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Sample records for thermoluminescent dosemeters tld100

  1. 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

  2. Relative thermoluminescent efficiencies proton/gamma and helium/gamma of high temperature peaks in TLD-100 dosemeters

    International Nuclear Information System (INIS)

    Flores M, E.; Avila, O.; Rodriguez V, M.; Massillon, J.L.G.; Buenfil A, E.; Ruiz T, C.; Brandan, M.E.; Gamboa De Buen, I.

    2007-01-01

    This work presents measures of relative thermoluminescent efficiency of those high temperature peaks of TLD-100 dosemeters exposed to protons of 1.5 MeV and to helium nuclei of 3 and 7.5 MeV. A rigorous reading and of deconvolution protocol was used for the calculation of the TL efficiencies. Additionally an Excel program that facilitated the deconvolution adjustment process of the glow curves was elaborated. (Author)

  3. 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)

  4. Relative thermoluminescent efficiencies proton/gamma and helium/gamma of peaks of high temperature in TLD-100 dosemeters

    International Nuclear Information System (INIS)

    Flores M, E.

    2007-01-01

    The increase of the applications of ion beams in radiotherapy treatments has generated interest in the study of the thermoluminescent materials (TL) that allow to determine the applied doses. A way to quantify the TL response from these materials to ions is by means of the relative thermoluminescent efficiency. In the group of Thermoluminescent dosimetry of the Institute of Physics of the UNAM (IFUNAM) the thermoluminescent response of the TLD-100 dosemeters has been studied, which present a glow curve characteristic with several peaks that correspond to traps and luminescent centers in the material. The stable peaks know each other as 4, 5, 6a, 6b, 7, 8, 9 and 10. The efficiencies should be measured using the response so much to the radiation of interest (in this case protons and helium ions) as the response to gamma radiation. In previous works with ions of low energy taken place in the Pelletron accelerator of the IFUNAM was only measured the TL efficiency for the peak 5 and the total signal. It had not been possible to measure the efficiency of the peaks of high temperature (6a-10) because, for the gamma radiation, the peaks of high temperature show very small signals; however, recently Massillon carries out measures of efficiency TL of peaks of high temperature for ions of intermediate energy using a protocol special of reading and of deconvolution that allows to measure the signals coming from the peaks of high temperature. In this work is implemented this same protocol to complete the study of TL efficiencies at low energy of protons and helium and to determine if the values of efficiency depend on the used reading protocol. For it is reported it measures of the relative efficiency of the peaks of high temperature from the TLD-100 exposed to protons of 1.5 MeV and nuclei of helium of 3 and 7.5 MeV. (Author)

  5. Relative thermoluminescent efficiencies proton/gamma and helium/gamma of high temperature peaks in TLD-100 dosemeters; Eficiencias termoluminiscentes relativas proton/gamma y helio/gamma de picos de alta temperatura en dosimetros TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Flores M, E.; Avila, O.; Rodriguez V, M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico); Massillon, J.L.G.; Buenfil A, E.; Ruiz T, C.; Brandan, M.E. [IFUNAM, 04500 Mexico D.F. (Mexico); Gamboa De Buen, I. [ICN-UNAM, 04500 Mexico D.F. (Mexico)

    2007-07-01

    This work presents measures of relative thermoluminescent efficiency of those high temperature peaks of TLD-100 dosemeters exposed to protons of 1.5 MeV and to helium nuclei of 3 and 7.5 MeV. A rigorous reading and of deconvolution protocol was used for the calculation of the TL efficiencies. Additionally an Excel program that facilitated the deconvolution adjustment process of the glow curves was elaborated. (Author)

  6. Thermoluminescent response of dosemeters TLD-100 exposed to distinct baker protocols, irradiation and reading; Respuesta termoluminiscente de dosimetros TLD-100 sujetos a distintos protocolos de horneado, irradiacion y lectura

    Energy Technology Data Exchange (ETDEWEB)

    Estrada E, D

    2002-07-01

    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 ({eta}{sub PCP}, {gamma}) 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 {eta}{sub PCP}, {gamma} 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 {sup 60}Co ({eta}{sub PCP}, {gamma}), varying the lot, the presentation, the one baked and the team reader. When was used the same global procedure values they were obtained for ({eta}{sub PCP}, {gamma}) 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 ({eta}{sub PCP}, {gamma}) 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{sup 10} p/cm{sup 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

  7. Relative thermoluminescent efficiencies proton/gamma and helium/gamma of peaks of high temperature in TLD-100 dosemeters; Eficiencias termoluminiscentes relativas proton/gamma y helio/gamma de picos de alta temperatura en dosimetros TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Flores M, E. [UNAM, Facultad de Ciencias, 04510 Mexico D.F. (Mexico)

    2007-07-01

    The increase of the applications of ion beams in radiotherapy treatments has generated interest in the study of the thermoluminescent materials (TL) that allow to determine the applied doses. A way to quantify the TL response from these materials to ions is by means of the relative thermoluminescent efficiency. In the group of Thermoluminescent dosimetry of the Institute of Physics of the UNAM (IFUNAM) the thermoluminescent response of the TLD-100 dosemeters has been studied, which present a glow curve characteristic with several peaks that correspond to traps and luminescent centers in the material. The stable peaks know each other as 4, 5, 6a, 6b, 7, 8, 9 and 10. The efficiencies should be measured using the response so much to the radiation of interest (in this case protons and helium ions) as the response to gamma radiation. In previous works with ions of low energy taken place in the Pelletron accelerator of the IFUNAM was only measured the TL efficiency for the peak 5 and the total signal. It had not been possible to measure the efficiency of the peaks of high temperature (6a-10) because, for the gamma radiation, the peaks of high temperature show very small signals; however, recently Massillon carries out measures of efficiency TL of peaks of high temperature for ions of intermediate energy using a protocol special of reading and of deconvolution that allows to measure the signals coming from the peaks of high temperature. In this work is implemented this same protocol to complete the study of TL efficiencies at low energy of protons and helium and to determine if the values of efficiency depend on the used reading protocol. For it is reported it measures of the relative efficiency of the peaks of high temperature from the TLD-100 exposed to protons of 1.5 MeV and nuclei of helium of 3 and 7.5 MeV. (Author)

  8. Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation

    International Nuclear Information System (INIS)

    Concha S, K.; Avila, O.; Gamboa de Buen, I.; Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E.

    2004-01-01

    The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of 60 Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E 1 energy (4.8 MeV) and E 2 (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

  9. Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation; Eficiencias termoluminiscentes relativas de TLD-100 para iones de nitrogeno respecto de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Concha S, K. [UNAM, Facultad de Ciencias, 04510 Mexico D.F. (Mexico); Avila, O. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Gamboa de Buen, I. [ICN-UNAM, 04510 Mexico D.F. (Mexico); Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E. [IFUNAM, 04510 Mexico D.F. (Mexico)

    2004-07-01

    The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of {sup 60} Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E{sub 1} energy (4.8 MeV) and E{sub 2} (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

  10. Thermoluminescence and optical absorption comparative studies with TLD-100 and pure LiF

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da; Caldas, L.V.E.

    1988-07-01

    Optical absorption (OA) studies were carried out with LiF: Mg, Ti (TLD-100) and pure LiF exposed to X radiation, 77.4 C.kg -1 (3 x 10 5 R) with the aim of relating the thermoluminescent (TL) peaks presented by TLD-100 to its intrinsic and irradiation defects. After a 280 0 C thermal treatment for 15 minutes, an absorption band at 225 nm is observed in the TLD-100 OA spectrum. This band is not observed in the case of pure LiF. A correlation between TL peak 5 and the absorption band at 310 nm is established for TLD-100. These results agree with other publications and are explained. (author) [pt

  11. 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

  12. Thermoluminescence of pure LiF and Lif (TLD-100) irradiated at room temperature

    International Nuclear Information System (INIS)

    Sagastibelza Chivite, F.

    1980-01-01

    The thermoluminescence of pure LiF and LiF (TLD-100) crystals irradiated at room temperature with x - or gamma-rays has been studied up to 460 degree centigree. For most of the glow peaks found the kinetics, preexponential factors and activation energies have been determined. These parameters have been obtained by means of the isothermal method. The study of the thermal annealing of the radiation induced F and Z centres has allow to show that there is a correlation among the glow peaks and the annealing stages of these centres. It is concluded that the F and Z - centres play the role of recombination centres for halogen interstitial atom thermally released from traps. Light emission occurs in this recombination. (Author) 120 refs

  13. Experimental calibration and determination of the relative response for Lif: Mg, Ti(TLD-100) dosemeters at 60Co gamma and 60 kVp X-ray energies

    International Nuclear Information System (INIS)

    Marco, M.L.; Gonzalez, L.; Delgado, V.; Vano, E.; Moran, P.

    1985-01-01

    The thermoluminescence efficiency of LiF: Mg, Ti (TLD-100) dosemeters has been determined for photon beams from 60 Co gamma rays and 60 kVp X-rays. It has been proven that light yield varies as a function of the photon energy. An experiment was performed using an X-ray beam whose spectrum has been determined by an X-ray fluorescence method. This enabled a direct calculation of the absorbed doses in the T1 material for the different operation conditions. These values and the experimental ones from measuring T1 intensities have been used to obtain the efficiency for energy X-ray spectrum. From the above values, the dosemeter T1 response, relative to 60 Co, has been evaluated. (author)

  14. Dosimetric evaluation of the response of the TLD-100 dosemeters in the IMRT technique by 'Step and Shoot'

    International Nuclear Information System (INIS)

    Vasquez, J.; Benavides, S.O.

    2005-01-01

    We show the results of the dosimetry response of LiF thermoluminescent crystals: TLD-100, where they were radiated in a linear accelerator Siemens Primus Hl using the Intensity Modulated Radiation Therapy (IMRT) by step and shoot technique. Previous to the crystals calibration and response evaluation, the acceptation procedures recommended by the TG-53 protocol for validation of the technique were carried out. The planning system utilized was the Theraplan Plus 3.8, using the algorithm of Pencil Kernel. The register and verification system was Lantis 5.2. The response curve of dose versus charge was obtained from the readings of the TLD in a Harshaw 3500. The crystals were radiated in a Bench- Marck phantom with doses previously determined by using ionization chambers for square radiation fields, in a beam with a 0.68 TPR20,10 corresponding to 6 MV of energy. We compare the response of these through of radiation of segmented fields in a Anthropomorphic phantom and the calculated doses by the planning system. The results obtained in the crystals response show deviations less than 5 % between the measured dose and the calculated dose in the zones of low gradient. It allows its implementation like routine control of quality by IMRT. (Author)

  15. 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)

  16. 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)

  17. Proton/gamma relative thermoluminescence efficiencies of LiF:Mg,Cu,P+PTFE prepared at ININ and TLD-100H

    Energy Technology Data Exchange (ETDEWEB)

    Avila, O.; Gonzalez, P.; Murillo, G. [Departamento de Fisica, ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico)

    2009-10-15

    Properties of LiF:Mg,Cu,P+PTFE dosemeters developed at ININ have been investigated in order to evaluate their performance compared to those of equivalent commercial dosemeters. In this work both LiF:Mg,Cu,P+PTFE and TLD-100H pellets were exposed to low fluence 3 MeV protons and to low dose gamma radiation to evaluate experimental proton/gamma efficiencies. Gamma irradiation was performed using the Vic krad irradiator at ININ at varying doses between 25 and 500 mGy. For proton irradiation the Tandem Van de Graaff accelerator at ININ was used. Dosemeters were placed on a holder inside a scattering chamber where protons impinge on a gold target and scatter in all directions. The holder allows for several angular positions so that dosemeters receive proton fluence between 10{sup 6} and 10{sup 1}0 p/cm{sup 2}. Experimental efficiency values found for LiF:Mg,Cu,P+PTFE and TLD-100H were 0.18 +- 03 and 0.23 +- 0.03, respectively. These results allow to confirm the reliability of the dosemeters developed at ININ. (Author)

  18. Proton/gamma relative thermoluminescence efficiencies of LiF:Mg,Cu,P+PTFE prepared at ININ and TLD-100H

    International Nuclear Information System (INIS)

    Avila, O.; Gonzalez, P.; Murillo, G.

    2009-10-01

    Properties of LiF:Mg,Cu,P+PTFE dosemeters developed at ININ have been investigated in order to evaluate their performance compared to those of equivalent commercial dosemeters. In this work both LiF:Mg,Cu,P+PTFE and TLD-100H pellets were exposed to low fluence 3 MeV protons and to low dose gamma radiation to evaluate experimental proton/gamma efficiencies. Gamma irradiation was performed using the Vic krad irradiator at ININ at varying doses between 25 and 500 mGy. For proton irradiation the Tandem Van de Graaff accelerator at ININ was used. Dosemeters were placed on a holder inside a scattering chamber where protons impinge on a gold target and scatter in all directions. The holder allows for several angular positions so that dosemeters receive proton fluence between 10 6 and 10 1 0 p/cm 2 . Experimental efficiency values found for LiF:Mg,Cu,P+PTFE and TLD-100H were 0.18 +- 03 and 0.23 +- 0.03, respectively. These results allow to confirm the reliability of the dosemeters developed at ININ. (Author)

  19. Thermoluminescence of pure LiF and Lif (TLD-100) irradiated at room temperature; Termoluminiscencia en LiF puro y LiF dosimetrico (TLD-100), irradiados a temperatura ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Sagastibelza Chivite, F.

    1980-07-01

    The thermoluminescence of pure LiF and LiF (TLD-100) crystals irradiated at room temperature with x - or gamma-rays has been studied up to 460 degree centigree. For most of the glow peaks found the kinetics, preexponential factors and activation energies have been determined. These parameters have been obtained by means of the isothermal method. The study of the thermal annealing of the radiation induced F and Z centres has allow to show that there is a correlation among the glow peaks and the annealing stages of these centres. It is concluded that the F and Z - centres play the role of recombination centres for halogen interstitial atom thermally released from traps. Light emission occurs in this recombination. (Author) 120 refs.

  20. 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

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

    African Journals Online (AJOL)

    As part of efforts to isolate and utilize local and naturally occurring materials for development of thermoluminescece dosemeters and other technologies, an earlier report had shown that Nigerian clay showed prospects of utility as a thermoluminescence dosemeter (TLD). This paper reports the investigation of the basic ...

  2. 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

  3. Al2 O3:Cr,Ni: a possible thermoluminescent dosemeter

    International Nuclear Information System (INIS)

    Mariani R, Francisco; Roman B, Alvaro; Saavedra S, Renato; Ibarra S, Angel

    1996-01-01

    Results from a study on the thermoluminescent (Tl) emission from Al 2 O 3 :Cr,Ni are presented. The measurements were obtained for evaluation of the Al 2 O 3 :Cr,Ni dosimetric properties. Different crystal batches were exposed to two kind of ionizing radiation (X-ray and β - ). The Tl spectrum has a main peak with high thermal and optical stability, deviating from linearity for doses lower than 3.6 Gy. Furthermore, this material shows advantages (thermal resistance, reusability, multiple heating cycles) compared to TLD-100. Measured Al 2 O 3 :Cr,Ni properties indicate that it could be used as a dosemeter. (author)

  4. 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)

  5. Characteristics of thermoluminescent dosemeter and their recent trend

    International Nuclear Information System (INIS)

    Yook, C.C.

    1979-01-01

    Principles, characteristics, and recent trends of application of the thermoluminescent dosemeter are extensively reviewed. The sensitivity, reproducibility, fluctuation range and other practical details are also examined and discussed. (author)

  6. Determination of the TLD-100 physical parameters

    International Nuclear Information System (INIS)

    Paucar J, J.; Picon C, C.

    1998-01-01

    This study was realized in the Physics service at the Radiotherapy Department of the National Institute of Neoplasic Diseases in Lima, Peru, it was determined the activation energy, the kinetic order and the frequency factor of the fifth peak of the TLD-100 thermoluminescent spectra using different algorithms. This was carried out in parallel with the implementation and design of a software and an interface associated with the Tl lecturer which allows a semiautomatic control for a thermoluminescent lecturer process. (Author)

  7. Phototransference in LiF (TLD-100) at low temperatures

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da; Caldas, L.V.E.

    1990-01-01

    Phototransference experiments were performed with UV light of 250, 310 and 380 nm in LiF (TLD-100) at liquid nitrogen temperature with the aim of observing thermoluminescence emission peaks. (A.C.A.S.) [pt

  8. 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)

  9. Determination of the TLD-100 physical parameters; Determinacion de parametros fisicos del TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Paucar J, J.; Picon C, C. [Instituto Nacional de Enfermedades Neoplasicas. INEN. Av. Angamos Este 2520, Lima 34 (Peru)

    1998-12-31

    This study was realized in the Physics service at the Radiotherapy Department of the National Institute of Neoplasic Diseases in Lima, Peru, it was determined the activation energy, the kinetic order and the frequency factor of the fifth peak of the TLD-100 thermoluminescent spectra using different algorithms. This was carried out in parallel with the implementation and design of a software and an interface associated with the Tl lecturer which allows a semiautomatic control for a thermoluminescent lecturer process. (Author)

  10. Dosimetric evaluation of the response of the TLD-100 dosemeters in the IMRT technique by 'Step and Shoot'; Evaluacion dosimetrica de la respuesta de los dosimetros TLD-100 en la tecnica de IMRT por 'Step and Shoot'

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, J. [Fundacion Clinica Valle del Lili, A.A. 020338, Cali (Colombia); Benavides, S.O. [Depto. de Fisica, Universidad del Valle, A.A. 25360, Cali (Colombia)

    2005-07-01

    We show the results of the dosimetry response of LiF thermoluminescent crystals: TLD-100, where they were radiated in a linear accelerator Siemens Primus Hl using the Intensity Modulated Radiation Therapy (IMRT) by step and shoot technique. Previous to the crystals calibration and response evaluation, the acceptation procedures recommended by the TG-53 protocol for validation of the technique were carried out. The planning system utilized was the Theraplan Plus 3.8, using the algorithm of Pencil Kernel. The register and verification system was Lantis 5.2. The response curve of dose versus charge was obtained from the readings of the TLD in a Harshaw 3500. The crystals were radiated in a Bench- Marck phantom with doses previously determined by using ionization chambers for square radiation fields, in a beam with a 0.68 TPR20,10 corresponding to 6 MV of energy. We compare the response of these through of radiation of segmented fields in a Anthropomorphic phantom and the calculated doses by the planning system. The results obtained in the crystals response show deviations less than 5 % between the measured dose and the calculated dose in the zones of low gradient. It allows its implementation like routine control of quality by IMRT. (Author)

  11. 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.

  12. Dosimetric of extremities with Dosemeters thermoluminescent in Cuba

    International Nuclear Information System (INIS)

    Molina Perez, D.; Diaz Bernal, E.; Vera Alonso, L.

    1998-01-01

    From final of the year 1995 in the CPHR implement the service of monitoring of the extremities using Dosemeter thermoluminescent (TL). The dosemeter consists on a metallic ring with a circular hole where a detector of LiF:Mg,Ti is placed (model JR1152C) of 5x5x0.9 mm 3 , covered by a fine layer of polyethylene. In the work the characteristic dosimetric as of the dosemeter is studied it satisfies the main requirements for their use in the monitoring from the exhibition to radiation photonic of the extremities. The doses are also presented registered during the first two years of operation of the service. The results obtained until the moment point out to you practice them of nuclear medicine, radiotherapy and production of substances radioactive how as of more contribution

  13. About the measurements systems with pen and thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Cortes I, M.E.; Ramirez G, F.P.

    1998-01-01

    In this work it is presented dosimetric data obtained with pen and thermoluminescent dosemeters, which are used by the Occupational Exposure Personnel (OEP) of the Mexican Petroleum Institute (IMP)(1). It was marked several great characteristics as for example, the differences among units which use one and another dosemeter type. Likewise, it is given to know diverse problems that were had in the IMP at relating the data obtained with these dosemeters (which utilizes OEP) and the ICRP 60 recommendations 1990. One of the most important difficulties is to satisfy the recommended limits by ICRP, particularly those that are referring to the units and their complex calculations. With respect to the unities, the ICRP makes reference at the concepts 'dose equivalent' and 'effective dose' with the sievert unit, that the General Regulations for Radiological Safety associates with 'dose equivalent' and 'effective dose equivalent'. It was illustrated the type of dosimetric statistics which are obtained with the TLD lectures and a OEP pen dosemeter during 1997. (Author)

  14. Method of making isodose curve using thermoluminescence dosemeter

    International Nuclear Information System (INIS)

    Bakar Ramain, A.

    1975-01-01

    Line source of 60 Co in the form of needles and tubes are extensively used in radiotherapy in moulds, implants, and intracavitary techniques for the treatment of malignant lesions. It is important to have isodose distributions in tissue for those source for purposes of treatment planning. The isodose distributions have been obtained experimentally by using tinny lithium-fluoride (Lsub(i)F) thermoluminescent dosemeters (TLD) and they are compared to the theoretical results. The distinct advantages of Lsub(i)F (TLD) in such measurements are briefly discussed. (author)

  15. TLD-100 and Radiochromic Dye Film in Medical Dosimetry

    International Nuclear Information System (INIS)

    Mercado-Uribe, H.

    2006-01-01

    TLD-100 and radiochromic dye films are two types of the dosimeters most used in the medical physics area. Both are secondary detectors and operate in a different way and in different dose measurement ranges. The use of TLD-100 is based on the thermoluminescent process, and the RDF in the optical density change when has been exposed to an irradiation field previously. In this work it is analyzed in a general way, the advantages and characteristics of these detectors and the reasons of the great increase in their use in the last decades

  16. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative quantities ICRU, for external fields of beta radiation. Part II. I study of the angular response of personal dosemeters TLD-100 in secondary patron fields of beta radiation (90Sr / 90Y)

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1994-01-01

    The objective of this work is to carry out one of the possible ones test type for personal dosemeters TLD, under the recomendations of the ICRU 39, ICRU 43 and the draft of the norm ISO 6980,(1992), with the purpose of verifying the capacity of these detectors to carry out the operative unit: H' (0.07;α). Since H' (O. 07;α) this defined one in an expanded field, one of these tests type consist on determining the angular response of these detectors. 20 personal dosemeters TLD-100 was used, (card marks: Harshaw, Model: G-1, with two glasses of TLD-100 absorbed in teflon; the portadosemeters has two windows, a free one and another with a filter of Pb of 171.0 mg cm -2 ); these dosemeters they were previously selected, [to see, S tudy of the Homogeneity of the response of Personal Dosemeters (Cards G-l, TLD-100) in Radiation of Countrysides of 60 Co , J.T. Alvarez R. Technician Report GSR/IT/0001/94].The irradiations to effectued in secondary countryside of radiation beta of 90 Sr/ 90 Y. The study was undertaken by means of an experimental design of blocks random that contemplate the following variables: intensity of the radiation source, (1850 MBq and 74 MBq); position of irradiation, (four positions); incidence of angle of the radiation (0, 15, 30, 45, 60 and 75 grades) and the absorbed dose in air, (0.005, 0.010, 0.020, 0.050 and 0.100 Gy). Then null hypothesis it was to suppose that there was not difference among the stockings of each treatment, to used the statistical of Duncan to carry out tests of stockings at a level of significance of 5%.These tests of stockings throw the following results in those variables of the experimental design: The irradiations carried out so much with the source pattern secondary of 90 Sr/ 90 Y of 1850 MBq and of 74 MBq, they are equivalent reason why they can be used indistinctly. The responses of each one of the glasses of the card are strongly anisotropic for each glass; four positions of irradiation is used: glass 1 (window of

  17. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative magnitudes ICRU, for external fields of beta radiation. Part I. Study of the homogeneity of the response personal dosemeters leaves (cards G-1, TLD-100), in radiation fields of Co60

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1994-01-01

    A sample of 40 composed personal dosemeters by cards model: G-l, (each card is made up of two TLD-100 crystals encapsulated in teflon), Harshaw trademark; those personal dosemeters present a free window and another with a filter of A1 of 171.7 mg cm -2 of mass thickness.The objective of the work is to select of this sample of 40 personal dosemeters a population with the same stocking and standard deviation. The technique used is that of comparison of stockings, (ANOVA; Variance Analysis, when samples of the same one were had size; and/or GLM, Widespread Lineal Models, when the samples were of different size), by means of the use of those Duncan statistics, SNK, Tukey, Gabriel; the results are validated proving the kindness of adjustment of the experimental data to a Normal distribution by means of the Shapiro-Wilks statistics.The experimental design used consists on a test of two vias: a via is the variable card with two levels, (crystal 1 and 2), the other via is the variable irradiation position with four levels, (LS=left superior, SR= right superior, LI= left Inferior, IR = right inferior). The irradiations carried out in blocks of four personal dosemeters in a gamma radiation beam range of Cobalt 60; carrying out three repetitions of the design. With object of proving the homogeneity of the filter of A1 in those personal dosemeters the experimental design was executed for those cards without personal dosemeters.They were also carried out tests of stockings to the readings of bottom and sensibility of the reader equipment, (Harshaw, model marks 2271), certain that doesn t exist differences for sequence of reading, but if in the stockings of the sensibility, (they were 4 different populations). The responses of the dosemeters were corrected subtracting him the reading correspondence of bottom and by sensibility of the reader equipment before subjecting them to the tests of stockings mentioned. Of the results of the tests of stockings for the cards with and

  18. 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)

  19. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative quantities ICRU, for external fields of beta radiation. Part II. I study of the angular response of personal dosemeters TLD-100 in secondary patron fields of beta radiation ({sup 90}Sr / {sup 90}Y); Medicion de dosis equivalente con dosimetros personales e instrumentos de proteccion radiologica en las nuevas magnitudes operativas ICRU, para campos de radiacion beta externos. Parte II. Estudio de la respuesta angular de dosimetros personales TLD-100 en campos patrones secundarios de radiacion beta ({sup 90}Sr/{sup 90}Y)

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1994-01-15

    The objective of this work is to carry out one of the possible ones test type for personal dosemeters TLD, under the recomendations of the ICRU 39, ICRU 43 and the draft of the norm ISO 6980,(1992), with the purpose of verifying the capacity of these detectors to carry out the operative unit: H' (0.07;{alpha}). Since H' (O. 07;{alpha}) this defined one in an expanded field, one of these tests type consist on determining the angular response of these detectors. 20 personal dosemeters TLD-100 was used, (card marks: Harshaw, Model: G-1, with two glasses of TLD-100 absorbed in teflon; the portadosemeters has two windows, a free one and another with a filter of Pb of 171.0 mg cm{sup -2}); these dosemeters they were previously selected, [to see, {sup S}tudy of the Homogeneity of the response of Personal Dosemeters (Cards G-l, TLD-100) in Radiation of Countrysides of {sup 60}Co{sup ,} J.T. Alvarez R. Technician Report GSR/IT/0001/94].The irradiations to effectued in secondary countryside of radiation beta of {sup 90}Sr/{sup 90}Y. The study was undertaken by means of an experimental design of blocks random that contemplate the following variables: intensity of the radiation source, (1850 MBq and 74 MBq); position of irradiation, (four positions); incidence of angle of the radiation (0, 15, 30, 45, 60 and 75 grades) and the absorbed dose in air, (0.005, 0.010, 0.020, 0.050 and 0.100 Gy). Then null hypothesis it was to suppose that there was not difference among the stockings of each treatment, to used the statistical of Duncan to carry out tests of stockings at a level of significance of 5%.These tests of stockings throw the following results in those variables of the experimental design: The irradiations carried out so much with the source pattern secondary of {sup 90}Sr/{sup 90}Y of 1850 MBq and of 74 MBq, they are equivalent reason why they can be used indistinctly. The responses of each one of the glasses of the card are strongly anisotropic for each glass

  20. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative magnitudes ICRU, for external fields of beta radiation. Part I. Study of the homogeneity of the response personal dosemeters leaves (cards G-1, TLD-100), in radiation fields of Co{sub 60}; Medicion de dosis equivalente con dosimetros personales e instrumentos de proteccion radiologica en las nuevas magnitudes operativas ICRU, para campos de radiacion beta externos. Parte I. Estudio de la homogeneidad de la respuesta dosimetros personales (tarjetas G-1, TLD-100), en campos de radiacion de Co{sub 60}

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1994-01-15

    A sample of 40 composed personal dosemeters by cards model: G-l, (each card is made up of two TLD-100 crystals encapsulated in teflon), Harshaw trademark; those personal dosemeters present a free window and another with a filter of A1 of 171.7 mg cm{sup -2} of mass thickness.The objective of the work is to select of this sample of 40 personal dosemeters a population with the same stocking and standard deviation. The technique used is that of comparison of stockings, (ANOVA; Variance Analysis, when samples of the same one were had size; and/or GLM, Widespread Lineal Models, when the samples were of different size), by means of the use of those Duncan statistics, SNK, Tukey, Gabriel; the results are validated proving the kindness of adjustment of the experimental data to a Normal distribution by means of the Shapiro-Wilks statistics.The experimental design used consists on a test of two vias: a via is the variable card with two levels, (crystal 1 and 2), the other via is the variable irradiation position with four levels, (LS=left superior, SR= right superior, LI= left Inferior, IR = right inferior). The irradiations carried out in blocks of four personal dosemeters in a gamma radiation beam range of Cobalt 60; carrying out three repetitions of the design. With object of proving the homogeneity of the filter of A1 in those personal dosemeters the experimental design was executed for those cards without personal dosemeters.They were also carried out tests of stockings to the readings of bottom and sensibility of the reader equipment, (Harshaw, model marks 2271), certain that doesn{sup t} exist differences for sequence of reading, but if in the stockings of the sensibility, (they were 4 different populations). The responses of the dosemeters were corrected subtracting him the reading correspondence of bottom and by sensibility of the reader equipment before subjecting them to the tests of stockings mentioned. Of the results of the tests of stockings for the cards with

  1. From films to thermoluminescence dosemeters: The Greek Atomic Energy Commission experience

    International Nuclear Information System (INIS)

    The personnel dosimetry department of the Greek Atomic Energy Commission (GAEC) assures the individual monitoring of almost 8000 occupationally exposed workers. Thermoluminescence dosimetry system replaced the existing photographic dosimetry system for the individual monitoring with the joint support of IAEA and GAEC. The thermoluminescence dosimetry system consists of two automated readers, one automated irradiator and about 20,000 dosemeters purchased from the Rados Co. The properties of two thermoluminescent materials have been compared: LiF has been chosen for the whole-body dosemeter configuration and Li 2 B 4 O 7 for the extremities. The technical evaluation of the system has been performed according to the European and IEC standards. The overall uncertainty has been calculated. The existing database system, and the accounting and dispatching procedures have been adapted to the new demands. The system became operational on March 2000, and the official distribution of thermoluminescence dosemeters has begun. (author)

  2. Measurement of doses to aviator pilots using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

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

    2004-01-01

    During the development of their work, the aviator pilots are exposed at high levels of natural radiation of bottom caused mainly by the cosmic radiation of galactic origin and lot. For such reason, the Metropolitan Autonomous University (UAM) and the Union Association of Aviator Pilots (ASPA), subscribed an agreement with the purpose of to measure the doses of ionizing radiation received by the aviator pilots of diverse air companies that man different types of airships and to determine if these doses surpass the one limit of 0.11 mSv/h settled down by the IAEA for the public in general; and if therefore, these workers should be considered as personnel occupationally exposed. In this work the obtained results when measuring the absorbed dose received by Mexican civil aviator pilots during the development of their work, using thermoluminescent dosemeters of LiF:Mg,Cu,P + Ptfe of national production are presented. The obtained results during the years of 2001 and 2002 show that the monthly doses received by the pilots surpass the one it limits established for the public in general, for what they should be considered as personnel occupationally exposed. (Author)

  3. 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)

  4. 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)

  5. Dose profile measurement in computerized axial tomography equipment using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Azorin V, J.C.; Falcony, C.; Azorin N, J.

