different shapes are obtained in such a way that SiO{sub 2} and SiO{sub 2}:Eu can be used to develop dosimeters useful for different dose ranges, and for both, conventional thermoluminescence dosimetry and non-thermoluminescence afterglow-based) dosimetry. (Author)

  20. Modulation of the thermoluminescence glow curve of sol-gel synthesized SiO2 and Si O-2:Eu through thermal annealing

    International Nuclear Information System (INIS)

    Salas J, Ch. J.; Cruz V, C.; Bernal, R.; Castano, V. M.

    2015-10-01

    Full text: Due to the increasing use of ionizing radiations, is necessary to monitor the radiation fields and exposure doses in facilities in which they are used. Different facilities or applications involve the use of different radiation and doses, and the sort of needed dosimetry also varies. Sometimes a conventional thermoluminescence (Tl) dosimetry satisfy the requirements since the record of the accumulated dose in a time interval is enough, but other cases could require for real-time measurement of a radiation field, being required a non-Tl dosimetric technique. On the other hand, different applications involve the use of different dose ranges, and so dosimeters with different sensitivities are needed. To solve the diverse needs of radiation detectors and dosimeters, a lot of phosphors materials has been characterized concerning their dosimetric capabilities. For medical application, biocompatible materials are desirable. In this work, we present experimental evidence that Sol-Gel synthesized SiO 2 and SiO 2 :Eu phosphors exhibit Tl glow curves composed by the superposition of several individual glow peaks each located at different temperature ranging from values below 100 up to temperatures greater than 400 degrees C, whose relative sensitivities can be modified by subjecting the phosphors to different thermal annealing. By modulating the relative intensities of the individual Tl peaks, glow curves with different shapes are obtained in such a way that SiO 2 and SiO 2 :Eu can be used to develop dosimeters useful for different dose ranges, and for both, conventional thermoluminescence dosimetry and non-thermoluminescence afterglow-based) dosimetry. (Author)