    2000-01-01

    In this work are presented the results about measuring the radiation dose profile in two equipment of computerized axial tomography (Tac). Thermoluminescent dosemeters (Dtl) of LiF, Mg, Cu, P + Ptfe in form of disks were used which were developed and made in Mexico. The results showed that Dtl are appropriated for these type of studies. (Author)

  6. 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)

  7. Effective dose assessment in the maxillofacial region using thermoluminescent (TLD) and metal oxide semiconductor field-effect transistor (MOSFET) dosemeters: a comparative study

    Science.gov (United States)

    Schulze, D; Wolff, J; Rottke, D

    2014-01-01

    Objectives: The objective of this study was to compare the performance of metal oxide semiconductor field-effect transistor (MOSFET) technology dosemeters with thermoluminescent dosemeters (TLDs) (TLD 100; Thermo Fisher Scientific, Waltham, MA) in the maxillofacial area. Methods: Organ and effective dose measurements were performed using 40 TLD and 20 MOSFET dosemeters that were alternately placed in 20 different locations in 1 anthropomorphic RANDO® head phantom (the Phantom Laboratory, Salem, NY). The phantom was exposed to four different CBCT default maxillofacial protocols using small (4 × 5 cm) to full face (20 × 17 cm) fields of view (FOVs). Results: The TLD effective doses ranged between 7.0 and 158.0 µSv and the MOSFET doses between 6.1 and 175.0 µSv. The MOSFET and TLD effective doses acquired using four different (FOV) protocols were as follows: face maxillofacial (FOV 20 × 17 cm) (MOSFET, 83.4 µSv; TLD, 87.6 µSv; −5%); teeth, upper jaw (FOV, 8.5 × 5.0 cm) (MOSFET, 6.1 µSv; TLD, 7.0 µSv; −14%); tooth, mandible and left molar (FOV, 4 × 5 cm) (MOSFET, 10.3 µSv; TLD, 12.3 µSv; −16%) and teeth, both jaws (FOV, 10 × 10 cm) (MOSFET, 175 µSv; TLD, 158 µSv; +11%). The largest variation in organ and effective dose was recorded in the small FOV protocols. Conclusions: Taking into account the uncertainties of both measurement methods and the results of the statistical analysis, the effective doses acquired using MOSFET dosemeters were found to be in good agreement with those obtained using TLD dosemeters. The MOSFET dosemeters constitute a feasible alternative for TLDs for the effective dose assessment of CBCT devices in the maxillofacial region. PMID:25143020

  8. Response of TLD-100{sup TM} microtubes to two RQR3 quality radiation beams; Resposta de microcubos de TLD-100{sup TM} a dois feixes de qualidade RQR 3

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, M.G.; Villani, D.; Almeida, S.B.; Vivolo, V.; Yoriyaz, H., E-mail: dvillani@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Louis, G.M.J. [Universidad Nacional Autonoma de Mexico (Mexico)

    2016-07-01

    The present work compares the response of TLD-100{sup TM} microcubes to two RQR 3 diagnostic radiology reference quality radiation beams, defined by IEC-61267 norm, aiming to evaluate the detectability of TLD-100{sup TM} energy dependence reported in literature within the same reference quality radiation range. TLD-100{sup TM} microcubes reproducibility is assessed through the response of a second set of TLD-100{sup TM} microcubes, evaluated in a second thermoluminescence reader, to the RQR 3 diagnostic radiology reference quality radiation beam implemented at the Laboratorio de Calibracao de Instrumentos of IPEN, Sao Paulo, SP, Brazil. The dependence of TLD-100{sup TM} microcubes TL response was not detectable in these conditions and the reproducibility of the measurements is 90,2%. (author)

  9. 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)

  10. Thermoluminescent dosemeters of CaSO4: Dy + Teflon

    International Nuclear Information System (INIS)

    Campos, L.L.

    1989-01-01

    The development of a pellet dosemeter of CaSO 4 : Dy + Teflon at the Dosimetric Materials Production Laboratory - IPEN/Brazilian CNEN-SP is presented. The pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. The pellet characteristics from the point of view of dosimetry. 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 three filters allows to determine the energy of an unknown source. (author) [pt

  11. Determination of the dose index in computerized tomography using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Azorin, J.C.; Calderon, A.; Azorin, J.

    2004-01-01

    In this work the obtained results of the determination of the dose index are presented in thorax studies in computed tomography and helical tomography carried out in Mexico using thermoluminescent dosemeters of LiF: Mg,Cu,P + Ptfe developed and manufactured in our country. The results showed that under similar conditions of irradiation and operation (pitch = 1), significant differences don't exist among the doses absorbed measures in the phantom due to the two types of used tomographs. (Author)

  12. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P thermoluminescent dosemeter and its applications in diagnostic radiology

    Energy Technology Data Exchange (ETDEWEB)

    Fung, K.K.L

    2000-12-01

    The recent introduction and development of the thermoluminescent (T.L.) phosphor material LiF:Mg,Cu,P (usually named TLD100H or GR200A) has aroused intense interest of scientists in the field of radiation dosimetry due to its very favourable dosimetric characteristics. Both conventional LiF:Mg,Ti (TLD100) and LiF:Mg,Cu,P T.L. phosphors are tissue-equivalent but GR200A outperforms in respect of its very much higher sensitivity, by a factor of greater than 25, and a dose detection threshold of less than 1 {mu}Gy. A reproducible readout and annealing regime was developed in the initial part of this study with the newly installed automatic TLD (Thermoluminescence Dosimetry) apparatus in the X-ray and Radiation Physics Laboratories of the Hong Kong Polytechnic University. Basic dosimetric characteristics of this T.L. dosemeter (supplied by Harshaw-Bicron Co.) were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. Dosimetric characteristics which included linearity, reproducibility, batch uniformity, energy response, and minimum detectable dose were studied using X-rays in the commonly used diagnostic radiology energy range. Favourable dosimetric characteristics were observed from this T.L. phosphor, which agrees well with published studies. The effect of the number of thermal treatment cycles in the initialisation process on dosimetric properties of this T.L. phosphor was also investigated. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom using facilities both in these laboratories and also in radiology departments of various district hospitals in Hong Kong. Radiation absorbed dose from the direct or scattered beam, at critical sites inside and on the surface of the phantom, were measured in these radiological studies. The special focus in some of these studies was to

  13. Thermoluminescent dosemeters (TLD) exposed to high fluxes of gamma radiation, thermal neutrons and protons

    International Nuclear Information System (INIS)

    Gambarini, G.; Martini, M.; Meinardi, F.; Raffaglio, C.; Salvadori, P.; Scacco, A.; Sichirollo, A.E.

    1996-01-01

    Thermoluminescent dosemeters (TLD), widely experimented and utilized in personal dosimetry, have some advantageous characteristics which induce one to employ them also in radiotherapy. The new radiotherapy techniques are aimed at selectively depositing a high dose in cancerous tissues. This goal is reached by utilising both conventional and other more recently proposed radiation, such as thermal neutrons and heavy charged particles. In these inhomogeneous radiation fields a reliable mapping of the spatial distribution of absorbed dose is desirable, and the utilized dosemeters have to give such a possibility without notably perturbing the radiation field with the materials of the dosemeters themselves. TLDs, for their small dimension and their tissue equivalence for most radiation, give good support in the mapping of radiation fields. After exposure to the high fluxes of therapeutic beams, some commercial TL dosemeters have shown a loss of reliability. An investigation has therefore be performed, both on commercial and on laboratory made phosphors, in order to investigate their behaviour in such radiation fields. In particular the thermal neutron and gamma ray mixed field of the thermal column of a nuclear reactor, of interest for Boron Neutron Capture Therapy (B.N.C.T.) and a proton beam, of interest for proton therapy, were considered. Here some results obtained with new TL phosphors exposed in such radiation fields are presented, after a short description of some radiation damage effect on commercial LiF TLDs exposed in the (n th ,γ) field of the thermal column of a reactor. (author)

  14. Commissioning (Method Development) of the Panasonic UD-794 Automatic Thermoluminescent Dosemeter (TLD) Irradiator

    International Nuclear Information System (INIS)

    McKittrick Leo

    2005-08-01

    This study is presented in two parts. Part 1, the Literature Survey examines the history, theory and application of TL dosimetry. A general overview of the thermoluminescent dosemeter is presented together with a complete in-depth look at the Panasonic UD-716 TLD Reader. The irradiation and calibration of TL Dosemeters is also examined together with an overview of past papers and research carried out on related topics. Part 2 documents the study of commissioning the Panasonic UD-794 Automatic TLD Irradiator, the section includes; methods and procedures used with several dosimetry instruments and materials; method development with the irradiator; results and findings from the irradiator compared to a certified method of irradiation, using the methods developed; investigations of irradiator parameters-features; conclusions made from carrying out the study of commissioning the Panasonic UD-794 Automatic TLD Irradiator

  15. Characterization of a two-component thermoluminescent albedo dosemeter according to ISO 21909

    Energy Technology Data Exchange (ETDEWEB)

    Martins, M.M., E-mail: marcelo@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Mauricio, C.L.P., E-mail: claudia@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Pereira, W.W., E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Silva, A.X. da, E-mail: ademir@con.ufrj.b [Coordenacao dos Programas de Pos-Graduacao em Engenharia, COPPE/PEN Caixa Postal 68509, CEP 21941-972, Rio de Janeiro, RJ (Brazil)

    2011-05-15

    A two-component thermoluminescent albedo neutron monitoring system was developed at Instituto de Radioprotecao e Dosimetria, Brazil. As there is no Brazilian regulation for neutron individual monitoring service, the system was tested according to the ISO 21909 standard. This standard provides performance and test requirements for determining the acceptability of personal neutron dosemeters to be used for the measurement of personal dose equivalent, H{sub p}(10), in neutron fields with energies ranging from thermal to 20 MeV. Up to 40 dosemeters were used in order to accomplish satisfactorily the requirements of some tests. Despite operational difficulties, this albedo system passed all ISO 21909 performance requirements. The results and problems throughout this characterization are discussed in this paper.

  16. Study of the influence of the time temperature profile on the minimum detectable dose of TLD-100

    International Nuclear Information System (INIS)

    Meireles, Leonardo S.; Lacerda, Marco Aurelio S.; Meira-Belo, Luiz C.; Ferreira, Hudson R.

    2013-01-01

    Monitoring of workers and workplaces is an integral part of any radiation protection programme (RPP). It is essential to demonstrate compliance with regulations that limit the allowable dose to the public from manmade sources and to enable the responsible of the installations to verify compliance with the legal dose limits to the workers and ALARA goals. Thermoluminescent dosemeters (TLDs) are generally employed to assess the environmental and personnel doses. To completely characterize a TLD dosimetry system is fundamental to determine the Lowest Dose that the system is capable of measuring. As the amount of the light emitted by TLD material is a function of the time temperature profile (TTP), in the present study, the influence of the TTP on the Detection Threshold (MDD) of the LiF:Mg,Ti (TLD-100) detectors was evaluated. Eighteen different TTPs were tested for two different annealing processes: (I) utilization of the TTP itself and; (II) a microprocessor controlled oven annealing procedure. Results showed that TTP choice can influence significantly in the MDD values. The worst results were generally found for TLDs annealed by the TTP itself. The lack of pattern or the unexpected behavior to the influence of some parameters of the TTP on the calculated MDDs must be carefully investigated. Greater variations on the TTP parameters must be undertaken. Special attention must be also done on the methodology of calculating the MDDs. (author)

  17. Thermoluminescent and optical processes in alkaline halogenides dosemeters contaminated with Europium

    International Nuclear Information System (INIS)

    Barboza F, M.; Melendrez, R.; Castaneda, B.; Pedroza M, M.; Chernov, V.; Perez S, R.; Aceves, R.

    2000-01-01

    Recent research results are presented about the properties of the optical processes of photo transferred thermoluminescence (TLFT), optical whitening (BO), thermoluminescence induced by light (TLL) and its effect in the thermoluminescent curve (Tl) produced by ionizing and non-ionizing radiation. The systematic analysis of all these processes, acquires a singular importance due that actually the alkaline halogenide crystals are object of intense investigations which analyse their potential applications as detectors and radiation dosemeters through stimulated optical luminescence techniques or thermoluminescence. The obtained data show that the Tl curve of material with this nature can be enormously affected by exposure of phosphorus to the environmental light or UV. This is in part due to liberation processes of charge bearers are shouted and makes a subsequent trapping in less temperature traps; at the same time that induce changes in the intensity of determined Tl bands. Additionally, also it is observed that mentioned phenomena are related as with wavelength of incident light as of the illumination time. Finally, the obtained information allows to conclude that although the illumination effect is extremely complex, it is associated and can be explained mainly with phenomena that implicate the electrons excitation trapped in form of F centers and trapping mechanisms or radioactive and non-radioactive recombination. (Author)

  18. Reproducibility study of TLD-100 dosimeters for {sup 122}I seeds used in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Zeituni, Carlos A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil); E-mail: czeituni@ipen.br; Moura, Eduardo S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Faculdade Oswaldo Cruz, Sao Paulo, SP (Brazil); Manzoli, Jose E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade Sao Judas Tadeu, Sao Paulo, SP (Brazil); Terremoto, Luis A.A.; Rostelato, Maria Elisa C.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2007-07-01

    In order to provide the dosimetry for {sup 125}I 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 precision of the response will not be the same. As a consequence, they must be measured one by one. This paper presents the calculation methodology for selection procedure to TLD-100 dosimeter used, embracing 143 TLD-100 dosimeters prepared by Harshaw Company on December 19th, 2005. These dosimeters are LiF type with a micro-cube (1 mm x 1 mm x 1 mm) shape. The annealing procedure used for these dosimeters consists of annealing the TLD dosimeters at 400 deg C for 65 minutes using a PC controlled annealing oven. This procedure is followed by an oven-typical cooling down profile to about 100 deg C for 127 minutes. The pre-readout thermal stabilization was used and it consists of an annealing at 100 deg C for 15 minutes. Irradiations were performed using 36 {sup 125}I seeds with activity of 0,623 mCi (23,05 MBq) on October 20th, 2006 for approximately 150 minutes, to guarantee a minimum of 5 Gy absorbed dose in each dosimeter. Different evanescence times have been used. These complete procedures were carried out four times in order to compare the data and minimize the systematic error. (author)

  19. Reproducibility study of TLD-100 dosimeters for 122I seeds used in brachytherapy

    International Nuclear Information System (INIS)

    Zeituni, Carlos A.; Moura, Eduardo S.; Manzoli, Jose E.; Terremoto, Luis A.A.; Rostelato, Maria Elisa C.M.

    2007-01-01

    In order to provide the dosimetry for 125 I 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 precision of the response will not be the same. As a consequence, they must be measured one by one. This paper presents the calculation methodology for selection procedure to TLD-100 dosimeter used, embracing 143 TLD-100 dosimeters prepared by Harshaw Company on December 19th, 2005. These dosimeters are LiF type with a micro-cube (1 mm x 1 mm x 1 mm) shape. The annealing procedure used for these dosimeters consists of annealing the TLD dosimeters at 400 deg C for 65 minutes using a PC controlled annealing oven. This procedure is followed by an oven-typical cooling down profile to about 100 deg C for 127 minutes. The pre-readout thermal stabilization was used and it consists of an annealing at 100 deg C for 15 minutes. Irradiations were performed using 36 125 I seeds with activity of 0,623 mCi (23,05 MBq) on October 20th, 2006 for approximately 150 minutes, to guarantee a minimum of 5 Gy absorbed dose in each dosimeter. Different evanescence times have been used. These complete procedures were carried out four times in order to compare the data and minimize the systematic error. (author)

  20. Exposure levels to radiation in a nuclear medicine laboratory: measurements with thermoluminescence dosemeters

    International Nuclear Information System (INIS)

    Ruiz J, A.

    2000-01-01

    Since 1996 in the Nuclear medicine Department and another routine and research departments of the National Institute of Medical and Nutrition Sciences (INCMNSZ) are working at least with 12 radioactive sources opened and sealed. However, it was unknown if with the Tl personal dosemeters with lithium fluoride crystals (LiF), could be possible to receive information about the equivalent dose for each radionuclide or if there was some radionuclide that by being low energy emissor or beta energy emissor, it did not represent an ionization power sufficient to excite the crystals of the thermoluminescent dosemeters (DTL). In this work the obtained results with control dosemeters of diverse source opened or sealed are shown, which were put at 1 cm of the LiF crystals during a time exposure 18 hours. Therefore the objective of this work is to verify which sources excite or not to DTL crystals and taking the pertinent safety measures for each radionuclide. The conclusion is that the majority of dosemeters were excited by beta or gamma radiation of the radionuclides and that LiF crystals are able to receive equivalent doses until 1200 mSv, being this a guarantee for the staff, that in an any moment could be exposed to high dose in his working day. Also it was corroborated that the radionuclides more energizer are: iodine-131, iodine-125 and sodium-22 while the phosphorus-32 must be managed with careful, since the exposure to hands can result significant, just like the technetium-99m ( 99m Tc). (Author)

  1. The fast neutron response of 7LiF thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Knipe, A.D.

    1990-02-01

    A series of experiments was performed in 1982 to determine the neutron energy response of the 7 LiF thermoluminescent dosemeter (TLD) employed in European zero power fast reactor gamma-ray energy deposition studies. Preliminary results of this work were included in a 1985 International experimental data-base of TLD neutron sensitivities and provided the most consistent set of data within the 7 LiF compilation. A more detailed interpretation of these data has improved the results still further, giving a mean relative neutron to gamma efficiency of 0.118±0.005. The main objective of this re-evaluation was to establish recommended neutron energy response values to replace a 1974 data set for the analysis of in-core fast reactor measurements. This was achieved by combining the mean experimental relative efficiency of 0.118 with calculated energy dependent kerma factors. The kerma factors for the TLD were based on US National Bureau of Standards values and a composition determined by chemical analysis. Adoption of the revised neutron energy response data set produces a small increase in the measured gamma-ray energy deposition of typically 2% relative to the 1974 data. However, more importantly, the detailed analysis of the experimental response data has significantly improved confidence in the neutron corrections applied to in-core TLD gamma-ray energy deposition measurements. (author)

  2. Environmental gamma-ray dose measurements with thermoluminescence dosemeters (TLD) and environmental radiation characteristics

    International Nuclear Information System (INIS)

    Kanematsu, Seiko

    1999-01-01

    It is important to evaluate environmental gamma-ray exposure both at work and home in order to assess people's collective dosages. Environmental gamma radiation was measured for air-absorbed dose with a thermoluminescence dosemeter at various points in the workplace and Ningyotoge, and workplace radiation characteristics were analyzed. From the results, the public dose due to gamma rays generated artificially was assessed to be sufficiently lower than the annual limit. For indoor environments of the workplace, the maximum dosage rate among measured values was 97 nGy/h and the minimum value was 70 nGy/h, the average over one year was 83 nGy/h. The average annual outdoor dosage for a year was 82 nGy/ h. In Ningyotoge, the maximum was 103 nGy/h, minimum 60 nGy/h, and average 88 nGy/h. These values depend on the nature of the soil and weather factors, showing higher values in the summer than in the winter in the workplace. There was no significant difference in the dosage rate in houses and the workplace. (author)

  3. Evaluation of LiF:Mg,Ti (TLD-100 for Intraoperative Electron Radiation Therapy Quality Assurance.

    Directory of Open Access Journals (Sweden)

    Raffaele Liuzzi

    Full Text Available Purpose of the present work was to investigate thermoluminescent dosimeters (TLDs response to intraoperative electron radiation therapy (IOERT beams. In an IOERT treatment, a large single radiation dose is delivered with a high dose-per-pulse electron beam (2-12 cGy/pulse during surgery. To verify and to record the delivered dose, in vivo dosimetry is a mandatory procedure for quality assurance. The TLDs feature many advantages such as a small detector size and close tissue equivalence that make them attractive for IOERT as in vivo dosimeters.LiF:Mg,Ti dosimeters (TLD-100 were irradiated with different IOERT electron beam energies (5, 7 and 9 MeV and with a 6 MV conventional photon beam. For each energy, the TLDs were irradiated in the dose range of 0-10 Gy in step of 2 Gy. Regression analysis was performed to establish the response variation of thermoluminescent signals with dose and energy.The TLD-100 dose-response curves were obtained. In the dose range of 0-10 Gy, the calibration curve was confirmed to be linear for the conventional photon beam. In the same dose region, the quadratic model performs better than the linear model when high dose-per-pulse electron beams were used (F test; p<0.05.This study demonstrates that the TLD dose response, for doses ≤10 Gy, has a parabolic behavior in high dose-per-pulse electron beams. TLD-100 can be useful detectors for IOERT patient dosimetry if a proper calibration is provided.

  4. 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.

  5. Fractional order of kinetics in LiF-TLD 100

    International Nuclear Information System (INIS)

    Moharil, S.V.

    1984-01-01

    In a recent letter, it has been argued that the non-first-order kinetics for LiF-TLD 100 obtained by Kathuria and Sunta (J. Phys. D: Appl. Phys. 12, 1573) is an artefact of their experimental set-up. In this letter it is shown that this is not the case. (author)

  6. 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)

  7. Environmental dosimetry system based on LiF : Mg, Ti (TLD-100)

    International Nuclear Information System (INIS)

    Saez Vergara, J.C.

    1990-01-01

    The report presents the various tests carried out to the characterize a thermoluminescence environmental dosimetry systems, using the phosphor LiF:mg,Ti (TLD-100) in chip form. The holder has been specifically designed in order to obtain simplicity in the operation and to assure correct measurements in terms of the new operational quantities in radiation protection (ICRU-1985). Some topics in TLD Environmental Monitoring are discussed (Dark Current, Reference Light, Zero Reading, Free-in-Air or Phantom Calibration, Fading Correction, Transit Dose, etc.), and the proposed solutions are exposed. The tests performed have been designed to conform with the different existing international Standards and Recommendations (ANSI : N545-1975; IEC: Draft 45B-1987, ISO : DP 8034-19849. The data from an European Interlaboratory Programm (EUR-8932) have been used to evaluate the performance : the TLD System presented is among the best systems using TLD-100. The results obtained in the characterization (linearity, repeatability, detection threshold, residue, angular response, stability of stored information, etc.) show the optimum performance of this dosimetric system in its application to environmental gamma dose monitoring. Based on these results, two operational procedures have been developed for the application of this Dosimetric System, specially in Quality Assurance Monitoring Programs around Nuclear Plants in Spain. (author)

  8. Dose profile measurement in computerized axial tomography equipment using thermoluminescent dosemeters; Medicion del perfil de dosis en equipos de tomografia axial computarizada usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, J.C.; Falcony, C.; Azorin N, J. [Centro de Investigacion en Ciencia y Tecnologia Avanzada, IPN, 07000 Mexico D.F. (Mexico)

    2000-07-01

    In this work are presented the results about measuring the radiation dose profile in two equipment of computerized axial tomography (Tac). Thermoluminescent dosemeters (Dtl) of LiF, Mg, Cu, P + Ptfe in form of disks were used which were developed and made in Mexico. The results showed that Dtl are appropriated for these type of studies. (Author)

  9. Characterization of TLD-100 micro-cubes for use in small field dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Peña-Jiménez, Salvador, E-mail: zoid-9861@yahoo.com.mx; Gamboa-deBuen, Isabel, E-mail: gamboa@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 DF (Mexico); Lárraga-Gutiérrez, José Manuel, E-mail: jose.larraga.gtz@gmail.com, E-mail: amanda.garcia.g@gmail.com; García-Garduño, Olivia Amanda, E-mail: jose.larraga.gtz@gmail.com, E-mail: amanda.garcia.g@gmail.com [Laboratorio de Física Médica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Av. Insurgentes Sur 3877, 14269 DF (Mexico)

    2014-11-07

    At present there are no international regulations for the management of millimeter scale fields and there are no suggestions for a reference detector to perform the characterization and dose determination for unconventional radiation beams (small fields) so that the dosimetry of small fields remains an open research field worldwide because these fields are used in radiotherapy treatments. Sensitivity factors and reproducibility of TLD-100 micro-cubes (1×1×1 mm3) were determinate irradiating the dosimeters with a 6 MV beam in a linear accelerator dedicated to radiosurgery at the Instituto Nacional de Neurología y Neurocirugía (INNN). Thermoluminescent response as a function of dose was determined for doses in water between 0.5 and 3 Gy and two field sizes (2×2 cm2 and 10×10 cm2). It was found that the response is linear over the dose range studied and it does not depend on field size.

  10. Response of TLD-100 LiF dosimeters for X-rays of low energies

    International Nuclear Information System (INIS)

    Bonzi, E. V.; Mainardi, R. T.

    2011-10-01

    In diverse practical applications as the existent in radiological clinics, industrial facilities and research laboratories, the solid state dosimeters are used for the measure of the different types of ionizing radiations. At the present time dosimeters are manufactured with different types of materials that present thermoluminescent properties, to the effects of determining the absorbed radiation dose. Under these conditions, the radiation dose is determined integrated in all the range of energies of the beam of X-rays, since it assumes that the response of these dosimeters is lineal with the energy of the photons or radiant particles. Because interest exists in advancing in the development of a determination method in the way of the X-rays spectrum emitted by a tube of those used in diagnostic or therapy, we have measured the response of TLD-100 LiF dosimeters for low energies, minor at 60 keV, for a several group of these dosimeters. (Author)

  11. Mine test of thermoluminescence energy discriminatory track etch personal dosemeters in uranium mines having nearly equal concentrations of radon and thoron daughters

    International Nuclear Information System (INIS)

    Pai, H.L.; Jokura, K.; Phillips, C.R.

    1981-01-01

    Energy discriminatory CEA track etch dosemeters and LiF thermoluminescence dosemeters were used to record the total dose in a uranium mine atmosphere containing both radon daughters and thoron daughters in approximately equal concentrations. In addition, the track etch dosemeters were used to record the individual concentrations of RaA, RaC' and ThC', thereby allowing calculation of the separate radon daughter and thoron daughter working levels. The pump performance of the dosemeters was characterized in terms of durability, stability and sensitivity to attitude, vibration and impact. Grab sampling results taken in the work area were not representative of all of the individual miner exposures because of the strong effect of job function on exposure. (author)

  12. Indoor gamma radiation monitoring In Rawalpindi, Pakistan using TLD100

    International Nuclear Information System (INIS)

    Azam, Sana; Tufail, Muhammad; Sohail, Muhammad

    2008-01-01

    Full text: Natural radioactivity originates from extraterrestrial sources as well as from radioactive elements in earth's crust. The amount of radioactivity varies from place to place and with altitude. The aim of this study was to observe the indoor radiation level in Rawalpindi using TLD. For this purpose LiF:Mg:Ti (TLD100) chips were used. Chips were annealed and then calibrated using different sources and the calibration factor obtained by using Cs137 source was selected for dose estimation. Its value was 0.1403 μGy/TL response. Rawalpindi categorized into six regions. In each region, 5 cemented houses were selected and TLD 100 chips were placed at a distance of 0.5 m from ground the level. Chips were properly covered to protect them from ultraviolet light and moisture and were placed for three months. The average annual indoor dose rate for Rawalpindi was estimated to be 392.105μGy/yr and average dose to be 97.65μGy. Therefore, the effective dose for population of Rawalpindi from indoor gamma radiation was estimated to be 313.68μSv/yr using an indoor occupancy factor of 80%. (author)

  13. Use of TLD-100 to verify a dosimetric method for total electron skin irradiation

    International Nuclear Information System (INIS)

    Mesa, F.; Sosa, M.

    2007-01-01

    Full text: A clinical dosimetric method for generating a homogeneous field of radiation around of patients under treatment of total skin electron irradiation and its verification using thermoluminescent dosimetry is presented. The irradiations were performed utilizing a 6 MeV electron beam generated by a Varian Clinac 21EX linear accelerator installed in the oncology unit of the IMSS-Tl hospital in Leon. Levels of radiation for diverse adjustment performed in the treatment planning system of the lineal accelerator and registered to different treatment distances using a computerized water phantom system were studied. A large batch of TLD-100 chips calibrated in terms of air-kerma rate to the standard treatment distance and positioned in an anthropomorphic Alderson Random Phantom was used. Dose verification and comparison with the measurements made with the computerized system were analyzed. A single field electron beam for treatment of total skin irradiation was implemented. Preliminary results indicate that the levels of dose homogeneities were larger than 90% for distances up to 3.0 m. The results suggest that the method developed is a reliable for delivering an electron beam with significantly homogeneity for these treatments. Analyses and results of both thermoluminescent and computerized dosimetric system calibrations are also presented. (Author)

  14. 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

  15. 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.)

  16. Calibration procedure for thermoluminescent dosemeters in water absorbed doses for Iridium-192 high dose rate sources

    International Nuclear Information System (INIS)

    Reyes Cac, Franky Eduardo

    2004-10-01

    Thermoluminescent dosimeters are used in brachytherapy services quality assurance programs, with the aim of guaranteeing the correct radiation dose supplied to cancer patients, as well as with the purpose of evaluating new clinical procedures. This work describes a methodology for thermoluminescent dosimeters calibration in terms of absorbed dose to water for 192 Ir high dose rate sources. The reference dose used is measured with an ionization chamber previously calibrated for 192 Ir energy quality, applying the methodology proposed by Toelli. This methodology aims to standardizing the procedure, in a similar form to that used for external radiotherapy. The work evolves the adaptation of the TRS-277 Code of the International Atomic Energy Agency, for small and big cavities, through the introduction for non-uniform experimental factor, for the absorbed dose in the neighborhood of small brachytherapy sources. In order to simulate a water medium around the source during the experimental work, an acrylic phantom was used. It guarantees the reproducibility of the ionization chamber and the thermoluminescent dosimeter's location in relation to the radiation source. The values obtained with the ionization chamber and the thermoluminescent dosimeters, exposed to a 192 Ir high dose rate source, were compared and correction factors for different source-detector distances were determined for the thermoluminescent dosimeters. A numeric function was generated relating the correction factors and the source-detector distance. These correction factors are in fact the thermoluminescent dosimeter calibration factors for the 192 Ir source considered. As a possible application of this calibration methodology for thermoluminescent dosimeters, a practical range of source-detector distances is proposed for quality control of 192 Ir high dose rate sources. (author)

  17. Determination of the dose index in computerized tomography using thermoluminescent dosemeters; Determinacion del indice de dosis en tomografia computada usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Azorin, J.C.; Calderon, A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-IPN, 11500 Mexico D.F. (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico)

    2004-07-01

    In this work the obtained results of the determination of the dose index are presented in thorax studies in computed tomography and helical tomography carried out in Mexico using thermoluminescent dosemeters of LiF: Mg,Cu,P + Ptfe developed and manufactured in our country. The results showed that under similar conditions of irradiation and operation (pitch = 1), significant differences don't exist among the doses absorbed measures in the phantom due to the two types of used tomographs. (Author)

  18. Production dosimeter LiF: Mg, Ti and comparison its responses with dosimeter LiF: Mg, Ti (TLD-100) in Harshaw company against of gamma rays

    OpenAIRE

    KH Mohammadi; R Sarraf Maamory; R Mohammadi; A Mosavi Zarandi

    2010-01-01

    Thermoluminescence dosimeters are small tablets used with 3. 2*3. 2*0. 9mm^3 for measurement of received dose from radioactive various beams. The most common dosimeter is TLD-100 which is lithium-fluoride family and this dosimeter contain magnesium impurities. In this study, first lithium-flouride powder was mixed with titanium and controlled atmosphere samples were heated. After measuring of samples density and hardness, their glow curves were drawn and microscopic pictures of producted samp...

  19. Utilization of thermoluminescent dosemeters in radiation field studies for different materials

    International Nuclear Information System (INIS)

    Carron, W.; Guilardi Neto, T.

    1987-01-01

    The dose conversion factor of lithium fluoride thermoluminescent for the follows materials: water, wood and soil, the dose curve surveying in function of depth and the regression equations that better adapt to the dose curves were calculated. (C.G.C.) [pt

  20. Solid thermoluminescent dosemeter of sodium tetraborate and brazilian fluoride sensitive to thermal neutrons

    International Nuclear Information System (INIS)

    Fratin, L.

    1988-01-01

    The techniques of compacting sodium tetraborate and natural fluoride mixtures were studied in this work, with the aim of producing a solid dosimeter sensitive to thermal neutrons. The production procedure involves the vitrification of the sodium tetraborate, the grinding, mixture, cold pressing and the sinterization of the pellets. A special arrangement was built for irradiation where paraffin was used as moderator for neutrons from a 241 Am-Be source. Two different mass ratios of sodium tetraborate and flourite showed a linear thermoluminescent response to the neutron fluence in the range of 1.0 to 7.0 x 10 8 n (sub)tcm -2 . Solid dosimeters, manufactured from natural fluorite and sodium chloride, showed a response to gamma radiation similar to the response of the dosimeters sensitive to neutrons. These dosimeters are need to identify the proportion of thermoluminescent response due to gamma radiation present in a neutron field. (author) [pt

  1. Measurement of doses to aviator pilots using thermoluminescent dosemeters; Medicion de la dosis a pilotos aviadores usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Azorin N, J.; Cruz C, D. [UAM-I, 09340 Mexico D.F. (Mexico); Rivera M, T. [IPN, ESIME Culhuacan (Mexico)]. e-mail: azorin@xanum.uam.mx

    2004-07-01

    During the development of their work, the aviator pilots are exposed at high levels of natural radiation of bottom caused mainly by the cosmic radiation of galactic origin and lot. For such reason, the Metropolitan Autonomous University (UAM) and the Union Association of Aviator Pilots (ASPA), subscribed an agreement with the purpose of to measure the doses of ionizing radiation received by the aviator pilots of diverse air companies that man different types of airships and to determine if these doses surpass the one limit of 0.11 mSv/h settled down by the IAEA for the public in general; and if therefore, these workers should be considered as personnel occupationally exposed. In this work the obtained results when measuring the absorbed dose received by Mexican civil aviator pilots during the development of their work, using thermoluminescent dosemeters of LiF:Mg,Cu,P + Ptfe of national production are presented. The obtained results during the years of 2001 and 2002 show that the monthly doses received by the pilots surpass the one it limits established for the public in general, for what they should be considered as personnel occupationally exposed. (Author)

  2. Contribution to the optimization of individual dose measurement with TLD 100 using the TLD reader 6600

    International Nuclear Information System (INIS)

    RAFARAVAVY, R.

    2003-01-01

    In Madagascar, thermoluminescent dosimeters are used for individual monitoring of personal exposed by ionising radiation. This work consist to find the optimal condition of reading parameters, to calibrate the reader HARSHAW TLD 6600, and to determine the lower value of dose measurable by the TLD 100. The betters values of the temperature rate, the preheat time and the anneal time are respectively 21 0 C s - 1, 9s and 5s. Calibration of the reader HARSHAW TLD 6600 has permitted to have true value conventional. The calibration factors corresponding to the pastille of dosimeter which measure the whole body dose and the one which measure the skin dose are respectively 0.031nC μSv - 1 and 0.035 nCμSv-1. These calibration factors are tied to measured parameters values mentioned above. The lower limit of detection found is equal to 10.12 μSv. All measured values (background deduced) less than this lower limit of detection are considered as background fluctuation [fr

  3. About the measurements systems with pen and thermoluminescent dosemeters; Sobre los sistemas de medicion con dosimetros de pluma y los termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Cortes I, M.E.; Ramirez G, F.P. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152. 07730 Mexico D.F. (Mexico)

    1998-12-31

    In this work it is presented dosimetric data obtained with pen and thermoluminescent dosemeters, which are used by the Occupational Exposure Personnel (OEP) of the Mexican Petroleum Institute (IMP)(1). It was marked several great characteristics as for example, the differences among units which use one and another dosemeter type. Likewise, it is given to know diverse problems that were had in the IMP at relating the data obtained with these dosemeters (which utilizes OEP) and the ICRP 60 recommendations 1990. One of the most important difficulties is to satisfy the recommended limits by ICRP, particularly those that are referring to the units and their complex calculations. With respect to the unities, the ICRP makes reference at the concepts `dose equivalent` and `effective dose` with the sievert unit, that the General Regulations for Radiological Safety associates with `dose equivalent` and `effective dose equivalent`. It was illustrated the type of dosimetric statistics which are obtained with the TLD lectures and a OEP pen dosemeter during 1997. (Author)

  4. Response of TLD-100 LiF dosimeters for X-rays of low energies; Respuesta de dosimetros de TLD-100 de LiF para rayos X de bajas energias

    Energy Technology Data Exchange (ETDEWEB)

    Bonzi, E. V.; Mainardi, R. T. [Universidad Nacional de Cordoba, Facultad de Matematica, Astronomia y Fisica, Av. Haya de la Torre y Av. Medina Allende s/n, Ciudad Universitaria, X5016LEA Cordoba (Argentina)

    2011-10-15

    In diverse practical applications as the existent in radiological clinics, industrial facilities and research laboratories, the solid state dosimeters are used for the measure of the different types of ionizing radiations. At the present time dosimeters are manufactured with different types of materials that present thermoluminescent properties, to the effects of determining the absorbed radiation dose. Under these conditions, the radiation dose is determined integrated in all the range of energies of the beam of X-rays, since it assumes that the response of these dosimeters is lineal with the energy of the photons or radiant particles. Because interest exists in advancing in the development of a determination method in the way of the X-rays spectrum emitted by a tube of those used in diagnostic or therapy, we have measured the response of TLD-100 LiF dosimeters for low energies, minor at 60 keV, for a several group of these dosimeters. (Author)

  5. 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)

  6. Analysis of read-out heating rate effects on the glow peaks of TLD-100 using WinGCF software

    Energy Technology Data Exchange (ETDEWEB)

    Bauk, Sabar, E-mail: sabar@usm.my [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Hussin, Siti Fatimah [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Alam, Md. Shah [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Physics Department, Shahjalal University of Science and Technology, Sylhet (Bangladesh)

    2016-01-22

    This study was done to analyze the effects of the read-out heating rate on the LiF:Mg,Ti (TLD-100) thermoluminescent dosimeters (TLD) glow peaks using WinGCF computer software. The TLDs were exposed to X-ray photons with a potential difference of 72 kVp and 200 mAs in air and were read-out using a Harshaw 3500 TLD reader. The TLDs were read-out using four read-out heating rates at 10, 7, 4 and 1 °C s{sup −1}. It was observed that lowering the heating rate could separate more glow peaks. The activation energy for peak 5 was found to be lower than that for peak 4. The peak maximum temperature and the integral value of the main peak decreased as the heating rate decreases.

  7. Determination of the dose rapidity of a {sup 90} Sr beta radiation source using thermoluminescent dosemeters; Determinacion de la rapidez de dosis de una fuente de radiacion beta de {sup 90}Sr usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P.R.; Azorin N, J.; Rivera M, T. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    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 {sup 90} Sr-{sup 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)

  8. A glow curve analyzer (GCA) for routine analysis of personnel thermoluminescent dosemeter results

    International Nuclear Information System (INIS)

    Chase, W.J.; Bezaire, M.D.; Vanderzwet, F.P.; Taylor, C.E.

    2008-01-01

    A glow curve analyzer (GCA) spreadsheet has been developed using Microsoft Excel to perform glow curve analysis on thermoluminescent dosimeter (TLD) data from a personnel dosimetry system. The TLD data come from cards with four LiF:Mg,Ti chips that have been annealed and therefore have a simple glow peak structure. GCA removes spikes in the glow curve data, and then smoothes it. After select start and end points for the glow peak, it fits a Boltzmann function to represent the glow curve signal background under the glow peak. The Boltzmann function is subtracted and two Weibull curves are fit to the remaining net signal between the start and end points. The first Weibull curve is fit to peak 5, and the second one to any small remaining contribution from peaks 3 and 4 or from contaminants. The sum of the two Weibull curves is the glow curve signal result. GCA provides rapid review and correction of all glow curves, improving the quality of the results and reducing the time required for complete processing of official dose results

  9. Thermoluminescent and optical processes in alkaline halogenides dosemeters contaminated with Europium; Procesos opticos y termoluminiscentes en dosimetros de halogenuros alcalinos contaminados con Europio

    Energy Technology Data Exchange (ETDEWEB)

    Barboza F, M.; Melendrez, R.; Castaneda, B.; Pedroza M, M.; Chernov, V.; Perez S, R.; Aceves, R. [Centro de Investigacion en Fisica, Universidad de Sonora, A.P. 5-088, 83190 Hermosillo, Sonora (Mexico)

    2000-07-01

    Recent research results are presented about the properties of the optical processes of photo transferred thermoluminescence (TLFT), optical whitening (BO), thermoluminescence induced by light (TLL) and its effect in the thermoluminescent curve (Tl) produced by ionizing and non-ionizing radiation. The systematic analysis of all these processes, acquires a singular importance due that actually the alkaline halogenide crystals are object of intense investigations which analyse their potential applications as detectors and radiation dosemeters through stimulated optical luminescence techniques or thermoluminescence. The obtained data show that the Tl curve of material with this nature can be enormously affected by exposure of phosphorus to the environmental light or UV. This is in part due to liberation processes of charge bearers are shouted and makes a subsequent trapping in less temperature traps; at the same time that induce changes in the intensity of determined Tl bands. Additionally, also it is observed that mentioned phenomena are related as with wavelength of incident light as of the illumination time. Finally, the obtained information allows to conclude that although the illumination effect is extremely complex, it is associated and can be explained mainly with phenomena that implicate the electrons excitation trapped in form of F centers and trapping mechanisms or radioactive and non-radioactive recombination. (Author)

  10. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P Thermoluminescent Dosemeter and its applications in diagnostic radiology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Fung, K.L. E-mail: orkarl@polyu.edu.hk

    2004-05-01

    This study investigated the dosimetric properties of the high sensitivity TLD (Thermoluminescent Dosemeter) of LiF:Mg,Cu,P and its applications in diagnostic radiology. A reproducible readout and annealing regime for this high sensitivity TLD was developed in the initial part of this study with the newly installed automatic TLD Reader system. Basic dosimetric characteristics of this T.L. dosemeter were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom. The applications studied in radiological procedures included: dose reduction in lumbar spine radiography utilizing the 'anode heel effect'; gonad dose variation with kV{sub p} in chest radiography; foetal dose comparison between computed tomography (CT) and computed radiography (CR) in X-ray pelvimetry; lens dose reduction with bismuth eye-shields in CT brain studies; foetal dose assessment of early pregnancy in common high risk radiological examinations. It is anticipated that the unique and favourable dosimetric performance of LiF:Mg,Cu,P T.L. phosphor will be exploited further in measurements of low level dose received by patients and staff in diagnostic radiological procedures such as paediatric X-ray examinations.

  11. Measure of the attenuation curve of a beam of X-rays with TLD-100 dosimeters of LiF; Medicion de la curva de atenuacion de un haz de rayos X con dosimetros TLD-100 de LiF

    Energy Technology Data Exchange (ETDEWEB)

    Bonzi, E. V.; Mainardi, R. T. [Universidad Nacional de Cordoba, Facultad de Matematica, Astronomia y Fisica, Av. Haya de la Torre y Av. Medina Allende s/n, Ciudad Universitaria, Cordoba (Argentina); Germanier, A. [Ministerio de Ciencia y Tecnologia, Ceprocor, Unidad de Estudios Fisicos, Alvarez de Arenas 230, X5004AAP Barrio Juniors, Cordoba (Argentina); Delgado, V. [Universidad Complutense de Madrid, Departamento de Fisica Medica, Ciudad Universitaria, 28040 Madrid (Spain)

    2011-10-15

    The attenuation curve of a beam of X-rays represents the beam intensity in function of the attenuator thickness interposed between the source and the detector. To know with the major possible precision the attenuation curve is indispensable in procedures of spectral reconstruction. Their periodic measuring also offers valuable information on the correct operation of a tube of X-rays, diagnostic or therapy, when not have a specific detector for that activity. In this work was measured the attenuation curve of a tube of X-rays operated to 50 kV and 0.5 ma, using existent elements in any diagnostic or therapy laboratory with radiations. In the measures commercial aluminum foil was used, bent until 24 times and thermoluminescent dosimeters TLD 100 - LiF. Also, for comparison, was measured this attenuation curve with an ionization chamber brand Capintec model 192. Was determined by X-rays fluorescence the composition of the aluminium foil, since the present elements in the alloy can to affect the form of the attenuation curve. It is interesting to observe that these elements are in very low proportion (ppm) that they do not alter the attenuation capacity of the pure aluminium. Finally in a precision balance we weigh a big piece (30 cm x 100 cm) of aluminium foil and we obtained the thickness in g/c m2. It is possible to obtain attenuation curves of a beam of X-rays, with a high precision procedure and reproducibility. The use of TLD-100 dosimeters of LiF or similar makes that this activity was also quick and simple. (Author)

  12. Measure of the attenuation curve of a beam of X-rays with TLD-100 dosimeters of LiF

    International Nuclear Information System (INIS)

    Bonzi, E. V.; Mainardi, R. T.; Germanier, A.; Delgado, V.

    2011-10-01

    The attenuation curve of a beam of X-rays represents the beam intensity in function of the attenuator thickness interposed between the source and the detector. To know with the major possible precision the attenuation curve is indispensable in procedures of spectral reconstruction. Their periodic measuring also offers valuable information on the correct operation of a tube of X-rays, diagnostic or therapy, when not have a specific detector for that activity. In this work was measured the attenuation curve of a tube of X-rays operated to 50 kV and 0.5 ma, using existent elements in any diagnostic or therapy laboratory with radiations. In the measures commercial aluminum foil was used, bent until 24 times and thermoluminescent dosimeters TLD 100 - LiF. Also, for comparison, was measured this attenuation curve with an ionization chamber brand Capintec model 192. Was determined by X-rays fluorescence the composition of the aluminium foil, since the present elements in the alloy can to affect the form of the attenuation curve. It is interesting to observe that these elements are in very low proportion (ppm) that they do not alter the attenuation capacity of the pure aluminium. Finally in a precision balance we weigh a big piece (30 cm x 100 cm) of aluminium foil and we obtained the thickness in g/c m2. It is possible to obtain attenuation curves of a beam of X-rays, with a high precision procedure and reproducibility. The use of TLD-100 dosimeters of LiF or similar makes that this activity was also quick and simple. (Author)

  13. 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

  14. Electronic personal dosemeters

    International Nuclear Information System (INIS)

    Marshall, T.O.; Bartlett, D.T.; Burgess, P.H.; Cranston, C.S.; Higginbottom, D.J.; Sutton, K.W.

    1990-01-01

    Personal dosimetry services approved by their national authorities for category A workers, invariably use passive dosemeters incorporating photographic film or thermoluminescent detectors. However, the performance characteristics of electronic dosemeters has improved substantially over the past decade to such an extent that in the opening lecture of the Solid State Dosimetry Conference at Oxford in 1986 the development of an electronic 'smart card' based on a silicon detector was briefly discussed. This idea has been taken up and at least one development programme is in progress aimed at the production of an electronic dosemeter suitable for use as a legal device. The more important performance requirements of personal dosemeters for this purpose are discussed and the earlier electronic dosemeter designs and the latest devices under development to meet this specification are compared. (author)

  15. Verification or treatment planning system of radiotherapy using TLD-100; Verificacion de los sistemas de planificacion de tratamiento de radioterapia empleando TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Pinuela, J., E-mail: jcpinuela@hotmail.co [Hospital Central de Maracay (Venezuela, Bolivarian Republic of). Servicio de Radioterapia

    2010-07-01

    The evaluation of the treatment planning system (TPS) used in radiotherapy Precise Plan, was carried out using TLD-100 dosimeters, comparing the dose obtained with an ionization chamber. The TLD-100 were calibrated using secondary standard of SSDL, selecting dosimeters which had a standard deviation less than 1% for dosimeter calibration and less than 5% for dosimeter of field, for the tests conducted in TPS, The Alderson Phantom was used to evaluate the wedge and bolus, and Lucy 3D allowed us to evaluate correspondence of CT numbers, volume expansion, beam shaping, precise dose and beam weigh assignment. It was observed that the results of Lucy 3D were within the values expected except the volume expansion process with more than 10% difference, the evaluation of beam modulators systems with wedges and bolus as beam shaping yielded values within the expected with variations less than 5% and to assess the supply of specific doses, it was observed that the values obtained were precise and accurate since the same variation was less than 0.5% for the test. The importance of assessing the TPS lies in our country there is no procedure to verify that system and these tests provide a basis for future comparisons. (author)

  16. 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.)

  17. A comparative evaluation of luminescence detectors: RPL-GD-301, TLD-100 and OSL-AL2O3:C, using Monte Carlo simulations

    Science.gov (United States)

    Benali, A.-H.; Medkour Ishak-Boushaki, G.; Nourreddine, A.-M.; Allab, M.; Papadimitroulas, P.

    2017-07-01

    The luminescent dosimeters are widely used in clinical practice, for the monitoring of patient dose in external radiation therapy. Three of the most common dosimeter categories are the thermoluminescence (TLDs), the radiophotoluminescence (RPLs) and the optically stimulated luminescence (OSLs), with similar physical processes on their properties. The aim of the present study is to compare and evaluate the dosimetric properties of three specific luminescent detectors namely: a) RPL glass dosimeter, commercially known as GD-301, b) lithium fluoride TLD-100 (LiF:Mg,Ti) and c) carbon-doped aluminum oxide (Al2O3:C). For this purpose, Monte Carlo simulations were applied, using the MCNP5 code to estimate the responses of these dosimeters in terms of absorbed dose, output factor, the angular and energy dependence. In the present study, we found that the differences between the output factors were less than ± 4.2% for all detector materials RPLGD, TLD and OSLD. The variations in sensitivity for angles up to ± 80 degrees from the central axis of the beam were approximately 0.5%, 0.8% and 1.5% for the TLD-100, GD-301 and Al2O3:C, respectively. The energy dependence of the RPL and OSL dosimeters are stated as less than a 2.2%, and within 5.8% for TLD.

  18. Production dosimeter LiF: Mg, Ti and comparison its responses with dosimeter LiF: Mg, Ti (TLD-100 in Harshaw company against of gamma rays

    Directory of Open Access Journals (Sweden)

    KH Mohammadi

    2010-03-01

    Full Text Available Thermoluminescence dosimeters are small tablets used with 3. 2*3. 2*0. 9mm^3 for measurement of received dose from radioactive various beams. The most common dosimeter is TLD-100 which is lithium-fluoride family and this dosimeter contain magnesium impurities. In this study, first lithium-flouride powder was mixed with titanium and controlled atmosphere samples were heated. After measuring of samples density and hardness, their glow curves were drawn and microscopic pictures of producted samples were provided. Of course, the reader should know that the best press pressure, the best range of temperature heating and the best range of samples heating were determined in 6-8 (ton/cm2, 775-800 ° C and 15-20 h, respectively [1]. Then, the response of producted TLD-100 under radiation of gamma sources, 60Co, was measured in 500 mSv rate and obtained values were compared with obtained values by Harshaw producted samples. Dosimetry characteristics of producted samples was evaluated according to ASTM E 668-00, IEC-ISO 1066 standards. The results of comparisions indicate good agreements between producted sample and Harshaw sample.

  19. 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)

  20. 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)

  1. Experimental determination of relative light conversion factors of TLD-100 for protons with energies from 2.0 to 9.0 MeV

    International Nuclear Information System (INIS)

    Schmidt, P.; Fellinger, J.; Huebner, K.; Henniger, J.

    1985-01-01

    Relative light conversion factors (RLCF) for heavy charged particles (protons, deuterons, recoils) are needed for the calculation of the neutron sensitivity of thermoluminescent (TL) detectors. Such light conversion factors can be determined experimentally. A method is represented for the experimental determination of RLCF. The described experimental facility gives the possibility of irradiation of different luminophor samples with heavy charged particles and flux determination and particle spectrometry at the same time. For the determination of RLCF the doses are needed which are applicated at the irradiation with heavy charged particles and gamma radiation, respectively, and the according detector readings at the TL evaluation. The problems arising at the dose determination are discussed. With this experimental facility the RLCF for TLD-100 for protons were determined. The relative light conversion factors determined according to the light sum method as well as the peak height method are summarizinhly represented and discussed. Furthermore a comparison of the glow curves is made after gamma and proton irradiation

  2. Experimental determination of relative light conversion factors of TLD-100 for protons with energies from 2.0 to 9.0 MeV

    International Nuclear Information System (INIS)

    Schmidt, P.; Fellinger, J.; Henniger, J.; Huebner, K.

    1988-01-01

    The efficiency of thermoluminescent (TL) detectors to heavy charged particles is described by the so-called light conversion factor η. Relative light conversion factors for protons, alphas and heavier recoils are needed for the calculation of the neutron sensitivity of TL detectors. Such light conversion factors can be determined experimentally. In this paper a method is presented for the experimental determination of relative light conversion factors. Using the experimental arrangement described, relative light conversion factors for LiF material (TLD-100) for protons were determined. In LiF the relative main peak (peak V) efficiency is always lower than 1. It increases with increasing proton energy whereas the relative efficiency of the high temperature peak (peak VI) shows an opposite dependence on the proton energy. Relative light conversion factors for peak VI clearly exceed 1. (orig.)

  3. A Dosimetry of 106-Ru - 106- Rh Electron-Photon Field with LiF TLD-100 'Microcubes'

    International Nuclear Information System (INIS)

    Kovacevic, N.; Vrtar, M.; Vekic, B.; Knezevic, Z.

    2003-01-01

    Background and purpose: Ru-Rh eye applicators are used for the radiotherapy of eye malignancies such as melanomas. The producer (BEBIG GmbH) declares ±30% dose uncertainty in the applicator certificate. There is an obvious need to overcome this large imprecision. Our goal is to establish a method that is fast and reliable and which reduces dose uncertainty to below ±10%. Materials and methods: A pleksiglas phantom containing spherical calottes was constructed for this purpose. It allows measurements of surface homogeneity, absolute surface dose rates and depth doses in 2 mm steps, on and off the symmetry axis. Very small, 1x1x1 mm 3 thermoluminescent dosimeters (TLD) were chosen as dosimeters. They have to be calibrated adequately for Ru-Rh dosimetry. To do that, 6 0C o/electron field response ratio of TLDs was investigated and correction factors were established. Doses to the base of optic nerve were considered. Results: The 6 0C o/electron beam response ratio of TLDs is in agreement with measured and calculated results reported by other authors (for LiF TLD-100 of different dimensions). The measurements of surface dose rate homogeneity show deviations of up to 15% of the mean surface dose rate. However, surface inhomogeneities average out deeper in the phantom. Absolute surface dose rates were found lower than those declared by the producer by 6.2%, averaged over 8 applicators investigated. On and off axis depth doses are highly uniform over angle θ=40 degrees from symmetry axis, up to 6 mm in depth. Therefore, depth doses form spherical isodose surfaces within stated angle, spanning at least 1.47 steradians. Depth dose functions were interpolated to the measured data for practical routine use. Conclusions: The method developed here has overall combined uncertainty <±6%, and therefore reduces significantly uncertainty declared by the producer. Also, it proved to be stable on repeated measurements. (author)

  4. Equipment, measurement technique and annealing of LiF (TLD-100) in TL-dosimetry

    International Nuclear Information System (INIS)

    Unhjem, J.F.

    1987-01-01

    Results of variations in reference light, dark current, TL-signal and total background signal during a read-out series of LiF (TLD-100) crystals are presented. Also two annealing procedures are compared. The results indicate a good signal-to-noise ratio, E(S)/σ, and that a new annealing procedure takes less time to carry out. Because of the time-saving effect and the high signal-to-noise ratio, the new annealing procedure can be recommended

  5. Proposal of a postal system for Ir-192 sources calibration used in high dose rate brachytherapy with LiF:Mn:Ti thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Vieira, W.S.; Borges, J.C.; Almeida, C.E.V.

    1998-01-01

    A proposal in order to improve the brachytherapy quality control and to allow postal intercomparison of Ir-192 sources used in high dose rate brachytherapy has been presented. The LiF: Mn: Ti (TLD 100) detector has been selected for such purpose. The experimental array and the TLDs irradiation and calibration techniques, at the treatment units, have been specified in the light of more recent methodology of Ir-192 calibration sources. (Author)

  6. Study and determination of thermoluminescent properties of a new dosemeter based on α -Al2O3:C

    International Nuclear Information System (INIS)

    Rivera Montalvo, T.

    1993-01-01

    Study and determination of the thermoluminescent properties of a new dosimeter based on α -Al 2 O 3 :C. Dosimetric characteristics studied were: glow curve structure, sensitivity, reproducibility, TL response as function of dose, and fading. Each experimental data point represents the average value of at least five measurements. The new detectors exhibited two peaks in its glow curve at 383 and 493 K. The low temperature peak decayed at room temperature in a few hours. Sensitivity of α -Al 2 O 3 :C detectors to gamma radiation per unit of absorbed dose was 3 times that of LiF:Mg, Cu, P and 11 times that of CaSO 4 : Dy + PTFE; the last two detectors possess characteristics which make them appropriate for diverse applications in the field of radiation dosimetry, specially for environmental measurements. (Author)

  7. Quality control of the breast cancer treatments on Hdr brachytherapy with TLD-100

    International Nuclear Information System (INIS)

    Torres H, F.; De la Espriella V, N.; Sanchez C, A.

    2014-01-01

    An anthropomorphic Phantom, a female trunk, was built with a natural bone structure and experimental material coated, glycerin and water-based material called JJT to build soft tissue equivalent to the muscle of human tissue, and a polymer (styrofoam) to build the lung as critical organ to simulate the treatment of breast cancer, with high dose rate brachytherapy (Hdr) and sources of Ir-192. The treatments were planned and calculated for the critical organ: Lung, and injury of 2 cm in diameter in breast with Micro Selectron Hdr system and the software Plato Brachytherapy V 14.1 of the Nucletron (Netherlands) which uses the standard protocol of radiotherapy for brachytherapy treatments. The dose experimentally measured with dosimeters TLD-100 LiF: Mg; Ti, which were previously calibrated, were placed in the same positions and bodies mentioned above, with less than 5% uncertainty. The reading dosimeters was carried out in a Harshaw TLD 4500. The results obtained for calculated treatments, using the standard simulator, and the experimental with TLD-100, show a high concordance, as they are on average a ± 1.1% making process becomes in a quality control of this type of treatments. (Author)

  8. Quality control of the breast cancer treatments on Hdr brachytherapy with TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Torres H, F. [Universidad de Cordoba, Materials and Applied Physics Group, 230002 Monteria, Cordoba (Colombia); De la Espriella V, N. [Universidad de Cordoba, Grupo Avanzado de Materiales y Sistemas Complejos, 230002 Monteria, Cordoba (Colombia); Sanchez C, A., E-mail: franciscotorreshoyos@yahoo.com [Universidad de Cordoba, Departamento de Enfermeria, 230002 Monteria, Cordoba (Colombia)

    2014-07-01

    An anthropomorphic Phantom, a female trunk, was built with a natural bone structure and experimental material coated, glycerin and water-based material called JJT to build soft tissue equivalent to the muscle of human tissue, and a polymer (styrofoam) to build the lung as critical organ to simulate the treatment of breast cancer, with high dose rate brachytherapy (Hdr) and sources of Ir-192. The treatments were planned and calculated for the critical organ: Lung, and injury of 2 cm in diameter in breast with Micro Selectron Hdr system and the software Plato Brachytherapy V 14.1 of the Nucletron (Netherlands) which uses the standard protocol of radiotherapy for brachytherapy treatments. The dose experimentally measured with dosimeters TLD-100 LiF: Mg; Ti, which were previously calibrated, were placed in the same positions and bodies mentioned above, with less than 5% uncertainty. The reading dosimeters was carried out in a Harshaw TLD 4500. The results obtained for calculated treatments, using the standard simulator, and the experimental with TLD-100, show a high concordance, as they are on average a ± 1.1% making process becomes in a quality control of this type of treatments. (Author)

  9. On the determination of the post-irradiation time from the glow curve of TLD-100

    International Nuclear Information System (INIS)

    Weinstein, M.; German, U.; Dubinsky, S.; Alfassi, Z.B.

    2003-01-01

    The ratio of peak 3 to the sum of peaks 4 + 5 in TLD-100 was measured for various pre-irradiation and post-irradiation time periods, under conditions characteristic of routine personal dosimetry. It was confirmed that the value of this ratio depends only on the elapsed time between the prior readout and the present one, independent of the moment when the irradiation took place during the total time interval (storage time). This effect indicates that fading of peak 3 seems to be due mainly to changes in the unoccupied traps, and not to decay of trapped charges, being almost independent of the presence of electrons or holes in the traps. This observation leads to the conclusion that the suggestions in the past to use the decay of peak 3 in TLD-100 for the measurement of the elapsed time between irradiation and readout may have been wrong. On the other hand, the decay of peak 2 can be used to measure the elapsed time from irradiation, since the rate of decay is different when related to pre-irradiation and post-irradiation times, indicating a much higher decay rate of the trapped charges (Randall-Wilkins decay). However, because of the fast decay rate of peak 2, its use for determination of the elapsed time since irradiation is of little practical significance. (author)

  10. Measuring the absorbed dose in critical organs during low rate dose brachytherapy with 137 Cs using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Torres, A.; Gonzalez, P.R.; Furetta, C.; Azorin, J.; Andres, U.; Mendez, G.

    2003-01-01

    Intracavitary Brachytherapy is one of the most used methods for the treatment of the cervical-uterine cancer. This treatment consists in the insertion of low rate dose 137 Cs sources into the patient. The most used system for the treatment dose planning is that of Manchester. This planning is based on sources, which are considered fixed during the treatment. However, the experience has shown that, during the treatment, the sources could be displaced from its initial position, changing the dose from that previously prescribed. For this reason, it is necessary to make measurements of the absorbed dose to the surrounding organs (mainly bladder and rectum). This paper presents the results of measuring the absorbed dose using home-made LiF: Mg, Cu, P + Ptfe thermoluminescent dosimeters (TLD). Measurements were carried out in-vivo during 20 minutes at the beginning and at the end of the treatments. Results showed that the absorbed dose to the critical organs vary significantly due to the movement of the patient during the treatment. (Author)

  11. Measurement of depth dose factors for various 60-Co and X-ray beams using ion chambers and thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Milu, C.

    1983-06-01

    As the depth dose factors may vary with the type of 60 Co unit (or X-ray generator) several determinations in this direction were done. The depth doses (mGy/s) for 60 Co beam (SSD=80cm) for the depths 5,10,15 and 20 cm were 11.92, 8.25, 5.75 and resp. 4.10 for field size 10x10 cm and 12.70, 9.42, 6.63 and resp. 4.93 for field size 20x20 cm. In X-ray beam, the depth doses (mGy/s) for FSD=50 cm, open-end and field size 10 cm diam. were: 1.78, 0.66, 0.23 and 0.09 for 100 kV (0.143 mm HVL, in air) and depths 5, 10, 15 and resp. 20 cm; 2.61, 1.12, 0.46 and 0.19 for 135 kV and 4.13, 1.88, 0.88 and 0.40 for 180 kV. The quality of the radiation at different depths in the water phantom was determined using a tandem TLD within Cu sleeve and TLD without Cu sleeve. The values obtained ranged from 0.018 mm Cu for 100 kV to 0.170 for 180 kV at depth 5 cm. All determinations were done using an IAEA perspex water tank and Harshaw extruded LiF as detectors. An intercomparison using LiF powder capsules prepared and sent by the IAEA Dosimetry Laboratory was performed too, in order to check the consistency of thermoluminescent dosimetry systems

  12. Din - an indiviual neutron dosemeter

    International Nuclear Information System (INIS)

    Buxerolle, M.

    1987-09-01

    An albedo neutron dosemeter with 6 LiF and 7 Lif thermoluminescent detectors has been developed. A cadmium shield limits the effect of the distance from the body to the dosemeter and the effect of thermal neutrons scattered by the surroundings. The thickness of the cadmium filter has been adjusted so that the response is about the same for thermal neutrons (maxwellian) and epithermal neutrons (1/E spectrum with the energy E [fr

  13. Results of the EURATOM programme for comparison of individual dosemeters

    International Nuclear Information System (INIS)

    Julius, H.W.

    1976-01-01

    The results of the EURATOM dosemeter comparison-program for dosemeters used in the member states are given. Especially the results obtained in the Netherlands are examined and evaluated. The design and characteristics of the badge developed by the TNO-RD which are based on a thermoluminescent dosemeter are given

  14. Exposure levels to radiation in a nuclear medicine laboratory: measurements with thermoluminescence dosemeters; Niveles de exposicion a la radiacion en un laboratorio de medicina nuclear: mediciones con dosimetros de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz J, A. [Departamento de Medicina Nuclear del Instituto nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico D.F. (Mexico)

    2000-07-01

    Since 1996 in the Nuclear medicine Department and another routine and research departments of the National Institute of Medical and Nutrition Sciences (INCMNSZ) are working at least with 12 radioactive sources opened and sealed. However, it was unknown if with the Tl personal dosemeters with lithium fluoride crystals (LiF), could be possible to receive information about the equivalent dose for each radionuclide or if there was some radionuclide that by being low energy emissor or beta energy emissor, it did not represent an ionization power sufficient to excite the crystals of the thermoluminescent dosemeters (DTL). In this work the obtained results with control dosemeters of diverse source opened or sealed are shown, which were put at 1 cm of the LiF crystals during a time exposure 18 hours. Therefore the objective of this work is to verify which sources excite or not to DTL crystals and taking the pertinent safety measures for each radionuclide. The conclusion is that the majority of dosemeters were excited by beta or gamma radiation of the radionuclides and that LiF crystals are able to receive equivalent doses until 1200 mSv, being this a guarantee for the staff, that in an any moment could be exposed to high dose in his working day. Also it was corroborated that the radionuclides more energizer are: iodine-131, iodine-125 and sodium-22 while the phosphorus-32 must be managed with careful, since the exposure to hands can result significant, just like the technetium-99m ({sup 99m} Tc). (Author)

  15. Difference between the mechanisms of peak formation of dosimetric TL(5) and 6 and 7 of TLD-100

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da; Caldas, L.V.E.

    1986-01-01

    It is studied the best model to explain the peak formation of TL 5,6 and 7 of TLD-100. The mission curves of the irradiated material were compared at environmental temperature and at 77 0 K. (E.G) [pt

  16. 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.

  17. Measurement of the dose to the family members taking care of thyroid cancer patients undergoing I-131 therapy in nuclear medicine using TLD-100

    International Nuclear Information System (INIS)

    Zehtabian, M.; Dehghan, N.; Danaei Ghazanfarkhani, M.; Haghighatafshar, M.; Sina, S.

    2017-01-01

    The family members or friends of the patients undergoing treatment using radioiodine in nuclear medicine are inevitably exposed to ionization radiation. The purpose of this study is measurement of the dose received by the people taking care of the thyroid cancer patients treated by 131 I. For this purpose, the dose amounts received by 29 people accompanying patients were measured using thermoluminescence dosimeters. A badge containing three TLD-100 chips was given to each caregiver. The people were asked to wear the badges for 24 days, when they are taking care of the patients. Finally the dose to each person was estimated by averaging the readings of the three TLDs. The measured dose amounts to the people were compared with the recommendations of international commissions. According to the results obtained in this study, the amounts of dose received by the caregivers were between 0.03 and 0.38 mSv, with the average of 0.12 mSv. By comparison of the results of this study with the recommendations of International Commission on Radiological Protection (ICRP), it can be observed that the dose to family members of the patients is less than the dose constraints. However, it is recommended that the caregivers be aware of the radiation protection principles in order to reduce their dose. (authors)

  18. Personal dosimetry TLD 100 in orthopedic surgeons exposed to ionizing radiation in Bogota - Colombia

    International Nuclear Information System (INIS)

    Sierra C, B. Y.; Jimenez, Y.; Plazas, M. C.; Eslava S, J.; Groot R, H.

    2014-08-01

    Orthopedic surgeons should be considered as professionals occupationally exposed to ionizing radiation, for using C arc (fluoroscope) an equipment of X type radiation emission, during surgical procedures for imaging generation. Some health institutes, use of C arc under uncontrolled circumstances, such a lack of dosimetry control, incomplete or absence of personnel protective elements and protective measures, which in turn, lead to a high exposition to the personnel. Materials and methods. Study of double match cohort by age and gender, was conducted, in four health institutions of second and third level of attention in Bogota city. Personal dosimetry measurements with TLD-100 dosimetry crystals in both cohorts and environmental dosimetry in each of operation rooms used for orthopedic procedures, were carry out during six months of follow up. Dosimetry crystals were read in a Harshaw 4500 - Bicron equipment, in the Medical Physics Laboratory of National University of Colombia. Results. Dosimetry measurements are compatibles with those of occupationally exposed personnel 3.44 mSv/6 m CI 95% (1.66-3.99), even does not overpass ICRP recommendations, are higher as were expect at the beginning of the study. The median of effective accumulative dose in thorax is 3,4 mSv CI 95% (1,66-3,99), higher in comparison with neck value 2,7 mSv CI 95% (1,73-3,80) and hand dosimetry 1,42 mSv CI 95% (0,96-2,34). Conclusions: Orthopedic surgeons should be considered occupational exposed to ionizing radiation, who has to accomplish to the radiological protection measures, dosimetric follow up and maintenance of the used X ray equipment. It was confirm throughout this study that dosimetry shows higher levels as expected at the beginning of the study, compatible with occupationally exposed personnel. (Author)

  19. TLD-100 glow-curve deconvolution for the evaluation of the thermal stress and radiation damage effects

    International Nuclear Information System (INIS)

    Sabini, M.G.; Bucciolini, M.; Cuttone, G.; Guasti, A.; Mazzocchi, S.; Raffaele, L.

    2002-01-01

    In this work, the dose response of TLD-100 dosimeters has been studied in a 62 MeV clinical proton beams. The signal versus dose curve has been compared with the one measured in a 60 Co beam. Different experiments have been performed in order to observe the thermal stress and the radiation damage effects on the detector sensitivity. A LET dependence of the TL response has been observed. In order to get a physical interpretation of these effects, a computerised glow-curve deconvolution has been employed. The results of all the performed experiments and deconvolutions are extensively reported, and the TLD-100 possible fields of application in the clinical proton dosimetry are discussed

  20. TLD-100 glow-curve deconvolution for the evaluation of the thermal stress and radiation damage effects

    CERN Document Server

    Sabini, M G; Cuttone, G; Guasti, A; Mazzocchi, S; Raffaele, L

    2002-01-01

    In this work, the dose response of TLD-100 dosimeters has been studied in a 62 MeV clinical proton beams. The signal versus dose curve has been compared with the one measured in a sup 6 sup 0 Co beam. Different experiments have been performed in order to observe the thermal stress and the radiation damage effects on the detector sensitivity. A LET dependence of the TL response has been observed. In order to get a physical interpretation of these effects, a computerised glow-curve deconvolution has been employed. The results of all the performed experiments and deconvolutions are extensively reported, and the TLD-100 possible fields of application in the clinical proton dosimetry are discussed.

  1. Thermoluminescence of LiF: Mg, Ti between 77 and 315 K

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da.

    1989-01-01

    A special thermoluminescent system was developed. It is able to operate right from liquid nitrogen temperature and also permits the determination of the sample thermoluminescent emission spectrum. Using this system, the thermoluminescence displayed by 77 K irradiated LiF:Mg,Ti (TLD-100), from the irradiation temperature to 315 K, was studied. In this temperature range seven glow peaks, at 139, 153, 194, 240, 260, 283 and 300 K, were determined. (author)

  2. Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.

    Directory of Open Access Journals (Sweden)

    Guerda Massillon-J L

    Full Text Available This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK and a modified linear accelerator (linac for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (MD-V2-55, alanine and thermoluminescent (TLD-100 dosimeters and compared with conventional dosimetry systems. Detectors were calibrated in terms of absorbed dose to water in (60Co gamma-ray and 6 MV x-ray reference (10×10 cm(2 fields using an ionization chamber calibrated at a standards laboratory. Absorbed dose to water rate computed with MD-V2-55 was higher than that obtained with the others dosimeters, possibly due to a smaller volume averaging effect. Ratio between the dose-rates determined with each dosimeter and those obtained with the film was evaluated for both treatment modalities. For the LGK, the ratio decreased as the dosimeter size increased and remained constant for collimator diameters larger than 8 mm. The same behaviour was observed for the linac and the ratio increased with field size, independent of the dosimeter used. These behaviours could be explained as an averaging volume effect due to dose gradient and lack of electronic equilibrium. Evaluation of the output factors for the LGK collimators indicated that, even when agreement was observed between Monte Carlo simulation and measurements with different dosimeters, this does not warrant that the absorbed dose to water rate in the field was properly known and thus, investigation of the reference dosimetry should be an important issue. These results indicated that alanine dosimeter provides a high degree of accuracy but cannot be used in fields smaller than 20 mm diameter. Gafchromic film can be considered as a suitable methodology for reference dosimetry. TLD dosimeters are not

  3. Comparison of the responses of TLD-100 and radiochromic films exposed to X-rays of low energy in a radiodiagnostic clinical treatment

    International Nuclear Information System (INIS)

    Castro, M.; Mesa, F.; Sosa, M.

    2007-01-01

    Full text: In this work a comparison of the responses of a TLD-100 and a radiochromic film exposed to a low energy X-ray beam is presented. X-rays in the range of 20 to 120 KV from a clinical machine at the radiodiagnostic unit of the IMSS-Tl hospital in Leon were used. The processes of calibration of both the TLD-100 and the radiochromic films are also discussed. (Author)

  4. TL response of LiF: Mg, Cu, P dosemeters in function of the photon energy; Respuesta TL de dosimetros de LiF: Mg, Cu, P en funcion de la energia del foton

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Furetta, C. [Universita degli Studi di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185 Roma (Italy)

    2005-07-01

    In this work the obtained results of studying the response of dosemeters of LiF: Mg, Cu, P + Ptfe, developed in the ININ, commercial dosemeters GR200A (LiF: Mg, Cu, P) of chinese manufacture and TLD-100 (LiF: Mg, Ti) US are presented, when irradiating them with X rays 16, 24, 34.5, 42, 100 and 145 keV of effective energy, with gamma rays of 662 keV ({sup 137} Cs) and 1252 keV ({sup 60} Co). The results are presented in function of the sensitivity that the dosemeters showed normalized to gamma radiation of {sup 60} Co. It was appreciated that the dosemeters more equivalent to the tissue, they were those of LiF: Mg, Cu, P + Ptfe, while the less equivalent ones were the TLD-100. (Author)

  5. The influence of temperature and humidity on the stability of the response of different thermoluminescent detectors

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da

    1989-01-01

    Fading results are presented for thermoluminescent detectors for temperatures of 20, 35 and 50 0 C and for relative humidities of 50 and 90% during storage periods of up to 30 days. The thermoluminescent detectors investigated were LiF:Mg,Ti(TLD-100 and TLD-700), CaF 2 :Dy(TLD-200) and Li 2 B 4 O 7 :Mn,Si. These detectors are very commonly used in personnel monitoring. (author)

  6. Comparison of two models for the X-ray dispersion produced in a Novillo Tokamak with measurements make with thermoluminescent dosemeters; Comparacion de dos modelos para la dispersion de rayos X producidos en un Novillo Tokamak con mediciones efectuadas con dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Flores O, A.; Castillo, A.; Barocio, S.R.; Melendez L, L.; Chavez A, E.; Cruz C, G.J.; Lopez, R.; Olayo, M.G.; Gonzalez M, P. [Instituto Nacional de Investigaciones Nucleares, 52045 Salazar, Estado de Mexico (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana Iztapalapa, 09340 Mexico D.F. (Mexico)

    1999-07-01

    It was presented the results to study about the X-ray dispersion produced in the Novillo Tokamak using thermoluminescent dosemeters (DTL). The measurements were make in the equatorial plane of Tokamak, along twelve radial directions. The dispersion is observed due to the radiation interaction with walls surrounding the machine. It was proposed two types of heuristic mathematical methods for describing the X-ray dispersion, comparing them with the experimental data obtained with Dtl. The predictions of both models are adjusted well to the experimental data. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-01

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

  8. Production of thermoluminescent dosemeters based on MgB{sub 4}O{sub 7}: Dy and MgB{sub 4}O{sub 7}: Tm; Producao de dosimetros termoluminescentes a base de MgB{sub 4}O{sub 7}: Dy e MgB{sub 4}O{sub 7}: Tm

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Luiza Freire de; Souza, Divanizia N., E-mail: luizaf25@hotmail.com, E-mail: divanizi@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Programa de Pos-Graduacao em Fisica

    2013-07-01

    The thermoluminescent dosimetry (TL) is a well-established technique for the detection of ionizing radiation in hospitals, clinics, and industrial establishments where there is the need to quantify the radiation. For this practice is require the use phosphors which are sensitive to radiation. Some phosphors are already commonly used in this practice, for example, TLD-100 (LiF: Mg, Ti), CaSO{sub 4}:Tm and CaSO{sub 4}:Dy. A compound that was most recently introduced in dosimetry and has many advantageous features to detect neutrons, electrons and gamma is the magnesium tetraborate (MgB{sub 4}O{sub 7}), but the undoped material is not good for dosimetry, since signal does not show satisfactory thermoluminescence. The present work presents the analysis of the compound MgB{sub 4}O{sub 7} when doped with rare earth elements, thulium (Tm) and dysprosium (Dy). The production of MgB{sub 4}O{sub 7}: Dy and MgB{sub 4}O{sub 7}: Tm occurred under acidic conditions. Following the process of crystal growth, several tests were made on phosphors produced to verify the quality of materials as TL dosimeter. Initially, was made the identification of the crystalline phases found in the material, using the technique of X-ray diffractometry, and then were evaluated and compared the TL emission curves of the crystals with two different types of dopants, to this, the samples were irradiated with different radiation sources: {sup 137}Cs (0,66 MeV), {sup 60}Co (1.25 MeV) and X-rays (0.41 MeV) and based on the results was evaluated the energy dependence of phosphors. Another characteristic analyzed, was the decay of TL signal for the material (fading). The results show that the material can be an excellent TL dosimeter when doped with rare earth elements Dy and Tm. (author)

  9. Passive dosemeter

    International Nuclear Information System (INIS)

    Hassib, G.; Piesch, E.

    1981-01-01

    The dosemeter will be used for the detection of radon and thoron as well as their daughter products. It consists of two chambers with nuclear trace or alpha detectors. Both chambers are connected with one another at their front sides with a filter arranged in between. One of the chambers has got lateral openings, it is used as a diffusion chamber. In the other chamber exclusively radon and thoron are detected. (DG) [de

  10. Use of MCNP to compare the response of dose deposited in the TLD 100, TLD 600 and TLD 700 in radiation fields due to {sup 60}Co and {sup 241}AmBe source; Uso do MCNP para comparacao das respostas de dose depositada nos TLD 100, TLD 600 e TLD 700 em campos de irradiacao devido a fontes de {sup 60}Co e {sup 241}AmBe

    Energy Technology Data Exchange (ETDEWEB)

    Cavalieri, Tassio A.; Castro, Vinicius A.; Siqueira, Paulo T.D., E-mail: tassio.cavalieri@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-08-15

    The successes of Boron Neutron Capture Therapy (BNCT) depend on the ability to deliver an adequate irradiation field to the target cells. Neutron beams used in BNCT are mostly driven from reactors and therefore, not only have a neutron energy range which far exceeds the thermal region but also do have a great gamma component. Beam characterization and dosimetry are consequently one of the essential procedures to be overcome to properly apply this technique. One of the methods currently used in mixed field (field containing both neutron and gamma) characterization, lies on the use of a pair of detectors with distinct responses to each beam component. But this technique needs to be better understood of how each thermoluminescent dosimeter (TLD) behaves in a mixed field or in a pure field. This work presents the results of a set of simulations performed in order to analyze the response of three ordinary types of TLDs - TLD 100, TLD 600 and TLD 700 - submitted to different irradiation fields from a Cobalt source and an Americium-Beryllium source inside a paraffin disk. And is also a possible method for performing the selection and calibration of theses TLDs. (author)

  11. The right choice: extremity dosemeter for different radiation fields

    International Nuclear Information System (INIS)

    Brasik, N.; Stadtmann, H.; Kindl, P.

    2005-01-01

    Full text: Measurements of weakly penetrating radiation in personal dosimetry present problems in the design of suitable detectors and in the interpretation of their readings. For the measurement of the individual beta radiation dose, personal dosemeter for the fingers/tips are required. In general, the dosemeters currently used for personal monitoring of beta and low energy photon doses suffer from an energy threshold problem because the detector and/or the filter are too thick. TLDs of a standard thickness can seriously underestimate personal skin doses, especially in external fields of weakly penetrating radiation fields. LiF:Mg, Cu, P is a promising TL material which allows the production of thin detectors with sufficient sensitivity. Dosimetric properties of two different types of extremity dosemeters, designed to measure the personal dose equivalent Hp(0.07), have been compared: LiF:Mg, Ti (TLD100) and LiF:Mg, Cu, P (TLD700H). The first one consists of 100 mg.cm -2 LiF:Mg, Ti (TLD 100) chip and a 35mg. cm -2 cap, the other consists of a 7mg. cm -2 layer of LiF:Mg, Cu, P (TLD-700H) powder and a 5mg. cm -2 cap. The evaluation was done in two steps: performance tests (ISO-12794) and measurements in real workplaces. In the first step type test results for beta calibration were compared. In addition calibration for low energy photon radiation according to ISO 4037-3 was carried out. In the second step, simultaneous measurements with both types of dosemeters were performed at workplaces, where radiopharmaceuticals containing different radioisotopes are prepared and applied. Practices in these fields are characterized by handling of high activities at very small distances between source and skin. The results from the comparison of the two dosemeter types are presented and analyzed with respect to different radiation fields. Experiments showed a satisfactory sensitivity for the thinner dosemeter (TLD 700H) for detecting beta radiation at protection levels and a good

  12. Characteristics of dosemeter types for skin dose measurements in practice

    International Nuclear Information System (INIS)

    Van, D. J.; Bosmans, H.; Marchal, G.; Wambersie, A.

    2005-01-01

    A growing number of papers report deterministic effects in the skin of patients who have undergone interventional radiological procedures. Dose measurements, and especially skin dose measurements, are therefore increasingly important. Methods and acceptable dosemeters are, however, not clearly defined. This paper is the result of a literature overview with regard to assessing the entrance skin dose during radiological examinations by putting a dosemeter on the patient's skin. The relevant intrinsic characteristics, as well as some examples of clinical use of the different detector types, are presented. In this respect, thermoluminescence, scintillation, semiconductor and film dosemeters are discussed and compared with respect to their practical use. (authors)

  13. Dosimetric analysis using glasses TLD-100 Lif; Mg; TI for the optimization of the quality control programs in radio surgery stereo tactic

    International Nuclear Information System (INIS)

    Maldonado, J. C; Plazas, M. C.; Dussan, R.; Conrado, Z.; Pena, G.; Jimenez, E.; Hakim, F.; Bermudez, S.

    2001-01-01

    The conditions of Stereo Tactic Radio Surgery treatments are simulated by means of the use of thermo luminescent glasses TLD-100 LiF; Mg; Ti placed in mannequins, to demonstrate that the doses received by the patients, either in the fractioned or in the mono fractioned techniques, are over the 500cGy, making urgent the use of a reliable dosimetric method [es

  14. Electron beam energy monitoring using thermoluminescent dosimeters and electron back scattering

    International Nuclear Information System (INIS)

    Nelson, Vinod; Gray, Alison

    2013-01-01

    Periodic checks of megavoltage electron beam quality are a fundamental requirement in ensuring accurate radiotherapy treatment delivery. In the present work, thermoluminescent dosimeters (TLDs) positioned on either side of a lead sheet at the surface of a water equivalent phantom were used to monitor electron beam quality using the electron backscattering method. TLD100 and TLD100H were evaluated as upstream detectors and TLD200, TLD400 and TLD500 were evaluated as downstream detectors. The evaluation assessed the test sensitivity and correlation, long and short term reproducibility, dose dependence and glow curve features. A prototype of an in-air jig suitable for use in postal TLD dose audits was also developed and an initial evaluation performed. The results indicate that the TLD100-TLD200 combination provides a sensitive and reproducible method to monitor electron beam quality. The light weight and easily fabricated in-air jig was found to produce acceptable results and has the potential to be used by radiation monitoring agencies to carry out TLD postal quality assurance audits, similar to audits presently being conducted for photon beams. -- Highlights: ► Monitoring electron beam quality via electron backscattering was investigated. ► Different thermoluminescent materials were evaluated as detectors. ► A TLD100-TLD200 combination produced the most sensitive and reproducible results. ► An in-air jig was evaluated to allow measurements via postal dose audits

  15. Dosimetric intercomparison in Cobalt 60 unities using TLD-100 crystals and CaSO{sub 4}: Dy + Ptfe; Intercomparacion dosimetrica en unidades de cobalto 60 usando cristales de TLD-100 y CaSO{sub 4}: Dy + PTFE

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E. [Universidad Autonoma Metropolitana Xochimilco, Mexico D.F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana Iztapalapa, Mexico D.F. (Mexico); Perez P, M.A. [Instituto Nacional de Cancerologia, Mexico D.F. (Mexico); Castillo H, M. [Centro Medico Nacional 20 de Noviembre, ISSSTE, Mexico D.F. (Mexico); Flores F, F. [Unidad de Oncologia, Centro Medico Nacional, IMSS, Mexico D.F. (Mexico); Guzman R, L.V. [Unidad de Oncologia, Hospital General de Mexico, Mexico D.F. (Mexico)

    1999-07-01

    The purpose of this work is to design and construct a phantom in basis of thermoplastic polymer of methyl methacrylate that is reutilizable and which allows to do an analysis of the absorbed doses in thermoluminescent crystals (Tl) exposed to cobalt 60 to establish the dosimetric intercomparison in cobalt units which allows to do the follow-up of the Quality assurance programs, standardization of calibration procedures, dosimetry and TLD post intercomparison in radiotherapy. This work allows also prove new thermoluminescent materials of national manufacture developed by Juan Azorin and collaborators as the CaSO{sub 4}: Dy + Ptfe. This is a first study which is realized in Mexico with the system crystal-phantom for aims to intercomparison in cobalt 60 units. In this work participate eight unities of cobalt 60 of different trades belonging at four radiotherapy centers. The results of the dose intercomparison of the eight unities of cobalt 60 were in the range 0.95-1.13, taking in account that the values between 0.95 and 1.05 were considered acceptable in terms of the requirements by the standing legislation. (Author)

  16. Dosimetric intercomparison in Cobalt 60 unities using TLD-100 crystals and CaSO4: Dy + Ptfe

    International Nuclear Information System (INIS)

    Gaona, E.; Azorin N, J.; Perez P, M.A.; Castillo H, M.; Flores F, F.; Guzman R, L.V.

    1999-01-01

    The purpose of this work is to design and construct a phantom in basis of thermoplastic polymer of methyl methacrylate that is reutilizable and which allows to do an analysis of the absorbed doses in thermoluminescent crystals (Tl) exposed to cobalt 60 to establish the dosimetric intercomparison in cobalt units which allows to do the follow-up of the Quality assurance programs, standardization of calibration procedures, dosimetry and TLD post intercomparison in radiotherapy. This work allows also prove new thermoluminescent materials of national manufacture developed by Juan Azorin and collaborators as the CaSO 4 : Dy + Ptfe. This is a first study which is realized in Mexico with the system crystal-phantom for aims to intercomparison in cobalt 60 units. In this work participate eight unities of cobalt 60 of different trades belonging at four radiotherapy centers. The results of the dose intercomparison of the eight unities of cobalt 60 were in the range 0.95-1.13, taking in account that the values between 0.95 and 1.05 were considered acceptable in terms of the requirements by the standing legislation. (Author)

  17. Determination of kinetic parameters in Tl dosemeters of LiF: Mg, Cu, P + PTFE developed in the ININ

    International Nuclear Information System (INIS)

    Basurto G, B.S.

    2002-01-01

    The objective of this work, is the one of determining the kinetic parameters of the dosemeter of LiF: Mg, Cu, P + Ptfe; starting from the curves Tl obtained at being irradiated with alpha radiation (α), beta (β) and gamma (γ). As like to compare its sensitivity with each radiation type, considering the sensitivity of the TLD-100 as the unit. In the Chapter 1, the fundamental structure of the matter is described, making emphasis in the different radiation types, and their interaction with this. In the Chapter 2, the units are described but used in the dosimetry of the radiation. In the Chapter 3, the basic concepts of the phenomenon of Tl are described and those are explained characteristic of the deconvolution method to determine the kinetics of the one phenomenon. In the Chapter 4, the methodology is detailed that was used in the elaboration of this thesis work, describing the material Tl that were considered like reference, as well as the sources of ionizing radiation, with those that the dosemeters were irradiated and the equipment in the one that the curves Tl was obtained. Reference is made to the software used to carry out the deconvolution of the curves Tl that were obtained in the one experimental development. In the Chapter 5, the obtained results of this study are presented, showing the tables of homogenization of dosemeters and the reading of the same one; they are observed the curves Tl obtained to different radiation doses (alpha, beta and gamma), the intensity Tl in function of the dose. Also they are tabulated, the obtained results in the kinetic parameters of the three different study materials (TLD-100H, USA; TLD-100, USA and LiF: Mg, Cu, P + Ptfe developed in the l.N.l.N). They are analyzed shortly for each material Tl their sensitivity to the ionizing radiation as well as their kinetic parameters. The obtained results showed that the Tl dosemeters of LiF: Mg,Cu,P + Ptfe, they presented a bigger sensitivity that the TLD-100 when being

  18. Acid dip for dosemeter

    International Nuclear Information System (INIS)

    Stewart, J.C.; McWhan, A.F.

    1982-01-01

    Background signal in a PTFE based dosemeter caused by impurities in the PTFE and in the active component such as lithium fluoride is substantially reduced by treating the dosemeter with acid. The optimum treatment involves use of hydrofluoric acid at room temperature for approximately one minute, followed by thorough washing with methanol, and finally drying. This treatment is best applied after the original manufacture of the dosemeters. It may also be applied to existing dosemeters after they have been in use for some time. The treatment produces a permanent effect in reducing both the light induced signal and the non-light induced signal. The process may be applied to all types of dosemeter manufactured from PTFE or other plastics or resins which are able to resist brief exposure to acid. The treatment works particularly well with dosemeters based on PTFE and lithium fluoride. It is also applicable to dosemeters based on calcium sulphate, lithium borate and magnesium borate. Acids which may be used include hydrofluoric, hydrochloric, nitric, phosphoric and sulphuric. (author)

  19. Alarm personal dosemeter

    International Nuclear Information System (INIS)

    Nunomiya, Tomoya; Yamauchi, Hideshi; Shibata, Tetsuo

    2007-01-01

    Fuji Electric advanced the development of the conventional alarm personal dosemeter (APD) by adopting JIS Z 4312 (2002), which reflects IEC61526 (1998), and by improving the radiation performance characteristics, electromagnetic performance characteristics and mechanical performance characteristics of the APD (acquiring a CE marking). This new dosemeter will target overseas market in the future. The APD is a suitable dosemeter for detecting and monitoring radiation exposure to personnel working in the controlled areas of nuclear facilities, such as nuclear power stations. The APD product line includes 'gamma ray', 'gamma ray + beta ray' and 'gamma ray + neutron' models. (author)

  20. Dose equivalent response of personal neutron dosemeters as a function of angle

    International Nuclear Information System (INIS)

    Tanner, J.E.; McDonald, J.C.; Stewart, R.D.; Wernli, C.

    1997-01-01

    The measured and calculated dose equivalent response as a function of angle has been examined for an albedo-type thermoluminescence dosemeter (TLD) that was exposed to unmoderated and D 2 O-moderated 252 Cf neutron sources while mounted on a 40 x 40 15 cm 3 polymethylmethacrylate phantom. The dosemeter used in this study is similar to many neutron personal dosemeters currently in use. The detailed construction of the dosemeter was modelled, and the dose equivalent response was calculated, using the MCNP code. Good agreement was found between the measured and calculated values of the relative dose equivalent angular response for the TLD albedo dosemeter. The relative dose equivalent angular response was also compared with the values of directional and personal dose equivalent as a function of angle published by Siebert and Schuhmacher. (author)

  1. Electron scattering effects on absorbed dose measurements with LiF-dosemeters

    International Nuclear Information System (INIS)

    Bertilsson, G.

    1975-10-01

    The investigation deals with absorbed dose measurements with solid wall-less dosemeters. Electron scattering complicates both measurement of absorbed dose and its theoretical interpretation. The introduction of the dosemeter in a medium causes perturbations of the radiation field. This perturbation and its effect on the distribution of the absorbed dose inside the dosemeter is studied. Plane-parallel LiF-teflon dosemeters (0.005 - 0.1 g.cm -2 ) are irradiated by a photon beam ( 137 Cs) in different media. The investigation shows that corrections must be made for perturbations caused by electron scattering phenomena. Correction factors are given for use in accurate absorbed dose determinations with thermoluminescent dosemeters. (Auth.)

  2. The use of active personal dosemeters as a personal monitoring device: Comparison with TL dosimetry

    International Nuclear Information System (INIS)

    Boziari, A.; Koukorava, C.; Carinou, E.; Hourdakis, C. J.; Kamenopoulou, V.

    2011-01-01

    The use of active personal dosemeters (APDs) not only as a warning device but also, in some cases, as an official and hence stand-alone dosemeter is rapidly increasing. A comparison in terms of dose, energy and angle dependence, among different types of APD and a routinely used whole-body thermoluminescence dosemeter (TLD) has been performed. Significant differences were found between the TLD readings and mainly some not commonly used APDs. The importance of choosing the best adapted APD according to the radiation field characteristics is pointed out. (authors)

  3. Thermoluminescent dosimeter

    International Nuclear Information System (INIS)

    Stewart, J.C.

    1981-01-01

    A dosimeter of the type in which two plates of plastics material are bonded together with a layer of thermoluminescent material trapped between is described. The device is made by sprinkling granular thermoluminescent material over areas of a plastics plate which has adhesive on it, removing excess material and then applying a second layer of plastics material over the first layer, and over the thermoluminescent material, and bonding it to complete the dosimeter. (author)

  4. Application of the Cavity theory in the calibration of the powder TLD-100 for energies of 60 Co, 137 Cs, 192 Ir and RX 50, 250 k Vp

    International Nuclear Information System (INIS)

    Loaiza C, S.P.; Alvarez R, J.T.

    2006-01-01

    A powder lot TLD-100 (LiF:Mg,Ti) in absorbed dose terms in water D w for the following radiation sources: 60 Co, 137 Cs and RX 50 and 250 k Vp is calibrated; to continuation is made a lineal interpolation of the TLD response in function of the effective energy of the sources to calibrate a source of 192 Ir. The calibration of those fields in D w are carried out with aid of the Bragg-Gray cavity theory, the one which finds implicit in the following protocols: IAEA-TRS 398 for the 60 Co and the AAPM TG61 for X Rays of 50 and 250 k Vp. Additionally the AAPM protocol TG43 to determine the D w in function of the kerma intensity S k in the case of the 137 Cs is used. The calibration curves for the response of the TLD-100 R TLD vs D w , corresponding to each one of the sources already mentioned are constructed. The R TLD vs D w by least heavy square by means of a second order polynomial that corrects the supralineality of the response is adjusted. The curves are validated by lack of LOF adjustment and by the Anderson Darling normality test. Later the factors of sensitivity (F s ) for the sources of 192 Ir: Micro Selectron and Vari Source are interpolated, used respectively in the A and B hospitals for treatments of brachytherapy of high dose rate (HDR), the expanded uncertainties associated to the D w and F s are also determined. Finally, an acrylic phantom and a couple of capsules are already sent to the hospitals mentioned, to verify a nominal D w of 2 Gy, in a case an underestimate in 5.5% in the imparted D w and in other an overestimation in a range of -1.5 to -8.0% was obtained. The obtained results in this work establish the bases for the development of a national dosimetric quality control program for brachytherapy of HDR with sources of 192 Ir. (Author)

  5. Passive personal radon dosemeter

    International Nuclear Information System (INIS)

    Djeffal, S.; Allab, M.

    1993-01-01

    The dosimetry laboratory of the Radiation Protection and Safety Centre in Algiers has developed a passive integrating radon personal dosemeter. This dosemeter is designed to be used in atmospheres where high humidity is present such as in mines. It also excludes radon progeny, thoron and its decay products and detritus through a filter membrane. It has the advantages of being simple, cheap and robust. Based on the diffusion principle, it consists of an enclosed small sized chamber into which radon diffuses and which contains a track detector for the registration of alpha particles. The number of alpha particle tracks recorded is proportional to the time integral of the radon gas concentration external to the dosemeter. Theoretical studies were undertaken to determine the optimum dimensions of the diffusion chamber. The dosemeter response was studied by varying the volume and the shape of the chamber and the filter membrane thickness. The diffusion chamber adopted consists of a cylindrical aluminium container of approximate height 4 cm and diameter 3 cm. The reproducibility of the dosemeter response has also been tested. The calibration of these passive personal radon dosemeters was performed at the National Radiological Protection Board (Harwell, UK) and the resulting sensitivity factor is about 2.5 and 1.6 tracks.cm -2 per kBq.m -3 .h for the detectors counted by means of an optical microscope and a spark counter respectively. (Author)

  6. Comparison of the calculated absorbed dose using the Cadplan™ treatment planning software and Tld-100 measurements in an Alderson-Rando phantom for a bronchogenic treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gutiérrez Castillo, J. G., E-mail: jggc59@hotmail.com [Departamento de Física, Hospital de Oncología, IMSS, CMN Siglo XXI, Cuauhtémoc 330 Col. Doctores (Mexico); Álvarez Romero, J. T., E-mail: trinidad.alvarez@inin.gob.mx, E-mail: fisarmandotorres@gmail.com, E-mail: victor.tovar@inin.gob.mx; Calderón, A. Torres, E-mail: trinidad.alvarez@inin.gob.mx, E-mail: fisarmandotorres@gmail.com, E-mail: victor.tovar@inin.gob.mx; M, V. Tovar, E-mail: trinidad.alvarez@inin.gob.mx, E-mail: fisarmandotorres@gmail.com, E-mail: victor.tovar@inin.gob.mx [SSDL, Departamento de Metrología ININ, Salazar, Estado de México 15245 (Mexico)

    2014-11-07

    To verify the accuracy of the absorbed doses D calculated by a TPS Cadplan for a bronchogenic treatment (in an Alderson-Rando phantom) are chosen ten points with the following D's and localizations. Point 1, posterior position on the left edge with 136.4 Gy. Points: 2, 3 and 4 in the left lung with 104.9, 104.3 and 105.8 Gy, respectively; points 5 and 6 at the mediastinum with 192.4 and 173.5 Gy; points 7, 8 and 9 in the right lung with 105.8, 104.2 and 104.7 Gy, and 10 at posterior position on right edge with 143.7 Gy. IAEA type capsules with TLD 100 powder are placed, planned and irradiated. The evaluation of the absorbed dose is carried out a curve of calibration for the LiF response (nC) {sup vs} {sup DW}, to several cavity theories. The traceability for the DW is obtained with a secondary standard calibrated at the NRC (Canada). The dosimetric properties for the materials considered are determined from the Hounsfield numbers reported by the TPS. The stopping power ratios are calculated for nominal spectrum to 6 MV photons. The percent variations among the planned and determined D in all the cases they are < ± 3%.

  7. Proposal of a postal system for Ir-192 sources calibration used in high dose rate brachytherapy with LiF:Mn:Ti thermoluminescent dosemeters; Proposta de um sistema postal para a calibracao de fontes de {sup 192} Ir, utilizadas em braquiterapia de alta taxa de dose, com dosimetros termoluminescentes de LiF: Mn: Ti

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, W.S.; Borges, J.C.; Almeida, C.E.V. [Instituto de Radioprotecao e Dosimetria. CNEN Caixa Postal 37750, 22780-160, Rio de Janeiro (Brazil)

    1998-12-31

    A proposal in order to improve the brachytherapy quality control and to allow postal intercomparison of Ir-192 sources used in high dose rate brachytherapy has been presented. The LiF: Mn: Ti (TLD 100) detector has been selected for such purpose. The experimental array and the TLDs irradiation and calibration techniques, at the treatment units, have been specified in the light of more recent methodology of Ir-192 calibration sources. (Author)

  8. Kerma determination in air on mamma by thermoluminescence

    International Nuclear Information System (INIS)

    Palacios P, L. L.; Rivera M, T.

    2009-10-01

    In this work the experimental results of the entrance exposition are shown and Kerma in air [mGy] in mamma obtained by irradiation of accreditation phantom of American College of Radiology (ACR). The irradiations were realized in a conventional mammography equipment of Hospital Juarez in Mexico; the technique used during the irradiations was of automatic exposition; the thickness for the phantom ACR obtained by the technique were of 4.2 and 4.5 cm; the kilo voltage pick was of 24 kV p , the time and the milli amperage per second variable. The measuring of Kerma in air was obtained with thermoluminescent dosemeters of solid state, of nano particles of zirconium dioxide prepared by the precipitation method. The dosemeters were homogenized previously in low energies of X-rays that are those used for mammography. The thermoluminescent dosemeters of ZrO 2 were calibrated by means of an ionization chamber for different expositions. The calibration curve is reported for the exposition and Kerma in air against thermoluminescent intensity obtained by reading of thermoluminescent dosemeters of ZrO 2 , as well as the technique employee for the Kerma determination in air and entrance exposition in mamma. (Author)

  9. Comparison test of electronic dosemeters

    International Nuclear Information System (INIS)

    Butterweck, G.; Zimmerli, H.P.; Wernli, C.

    2001-01-01

    To assist with a planned purchase of electronic dosemeters by the Swiss Federal Office for Civil Protection, the calibration laboratory of the Paul Scherrer Institute performed tests on 11 types of electronic dosemeters manufactured by 10 European and American companies. The technical specifications for the World Trade Organisation (WTO) tendering procedure were largely in accord with the specifications of the international standard IEC 61526. First tests were performed with samples from each type of dosemeter. The reproducibility of a dose of 0.1 mSv generated with 137 Cs radiation at a dose rate of 2.1 mSv.h -1 was found adequate for all tested dosemeter types. The response for environmental levels of radiation showed a large variation, indicating insufficient background correction of some dosemeters. A very high dose rate of 10 Sv.h -1 provoked faulty dose readings for more than half of the tested dosemeters. Dosemeter response for low-energy photon radiation was satisfactory for two of the tested dosemeter types. Four dosemeter types were selected for extended technical tests. Three samples of each of these dosemeter types were purchased. For drop and temperature tests the specifications of the WTO tendering procedure outranged the specification of the IEC standard. Whereas even at a temperature of -25 deg. C the tested dosemeters functioned normally, drops from a height of 2 m onto a wooden surface rendered the samples of two dosemeter types inoperative. (author)

  10. Personal dosimetry TLD 100 in orthopedic surgeons exposed to ionizing radiation in Bogota - Colombia; Dosimetria personal TLD 110 en medicos ortopedistas expuestos a radiacion ionizante en Bogota - Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Sierra C, B. Y.; Jimenez, Y. [Universidad Nacional de Colombia, Departamento de Fisica, Grupo de Fisica Medica, Carrera 45 No. 26-85, Bogota (Colombia); Plazas, M. C. [Hospital Universitario Fundacion Santa Fe de Bogota, Instituto de Oncologia Carlos Ardila Lulle, Calle 119, No. 7-90, 220246 Bogota (Colombia); Eslava S, J. [Universidad Nacional de Colombia, Instituto de Investigaciones Clinicas, Grupo Equidad en Salud, Carrera 45 No. 26-85, Bogota (Colombia); Groot R, H., E-mail: brigith.sierra@gmail.com [Universidad de los Andes, Laboratorio de Genetica Humana, Carrera 1 No. 18A -12, Bogota (Colombia)

    2014-08-15

    Orthopedic surgeons should be considered as professionals occupationally exposed to ionizing radiation, for using C arc (fluoroscope) an equipment of X type radiation emission, during surgical procedures for imaging generation. Some health institutes, use of C arc under uncontrolled circumstances, such a lack of dosimetry control, incomplete or absence of personnel protective elements and protective measures, which in turn, lead to a high exposition to the personnel. Materials and methods. Study of double match cohort by age and gender, was conducted, in four health institutions of second and third level of attention in Bogota city. Personal dosimetry measurements with TLD-100 dosimetry crystals in both cohorts and environmental dosimetry in each of operation rooms used for orthopedic procedures, were carry out during six months of follow up. Dosimetry crystals were read in a Harshaw 4500 - Bicron equipment, in the Medical Physics Laboratory of National University of Colombia. Results. Dosimetry measurements are compatibles with those of occupationally exposed personnel 3.44 mSv/6 m CI 95% (1.66-3.99), even does not overpass ICRP recommendations, are higher as were expect at the beginning of the study. The median of effective accumulative dose in thorax is 3,4 mSv CI 95% (1,66-3,99), higher in comparison with neck value 2,7 mSv CI 95% (1,73-3,80) and hand dosimetry 1,42 mSv CI 95% (0,96-2,34). Conclusions: Orthopedic surgeons should be considered occupational exposed to ionizing radiation, who has to accomplish to the radiological protection measures, dosimetric follow up and maintenance of the used X ray equipment. It was confirm throughout this study that dosimetry shows higher levels as expected at the beginning of the study, compatible with occupationally exposed personnel. (Author)

  11. 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)

  12. 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

  13. Requirements for personal dosemeters

    International Nuclear Information System (INIS)

    Busuoli, G.; Cavallini, A.

    1984-01-01

    External radiation monitoring equipment should yield reliable data of reasonable accuracy (at least to within ± 50%, as stipulated by ICRP). This degree of accuracy is considered adequate for personal dosimetry (monitoring), but is may desirable to use more accurate instruments or personal dosemeters since many factors influence the determination of the dose equivalent

  14. HOW DO HOSPITAL STERILISATION PROCEDURES AFFECT THE RESPONSE OF PERSONAL EXTREMITY RINGS AND OF EYE LENS TL DOSEMETERS?

    Science.gov (United States)

    Kopeć, Renata; Bubak, Anna; Budzanowski, Maciej; Sas-Bieniarz, Anna; Szumska, Agnieszka

    2016-09-01

    Stringent standards of hygiene must be applied in medical institutions, especially at operating blocks or during interventional radiology procedures. Medical equipment, including personal dosemeters that have to be worn by medical staff during such procedures, needs therefore to be sterilised. In this study, the effect of various sterilisation procedures has been tested on the dose response of extremity rings and of eye lens dosemeters in which thermoluminescent (TL) detectors (of types MTS-N and MCP-N, respectively) are used. The effects of medical sterilisation procedures were studied: by chemicals, by steam or by ultraviolet (UV), on the dose assessment by extremity rings and by eye lens dosemeters. Since it often happens that a dosemeter is accidentally machine-washed together with protective clothing, the effect of laundering on dose assessment by these dosemeters was also tested. The sterilisation by chemicals is mostly safe for TL detectors assuming that the dosemeters are waterproofed. Following sterilisation by water vapour, the response of these dosemeters diminished by some 30 %, irrespectively of the period of sterilisation; therefore, this method is not recommended. UV sterilisation can be applied to EYE-D™ eye lens dosemeters if their encapsulation is in black. The accidental dosemeter laundry in a washing machine has no impact on measured dose. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Dosimetric behavior of thermoluminescent dosimeters at low doses in diagnostic radiology; Comportamiento dosimetrico de dosimetros termoluminiscentes a bajas dosis en radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Del Sol F, S.; Garcia S, R.; Guzman M, J.; Sanchez G, D.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Ramirez R, G. [Hospital Juarez de Mexico, Av. IPN 5160, Col. Magdalena de las Salinas, 07760 Mexico D. F. (Mexico); Gaona, E., E-mail: susi2489@hotmail.com [Universidad Autonoma Metropolitana, Unidad Xochimilco, Calz. del Hueso 1100, Col. Villa Quietud, 04960 Mexico D. F. (Mexico)

    2015-10-15

    Thermoluminescent (Tl) characteristics of TLD-100, LiF:Mg,Cu,P, and CaSO{sub 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{sub 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{sub 4}: Dy). (Author)

  16. Application of the Cavity theory in the calibration of the powder TLD-100 for energies of {sup 60} Co, {sup 137} Cs, {sup 192} Ir and RX 50, 250 k Vp; Aplicacion de la Teoria de la Cavidad en la calibracion de polvo TLD-100 para energias de {sup 60} Co, {sup 137} Cs, {sup 192} Ir y RX 50, 250 kVp

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza C, S.P. [UAEM, Programa de Maestria en Fisica Medica, 50180, Toluca, Estado de Mexico (Mexico); Alvarez R, J.T. [ININ, 52750, Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: sandraplc_04@yahoo.com.mx

    2006-07-01

    A powder lot TLD-100 (LiF:Mg,Ti) in absorbed dose terms in water D{sub w} for the following radiation sources: {sup 60} Co, {sup 137} Cs and RX 50 and 250 k Vp is calibrated; to continuation is made a lineal interpolation of the TLD response in function of the effective energy of the sources to calibrate a source of {sup 192} Ir. The calibration of those fields in D{sub w} are carried out with aid of the Bragg-Gray cavity theory, the one which finds implicit in the following protocols: IAEA-TRS 398 for the {sup 60} Co and the AAPM TG61 for X Rays of 50 and 250 k Vp. Additionally the AAPM protocol TG43 to determine the D{sub w} in function of the kerma intensity S{sub k} in the case of the {sup 137} Cs is used. The calibration curves for the response of the TLD-100 R{sub TLD} vs D{sub w}, corresponding to each one of the sources already mentioned are constructed. The R{sub TLD} vs D{sub w} by least heavy square by means of a second order polynomial that corrects the supralineality of the response is adjusted. The curves are validated by lack of LOF adjustment and by the Anderson Darling normality test. Later the factors of sensitivity (F{sub s}) for the sources of {sup 192} Ir: Micro Selectron and Vari Source are interpolated, used respectively in the A and B hospitals for treatments of brachytherapy of high dose rate (HDR), the expanded uncertainties associated to the D{sub w} and F{sub s} are also determined. Finally, an acrylic phantom and a couple of capsules are already sent to the hospitals mentioned, to verify a nominal D{sub w} of 2 Gy, in a case an underestimate in 5.5% in the imparted D{sub w} and in other an overestimation in a range of -1.5 to -8.0% was obtained. The obtained results in this work establish the bases for the development of a national dosimetric quality control program for brachytherapy of HDR with sources of {sup 192} Ir. (Author)

  17. 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

  18. Principle and use of dosemeters

    International Nuclear Information System (INIS)

    Genet, S.; Ribaud, I.

    1997-01-01

    The institute of nuclear physics of Orsay is accepted by the Ministry of Labour to insure the surveillance of workers individual external exposure against the danger of ionizing radiations and to execute monitoring of radiation protection. The dosemeters studied in this report are the photographic film dosemeters ( for x rays, gamma rays and beta - rays), the trace detectors (fast neutrons) and the radio thermo luminescent dosemeters. For each type, the principle and how to use it are given. (N.C.)

  19. Estimation of DNA DSB radiation damage using a solid state nanodosimeters based on glow peak 5a in LiF:Mg,Ti (TLD-100)

    International Nuclear Information System (INIS)

    Oster, L.; Haddad, J.; Horowitz, Y.S.; Biderman, S.

    2002-01-01

    We demonstrate the viability of the concept of using existing molecular nano structures in TL solid-state nanodosimeters. The concept is based on mimicking radiobiology (specifically the ionization density dependence of double strand breaks in DNA) by using the similar ionization density dependence of simultaneous electron-hole capture in spatially correlated TC/LC pairs in the thermoluminescence of LiF:Mg, Ti. This simultaneous electron-hole capture has been shown to lead to ionization density dependence in the relative intensity of peak 5a to peak 5 similar to the ratio of DSBs to SSBs for low energy He ions. (authors)

  20. Determination of kinetic parameters in Tl dosemeters of LiF: Mg, Cu, P + PTFE developed in the ININ; Determinacion de parametros cineticos en dosimetros Tl de LiF: Mg, Cu, P + PTFE desarrollados en el ININ

    Energy Technology Data Exchange (ETDEWEB)

    Basurto G, B.S

    2002-07-01

    The objective of this work, is the one of determining the kinetic parameters of the dosemeter of LiF: Mg, Cu, P + Ptfe; starting from the curves Tl obtained at being irradiated with alpha radiation ({alpha}), beta ({beta}) and gamma ({gamma}). As like to compare its sensitivity with each radiation type, considering the sensitivity of the TLD-100 as the unit. In the Chapter 1, the fundamental structure of the matter is described, making emphasis in the different radiation types, and their interaction with this. In the Chapter 2, the units are described but used in the dosimetry of the radiation. In the Chapter 3, the basic concepts of the phenomenon of Tl are described and those are explained characteristic of the deconvolution method to determine the kinetics of the one phenomenon. In the Chapter 4, the methodology is detailed that was used in the elaboration of this thesis work, describing the material Tl that were considered like reference, as well as the sources of ionizing radiation, with those that the dosemeters were irradiated and the equipment in the one that the curves Tl was obtained. Reference is made to the software used to carry out the deconvolution of the curves Tl that were obtained in the one experimental development. In the Chapter 5, the obtained results of this study are presented, showing the tables of homogenization of dosemeters and the reading of the same one; they are observed the curves Tl obtained to different radiation doses (alpha, beta and gamma), the intensity Tl in function of the dose. Also they are tabulated, the obtained results in the kinetic parameters of the three different study materials (TLD-100H, USA; TLD-100, USA and LiF: Mg, Cu, P + Ptfe developed in the l.N.l.N). They are analyzed shortly for each material Tl their sensitivity to the ionizing radiation as well as their kinetic parameters. The obtained results showed that the Tl dosemeters of LiF: Mg,Cu,P + Ptfe, they presented a bigger sensitivity that the TLD-100 when

  1. Characterization of TLD-100 in powders for dosimetric quality control of 192 Ir sources used in brachytherapy of high dose rate

    International Nuclear Information System (INIS)

    Loaiza C, S.P.

    2007-01-01

    The Secondary Standard Dosimetric at the National Institute of Nuclear Research (ININ) calibrated a lot of powdered TLD-100 (LiF:Mg,Ti) in terms of absorbed dose to water D w for the energy of: 60 Co, 137C s, X rays of 250 and 50 kVp. Later on, it is carried out an interpolation of the calibration for the energy of the 192 Ir. This calibration is part of a dosimetric quality control program, to solve the problems of traceability for the measurements carried out by the users of 192 Ir sources employed in the treatments of High Dose Rate Brachytherapy (HDR) at the Mexican Republic. The calibrations of the radiation beams are made with the following protocols: IAEA TRS-398 for the 60 Co for D w , using a secondary standard ionization chamber PTW N30013 calibrated in D w by the National Research Council (NRC, Canada). AAPM TG-43 for D w in terms of the strength kerma Sk, calibrating this last one quantity for the 137 Cs radioactive source, with a well chamber HDR 1000 PLUS traceable to the University of Wisconsin (US). AAPM TG-61 for X ray of 250 and 50 kVp for D w start to Ka using field standard a Farmer chamber PTW 30001 traceable to K for the Central Laboratory of Electric Industries (CLEI, France). The calibration curves (CC) they built for the response of the powder TLD: R TLD vs D w : For the energy of 60 Co, 137 Cs, X rays of 250 and 50 kVp. Fitting them with the least square method weighed by means of a polynomial of second grade that corrects the supra linearity of the response. iii. Each one of the curves was validated with a test by lack of fitting and for the Anderson Darling normality test, using the software MINITAB in both cases. iv. The sensibility factor (F s ) for each energy corresponds to the slope of the CC, v. The F s for the two 192 Ir sources used are interpolated: one for a Micro Selectron source and the other one a Vari Source source. Finally, a couple of capsules were sent to two hospitals that have the HDR Brachytherapy with sources of 192

  2. Thermoluminescence characterisation of chemical vapour deposited diamond films

    CERN Document Server

    Mazzocchi, S; Bucciolini, M; Cuttone, G; Pini, S; Sabini, M G; Sciortino, S

    2002-01-01

    The thermoluminescence (TL) characteristics of a set of six chemical vapour deposited diamond films have been studied with regard to their use as off-line dosimeters in radiotherapy. The structural characterisation has been performed by means of Raman spectroscopy. Their TL responses have been tested with radiotherapy beams ( sup 6 sup 0 Co photons, photons and electrons from a linear accelerator (Linac), 26 MeV protons from a TANDEM accelerator) in the dose range 0.1-7 Gy. The dosimetric characterisation has yielded a very good reproducibility, a very low dependence of the TL response on the type of particle and independence of the radiation energy. The TL signal is not influenced by the dose rate and exhibits a very low thermal fading. Moreover, the sensitivity of the diamond samples compares favourably with that of standard TLD100 dosimeters.

  3. 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

  4. Electret dosemeter for beta radiation

    International Nuclear Information System (INIS)

    Campos, L.L.; Caldas, L.V.E.; Mascarenhas, S.

    The response characteristics of an electret dosemeter for beta radiation are studied. Experiments were performed using different geometries and walls, and it was verified for which geometry the dosemeter sensitivity is greater. Sources of 90 Sr - 90 Y, 204 Tl and 85 Kr were used in the experiments. (I.C.R.) [pt

  5. 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.)

  6. Testing the direct ion storage dosemeter for personal dosimetry in a nuclear research centre and a hospital.

    Science.gov (United States)

    Vanhavere, F; Covens, P

    2010-03-01

    The direct ion storage (DIS) dosemeter can have some clear advantages in personal dosimetry. Before introducing the DIS into practice in the dosimetry service, a series of tests was performed on the linearity, angular and energy dependence, temperature influences and hard resets. After that, for several months, the DIS dosemeters were worn in parallel with the legal dosemeters (thermoluminescent badge) in a nuclear research centre and in several departments of a university hospital. The conclusions are that the DIS has good characteristics to be used as legal personal dosemeter, and that the comparison with the TLD badge is good. Only in interventional radiology and cardiology fields the DIS gives significant lower values than the TLD badge.

  7. Use of digital dosemeters for supporting staff radiation safety in paediatric interventional radiology suites.

    Science.gov (United States)

    McNeil, Sarah M; Lai, Priscilla; Connolly, Bairbre L; Gordon, Christopher L

    2013-12-01

    Modern-day interventional radiology (IR) procedures impart a wide range of occupational radiation doses to team members. Unlike thermoluminescent badges, digital dosemeters provide real-time dose readings, making them ideal for identifying different components during IR procedures, which influence staff radiation safety. This study focused solely on paediatric IR (PIR) cases. Digital dosemeters measured the impact of imaging modality, shielding, patient and operator specific factors, on the radiation dose received during various simulated and real live PIR procedures. They recorded potential dose reductions of 10- to 100-fold to each staff member with appropriate use of shielding, choice of imaging method, staff position in the room and complex interplay of other factors. The digital dosemeters were well tolerated by staff. Results highlight some unique radiation safety challenges in PIR that arise from dose increases with magnification use and close proximity of staff to the X-ray beam.

  8. Use of digital dosemeters for supporting staff radiation safety in paediatric interventional radiology suites

    International Nuclear Information System (INIS)

    McNeil, S. M.; Lai, P.; Connolly, B. L.; Gordon, C. L.

    2013-01-01

    Modern-day interventional radiology (IR) procedures impart a wide range of occupational radiation doses to team members. Unlike thermoluminescent badges, digital dosemeters provide real-time dose readings, making them ideal for identifying different components during IR procedures, which influence staff radiation safety. This study focused solely on paediatric IR (PIR) cases. Digital dosemeters measured the impact of imaging modality, shielding, patient and operator specific factors, on the radiation dose received during various simulated and real live PIR procedures. They recorded potential dose reductions of 10-to 100-fold to each staff member with appropriate use of shielding, choice of imaging method, staff position in the room and complex interplay of other factors. The digital dosemeters were well tolerated by staff. Results highlight some unique radiation safety challenges in PIR that arise from dose increases with magnification use and close proximity of staff to the X-ray beam. (authors)

  9. Physical and Radiation Characterizations on New Thermoluminescence Dosemeter (TLD) Material

    International Nuclear Information System (INIS)

    Wan Saffiey Wan Abdullah; Nadira Kamarudin; Megat Harun Al Rashid; Mohd Taufik Dolah; Ishak Mansor; Hafzaliza Erny Zainal Abidin; Nurazila Mat Zali; Norlina Ab Aziz; Nurhaslinda Ee Abdullah

    2009-01-01

    Full text: A new TLD material for ionizing radiation measurement has been developed in Malaysian Nuclear Agency by using LiF and Mg as dopant. Wet precipitation techniques were used to produce and doped the LiF powder with 0.3 mol % of Mg. Physical characterization have been done by using various techniques. XRD was used to determine the crystallinity of the powder produce. The micrograph of the green and sintered powder were studied using SEM while the size of the powder produced were monitored using Particle Size Analyzer. Part of powder was pelleted to chips by using special mold and hydraulic pressing machine. The powder and chips were then irradiated to study the radiation characterization of the new TLD material produced. It is found that the developed material fulfill the characteristic of standard dosimeter with reproducibility and linearity better than 5% and sensitivity is more than 2 times compared to commercial product. (author)

  10. 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)

  11. Characterization of TLD-100 in powders for dosimetric quality control of {sup 192} Ir sources used in brachytherapy of high dose rate; Caracterizacion de TLD-100 en polvo para control de calidad dosimetrico de fuentes de Ir{sup 192} usadas en braquiterapia de alta tasa de dosis

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza C, S.P

    2007-07-01

    The Secondary Standard Dosimetric at the National Institute of Nuclear Research (ININ) calibrated a lot of powdered TLD-100 (LiF:Mg,Ti) in terms of absorbed dose to water D{sub w} for the energy of: {sup 60}Co, {sup 137C}s, X rays of 250 and 50 kVp. Later on, it is carried out an interpolation of the calibration for the energy of the {sup 192}Ir. This calibration is part of a dosimetric quality control program, to solve the problems of traceability for the measurements carried out by the users of {sup 192}Ir sources employed in the treatments of High Dose Rate Brachytherapy (HDR) at the Mexican Republic. The calibrations of the radiation beams are made with the following protocols: IAEA TRS-398 for the {sup 60}Co for D{sub w}, using a secondary standard ionization chamber PTW N30013 calibrated in D{sub w} by the National Research Council (NRC, Canada). AAPM TG-43 for D{sub w} in terms of the strength kerma Sk, calibrating this last one quantity for the {sup 137}Cs radioactive source, with a well chamber HDR 1000 PLUS traceable to the University of Wisconsin (US). AAPM TG-61 for X ray of 250 and 50 kVp for D{sub w} start to Ka using field standard a Farmer chamber PTW 30001 traceable to K for the Central Laboratory of Electric Industries (CLEI, France). The calibration curves (CC) they built for the response of the powder TLD: R{sub TLD} vs D{sub w}: For the energy of {sup 60}Co, {sup 137}Cs, X rays of 250 and 50 kVp. Fitting them with the least square method weighed by means of a polynomial of second grade that corrects the supra linearity of the response. iii. Each one of the curves was validated with a test by lack of fitting and for the Anderson Darling normality test, using the software MINITAB in both cases. iv. The sensibility factor (F{sub s}) for each energy corresponds to the slope of the CC, v. The F{sub s} for the two {sup 192}Ir sources used are interpolated: one for a Micro Selectron source and the other one a Vari Source source. Finally, a couple of

  12. Energy dependence of thermoluminescent response of CaSO{sub 4}:Dy, LiF:Mg and micro LiF:Mg,Ti in clinical beams of electrons by using different simulator objects; Dependencia energetica da resposta TL de dosimetros de CaSO{sub 4}:Dy, LiF:Mg e microLiF:Mg,Ti em feixes clinicos de eletrons utilizando diferentes objetos simuladores

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, Amanda; Campos, Leticia Lucente, E-mail: abravin@ipen.b, E-mail: rsakuraba@einstein.b, E-mail: lcrodri@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Sakuraba, Roberto K.; Cruz, Jose Carlos da, E-mail: rsakuraba@einstein.b, E-mail: josecarlosc@einstein.b [Hospital Israelita Albert Einstein (HIAE), Sao Paulo, SP (Brazil)

    2011-10-26

    Yet not so widely applied in radiotherapy, the calcium sulfate doped with dysprosium (CaSO{sub 4}:Dy) is used in radioprotection and studies has been demonstrated its great potential for the dosimetry in radiotherapy. This work evaluates the energy dependence of the thermoluminescent answer of the CaSO{sub 4}:D, LiF:Mg,Ti (TLD-100) and micro LiF:Mg,Ti in clinical beams of electrons by using water simulators, PMMA and solid water

  13. 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)

  14. New ISO standard - personnel photographic film dosemeters

    International Nuclear Information System (INIS)

    Brabec, D.

    1980-01-01

    The ISO Standard 1757 ''Personnel Photographic Film Dosemeters'', issued in June 1980, is briefly described. UVVVR's own dosemeter developed for use in the national film dosimetry service in Czechoslovakia is evaluated in relation to this ISO Standard. (author)

  15. The contribution of Teflon to the thermoluminescent signal

    International Nuclear Information System (INIS)

    German, U.; Weinstein, M.; Ben-Shachar; Pelled, O.

    1997-01-01

    In the thermoluminescent method, we are measuring the light emitted by the phosphor (called TL output), irradiated previously by ionizing radiation. There are several other effects, which can cause emission of light similar to the TL output, which can affect the results of personnel and environmental dosimetry, especially for low doses. It is described several such effects, as illumination of lithium fluoride thermoluminescent dosimeters, particularly with ultraviolet wavelengths. It was presented that the results of the glow curve of LiF:Mg,Ti chips, after exposure to different non-ionizing radiation (u.v., microwave, electric sparks). It has reviewed the reports of light induced signals in LiF ( I > 380 nm). These effects cause dosimeters to emit TL similar to that caused by exposure to ionizing These effects cause dosimeters to emit TL similar to that caused by exposure to ionizing radiation.A signal is received when heating teflon sheets, which contributes to the TL signal. It was pointed out that the light induced TL emission from the teflon has a glow peak 120 degree C. The purpose of the present work was to perform a quantitative evaluation of the glow contributed by the teflon used in the TLD cards employed by us Harshaw - TLD 100 for different storage conditions. (authors)

  16. Study of some characteristic dosimetric of the LIF:Mg, You (JR1152C) for their employment as environmental dosemeter

    International Nuclear Information System (INIS)

    Molina Perez, D.; Diaz Bernal, E.; Prendes Alonso, M.

    1998-01-01

    As the interest grows in knowing the effects on the health of the drops dose of natural or artificial radiation, it is made but necessary a system dosimetric able to measure those dose levels accurately. P but of twenty years the dosemeters thermoluminescent (TL) they have constituted a simple and beautiful method for such mensurations. In the work the rehearsals of homogeneity, reproducibility, line lay, detection threshold, auto irradiation, residual, fading and angular dependence are described. The results demonstrate that the dosemeter satisfies the main requirements to be an employee in the environmental monitoring

  17. Response of electret dosemeter to slow neutrons

    International Nuclear Information System (INIS)

    Ghilardi, A.J.P.; Pela, C.A.; Zimmerman, R.L.

    1987-01-01

    The response of electret dosemeter to slow neutrons exposure is cited, mentioning the preparation and the irradiation of dosemeter with Am-Be source. Some theory considerations about the response of electret dosemeter to slow and fast neutrons are also presented. (C.G.C.) [pt

  18. Effect of the temperature and relative humidity in dosemeters used for personnel monitoring

    International Nuclear Information System (INIS)

    Antonio Filho, J.

    1982-12-01

    The systematics of the combined effect of temperature and humidity on photographic dosimeters of the type Agfa-Gevaert, Kodak type II, III and the thermoluminescent dosimeters LiF:Mg,Ti (TLD-100, Harshaw), D-CaSO 4 :Dy-0,4 (Teledyne), e CaSO 4 :Dy+NaCl (IPEN), used in personal monitoring in Brazil was investigated, in the temperature range of 20 0 C to 50 0 C and relative humidity of 65% to 95%, in order to determine the best manner of utilization of these detectors in Brazilian climatic conditions. The dosimeters were studied in different forms of packing-sheet such as aluminezed paper and polyethylene. For the determination of the systematics, the dosimeters were irradiated in three conditions: before, during and after of storage in climatic chambers to a maximum period of 60 days. It was found that the dosimetric filmes and thermoluminescent dosimeter CaSO 4 :Dy+NaCl without protection, presented a high dependence to temperature and humidity, and when protected presented good results. Therefore, the best manner of utilization of these monitors in environments with relative humidity and temperature greater them 75% and 30 0 C respectively, is achieved with the protection of aluminized paper. The LiF:Mg,Ti and D+CaSO 4 :Dy-0,4 dosimeters can be utilized in their original form because they presented low dependence with humidity and temperature in the range studied. (Author) [pt

  19. 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

  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. Thermoluminescent dosimeters for exposure assessment in gamma or x radiation fields with unknown spectral distribution

    International Nuclear Information System (INIS)

    Da Rosa, L.A.R.; Nette, H.P.

    1988-01-01

    The determination of the effective energy of a radiation field using the energy dependence of the response ratio of two dosimeters with different energy dependences is called the Tandem Method. Having in view the choice of the best pair of dosimeters to be used, the energy response characteristics of LiF:Mg, Ti; CaSO 4 :Dy; CaF 2 :Dy and CaF 2 Mn thermoluminescent (TL) dosimeters were studied. Two different physical forms of TL dosimeters were investigated: hot pressed chips and Teflon disc dosimeters. The calibration factors were obtained for the energy of 60 Co γ rays and their energy dependence, normalized to 60 Co γ-radiation, was determined using spectral width as a parameter. Tandem systems formed by all LT dosimeters evaluated were compared. It was concluded that the Tandem D-CaSO 4 :Dy-0.4/LiF:Mg, Ti(TLD-100) determines the effective energy with a maximum uncertainty of only 10 keV and permits the assessment of the energy correction factor for the TLD-100 with a precision of better than 1.7% for the spectral distribution studied in the effective energy range from 30 to 100 keV. (author)

  2. 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)

  3. Comparative measurements of external radiation exposure using mobile phones, dental ceramic, household salt and conventional personal dosemeters

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2015-01-01

    Because retrospective dosimetry utilises commonly occurring materials and objects, it is particularly useful in cases of large-scale radiation accidents or malevolent acts with radioactive materials where casualties are inflicted on the general public and first emergency responders. The aim of this study was to investigate whether retrospective dosemeters can provide dose estimates with comparable accuracy like conventional personal dosemeters. Using an external source of radiation 137 Cs and an anthropomorphic phantom, we simulated serious irradiation of a human body in anterior-posterior and rotational geometries. Retrospective luminescence dosimetry objects, such as mobile phones, dental ceramic and household salt, and conventional personal dosemeters (thermoluminescent and electronic) were fixed to the anthropomorphic phantom. The doses obtained were compared with specific reference values. In most cases, relative deviations between the measured doses and the reference values did not exceed 20%. As the retrospective and conventional dosemeters show no significant differences in laboratory conditions, the retrospective luminescence dosimetry objects represent a very promising tool if handled properly. - Highlights: • A serious external exposure of human body was simulated. • Doses were measured using both retrospective and conventional dosemeters. • Utilised retrospective dosimetry materials were alumina resistors from mobile phones, household salt and dental ceramic. • Doses obtained were compared with reference values. • Both retrospective and conventional dosemeters gave similar results

  4. Thermoluminescence and Thermoluminescent Dosimetry, v. 3

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, Y.S.

    1984-01-01

    This work is a comprehensive review and guide to the fields of thermoluminescence and thermoluminescent dosimetry. Three up-to-date volumes contain useful tables, illustrations, formulas and references to aid researchers in radiation and nuclear science, dosimetry and solid state physics. Volume III focuses on clinical and archeological-geological applications of TLD. Detailed technical information on TL instrumentation is also included.

  5. Gamma dose estimation with the thermoluminescence method

    International Nuclear Information System (INIS)

    Kumamoto, Yoshikazu

    1994-01-01

    Absorbed dose in radiation accidents can be estimated with the aid of materials which have the ability of dose recording and were exposed during the accidents. Quartz in bricks and tiles used to construct the buildings has the thermoluminescent properties. These materials exposed to radiations emit light when heated. Quartz and ruby have been used for the estimation of dose. The requirements for such dosemeters include; (1)the high kiln temperature at which all thermoluminescent energies accrued from natural radiations are erased. (2)the negligible fading of thermoluminescent energies after the exposure to radiations. (3)the determination of dose from natural radiations after the making of the matcrials. (4)the geometry of the place at which materials are collected. Bricks or tiles are crushed in the motar, sieved into sizes, washed with HF, HCl, alchol, aceton and water, and given with a known calibration dose. The pre-dose method and high-temperature method are used. In the former, glow curves with and without calibration dose are recorded. In the latter, glow peaks at 110degC with and without calibration dose are recorded after the heating of quartz up to 500degC. In this report, the method of the sample preparation, the measurement procedures and the results of dose estimation in the atomic bombing, iridium-192 and Chernobyl accident are described. (author)

  6. Determination of X-ray effective energy using CaF2:Mn and LiF:Mg,Ti thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Vekic, B.; Miljanic, S.; Martincic, R.

    1998-01-01

    Using two dosemeters with different energy dependencies makes it possible to determine the effective energy of the incident radiation. The results give evidence that such a pair of thermoluminescent dosemeters can be used for the determination of the effective energy of x-ray beams within the energy range of 10 to 125 keV and for the determination of the dose absorbed in air. (M.D.)

  7. Evaluation of the directional dose equivalent H,(0.07) for ring dosemeters

    International Nuclear Information System (INIS)

    Alvarez R, J.T.; Tovar M, V.M.

    2006-01-01

    The personnel dosimetry laboratory (LDP) of the Metrology department received an user's of radiation beta application that incidentally had irradiated 14 couples of ring dosemeters for extremities of the type TLD-100 given by the LDP. This sample of 14 couples of rings tentatively it was irradiated in the months of July-August of the year 2004, and he requested in an expedite way the evaluation of the received dose equivalent. The LSCD builds two calibration curves in terms of the directional dose equivalent H'(0.07) using two sources patterns of 90 Sr- 90 Y for beta radiation: one of 74 MBq and another of 1850 MBq with traceability to the PTB. The first curve in the interval of 0 to 5 mSv, the second in the range of 5 to 50 mSv, taking into account effects by positioned of the rings in the phantom. Both calibration curves were validated by adjustment lack, symmetry of residuals and normality of the same ones. It is evaluated and analyzing the H'(0.007) for these 14 couples of rings using the Tukey test of media of a single road. It was found that the H , its could be classified in 4 groups, and that the probability that its has irradiated in a random way it was smaller to the level at α = 0.05. (Author)

  8. A new electret dosemeter for radiotherapy

    International Nuclear Information System (INIS)

    Rodrigues, L.N.

    1985-01-01

    The results obtained with a new plane electret dosemeter for use in Radiotherapy are presented. The working principle of the electret dosemeter in based on the use of the electret field the ion collecting field, similarly to an ionization chamber, and as charge integrator detector. The dosemeter had, initialy, a cylindrical geometry. The results attained with it's calibration curve concerning the sensitivity, the stability and the reproducibility lead to changes in the dosemeter geometry. A plane geometry dosemeter was built in order to increase the useful exposure range. The plane dosemeter sensitivity dependence was measured versus the electret charging conditions, the chamber volume and wall material (aluminium, brass and stainless steel). The stainless steel dosemeter showed the best results. This dosemeter has the following characteristics: sensitivity 10 -13 C/R, volume 0.20 cm 3 . Compared to the Baldwin-Farmer dosemeter, this results are fairly good. A multiple electret dosemeter was developed to monitor the uniformity of the radiation beam for a Cobalt Teletherapy unit. The intercomparasion with the Baldwin-Farmer unit presented a maximum variation of 3%. (author) [pt

  9. The development of a personal dosemeter for use by aircraft crew

    International Nuclear Information System (INIS)

    Stokes, R.P.; Talbot, L.

    2000-01-01

    This paper describes preliminary work to develop a cosmic-radiation dosemeter for use by military aircraft crew. The dosemeter is based on a combination of CR-39 etched-track detectors and TLD-700 thermoluminescent detectors. It is intended that the CR-39 be used to assess the neutron dose, while the TLD-700 is used to assess the photon and charged particle dose. The sensitivity of CR-39 to the neutron component of cosmic radiation was estimated by irradiating samples of the plastic at the CERN-CEC High Energy Reference Field Facility. This facility produced a radiation field with a neutron spectrum resembling that of the neutron component of cosmic radiation a typical airflight altitudes. The response of the CR-39 was linear over the range of doses studied (0.2-6.0 mSv) and there was no significant fading in the six-month period after irradiation. The TLD-700 component of the dosemeter was calibrated using 137 Cs gamma rays. The response of the TLD-700 was linear over the range of doses studied (0-1.1 mSv) with no significant fade in the six-month period after irradiation. It was concluded that a combination of CR-39 and TLD-700 detectors would provide an effective cosmic-radiation dosemeter for use by military aircraft crew. (author)

  10. Colour dosemeters for high level radiation dosimetry

    DEFF Research Database (Denmark)

    Schönbacher, H.; Coninckx, F.; Miller, A.

    1990-01-01

    Development work was undertaken in order to produce a visual dosemeter system for measurement of radiation levels around the present and future high energy particle accelerators. This dosemeter should exhibit radiation induced colours in the visible part of the spectrum leading to a visual dose i...... such as commercial irradiation facilities is envisaged. Calibration of the dosemeters was made with a Co-60 source up to 10(6) Gy....... radiation; and (2) a paint containing a base substance with a pigment. The paint dosemeter remained unaffected by irradiation up to 3 x 10(4) Gy while the film dosemeter showed a measurable colour change from 10(4) Gy to 5 x 10(5) Gy. Above 10(6) Gy the film dosemeter is destroyed by radiation. Samples...... of paint and film dosemeters were installed in the 450 GeV Super Proton Synchrotron (SPS) at CERN and irradiated during operation for more than two years. Within the useful range of the dosemeters, dose comparisons with other dosemeter types gave satisfactory results. Application in other fields...

  11. 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

  12. 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)

  13. Dose measurements using thermoluminescent dosimeters and DoseCal software at two paediatric hospitals in Rio de Janeiro

    Energy Technology Data Exchange (ETDEWEB)

    Mohamadain, K.E.M.; Azevedo, A.C.P.; Rosa, L.A.R. da E-mail: lrosa@ird.gov.br; Guebel, M.R.N.; Boechat, M.C.B

    2003-07-01

    A dosimetric survey in paediatric radiology is currently being carried out at the paediatric units of two large hospitals in Rio de Janeiro city: IPPMG (Instituto de Pediatria e Puericultura Martagao Gesteira, University Hospital of Federal University of Rio de Janeiro) and IFF (Instituto Fernandes Figueira, FIOCRUZ). Chest X-ray examination doses for AP, PA and LAT projections of paediatric patients have been obtained with thermoluminescent dosimeters (TLDs) and with use of a software package DoseCal. In IPPMG and IFF 100 patients have been evaluated with the use of the TLDs and another group of 100 patients with the DoseCal software. The aim of this work was to estimate the entrance skin dose (ESD) for frontal, back and lateral chest X-rays exposure of paediatric patients. For ESD evaluation, three different TL dosimeters have been used, namely LIF:Mg, Ti (TLD100), CaSO{sub 4}:Dy and LiF:Mg, Cu, P (TLD100H). The age intervals considered were 0-1, 1-5, 5-10 and 10-15 years. The results obtained with all dosimeters are similar, and it is in good agreement with the DoseCal software, especially for AP and PA projections. However, some larger discrepancies are presented for the LAT projection.

  14. 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

  15. 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)

  16. Alumina as a thermoluminescent material for personnel dosimetry

    International Nuclear Information System (INIS)

    Beinsteiner, J.

    1980-06-01

    In this paper the possible use of aluminium for dosimeters is investigated. The thermoluminescence recovery should be enhanced by different forms of doping and the form of the dosimeter should give reproductable results. Doping was done by coprecipitation of the additive with an Al salt from aqueous solutions and then converting to the oxides by heating. Doping with 850 ppm Tb 2 O 3 gives a 50 fold enhancement of the sensitivity. The emission of light is in the blue range. The use of PTFE for matrix material is strongly restricted because PTFE absorbes too much of the blue light. Sintering in vacuum or in hydrogen converts Tb 4 O 7 into Tb 2 O 3 and the reaction Tb(III)-radiation, heat-Tb(II) activates the luminescence. Tablets of these material produced by sintering in hydrogen with peaks at 125 and 72 0 C are 13 times as sensitive as LiF (TLD-100) and are linear in the range till 5000R. Fading in one month is 20% but loss of information is 13% after the first day. An apparatus was built which allows a semiautomatical evaluation of 50 dosimeters. (P.W.)

  17. Theory of thermoluminescence gamma dose response: The unified interaction model

    Science.gov (United States)

    Horowitz, Y. S.

    2001-09-01

    We describe the development of a comprehensive theory of thermoluminescence (TL) dose response, the unified interaction model (UNIM). The UNIM is based on both radiation absorption stage and recombination stage mechanisms and can describe dose response for heavy charged particles (in the framework of the extended track interaction model - ETIM) as well as for isotropically ionising gamma rays and electrons (in the framework of the TC/LC geminate recombination model) in a unified and self-consistent conceptual and mathematical formalism. A theory of optical absorption dose response is also incorporated in the UNIM to describe the radiation absorption stage. The UNIM is applied to the dose response supralinearity characteristics of LiF:Mg,Ti and is especially and uniquely successful in explaining the ionisation density dependence of the supralinearity of composite peak 5 in TLD-100. The UNIM is demonstrated to be capable of explaining either qualitatively or quantitatively all of the major features of TL dose response with many of the variable parameters of the model strongly constrained by ancilliary optical absorption and sensitisation measurements.

  18. Response of electret dosemeter to slow neutrons

    International Nuclear Information System (INIS)

    Ghilardi, A.J.P.; Pela, C.A.; Zimmerman, R.L.

    1987-01-01

    The response of the electret dosemeter to exposition of slow neutrons is studied. Different external coatings are used on the dosemeter (polyethylene, alminium, polyethylene + boron, aluminium + boron) and exposure curves (with and without water) are compared. (M.A.C.) [pt

  19. Charge stabilization on the electret dosemeter

    International Nuclear Information System (INIS)

    Pela, C.A.; Guilardi, A.J.P.; Ghilardi Netto, T.

    1987-01-01

    The charge stabilization and how eliminate the humidity effects in electret dosemeter are shown. The charge measure along of time, changing with the humidity is observed. The fabrication of dryness chamber with silica gel for a more adequate use of dosemeter in differents physical conditions of environment is also cited. (C.G.C.) [pt

  20. Development trends of radiophotoluminescent glass dosemeter

    International Nuclear Information System (INIS)

    Ikegami, T.

    2004-01-01

    RPL glass dosemeter has been recently recognized to have a good performance as accumulation dosemeter and has been routinely used for personal dosimetry and environmental radiation monitoring. Furthermore, its applicable field is being extending to medical radiation measurement. The history of RPL glass dosemeter is very long. It was born in USA in 1950s and after that it was improved in Japan. And it was used as personal dosemeter in 1970s. But, in those days, RPL glass dosemeter was not suitable to low dose measurement due to some handling problems. So, its use had been reduced gradually. The author has broken through any past problems, by mainly realizing the pulsed UV excitation method. In this paper, the development history, principle and features, and the development good results of the pulsed UV excitation method are summarized, including the introduction of recent RPL glass dosimetry products. (author)

  1. Fast neutron sensitivity of polymer dosemeters

    International Nuclear Information System (INIS)

    Harper, M.W.; Pearson, D.W.; Moran, P.R.

    1975-01-01

    The responses of polymer thermocurrent dosemeters to fission spectrum and 14 MeV neutrons were measured. The dosemeters are in the form of disks 1 cm diam by 0.5 mm thick. Relative to Cobalt 60 gamma responses, teflon PTFE dosemeters show a 6 percent response to 14 MeV neutrons and a 5 percent response to fission neutrons on a tissue rad basis. Polymethylpentene dosemeters show a 49 percent response to 14 MeV neutrons and a 40 percent response to fission neutrons on a tissue rad basis when provided with adequate recoil proton buildup. The sensitivity of these dosemeters is limited to neutron doses greater than 10 rads by spurious background currents

  2. Colour dosemeters for high level radiation dosimetry

    DEFF Research Database (Denmark)

    Schönbacher, H.; Coninckx, F.; Miller, A.

    1990-01-01

    Development work was undertaken in order to produce a visual dosemeter system for measurement of radiation levels around the present and future high energy particle accelerators. This dosemeter should exhibit radiation induced colours in the visible part of the spectrum leading to a visual dose...... interpretation or a dose measurement with a simple instrument such as a portable reflecting densitometer in the range of 10(3) to 10(6) Gy. Two projects were investigated: (1) a thin plastic film with a self adhesive tape containing a radiochromic dye which induces a colour change when exposed to ionising...... radiation; and (2) a paint containing a base substance with a pigment. The paint dosemeter remained unaffected by irradiation up to 3 x 10(4) Gy while the film dosemeter showed a measurable colour change from 10(4) Gy to 5 x 10(5) Gy. Above 10(6) Gy the film dosemeter is destroyed by radiation. Samples...

  3. Problems at the Development of personal Beta-particle dosemeters-Beta Particle dosemeters-

    International Nuclear Information System (INIS)

    Helmstadter, K.; Ambrosi, P.

    2002-01-01

    Workplaces at which beta radiation might significantly contribute to the doses to the extremities are increasingly found in radiation therapy, radiation source production and nuclear plants. for the measurement of the individual beta-particle dose, personal dosemeters for fingers, arms and legs are needed. Intercomparison measurements organised from 1996 by the PTB have shown that some dosemeter types based on TLD are suitable for this purpose and can be used as legal dosemeters for both photon and beta radiation. Also, some electronic personal photon dosemeters are investigated in beta radiation fields. it turned out that a few types are also sensitive to beta radiation and measure the personal dose equivalent rate to the skin with a low energy dependence. Only their wearing position is by far not optimal foe extremity dosimetry because they are worn on the chest. Advantages and disadvantages are discussed. The characterisation of workplaces is carried out by measuring dose profiles using area dosemeters. Investigations performed with several commercial types of these dosemeters furnish information about the selection of the suitable measuring device and its correct practical use. the development of improved dosemeters has to towards smaller detectors and higher sensitivity. Personal dosemeters have to be robust and acceptable to the user, which generally is not achieved for beta extremity dosemeters. It is an additional problem that even such dosemeters cannot always be worn in the appropriate place. (Author)

  4. Production of LiF films for dosimetric thermoluminescence application

    International Nuclear Information System (INIS)

    Mauricio, Claudia Lucia de Pinho

    2000-12-01

    This work studies the LiF monolayer and multilayer polycrystalline film's dosimetric properties. The films were produced by electron beam evaporation technique in aluminium and stainless steel substrates maintained at several temperatures. As dosimetric variable, the intensity of the thermoluminescent (TL) glow curve of the films was used. effects of the substrate type and temperature; of the addition of layers of Mg F 2 NaF and Cu F 2 to the LiF films; and of thermal treatments in the TL response of the produced films were studied. The microstructural characterization of the films was accomplished through measures of scanning electronic microscopy and grazing incidence X-rays diffraction analysis. The dosimetric characterization was made of gamma radiation exposure in a 60 Co source, with kerma from 0,1 to 500 Gy. Studies of reproducibility, homogeneity, stability and other environmental effects were also made. LiF and Cu F 2 : LiF; Mg F 2 films were the only ones that presented mechanical stability and reproducibility of the TL emission. There is a strong indication of some correlation between the residual tension fields inside the films and the intensity of its TL emission peaks. LiF monolayer films present supralinear behaviour from 0,2 to 100 Gy. These films present a main TL glow peak around 150 deg C, whose half-time is about 30 days. Its volumetric sensitivity can reach about 60 times that of LiF powder and about 0,25 that of TLD100 (LiF:Mg, Ti commercial dosimeter from Harshaw Chemical Co.) The homogeneity and reproducibility inside a same film batch is better than 12% for 95% confidence level. Cu F 2 : LiF: Mg F 2 films present linear behaviour from 3 to 500 Gy and its main TL glow peak around 200 deg C did not present any fading for a a period of 30 days, in laboratory conditions. This glow peak is characteristic of the Mg doping of LiF, which confirms the diffusion of Mg ions from the Mg F 2 layer to the LiF layer. The TL volumetric sensitivity of these

  5. Application of radiophotoluminescence dosemeters for environmental monitoring

    International Nuclear Information System (INIS)

    Mihara, A.; Tamura, T.; Mochizuki, T.; Numakunai, T.; Yoshida, Y.; Ohi, Y.

    1993-01-01

    Feasibility study has been made on the radiofluorescence glass (RPL) dosemeters for environmental radiation monitoring. Main items in the laboratory tests are batch uniformities of pre-dose and sensitivity, build-up characteristics of RPL intensity, energy and angular responses, stabilities for RPL reading, anneal cycling and climatic conditional changes. We have determined self-irradiation dose and cosmic ray contribution. Radiation monitoring field test for the RPL dosemeters has been conducted in comparison with the present TLD systems. A procedure manual for the environmental monitoring by the use of RPL dosemeters is in preparation

  6. Passive neutron dosemeter with activation detector

    Energy Technology Data Exchange (ETDEWEB)

    Valero L, C.; Banuelos F, A.; Guzman G, K. A.; Borja H, C. G.; Hernandez D, V. M.; Vega C, H. R., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-10-15

    A passive neutron dosemeter with {sup 197}Au activation detector has been developed. The area dosemeter was made as a 20.5 {phi} x 20.5 cm{sup 2} polyethylene moderator, with a polyethylene pug where a {sup 197}Au foil can be located either parallel or perpendicular to moderator axis. Using Monte Carlo methods, with the MCNP5 code. With the fluence response and the fluence-to-equivalent dose conversion coefficients from ICRP-74, responses to H*(10) were also calculated, these were compared against responses of commercially available neutron area monitors and dosemeters. (Author)

  7. 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

  8. 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

  9. Study about the feasibility of using an electret dosemeter as a personal dosemeter

    International Nuclear Information System (INIS)

    Leitao, I.P.

    1983-01-01

    A feasibility study of the electret dosemeters as a personnel dosemeter was carried out. Preliminary tests were applied, in order to assess the dosemeter response to radiation, linearity, stability, reproductibility, direcional dependence and energy dependence in energy range from 33 to 1250 KeV. In general the results are in agreement with the recommendations of the Commision of the European Communities (CEC) for the use of this device as a personnel dosemeter with the exception of the energy dependence and the stability at medium term. (Author) [pt

  10. 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)

  11. Dosimetric study of thermoluminescent detectors in clinical photon beams using liquid water and PMMA phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, Luciana C., E-mail: lmatsushima@ipen.br [Gerencia de Metrologia das Radiacoes (GMR) - Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Av. Prof. Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-000, Sao Paulo, SP (Brazil); Veneziani, Glauco R. [Gerencia de Metrologia das Radiacoes (GMR) - Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Av. Prof. Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-000, Sao Paulo, SP (Brazil); Sakuraba, Roberto K. [Gerencia de Metrologia das Radiacoes (GMR) - Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Av. Prof. Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-000, Sao Paulo, SP (Brazil); Sociedade Beneficente Israelita Brasileira - Hospital Albert Einstein (HAE), Avenida Albert Einstein, 665, Morumbi, CEP: 05652-000, Sao Paulo, SP (Brazil); Cruz, Jose C. da [Sociedade Beneficente Israelita Brasileira - Hospital Albert Einstein (HAE), Avenida Albert Einstein, 665, Morumbi, CEP: 05652-000, Sao Paulo, SP (Brazil)

    2012-07-15

    The purpose of this study was the dosimetric evaluation of thermoluminescent detectors of calcium sulphate doped with dysprosium (CaSO{sub 4}:Dy) produced by IPEN compared to the TL response of lithium fluoride doped with magnesium and titanium (LiF:Mg,Ti) dosimeters and microdosimeters produced by Harshaw Chemical Company to clinical photon beams dosimetry (6 and 15 MV) using liquid water and PMMA phantoms. - Highlights: Black-Right-Pointing-Pointer Dosimetric study of thermoluminescent detectors of CaSO{sub 4}:Dy, LiF:Mg,Ti and {mu}LiF:Mg,Ti. Black-Right-Pointing-Pointer Clinical (6 and 15 MV) photon beams dosimetry using liquid water and PMMA phantom. Black-Right-Pointing-Pointer Linear behavior to the dose range (0.1 to 5 Gy). Black-Right-Pointing-Pointer TL response reproducibility better than {+-}4.34%. Black-Right-Pointing-Pointer CaSO{sub 4}:Dy represent a cheaper alternative to the TLD-100.

  12. Synthesis and thermoluminescence properties of rare earth-doped NaMgBO3 phosphor.

    Science.gov (United States)

    Khan, Z S; Ingale, N B; Omanwar, S K

    2016-05-01

    Rare earth (Dy(3+) and Sm(3+))-doped sodium magnesium borate (NaMgBO3) is synthesized by solution combustion synthesis method keeping their thermoluminescence properties in mind. The reaction produced very stable crystalline NaMgBO3:RE (RE = Dy(3+), Sm(3+)) phosphors. The phosphors are exposed to (60)Co gamma-ray radiations dose of varying rate from 5 to 25 Gy, and their TL characteristics with kinetic parameters are studied. NaMgBO3:Dy(3+) phosphor shows two peaks for lower doping concentration of Dy(3+) while it reduced to single peak for the higher concentrations of activator Dy(3+). NaMgBO3:Dy(3+) shows the major glow peak around 200 °C while NaMgBO3:Sm(3+) phosphors show two well-separated glow peaks at 200 and 332 °C respectively. The thermoluminescence intensity of these phosphors was compare with the commercially available TLD-100 (Harshaw) phosphor. The TL responses for gamma-ray radiations dose were found to be linear from 5 to 25 Gy for both phosphors while the fading in each case is calculated for the tenure of 45 days.

  13. 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)

  14. The need for comparison of diagnostic dosemeters

    International Nuclear Information System (INIS)

    Kramer, H.M.

    1989-01-01

    One precondition for successfully implementing quality control in diagnostic radiology is that the measuring instruments used are of adequate quality. Among the measuring instruments used for quality control, dosemeters play a predominant role. Therefore it is essential to know the performance characteristics of a suitable dosemeter and to have information on the uncertainties and measurement errors found during acceptance testing. An outline will be given of the requirements on the accuracy of dosemeters. Such requirements have to address the task of the dosemeter and also take into account their technical feasibility. In order to gather information on the performance characteristics of field instruments, a programme for a European intercomparison has been developed which was carried out in 1988. The programme, together with its underlying ideas and its objectives, is presented in this paper. (author)

  15. Self-indicating radiation alert dosemeter (SIRAD)

    International Nuclear Information System (INIS)

    Riel, G. K.; Winters, P.; Patel, G.; Patel, P.

    2006-01-01

    In an event of a nuclear or dirty bomb explosion and a radiological accident, there is a need for self-indicating instant radiation dosemeter for monitoring radiation exposure. The self-indicating instant radiation alert dosemeter (SIRAD) is a credit card size radiation dosemeter for monitoring ionising radiation from a few hundredths of a Gray to a few Gray. It is always active and is ready to use. It needs no battery. The dosemeter develops colour instantly upon exposure, and the colour intensifies with dose. It has a colour chart so that the dose on the active element may be read by matching its colour with the chart that is printed next to it on the card. However, in this work, the dose is measured by the optical density of the element. The dosemeter cannot be reset. The response changes by 3 y at room temperature. It contains no hazardous materials. The dosemeter would meet the requirements of instantly monitoring high dose in an event of a nuclear or dirty bomb explosion or a radiation accident. (authors)

  16. 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

  17. Measuring the absorbed dose in critical organs during low rate dose brachytherapy with {sup 137} Cs using thermoluminescent dosemeters; Medicion de la dosis absorbida en organos criticos durante braquiterapia de baja tasa de dosis con {sup 137} Cs usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Torres, A. [UAEM, Fac. de Medicina, 50180 Toluca, Estado de Mexico (Mexico); Gonzalez, P.R. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Furetta, C.; Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Andres, U.; Mendez, G. [Centro Estatal de Cancerologia de Tabasco, A. Gregorio Mendez No. 2838, Col. Atasta, 86100 Villahermosa, Tabasco (Mexico)

    2003-07-01

    Intracavitary Brachytherapy is one of the most used methods for the treatment of the cervical-uterine cancer. This treatment consists in the insertion of low rate dose {sup 137}Cs sources into the patient. The most used system for the treatment dose planning is that of Manchester. This planning is based on sources, which are considered fixed during the treatment. However, the experience has shown that, during the treatment, the sources could be displaced from its initial position, changing the dose from that previously prescribed. For this reason, it is necessary to make measurements of the absorbed dose to the surrounding organs (mainly bladder and rectum). This paper presents the results of measuring the absorbed dose using home-made LiF: Mg, Cu, P + Ptfe thermoluminescent dosimeters (TLD). Measurements were carried out in-vivo during 20 minutes at the beginning and at the end of the treatments. Results showed that the absorbed dose to the critical organs vary significantly due to the movement of the patient during the treatment. (Author)

  18. 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.)

  19. 128 slice computed tomography dose profile measurement using thermoluminescent dosimeter

    International Nuclear Information System (INIS)

    Salehhon, N; Hashim, S; Karim, M K A; Ang, W C; Musa, Y; Bahruddin, N A

    2017-01-01

    The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDI air ) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDI air increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDI air values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDI air value (13.585 mGy). The p -value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner. (paper)

  20. 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)

  1. Thermoluminescent Dosimetry: A Preliminary Study for microCT Applications

    International Nuclear Information System (INIS)

    Montano Garcia, C.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Brandan, M. E.; Ruiz-Trejo, C.

    2006-01-01

    Preliminary measurements for microCT dosimetry are reported in this work, using TLD-100 crystals (1x1x1 mm3) within a solid water phantom specially designed with approximate dimensions of a mouse. A dose dependence as a function of radial distance and position along the axis of the phantom was found. Because of the smaller doses used in this work we can say that it is feasible to perform dosimetry measurements with high accuracy using TLD-100 microcubes

  2. Thermoluminescent response of CaSO{sub 4}: Dy + PTFE to beta particles; Respuesta termoluminiscente de CaSO{sub 4}: Dy + PTFE a particulas beta

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre C, A.; Azorin N, J. [Colegio de Bachilleres No. 13, Xochimilco-Tepepan, 16000 Mexico D.F. (Mexico)

    2000-07-01

    In this work the results of studying the thermoluminescent properties of CaSO{sub 4}: Dy + PTFE are presented when it is irradiated with beta particles. The conclusion was the obtention of the Tl response curve in function of dose is that to desexcite the dosemeters at temperature 300 C during 30 minutes and after that were irradiated at different times in groups and to do the reading of dosemeter, it can be observed that a greater irradiation time major is the Tl response and this depends of the material has been used. (Author)

  3. 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)

  4. Calibrations of pocket dosemeters using a comparison method

    International Nuclear Information System (INIS)

    Somarriba V, I.

    1996-01-01

    This monograph is dedicated mainly to the calibration of pocket dosemeters. Various types of radiation sources used in hospitals and different radiation detectors with emphasis on ionization chambers are briefly presented. Calibration methods based on the use of a reference dosemeter were developed to calibrate all pocket dosemeters existing at the Radiation Physics and Metrology Laboratory. Some of these dosemeters were used in personnel dosimetry at hospitals. Moreover, a study was realized about factors that affect the measurements with pocket dosemeters in the long term, such as discharges due to cosmic radiation. A DBASE IV program was developed to store the information included in the hospital's registry

  5. 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)

  6. 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)

  7. A new extremity dosemeter for beta and gamma radiation

    International Nuclear Information System (INIS)

    Heinzelmann, M.; Pagenkamper, M.

    1988-01-01

    An extremity dosemeter developed at the Juelich Nuclear Research Centre is very well suited for the precise and energy-independent measurement of the skin dose generated by beta or gamma radiation. This is also confirmed by the results of this intercomparison programme. The dosemeter contains three TLDs of LiF in Teflon mounted behind a window of 0.9 mg/cm 2 . The great advantage of this dosemeter is three TLD's enabling statements about the radiation quality. However, the dosemeter has two disadvantages The dosemeter is complicated to manufacture. A very thin plastic foil of 0.9 mg/cm 2 must be attached to a support. This work is difficult and time-consuming and cannot be automated. The window in front of the TLD is not sturdy enough and is occasionally destroyed when the dosemeter is being worn. These two disadvantages prevent this extremity dosemeter from being used more frequently. For this reason, work was begun on developing a new extremity dosemeter without these two disadvantages. The great advantage of the previous dosemeter of obtaining statements about the type of radiation with the aid of readings from three TLD's was to be retained. The improved extremity dosemeter has a more sturdy and thicker window with a similar response as the previous dosemeter with a thinner window

  8. 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

  9. Datation par thermoluminescence

    Directory of Open Access Journals (Sweden)

    1976-01-01

    Full Text Available Depuis 1953, de nombreux chercheurs se sont intéressés à la datation par thermoluminescence de minéraux anciennement brûlés ou cuits. Dans ce travail, après avoir rappelé quelques principes physiques de la thermoluminescence, on présente cette méthode de datation en mettant l'accent sur le mécanisme thermoluminescent dans une poterie. Ainsi la dose d'irradiation reçue par le matériau étant proportionnelle au temps écoulé depuis le 'zéro archéologique', il est possible de déterminer 'la dose archéologique' et d'en déduire l'âge de l'échantillon après avoir calculé la dose d'irradiation annuelle. La réalisation pratique d'un tel ensemble de mesure est cependant très ardue. Dans un prochain article, E. A. Decamps et A. Roman montreront des résultats relatifs à la thermoluminescence d'échantillons de quartz naturels, purs et dopés et la mise au point d'une nouvelle méthode de datation. Desde 1953, muchos investigadores se han interesado en la datación por termoluminiscencia de minerales antiguamente quemados o cocidos. Dentro de este trabajo, luego de haber recordado algunos principios físicos de la termoluminiscencia, se presenta este método de datación poniendo mayor atención en el mecanismo termoluminescente en una vasija de metal o de barro. Siendo proporcional la dosis de irradiación recibida al tiempo transcurrido desde el 'cero arqueológico', es posible determinar 'la dosis arqueológica', y deducir la edad de la muestra luego de haber calculado la dosis de irradiación anual. La realización práctica de un trabajo de tal dimensión es sin embargo muy ardua. En un próximo artículo, E. A. Decamps y A. Román presentarán los resultados relativos a la termoluminiscencia de muestras de cuarzo naturales, puras y dopadas y la elaboración de un nuevo método de datación. Since 1953, a number of scientists have been concerned with the use of thermoluminescence for the dating of burned or fired minerals

  10. 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

  11. 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)

  12. Thermoluminescence of kaolinite

    OpenAIRE

    García-Guinea, Javier; Correcher, Virgilio; Valle Fuentes, Francisco José

    1998-01-01

    Natural kaolinite (size < 5 ¿m) shows strong thermoluminescence (TL) which could be linked with water loss (~ 120°C peak) and dehydroxylation changes (~ 300°C peak). After 100 min of dehydration at room temperature, kaolinite displays microcracks, isothermal luminescence emissions and the starting point of a desiccation plateau. These phenomena were tested through 34 X ray diffractograms measuring the area increase of the (001) peak each 3 min. The DTA-TG analyses of natural kaolinite and the...

  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. Absorbed dose measurements in mammography using Monte Carlo method and ZrO2+PTFE dosemeters

    International Nuclear Information System (INIS)

    Duran M, H. A.; Hernandez O, M.; Salas L, M. A.; Hernandez D, V. M.; Vega C, H. R.; Pinedo S, A.; Ventura M, J.; Chacon, F.; Rivera M, T.

    2009-10-01

    Mammography test is a central tool for breast cancer diagnostic. In addition, programs are conducted periodically to detect the asymptomatic women in certain age groups; these programs have shown a reduction on breast cancer mortality. Early detection of breast cancer is achieved through a mammography, which contrasts the glandular and adipose tissue with a probable calcification. The parameters used for mammography are based on the thickness and density of the breast, their values depend on the voltage, current, focal spot and anode-filter combination. To achieve an image clear and a minimum dose must be chosen appropriate irradiation conditions. Risk associated with mammography should not be ignored. This study was performed in the General Hospital No. 1 IMSS in Zacatecas. Was used a glucose phantom and measured air Kerma at the entrance of the breast that was calculated using Monte Carlo methods and ZrO 2 +PTFE thermoluminescent dosemeters, this calculation was completed with calculating the absorbed dose. (author)

  16. Photon beam audits for radiation therapy clinics: A pilot mailed dosemeter study in Turkey

    International Nuclear Information System (INIS)

    Yegingil, Z.; DeWerd, L. A.; Davis, S. D.; Hammer, C.; Kunugi, K.

    2012-01-01

    A thermoluminescent dosemeter (TLD) mailed dose audit programme was performed at five radiotherapy clinics in Turkey. The intercomparison was organised by the Univ. of Wisconsin Radiation Calibration Laboratory (UWRCL), which was responsible for the technical aspects of the study including reference irradiations, distribution, collection and evaluation. The purpose of these audits was to perform an independent dosimetry check of the radiation beams using TLDs sent by mail. Acrylic holders, each with five TLD chips inside and instructions for their irradiation to specified absorbed dose to water of 2 Gy, were mailed to all participating clinics. TLD irradiations were performed with a 6 MV linear accelerator and 60 Co photon beams. The deviations from the TL readings of UWRCL were calculated. Discrepancies inside the limits of ±5 % between the participant-stated dose, and the TLD-measured dose were considered acceptable. One out of 10 beams checked was outside this limit, with a difference of 5.8 %. (authors)

  17. 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

  18. Thermoluminescent characterization of thin films of aluminium oxide submitted to beta and gamma radiation

    International Nuclear Information System (INIS)

    Villagran, E.; Escobar A, L.; Camps, E.; Gonzalez, P.R.; Martinez A, L.

    2002-01-01

    By mean of the laser ablation technique, thin films of aluminium oxide have been deposited on kapton substrates. These films present thermoluminescent response (Tl) when they are exposed to beta and gamma radiation. The brilliance curves show two peaks between 112 C and 180 C. A dose-response relationship study was realized and the Tl kinetic parameters were determined using the computerized deconvolution of the brilliance curve (CGCD). The thin films of aluminium oxide have potential applications as ultra.thin radiation dosemeters. (Author)

  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. Measurement of staff doses in interventional procedures using LiF TL-detectors and a special diode dosemeter

    Energy Technology Data Exchange (ETDEWEB)

    Parviainen, T.; Toivonen, M.; Kosunen, A.; Karppinen, J. [Radiation and Nuclear Safety Authority, Helsinki (Finland); Ylitalo, A. [Satakunta Central Hospital, Division for Cardiology, Pori (Finland)

    2003-06-01

    Personal doses vary considerably among the operational staff in cardiac examination procedures and interventions. Correspondingly, the fluoroscopy time may vary from a few minutes to more than 1 hour. Large personal doses in the range of 35 - 41 mSv were registered to some interventional radiologists and cardiologists in 2001 in Finland. Measurement of doses per intervention from hands, shoulders and ankles (parts of the body outside the lead apron) are therefore of interest, but small and highly sensitive dosemeters have not been commonly available for reliable and practical measurements. Thermoluminescent detectors of LiF:MgCu,P are sensitive enough, but residual luminescence from previous uses of detectors and the dose collected from natural background radiation between preparation for use and readout may be significant sources of uncertainty. The company Unfors Instrumens AB (Billdal, Sweden) has designed a light weight diode dosemeter with long cables between detectors and the electronic part for simultaneous measurement of doses from various parts of the body. The aim of this work is to report doses of the operating staff per a cardiac examination or intervention and study the capabilities of the diode dosemeter in staff dose measurements. (orig.)

  1. 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)

  2. 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)

  3. Thermoluminescence dating (TL-dating): measurement and accuracy factors in archaeological dating of ceramic base materials

    International Nuclear Information System (INIS)

    Wan Saffiey Wan Abdullah

    2004-01-01

    Thermoluminescence dating is one of the known techniques that have been established in many laboratories across the region. This technique is capable of dating the archaeological ceramic base materials and provide an absolute measurement with an accuracy of ±15%. The study involves the dating of pottery from a historical site at Sungai Mas, Mukim Kota, Daerah Kuala Muda, Kedah. Pieces of broken pottery of archaeological sample excavated by the Museum Department and Antiquity (JMA) have been dated using the thermoluminescence detector (TLD) techniques at MINT laboratory. A TLD dosemeter of LiF chips is used for the measurement of background and sample dose measurement. The preparation of sample and the calibration techniques for the estimation of palaedose or dose presented in the sample since distant past is established. Results indicate that the samples are in the era of civilization from 200 BP to 1600 BP. Error factors associated in the measurement procedures were identified and discussed. (Author)

  4. 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

  5. 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)

  6. Principle and use of dosemeters; Principe et utilisation des dosimetres

    Energy Technology Data Exchange (ETDEWEB)

    Genet, S.; Ribaud, I.

    1997-12-31

    The institute of nuclear physics of Orsay is accepted by the Ministry of Labour to insure the surveillance of workers individual external exposure against the danger of ionizing radiations and to execute monitoring of radiation protection. The dosemeters studied in this report are the photographic film dosemeters ( for x rays, gamma rays and beta {sup -} rays), the trace detectors (fast neutrons) and the radio thermo luminescent dosemeters. For each type, the principle and how to use it are given. (N.C.).

  7. Evaluation of neutron doses received at different organs in radiotherapy treatments using the UAB PADC based dosemeters in an anthropomorphic phantom

    Energy Technology Data Exchange (ETDEWEB)

    Domingo, C., E-mail: carles.domingo@uab.ca [Grup de Fisica de les Radiacions, Departament de Fisica, Edifici C, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Garcia-Fuste, M.J.; Morales, E.; Amgarou, K.; Castelo, J. [Grup de Fisica de les Radiacions, Departament de Fisica, Edifici C, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Sanchez-Doblado, F. [Hospital Universitario Virgen Macarena, Servicio de Radiofisica, Sevilla (Spain); Departamento de Fisiologia Medica y Biofisica, Facultad de Medicina, Universidad de Sevilla (Spain)

    2009-10-15

    The NEUTOR project was set up to study radiotherapy patient exposures to the neutrons produced around the LINAC accelerator head by photon radiation above approx8 MeV. These neutrons may reach the patient directly, or they may interact with the surrounding materials until they become thermalised, scattering all over the treatment room and affecting the patient as well. A miniaturised version of the UAB PADC based neutron dosemeter is used, together with thermoluminescence Li-6/Li-7 pairs, in several positions inside an anthropomorphic female phantom to determine doses received by the patient at several organs or tissues. Irradiations were made at a 15 MV LINAC (Hospital Universitario Virgen de la Macarena, Sevilla, Spain), an 18 MV LINAC (Hospital General Universitario de Valencia, Spain) and a 23 MV LINAC (Universitaetsklinikum Heidelberg, Germany). Preliminary patient dose maps obtained from the UAB PADC dosemeter measurements (considering an average calibration factor for all neutron energies) are reported in this work.

  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. Operational experience of electronic active personal dosemeter and comparison with CaSo4:Dy TL dosemeter in Indian PHWR.

    Science.gov (United States)

    Singh, Vishwanath P; Managanvi, S S; Bihari, R R; Bhat, H R

    2013-01-01

    Direct reading dosemeter has been used for day-to-day radiation exposure control and management for last four decades in Indian nuclear power plants (NPPs). Recently new real time, alarm and pre-alarm on equivalent dose/dose rate, storage of dose/dose rate and maximum dose rate, user-friendly electronic active personal dosemeter (APD) has been implemented into practice for the first time at Kaiga Atomic Power Station-3&4,  of Indian NPPs. The dosemeter showed tolerance level (L) 0.1085±0.0450 compared with 0.1869±0.0729 (average±SD) for CaSO4:Dy, TL dosemeter, having narrow range trumpet curve, nil electromagnetic interference. Records of >29 000 for APD and TL dosemeter were analysed for comparasion of the measurement of the individual dose. APD followed general acceptance rule of ±25 % for dose >1 mSv. Monthly Station collective dose by TL dosemeters and APD for normal reactor operation as well as outage are found in good agreement. Operational experiences and statistical analysis support that an APD dosemeter is reasonably equivalent to CaSO4:Dy TL dosemeter. The accuracy, reproducibility and repeatability of the measurement of radiation for (137)Cs are comparable with CaSO4:Dy, TL dosemeter. Operational experience of APD during the normal operation as well as outage showed as one of the best ALARA tool for occupational dose monitoring, control, management and future outage planning.

  11. BaSO4:Eu as an energy independent thermoluminescent radiation dosimeter for gamma rays and C6+ ion beam

    Science.gov (United States)

    Sharma, Kanika; Bahl, Shaila; Singh, Birendra; Kumar, Pratik; Lochab, S. P.; Pandey, Anant

    2018-04-01

    BaSO4:Eu nanophosphor is delicately optimized by varying the concentration of the impurity element and compared to the commercially available thermoluminescent dosimeter (TLD) LiF:Mg,Ti (TLD-100) and by extension also to CaSO4:Dy (TLD-900) so as to achieve its maximum thermoluminescence (TL) sensitivity. Further, the energy dependence property of this barite nanophosphor is also explored at length by exposing the phosphor with 1.25 MeV of Co-60, 0.662 MeV of Cs-137, 85 MeV and 65 MeV of Carbon ion beams. Various batches of the phosphor at hand (with impurity concentrations being 0.05, 0.10, 0.20, 0.50 and 1.00 mol%) are prepared by the chemical co-precipitation method out of which BaSO4:Eu with 0.20 mol% Eu exhibits the maximum TL sensitivity. Further, the optimized nanophosphor exhibits a whopping 28.52 times higher TL sensitivity than the commercially available TLD-100 and 1.426 times higher sensitivity than TLD-900, a noteworthy linear response curve for an exceptionally wide range of doses i.e. 10 Gy to 2 kGy and a simple glow curve structure. Furthermore, when the newly optimized nanophosphor is exposed with two different energies of gamma radiations, namely 1.25 MeV of Co-60 (dose range- 10-300 Gy) and 0.662 MeV of Cs-137 (dose range- 1-300 Gy), it is observed that the shape and structure of the glow curves remain remarkably similar for different energies of radiation while the TL response curve shows little to no variation. When exposed to different energies of carbon ion beam BaSO4:Eu displays energy independence at lower doses i.e. from 6.059 to 14.497 kGy. Finally, even though energy independence is lost at higher doses, the material shows high sensitivity to higher energy (85 MeV) of carbon beam compared to the lower energy (65 MeV of C6+) and saturation is apparent only after 121.199 kGy. Therefore the present nanophosphor displays potential as an energy independent TLD.

  12. 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

  13. 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)

  14. Personal photon dosemeter trial--Devonport Royal Dockyard.

    Science.gov (United States)

    Collison, Roger

    2005-03-01

    To establish an understanding of the operational responses of various personal dosemeters employed at Devonport and to assess new types of dosemeters, a photon dosemeter trial was conducted. Most day-to-day exposure is to relatively low dose rates. Therefore the suitability of each dosemeter for use within the relatively low Devonport dose rate environment has been assessed. The Panasonic TLD demonstrated a good representation of the dose within the medium to higher gamma energy ranges with an unexpected under-response at lower energies. The optically stimulated luminescent dosemeter showed a varied response within a degraded (60)Co environment. With consistent under-response, the NRPB TLD and film badge were found to generally be unsuitable for sites such as Devonport. The Harshaw TLD demonstrated a good representation of the dose. The RADOS RAD80 and QFD fail to meet current best industry standards. However, the QFD is the only direct reading dosemeter suitable for use where intrinsically safe equipment is required. The RADOS RAD52 and SAIC PD 2i show a reasonable representation of the dose received but should be adjusted to read within an operational (60)Co environment. Direct ion storage and Thermo [corrected] electronic personal dosemeters showed good representations of the dose. Inherent characteristics combined with the associated systems led to the conclusion that these dosemeters should be employed for preference.

  15. Personal photon dosemeter trial-Devonport Royal Dockyard

    International Nuclear Information System (INIS)

    Collison, Roger

    2005-01-01

    To establish an understanding of the operational responses of various personal dosemeters employed at Devonport and to assess new types of dosemeters, a photon dosemeter trial was conducted. Most day-to-day exposure is to relatively low dose rates. Therefore the suitability of each dosemeter for use within the relatively low Devonport dose rate environment has been assessed. - The Panasonic TLD demonstrated a good representation of the dose within the medium to higher gamma energy ranges with an unexpected under-response at lower energies. - The optically stimulated luminescent dosemeter showed a varied response within a degraded 60 Co environment. - With consistent under-response, the NRPB TLD and film badge were found to generally be unsuitable for sites such as Devonport. - The Harshaw TLD demonstrated a good representation of the dose. - The RADOS RAD80 and QFD fail to meet current best industry standards. However, the QFD is the only direct reading dosemeter suitable for use where intrinsically safe equipment is required. - The RADOS RAD52 and SAIC PD 2i show a reasonable representation of the dose received but should be adjusted to read within an operational 60 Co environment. - Direct ion storage and Thermos electronic personal dosemeters showed good representations of the dose. Inherent characteristics combined with the associated systems led to the conclusion that these dosemeters should be employed for preference

  16. 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)

  17. Effect of thermal neutron irradiation on personal photon dosemeters

    International Nuclear Information System (INIS)

    Alberts, W.G.; Kluge, H.

    1984-01-01

    Since radiation protection dosemeters are often in use in mixed neutron-gamma fields it appeared desirable to the Commission of the European Communities to include in the intercomparison study a small measuring programme for investigating the influence of slow neutrons on personal photon dosemeters. Film dosemeters and TLD badges were sent to the PTB to be irradiated at the Thermal Neutron Reference Beam of the Research and Measuring Reactor Braunschweig, and were then sent back for evaluation. Institutes participating in this particular programme were: CEA, Fontenay-aux-Roses, CEGB, Berkeley, CNEN, Bologna, GSF, Neuherberg, TNO, Arnhem. The results for film dosemeters obtained in this intercomparison show that a careful calibration of every type of dosemeter with thermal neutrons, preferentially with low photon contamination, is desirable to achieve the appropriate corrections for the assessment of photon equivalent in a mixed field

  18. Occupational radiation exposure in Austria - results of personnel monitoring using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Duftschmid, K.E.

    1979-01-01

    The Institut fuer Strahlenschutz, Seibersdorf, can look back on more than two years of experience with the automated TLD personnel monitoring system for routine control and dose record keeping of currently about 10.000 persons per month. For more than 100.000 entries on monthly received doses have been stored so far in the Master File of the Institute's computer centre. This paper presents a survey of the statistical dose distribution in the various sectors of employment such as industry, research establishments, medical establishments and nuclear facilities, including data on the mean annual doses and the collective doses for the various sectors; information is also given on the number of cases where a dose has been in excess of the set level, and on the measured data. The data stored in the dose record keeping system allow a detailed assessment to be made of the occupational radiation exposure in Austria. (orig.) [de

  19. Determination of the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters for 125I and 103Pd brachytherapy sources relative to 60Co

    International Nuclear Information System (INIS)

    Reed, J. L.; Micka, J. A.; Culberson, W. S.; DeWerd, L. A.; Rasmussen, B. E.; Davis, S. D.

    2014-01-01

    Purpose: To determine the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters (TLD-100) for 125 I and 103 Pd brachytherapy sources relative to 60 Co. Methods: LiF:Mg,Ti TLDs were irradiated with low-energy brachytherapy sources and with a 60 Co teletherapy source. The brachytherapy sources measured were the Best 2301 125 I seed, the OncoSeed 6711 125 I seed, and the Best 2335 103 Pd seed. The TLD light output per measured air-kerma strength was determined for the brachytherapy source irradiations, and the TLD light output per air kerma was determined for the 60 Co irradiations. Monte Carlo (MC) simulations were used to calculate the dose-to-TLD rate per air-kerma strength for the brachytherapy source irradiations and the dose to TLD per air kerma for the 60 Co irradiations. The measured and MC-calculated results for all irradiations were used to determine the TLD intrinsic energy dependence for 125 I and 103 Pd relative to 60 Co. Results: The relative TLD intrinsic energy dependences (relative to 60 Co) and associated uncertainties (k = 1) were determined to be 0.883 ± 1.3%, 0.870 ± 1.4%, and 0.871 ± 1.5% for the Best 2301 seed, OncoSeed 6711 seed, and Best 2335 seed, respectively. Conclusions: The intrinsic energy dependence of TLD-100 is dependent on photon energy, exhibiting changes of 13%–15% for 125 I and 103 Pd sources relative to 60 Co. TLD measurements of absolute dose around 125 I and 103 Pd brachytherapy sources should explicitly account for the relative TLD intrinsic energy dependence in order to improve dosimetric accuracy

  20. An international intercomparison of passive dosemeters, electronic dosemeters and dose rate meters used for environmental radiation measurements

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Thompson, I.M.G.

    1995-01-01

    To assist towards the harmonisation within the EC countries, the Eastern European countries and the USA, of the measurement of environmental dose rates from photon radiation an EC sponsored intercomparison of environmental dose rate meters, electronic dosemeters and TL dosemeters was performed...

  1. Experimental determination of the photon-energy dependent dose-to-water response of TLD600 and TLD700 (LiF:Mg,Ti) thermoluminescence detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schwahofer, Andrea [Vivantes Clinic Neukoelln, Berlin (Germany). Dept. of Radiation Therapy; German Cancer Research Center, Heidelberg (Germany). Medical Physics in Radiation Therapy; Feist, Harald [Munich Univ. (Germany). Dept. of Radiation Therapy; Georg, Holger [PTW Freiburg (Germany). Calibration Lab.; Haering, Peter; Schlegel, Wolfgang [German Cancer Research Center, Heidelberg (Germany). Medical Physics in Radiation Therapy

    2017-05-01

    The aim of this study has been the experimental determination of the energy dependent dose-to-water response of TLD600 and TLD700 thermoluminescent detectors (Harshaw) in X-ray beams with mean photon energies from about 20 to 200 keV in comparison with {sup 60}Co gamma rays and 6 MV X-rays. Experiments were carried out in collaboration with the German secondary standard laboratory PTW Freiburg. The energy dependent relative responses of TLD600 and TLD700 thermoluminescence detectors were determined at radiation qualities between 30 kV{sub p} and 280 kV{sub p}. The overall uncertainty of the measured values was characterized by standard deviations varying from 1.2 to 3%. The present results agree with previous studies on the energy dependent dose-to-water response of TLD100. As an application example, the results were used to measure doses associated with X-ray imaging in image-guided radiotherapy.

  2. Individual dosemeter with ionization chamber for intervention

    International Nuclear Information System (INIS)

    Prigent, M.

    1982-01-01

    The altogether intervention ratemeter-dosemeter is a device for work condition control and for dosimetry of intervention gang in hostile medium. A portable irradiation marker with ionization chamber either carried by staff, either put at the work post, delivers an information function of the surrounding irradiation field in which moves the intervention staff. The information is processed so as the absorbed dose rate and the absorbed dose are given simultaneously. The connection between the marker and the process device is made by a cable (up to 100m) or by radio link [fr

  3. Improvement of personal dosimetry - Digital pocket dosemeter

    International Nuclear Information System (INIS)

    Radalj, Z.; Cerovac, Z.; Cerovac, H.; Brumen, V.; Prlic, I.

    1996-01-01

    Physical dosimetric surveillance of professional groups working with various radiation sources is a regular procedure in Croatia, established almost 40 years ago. Data available point out that the majority of professionals under surveillance are those employed in medical facilities, most of them working with X-ray sources. Depending on the nature of professional activities, personnel occupationally exposed to radiation sources are obliged to wear either film badge, TLD or film+TLD badge. Unfortunately, due to the line of data processing, all standard dosemeters have the same disadvantage i.e. up to 40 days delay in dose reporting, regarding the time of actual exposure. The significance of such a delay raises in cases when radiation dose was received within the short time or when technical failure on the operating unit(s) is suspected. Bearing this in mind, the additional dosimetric monitoring becomes an imperative. Therefore, we decided to introduce a palette of digital pocket dosemeters, meant to be used in different workplaces in the radiation zone, each of them being adjusted to the specificities of a particular workplace

  4. 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

  5. Dose Measurements of Parotid Glands and Spinal Cord in Conventional Treatment of Nasopharyngeal Carcinoma Using RANDO Phantom and Thermoluminescent Dosimeters

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2015-07-01

    Full Text Available Introduction Radiotherapy is regarded as the first treatment of choice for nasopharyngeal carcinoma. Despite the advantages of radiotherapy, patients may suffer from a wide range of side-effects due to the presence of many sensitive normal tissues in these regions. If the absorbed dose exceeds the tolerance level in parotid glands and the spinal cord, myelopathy, Lhermitte's sign and xerostomia cannot be avoided. Materials and Methods The head and neck of a RANDO phantom (reference man, which was regarded as a hypothetical patient with nasopharyngeal carcinoma was evaluated. The full course of treatment consisted of three phases. At the beginning of each phase, an oncologist marked conventional fields on the RANDO phantom using a simulator. For measuring the absorbed dose, Thermoluminescent Dosimeters(TLD chips (TLD-100 were utilized.The absorbed dose by TLDs was read by Harshaw 3500 TLD reader. Results The total absorbed dose was calculated by measuring the absorbed dose in each phase, multiplied by the fraction numbers of each phase; the obtained values were summed up. The results showed that the received doses by spinal cord ranged from 15.24 to 54.56 Gy. Also, the absorbed dose of parotid glands was approximately 39.23 Gy. Conclusion Considering the minimum tolerance dose the absorbed doses in the spinal cord and parotid glands were above the tolerance level. The incidence rate of xerostomia and myelopathy were higher in patients, treated by conventional methods.

  6. Energy dependence of new thermoluminescent detectors in terms of H{sub p}{sup 10} values

    Energy Technology Data Exchange (ETDEWEB)

    Miljanic, S.; Knezevic, C.; Stuhec, M.; Ranogajec-Komor, M.; Krpan, K.; Vekic, B

    2003-07-01

    The aim of this work was to determine energy dependence characteristics in terms of values of the personal dose equivalent, H{sub p}(10). The following types of thermoluminescent detectors (TLDs) were investigated: (a) two new types based on lithium borate Li{sub 2}B{sub 4}0{sub 7}:Cu,In and Li{sub 2}B{sub 407}:Cu,In,Ag; (b) two types based on the highly sensitive material LiF:Mg,Cu,P, TLD-700H and GR 200A; (c) two well-known types of LiF:Mg,Ti detectors, TLD-100 and TLD-700 and (d) highly sensitive Al{sub 2}0{sub 3}:C detectors. TLDs previously calibrated with {sup 137}Cs gamma rays were simultaneously irradiated with X ray beams in the range of mean energies between 33 and 116 keV. The irradiations were performed with detectors in polymethyl methacrylate (PMMA) holders placed on a 30 cm x 30 cm x 15 cm water phantom with PMMA walls (ISO phantom). Measured energy responses were compared with calculated data for H{sub p}(10) values. The results confirmed the satisfactory tissue equivalent characteristics of all investigated TLDs except Al{sub 2}0{sub 3}:C, which (due to its large energy dependence) is suitable for personal dosimetry only with an appropriate filter. (author)

  7. Calibration of TLD-100 powder for energies of {sup 60} Co, {sup 137} Cs, {sup 192} Ir and RX of 250, 50 kV{sub p} in absorbed dose in water with dosimetric quality control purposes for brachytherapy of high dose rate; Calibracion de polvo TLD-100 para energias de {sup 60} Co, {sup 137} Cs, {sup 192} Ir y RX de 250, 50 kVp en dosis absorbida en agua con fines de control de calidad dosimetrico para braquiterapia de alta tasa de dosis

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza C, S.P. [Programa de Maestria en Fisica Medica, Universidad Autonoma del Estado de Mexico, Paseo Tollocan S/N, esquina con Jesus Carranza, Colonia Moderna de la Cruz, 50180 Toluca, Edo. de Mexico (Mexico); Alvarez R, J.T. [Laboratorio Secundario de Calibracion Dosimetrica LSCD, Departamento de Metrologia, ININ, Carretera Federal Mexico Toluca S/N, La Marquesa, 52750 Ocoyoacac, Edo. de Mexico (Mexico)

    2006-07-01

    To help solve the traceability and quality control dosimetric problems for the users of {sup 192} Ir sources in the Mexican Republic, the Secondary Standard Dosimetric Laboratory at ININ to calibrated a batch of powder TLD- 100 (LiF: Mg,Ti) in terms of absorbed dose to water D{sub w} for the following radiation sources: {sup 60} Co, {sup 137C}s and RX 250 and 50 k Vp. Later on, the calibration is interpolated to obtain the {sup 192} Ir. The calibration radiation field is carried out with the following protocols: For the {sup 60} Co, IAEA TRS 398 protocol employing a secondary standard Farmer chamber PTW N30013, calibrated on D{sub w} at the NRC (Canada). For {sup 137} Cs the AAPM TG 43 protocol is used, in terms of air kerma strength S{sub k} determined by the air kerma K{sub a}, measured with a secondary standard chamber type thimble NE2611 traceable to the NIST (USA). For Rays X 250 and 50 k Vp, the protocol AAPM TG 61 using a tertiary standard Farmer chamber PTW 30001, with traceability to the LCIE (France) on air kerma K{sub a}. The calibration curves are built for the TLD response R{sub TLD} vs D{sub w}, they are fitted by means of a least squares fit technique with a second degree polynomial that corrects the supra linearity response. The curves are validated by the lack of fit test, and the Anderson Darling normality test. Later on, the sensibility factors are interpolated for the sources of {sup 192} Ir: Micro Selectron and Vari Source. Two capsules are sent to two hospitals to verify a nominal D{sub w} = 2 Gy, in the first one an underestimate of the D{sub w} is obtained, and in other one an overestimation is presented. Finally, the expanded uncertainty associated to D{sub w} and the F{sub s} are calculated. (Author)

  8. Absorbed dose measurements in mammography using Monte Carlo method and ZrO{sub 2}+PTFE dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Duran M, H. A.; Hernandez O, M. [Departamento de Investigacion en Polimeros y Materiales, Universidad de Sonora, Blvd. Luis Encinas y Rosales s/n, Col. Centro, 83190 Hermosillo, Sonora (Mexico); Salas L, M. A.; Hernandez D, V. M.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Pinedo S, A.; Ventura M, J.; Chacon, F. [Hospital General de Zona No. 1, IMSS, Interior Alameda 45, 98000 Zacatecas (Mexico); Rivera M, T. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F.(Mexico)], e-mail: hduran20_1@hotmail.com

    2009-10-15

    Mammography test is a central tool for breast cancer diagnostic. In addition, programs are conducted periodically to detect the asymptomatic women in certain age groups; these programs have shown a reduction on breast cancer mortality. Early detection of breast cancer is achieved through a mammography, which contrasts the glandular and adipose tissue with a probable calcification. The parameters used for mammography are based on the thickness and density of the breast, their values depend on the voltage, current, focal spot and anode-filter combination. To achieve an image clear and a minimum dose must be chosen appropriate irradiation conditions. Risk associated with mammography should not be ignored. This study was performed in the General Hospital No. 1 IMSS in Zacatecas. Was used a glucose phantom and measured air Kerma at the entrance of the breast that was calculated using Monte Carlo methods and ZrO{sub 2}+PTFE thermoluminescent dosemeters, this calculation was completed with calculating the absorbed dose. (author)

  9. Thermoluminescent response of LiF: Mg, Cu, P (GR-200) below an electron beam of 6 MeV

    International Nuclear Information System (INIS)

    Torijano C, E.F.S.; Azorin N, J.; Villasenor N, I.; Lujan C, P.J.; Rivera M, T.

    2007-01-01

    Full text: In this work the experimental results of studying the thermoluminescent response (TL) of LiF:Mg,Cu,P (GR-200) previously irradiated with 6 MeV electrons are presented. The electrons beam was generated by a Lineal Accelerator VARIAN I for medical use. The lineal accelerator is installed in the General Hospital of Mexico (HGM). A lot of 25 thermoluminescent dosemeters (DTL) was used. The mass and volume of each one of them were determined. Obtaining a variation of 14% in standard deviation (SD). The DTLs were irradiated to an energy of 6 MeV. The dose given to the DTL was of 50 c Gy. The linearity of the response of the GR-200 also was determined. (Author)

  10. Dosimetric characteristics of a TLD dosemeter with extremities

    International Nuclear Information System (INIS)

    Molina P, D.; Diaz B, E.; Lien V, R.

    1999-01-01

    It was designed a TLD dosemeter for the monitoring of the extremities. This one consists in a metallic ring with a circular orifice where is arranged a T L detector of LiF: Mg,Ti (Model JR1152C) 5 x 5 x 0.8 mm 3 covered by a polyethylene fine layer. In this work were studied the dosimetric properties of the dosemeter for its application in the dosimetry of extremities for photonic radiation. the results obtained allow conclude that the designed dosemeter can be used for the extremities monitoring. (Author)

  11. Dating of the archaeological site 'El Tigre' by the thermoluminescent method

    International Nuclear Information System (INIS)

    Portilla, R. De la; Gonzalez, P.R.; Mendoza, D.; Vargas, E.; Ramirez, A.

    2007-01-01

    Full text: The dating of pre hispanic pottery, is supported by techniques such as stratigraphy, typology, in physical and chemical procedures, as the analysis of 14 C and the thermoluminescence (TL). The last one permits us obtain absolute dating of archaeological pottery with an acceptable precision. In this work we apply the applied the thermoluminescent technique to verify the age of the Pre-Classic and Classic Terminal periods proposed for the archaeological site 'El Tigre', Campeche. The samples were obtained during a work period and the radiation of the ground of background (emitted by the ground), as well as the contribution of the cosmic radiation was measured with thermoluminescent dosemeters of LiF: Mg,Cu,P + PTFE, put in the sample zone. The preliminary results indicate that not all the analyzed samples can be dated. The viability of the dating of the samples is discussed based on the fact and function of the presence of certain crystalline phases such as calcite and quartz. The discussion is complemented emphsizing the importance of handling the conditions of handling of samples. (Author)

  12. 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)

  13. 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)

  14. Active electronic personal dosemeter in interventional radiology

    International Nuclear Information System (INIS)

    Prlic, I.; Suric Mihic, M.; Vucic, Z.

    2008-01-01

    A recently developed active electronic personal dosemeter (AEPD) was utilised in order to measure the levels and the structure of occupational exposure to scattered X-ray radiation of medical staff who performed percutaneous revascularisation therapy that involves interventional radiology (IR) on the pelvis and upper leg arteries. The AEPDs, placed on the operators' and assistants' chests, that is, above the protective apron, continuously measured and recorded the received doses and, as a novelty, dose rates as a function of time, thus yielding a unique record of occupational doses and dose rates pattern at the working place. This paper presents and discusses one typical daily pattern in which seven percutaneous interventions were performed. (authors)

  15. Measurement analysis using the Fricke dosemeter

    International Nuclear Information System (INIS)

    Pedrosa, G.A.C.; Dantas, C.C.

    2003-01-01

    The Fricke dosemeter has been used for absolute determination of the radiation dose between 40 and 350 Gy for X-rays, Gamma rays and fast electrons energies. The great inconvenient of that dosimetric system is the impossibility of using for measurements of exposure or low dose rates. A Fricke dosimetry system was implanted at the Nuclear Sciences Regional Center (CRCN), in Recife, Pernambuco state, Brazil, for the determination of radiation doses for spectrometry and mass dosimetry with plasma source. The statistical analysis of the obtained results have shown that using the spectrometric method that system cna be used for maintenance of factors of CRCN standard calibrations and the dose assessment thru mail system of radiotherapy centers of the country

  16. A CR-39 track dosemeter for routine individual neutron monitoring

    International Nuclear Information System (INIS)

    Luszik-Bhadra, M.; Alberts, W.G.; Dietz, E.; Guldbakke, S.; Matzke, M.; d'Errico, F.

    1994-01-01

    A personal neutron dosemeter for routine individual monitoring is proposed. It is based on a CR-39 track detector covered on three separate areas by converters with different boron contents and inserted into a commercial TLD albedo dosemeter capsule. The dose readings from three areas of the electrochemically etched CR-39 detector are combined to yield a dose equivalent response which is almost independent of the incident neutron energy in the range from thermal neutrons up to 20 MeV. In addition, the dose contributions of thermal, intermediate and fast neutrons can be determined separately. Unlike the TLD albedo dosemeter, which in general requires prior in-field calibration and whose use is then restricted to that field, this dosemeter can be used in neutron fields without any knowledge of the spectral distribution with the same calibration factor. The angular dependence of the dosemeter's response has been measured and compared with that of the directional dose equivalent H'(10). The lower limit of detection is 0.15 mSv. It is possible to obtain an independent, second dose reading from the same Cr-39 detector for neutron energies above 100 keV. The dosemeter has also been successfully tested for use in accident dosimetry applying chemical etching and an optical density reading of the CR-39 detector. (author)

  17. Thermoluminescence dating of dental enamel

    International Nuclear Information System (INIS)

    Benkoe, L.; Koszorus, L.

    1980-01-01

    Thermoluminescent response of the synthetic hydroxylapatite was studied, this material being the fundamental inorganic constituent of dental enamel. In order to make an attempt at archaeological TL dating of teeth, a chemical deproteination procedure of enamel was established, and the pre-dose effects of separated mineral grains extracted from 100 to 6000 years old human teeth were investigated. (orig.)

  18. 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

  19. Photoluminescence and thermoluminescence properties of ...

    Indian Academy of Sciences (India)

    WINTEC

    Kanazawa T 1989 Inorganic phosphate materials, in Materials science monographs (Amsterdam: Elsevier) 52. Kottaiswamy M, Mohan Rao M and Jayakumar D 1997 Proc. nat. conf. on luminescence and its applications (New Delhi: Allied Publishers) p. 153. Mckeever S W S 1985 Thermoluminescence of solids (Cam-.

  20. Photoluminescence and thermoluminescence properties of ...

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. The suitability of calcium phosphate crystals for thermoluminescence dosimetry (TLD) applica- tions is investigated, owing to their equivalence to bone mineral. The α and β phases of tricalcium phosphate. (TCP) were synthesized through wet precipitation and high temperature solid state routes and doped with Dy.

  1. 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)

  2. Thermoluminescent dose measurements on board Salyut type orbital stations

    International Nuclear Information System (INIS)

    Akatov, Yu.A.; Arkhangelskij, V.V.; Aleksandrov, A.P.

    1984-06-01

    A small, vibration- and shock-resistant thermoluminescent dosemeter (TLD) system - named PILLE - was developed for orbital stations at the Central Research Institute for Physics, Hungary, to measure the cosmic radiation dose on-board. The first on-board measurements with this system were performed by B. Farkas, the Hungarian astronaut, on the Salyut-6 space station in 1980. The same instrument was used by other crews in the following years. Doses measured at different sites in Salyut-6 are presented. The dose rates varied from 0.7 to 0.11 mGy.day -1 . After the first cosmic measurements, the system was further developed. The minimum detectable dose of the new TLD system is 1 μGy, i.e. less by one order of magnitude than that of the former system. The self-irradiation dose rate of the TLD bulbs is also reduced by more than an order of magnitude to 10 nGy.h -1 , by use of potassium-free glass for the bulb envelope. This new type of PILLE TLD system is currently on-board Salyut-7. The dose rates (0.12-0.23 mGy.day -1 ) measured in 1983 are presented in detail. (author)

  3. 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)

  4. Thermoluminescence dating (TL-Dating): an absolute method for archeological dating of ceramic base materials

    International Nuclear Information System (INIS)

    Wan Saffiey Wan Abdullah

    2004-01-01

    Thermoluminescence dating is one of the known techniques that have been established in many laboratories across the regions. This technique is capable to date the archeological ceramic base materials and provides an absolute measurement with an accuracy of 5%. The study involves the dating of ceramic clay from historical site at Sungai Mas, Kuala Muda, Kedah. Pieces of broken poetry of archeological sample excavated by the Museum Department and Antiquity (JM4) have been dated using the TLD techniques at MINT laboratory. A TLD dosemeter of LiF chips is used for the background and sample dose measurement. The preparation of sample and the calibration techniques for the estimation of palaedose or dose presented in the sample since distant past is established. Results indicate that the samples are in the era of civilization from 200BP to 1600BP. Error factors associated in the measurement procedures are also discussed

  5. Development of radiophotometric dosemeters of high sensitivity using plastic scintillators as light intensifiers

    International Nuclear Information System (INIS)

    Mesquita, C.H. de; Hamada, M.M.

    1987-01-01

    The use of rectangular plates of plastic scintillators as film holders in conventional photographic dosemeters is reported. The efficiency of their use as light converters for increase the sensitivity of these dosemeters are studied. (M.A.C.) [pt

  6. 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)

  7. Improvement of the calibration technique of clinical dosemeters

    International Nuclear Information System (INIS)

    Ehlin Caldas, L.V.

    1988-08-01

    Clinical dosemeters constituted of ionization chambers connected to electrometers are usually calibrated as whole systems in appropriate radiation fields against secondary standard dosemeters in calibration laboratories. This work reports on a technique of component calibration procedures separately for chambers and electrometers applied in the calibration laboratory of IPEN-CNEN, Brazil. For electrometer calibration, redundancy was established by using a standard capacitor of 1000pF (General Radio, USA) and a standard current source based on air ionization with Sr 90 (PTW, Germany). The results from both methods applied to several electrometers of clinical dosemeters agreed within 0.4%. The calibration factors for the respective chambers were determined by intercomparing their response to the response of a certified calibrated chamber in a Co 60 calibration beam using a Keithley electrometer type 617. Overall calibration factors compared with the product of the respective component calibration factors for the tested dosemeters showed an agreement better than 0.7%. This deviation has to be considered with regard to an uncertainty of 2.5% in routine calibration of clinical dosemeters. Calibration by components permits to calibrate ionization chambers one at a time for those hospitals who have several ionization chambers but only one electrometer (small hospitals, hospitals in developing countries). 6 refs, 2 figs, 2 tabs

  8. Thermoluminescence Dosimetry Applied to Radiation Protection

    DEFF Research Database (Denmark)

    Christensen, Poul; Bøtter-Jensen, Lars; Majborn, Benny

    1982-01-01

    , fading, and LET dependence. The applications of thermoluminescence dosimetry in routine personnel monitoring, accident dosimetry, u.v. radiation dosimetry, and environmental monitoring are discussed with particular emphasis on current problems in routine personnel monitoring. Finally, the present state......This is a general review of the present state of the development and application of thermoluminescence dosimetry (TLD) for radiation protection purposes. A description is given of commonly used thermoluminescent dosimeters and their main dosimetric properties, e.g. energy response, dose range...

  9. Application of chemical dosemeters during the irradiation of agricultural products

    International Nuclear Information System (INIS)

    Kovacs, A.; Stenger, V.; Foeldiak, G.

    1983-01-01

    The joint recommedation by the FAO, WHO and IAEA in 1981 proposed the unrestricted permission of food irradiation under the dose value of 10 kGy (1 Mrd). The chemical dosemeters presented in the paper cover the dose range of 30 Gy to 1 MGy for use to food irradiation safety measurements. The Fricke dosemeter was used in the 50-400 Gy range at radappertization operations of onion, poppy and potato. The alcoholic chlorobenzene dosemeter with oscillometric analysis was applied successfully at low (0.4-4 kGy) ranges, primarily for irradiation dose monitoring of fruits, vegetables, refrigerated poultry etc. The conductometry could be used for dosimetry in the range of 60 Gy to 1 MGy. (Sz.J.)

  10. Elaboration And Study Of Transfer Alanine/ESR Dosemeters

    International Nuclear Information System (INIS)

    Torres G, Luz A.

    1996-01-01

    The dosimetry is the dose measure imparted by the energy from the ionizing radiation to the matter. The dosemeters is the means used for the determination of such a dose. Diverse dosimetric classes exist, this classification depends in essence of the energy involved in the irradiation process and of its application necessity. It is as well as in radiological protection movie dosemeter is used, and TLD, in the calibration of units, as those of cobalt, the ionization cameras are used, in the detection of superficial contamination the accountants Geiger Muller and proportional etc. The transfer dosimeter Alanine/ESR is used, object of the present work, is characterized because after reading the registered dose, the information is conserved and it can be transferred and read in any team of ESR. Likewise the following dose that is imparted will be added to the previous one registered, this indicates that the dosemeters is of integral character. In the spectra taken ESR, it is determined that the integral double or area under the curve of the spectrum ESR is proportional to the concentration of free radicals generated by the radiation ionization and in turn this concentration is proportional to the dose received by the pills; in last, these proportionality relationships take to that the area under the curve of the spectrum main ESR is proportional to the radiation dose received by the alanine dosemeters. This dosemeter seeks to be an economic alternative that it will lend the calibration service that today offers the ionization Cameras or the acrylic red industrial dosemeters

  11. Feasibility study of an innovative active neutron dosemeter

    Science.gov (United States)

    Hawkes, N. P.; Iwatschenko-Borho, M.; Leder, E.; Taylor, G. C.

    2017-11-01

    Prototypes of a novel pocket-sized active neutron dosemeter, based on a sensor made from the scintillator material Cs2LiYCl6:Ce (CLYC) coupled to a silicon photomultiplier (SiPM), were exposed to several well-characterised neutron fields produced at the National Physical Laboratory (NPL), UK. 6Li-enriched CLYC is extremely interesting as a dosemeter sensor because it can detect not only gamma rays but also thermal and fast neutrons, gammas being distinguishable from neutrons by pulse shape discrimination. Thermal and low energy neutrons are detected by the 6Li(n, α)3H reaction, which gives rise to a well-defined peak in the pulse height spectrum. Fast neutrons typically interact via 35Cl(n, p) or (n, α) reactions, and the kinetic energy of the reaction product gives rise to a pulse height spectrum that relates fairly straightforwardly to the original neutron energy spectrum. Because of this spectrometry capability, such a dosemeter has the potential to retain its accuracy to a much greater extent, compared with conventional devices, when used in radiation fields that differ from the one used for calibration. SiPMs are low-power and compact, allowing the prototype dosemeters produced for testing to fit entirely within a standard existing personal dosemeter housing. Tests were carried out in the low-scatter neutron facility at NPL, with measurements made both on-phantom and free-in-air. The former were done to evaluate the device's performance as a personal dosemeter, and the latter to explore its potential as a very light neutron area survey meter. In this paper the experimental results are presented, performance issues encountered during the trials are discussed, and preferred application scenarios are proposed.

  12. Official dosimetry with personal electronic dosemeters - The framework in Germany

    International Nuclear Information System (INIS)

    Czarwinski, R.; Kaulard, J.; Pfeffer, W.

    2007-01-01

    In Germany, personal electronic dosemeters (AEPDs) are presently applied mainly for operational radiation protection monitoring particularly in nuclear power engineering companies, large hospitals and research centres. This is done in addition to the official dosimetry of record. Therefore, frequently, double monitoring occurs - officially and operationally. A crucial advantage of AEPDs compared with passive dosemeters is the ability to adapt the monitoring period to the working time in controlled areas and to allow an immediate readout of the dose after leaving the controlled area, e.g. a job-related monitoring is possible by correlating the readout dose with the job performed. Germany started a general research project, consisting of two parts, for an optimised implementation of personal electronic dosemeters into official dosimetry. The use of AEPDs as official dosemeters depends on an approval by Federal and Federal State ('Laender') authorities as an official dosimetry system, which has to comply with special requirements ensuring that the legal requirements are fulfilled. The formulation of these special requirements is in the focus of part one of the research project, supervised by the Federal Office for Radiation Protection (BfS) and performed by the Gesellschaft fuer Anlagen-und Reaktorsicherheit (GRS) mbH. As a result of part one, a framework was developed which is the basis for a future technical implementation project. Part one is described in the paper, while part two is still to be initiated and will deal with the implementation and testing phase of the introduction of personal electronic dosemeters as official dosemeters. (authors)

  13. Validation of response simulation methodology of Albedo dosemeter

    International Nuclear Information System (INIS)

    Freitas, B.M.; Silva, A.X. da

    2016-01-01

    The Instituto de Radioprotecao e Dosimetria developed and runs a neutron TLD albedo individual monitoring service. To optimize the dose calculation algorithm and to infer new calibration factors, the response of this dosemeter was simulated. In order to validate this employed methodology, it was applied in the simulation of the problem of the QUADOS (Quality Assurance of Computational Tools for Dosimetry) intercomparison, aimed to evaluate dosimetric problems, one being to calculate the response of a generic albedo dosemeter. The obtained results were compared with those of other modeling and the reference one, with good agreements. (author)

  14. The evaluation of multi-element personal dosemeters using the linear programming method

    International Nuclear Information System (INIS)

    Kragh, P.; Ambrosi, P.; Boehm, J.; Hilgers, G.

    1996-01-01

    Multi-element dosemeters are frequently used in individual monitoring. Each element can be regarded as an individual dosemeter with its own individual dose measurement value. In general, the individual dose values of one dosemeter vary according to the exposure conditions, i. e. the energy and angle of incidence of the radiation. The (final) dose measurement value of the personal dosemeter is calculated from the individual dose values by means of an evaluation algorithm. The best possible dose value, i.e. that of the smallest systematic (type B) uncertainty if the exposure conditions are changed in the dosemeter's rated range of use, is obtained by the method of linear programming. (author)

  15. Thermoluminescence of Ge- and Al-doped SiO2 optical fibers subjected to 0.2-4.0 Gy external photon radiotherapeutic dose

    International Nuclear Information System (INIS)

    Hossain, I.; Wagiran, H.; Yaakob, N.H.

    2013-01-01

    In this work, we studied the thermoluminescence response of Ge- and Al-doped optical fibers, its linearity, energy dependence, and sensitivity. The Ge-doped optical fibers demonstrate useful TL properties and represent an excellent candidate for use in TL dosimetry of ionizing radiation. The TL response increases monotonically over a wide photon dose range, from 0.2 Gy to 4.0 Gy. The TL results for these fibers have been compared with similar TL data for phosphor TLD-100. Commercially available Al- and Ge-doped optical fibers have both been found to yield a linear dose-TL signal relationship, although the Al-doped fiber provides only 5 % of the sensitivity of the Ge-doped fibers. The TL characteristics of Ge-doped optical fiber, plus its small size (125 μm diameter), high flexibility, ease of handling, and low cost compared with other TL materials, make this commercial optical fiber a very promising TL material for use in medicine, industry, reactor operation, and a variety of other areas. (author)

  16. A kinetic model of zircon thermoluminescence

    NARCIS (Netherlands)

    Turkin, A.A.; Es, H.J. van; Vainshtein, D.I.; Hartog, H.W. den

    A kinetic model of zircon thermoluminescence (TL) has been constructed to simulate the processes and stages relevant to thermoluminescent dating such as: filling of electron and hole traps during the excitation stage both for natural and laboratory irradiation; the time dependence of fading after

  17. 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

  18. 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)

  19. Thermoluminescence, luminescence optically stimulated and creation of defects in alkaline halogenides contaminated with Europium

    International Nuclear Information System (INIS)

    Barboza F, M.

    1999-01-01

    The alkaline halogenides have been subject matter of investigations related with the search of sensor materials for X-ray bidimensional images or optical memories. The understanding of the damage formation processes generated by ionizing and non-ionizing radiations is important for the correct design of devices that working as detectors and dosemeters of both type of radiations. In this work we present the investigation results related with the defects produced by the ionizing radiation type X and ultraviolet light in the range of 200-360 nm in crystals of KCl: Eu 2+ and KBr:Eu 2+ . It is examined the thermoluminescence and luminescence spectra with the purpose of identifying the exciton processes, owing to the excitation of the halogenide ions in which the primary defects correspond to the F and H centers. It has been found that the 400-600 nm emission is associated with the luminescence type that in his turn can be associated with autotrapped excitons perturbed by the impurity. On the other hand, it is examined the emission spectra of the luminescence optically stimulated in crystals of KBr: Eu 2+ and KCl: Eu 2+ finding too that such materials would be used as optical memories susceptible of to store information, and through of photostimulation to read this. It was determined that the F centers participate in the luminescence optically stimulated in these crystals, as well as too in the recombination processes responsible by the thermoluminescent emission. (Author)

  20. Development of new dosemeters of CaSO4

    International Nuclear Information System (INIS)

    Santos, Ana Gabryele M. dos; Junot, Danilo O.; Souza, Divanizia N.

    2016-01-01

    Thermoluminescent dosimeters (TLDs) are widely used in in vivo dosimetry because of their simple production, viability for dose determination in difficult geometries and their reusability. The motivation of this work was to produce CaSO 4 crystals doped with thulium (Tm) and analyze their thermoluminescent (TL) properties. The crystals were produced by a variation of slow evaporation route, and TL curves showed emission peaks centered around 190 ° C and 320 ° C after irradiation with a 90 Sr / 90 Y source. Thermoluminescent properties such as linearity, reproducibility and fading were evaluated. The CaSO 4 :Tm samples produced proved feasible for dosimetry purposes. (author)

  1. 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.

  2. 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

  3. 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

  4. Viability of the Fricke dosemeter doped with methylene blue

    International Nuclear Information System (INIS)

    Souza, V.L.B.; Santos, C.D.A.; Rodrigues, K.R.G.; Cunha, M.S.; Figueiredo, M.D.C.; Melo, R.T.

    2009-01-01

    This work aims to find the possible utilization of the Fricke dosemeter doped with methylene blue (FMB) for the dosimetry of photodynamic therapy. The FMB was irradiated wit X rays and light emitted diodes demonstrating positive answers to the stimulus, being probably to be used for dosimetric objectives

  5. Graphite mixed magnesium borate TL dosemeters for beta ray dosimetry

    DEFF Research Database (Denmark)

    Prokic, M; Christensen, Poul

    1984-01-01

    Sintered MgB4O7:Dy dosemeters with graphite contents from 1 to 10% were investigated for application for personnel dosimetry. Data are given on dose response, dose threshold, reproducibility, beta energy response and fading. Furthermore, results from practical field experiments are presented...

  6. Effective energies and exposure determinations of two different energy X-ray beams incident on a personnel monitor

    International Nuclear Information System (INIS)

    Okuno, E.; Cruz, M.T. da

    1984-01-01

    The effective energy of one X or gamma ray beam can be determined by means of two thermoluminescent (TL) dosemeters mounted between suitable filters. However, it has been observed that personnel monitors exposed to two different energy ionizing radiations provide different effective energies depeding on the type of TL phosphor used. This fact could be a powerful tool for identifying exposures to radiation with quite different effective energies which are very common in practice. Two types of TL dosemeters were used : pellets of cold pressed natural fluoride and NaCl developed in our own laboratory, and LiF, TLD-100 from Harshaw Chemical Co.. Experimental results obtained with these combined dosemeters after irradiation with different sets of exposures and energy values of ionizing radiations are also presented. (Author) [pt

  7. The thermoluminescence as tool in the reconstruction of volcanic events

    International Nuclear Information System (INIS)

    Ramirez L, A.; Schaaf, P.; Martin del Pozzo, A.L.; Gonzalez M, P.

    2000-01-01

    Within the Mexican land a great number of volcanoes are situated which a considerable part of them are still active. The relevance of dating pomex deposits, ash or lava of these poly genetic volcanoes is to determine the periodicity and magnitude of the volcanic events happened. In this work is presented the preliminary result of the dating by thermoluminescence in a pomex of a pyroclastic flux coming from a volcano in the state of Puebla with the purpose of providing elements to the knowledge which describe the eruptive history of the explosive volcanism at center of Mexico. For the sample dating the volcanic glasses of pomex were separated and it was applied the fine grain technique with a grain size between 4-11 μ m. In order to calculate the rate of annual dose it was carried out the following: in the determination of 238 U and 232 Th radioisotope concentration was used the neutron activation technique in a nuclear reactor, in the determination of the K 40 radioisotope was used a scanning electron microscope, the rate of environmental and cosmic dose was measured arranging Tl dosemeters of CaSO 4 : Dy in the sampling place. In order to calculate the paleodoses it was carried out the following: the equivalent dose (Q) was determined starting form the additive method and the supra linearity factor (I) starting from regenerative method and in both methods the irradiated process was realized with a 90 Sr beta source. With the above determinations it was calculated a paleodoses of 231 Gy and a rate of annual dose of 6.074 x 10 -3 Gy/year, estimating an age of: Age pomez = 231 Gy / 6.074 Gy x 10 -3 Gy /year = 38030 ± 4000 years. (Author)

  8. Energy response of different types of RADOS personal dosemeters with MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P) TL detectors.

    Science.gov (United States)

    Obryk, B; Hranitzky, C; Stadtmann, H; Budzanowski, M; Olko, P

    2011-03-01

    The photon energy response of different RADOS (Mirion Technologies) personal dosemeters with MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P) thermoluminescence (TL) detectors was investigated. Three types of badges were applied. The irradiation with reference photon radiation qualities N (the narrow spectrum series), and S-Cs and S-Co nuclide radiation qualities, specified in ISO 4037 [International Organization for Standardization (ISO). X and gamma reference radiations for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy. ISO 4037. Part 1-4 (1999)], in the energy range of 16-1250 keV, were performed at the Dosimetry Laboratory Seibersdorf. The results demonstrated that a readout of a single MTS-N or MCP-N detector under the Al filter can be used to determine Hp(10) according to requirements of IEC 61066 [International Electrotechnical Commission (IEC). Thermoluminescence dosimetry systems for personal and environmental monitoring. International Standard IEC 61066 (2006)] for TL systems for personal dosimetry. The new RADOS badge with the experimental type of a holder (i.e. Cu/Al filters) is a very good tool for identifying the radiation quality (photon energy).

  9. Production of LiF films for dosimetric thermoluminescence application; Producao de filmes de LiF para aplicacao em dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Mauricio, Claudia Lucia de Pinho

    2000-12-01

    This work studies the LiF monolayer and multilayer polycrystalline film's dosimetric properties. The films were produced by electron beam evaporation technique in aluminium and stainless steel substrates maintained at several temperatures. As dosimetric variable, the intensity of the thermoluminescent (TL) glow curve of the films was used. effects of the substrate type and temperature; of the addition of layers of Mg F{sub 2} NaF and Cu F{sub 2} to the LiF films; and of thermal treatments in the TL response of the produced films were studied. The microstructural characterization of the films was accomplished through measures of scanning electronic microscopy and grazing incidence X-rays diffraction analysis. The dosimetric characterization was made of gamma radiation exposure in a {sup 60} Co source, with kerma from 0,1 to 500 Gy. Studies of reproducibility, homogeneity, stability and other environmental effects were also made. LiF and Cu F{sub 2}: LiF; Mg F{sub 2} films were the only ones that presented mechanical stability and reproducibility of the TL emission. There is a strong indication of some correlation between the residual tension fields inside the films and the intensity of its TL emission peaks. LiF monolayer films present supralinear behaviour from 0,2 to 100 Gy. These films present a main TL glow peak around 150 deg C, whose half-time is about 30 days. Its volumetric sensitivity can reach about 60 times that of LiF powder and about 0,25 that of TLD100 (LiF:Mg, Ti commercial dosimeter from Harshaw Chemical Co.) The homogeneity and reproducibility inside a same film batch is better than 12% for 95% confidence level. Cu F{sub 2} : LiF: Mg F{sub 2} films present linear behaviour from 3 to 500 Gy and its main TL glow peak around 200 deg C did not present any fading for a a period of 30 days, in laboratory conditions. This glow peak is characteristic of the Mg doping of LiF, which confirms the diffusion of Mg ions from the Mg F{sub 2} layer to the Li

  10. 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

  11. 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

  12. Thermoluminescence (TL) of Egyptian Blue

    Energy Technology Data Exchange (ETDEWEB)

    Schvoerer, M.; Delavergne, M.-C.; Chapoulie, R.

    1988-01-01

    Egyptian Blue is a synthesized crystalline pictorial pigment with formula CaCuSi/sub 4/O/sub 10/. It has been used in Egypt and Mesopotamia from the 3rd millenium B.C. A preliminary experiment on a recently synthesized sample showed that this pigment is thermoluminescent after ..beta.. irradiation (/sup 90/Sr). As the signal intensity grows linearly with the administered dose within the temperature range commonly used in TL dating, we have been looking for this phenomenon from archaeological pigments. It was encountered with two samples found in excavation. From its intensity and stability we concluded that Egyptian Blue can be dated using TL. This first and positive result encouraged us to extend the method to other types of mineral pigments synthesized by early man, and to suggest that it may be used for direct dating of ancient murals.

  13. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    CERN Document Server

    Yuen, P S; Frketich, G; Rotunda, J

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of ligh...

  14. 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.)

  15. Thermoluminescent characteristics of new pre-calibrated dosimeters (TLD) in commercially available readers for selected applications

    Science.gov (United States)

    Tawil, R. A.; Pontikos, P.; Szalanczy, A.; Velbeck, K.; Bruml, W.; Rotunda, J. E.

    1994-12-01

    This paper reports the performance of newly developed pre-calibrated Thermoluminescent Dosimeters (TLD) with a description and performance results for two commercially available TLD readers. Introduced for use in basic research, medical diagnostics and therapy applications, the Harshaw Model 5500 Automatic TLD Reader evaluates up to 50 dosimeters (rods, chips, disks, μ-cubes) per loading; the Harshaw Model 3500 Manual TLD Reader evaluates single dosimeters and powder. Tests were conducted using the International Electrotechnical Commission (IEC) guidelines for TLD readers to determine system performance and compliance. Both instruments passed the compliance standards in all tests established by the IEC: detection thresholds for both instruments were less than 10μGy, reproducibility was better than 0.7%, sensitivity to ambient light was less than 0.2 Hmax (where Hmax is the maximum detection threshold), TL residue was less than 1% of the total integral charge, stability less than 1% deviation after a 24 hour warm-up period, linearity was within specification, test light stability was under 1%, and power leakage requirements set forth by UL-544 (less than 500 μA AC RMS leakage) was less than 42 μA AC RMS in all cases. The characteristics of newly introduced, factory calibrated, extruded TLD-100 rods were investigated by studying the consistency of the Element Correction Coefficients (ECCs) under a variety of conditions. The ECC ( / xi) relates an individual dosimeter's response, xi, to the mean response, , of the group. Supralinearity effects and the validity of ECCs generated at 1 cGy for use in the 50-900 cGy dose range were characterized and reported. The results for two specific applications, phantom studies with 60Co and at four Orthovoltage energies are also reported. Portability of Element Correction Coefficients from reader to reader was achieved with a relative standard deviation of less than 1.7%. The relative standard deviation of five TLDs exposed to

  16. Characteristic of the dosemeter used by the service of film dosimetry in the CPHR

    International Nuclear Information System (INIS)

    Capote Ferrera, E.A.; Diaz Bernal, E.; Manzano de Armas, J.F.

    1998-01-01

    Characteristic of the dosemeter used by the service of dosimetria filmica of the CPHR.The use of film dosemeter brings I get the aquisition first it gives data that it includes its evaluation regarding the calibration magnitude and second the interpretation of these data in terms of the magnitude of personal dose, such as the equivalent dose (ICRU 47) or to the effective dose (ICRP 60). presently work the results of the study of the characteristics of the dosemeters are picked up

  17. 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)

  18. Household and workplace chemicals as retrospective luminescence dosemeters

    DEFF Research Database (Denmark)

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

    2002-01-01

    In the development of techniques for the retrospective assessment of the close absorbed by communities living and working adjacent to the site of a nuclear accident, attention has concentrated on the use Of natural minerals such as quartz and feldspar as dosemeters. These minerals are widely foun...... such chemicals and this paper reports oil the OSL sensitivity, the size of the residual close immediately after manufacture, stability and derived minimum detection limits....

  19. Aluminium nitrate ceramics: A potential UV dosemeter material

    DEFF Research Database (Denmark)

    Trinkler, L.; Bøtter-Jensen, L.; Berzina, B.

    2002-01-01

    The ceramic material AIN-Y2O3 is proposed as a potential ultraviolet radiation (UVR) dosemeter using optically stimulated luminescence (OSL) and thermally stimulated luminescence (TL). Experimental studies have shown that AIN ceramics exhibit attractive characteristics suitable for practical UV...... of Al2O3:C; and (4) a large dynamic range TL signal (5 orders of magnitude). Although there is relatively high fading, it is demonstrated that AIN is a feasible material for UVR dosimetry using short integration times....

  20. Micro-dosemeter instrument (MIDN) for assessing risk in space

    International Nuclear Information System (INIS)

    Pisacane, V. L.; Dolecek, Q. E.; Malak, H.; Cucinotta, F. A.; Zaider, M.; Rosenfeld, A. B.; Rusek, A.; Sivertz, M.; Dicello, J. F.

    2011-01-01

    Radiation in space generally produces higher dose rates than that on the Earth's surface, and contributions from primary galactic and solar events increase with altitude within the magnetosphere. Presently, no personnel monitor is available to astronauts for real-time monitoring of dose, radiation quality and regulatory risk. This group is developing a prototypic instrument for use in an unknown, time-varying radiation field. This micro-dosemeter-dosemeter nucleon instrument is for use in a space-suit, spacecraft, remote rover and other applications. It provides absorbed dose, dose rate and dose equivalent in real time so that action can be taken to reduce exposure. Such a system has applications in health physics, anti-terrorism and radiation-hardening of electronics as well. The space system is described and results of ground-based studies are presented and compared with predictions of transport codes. An early prototype in 2007 was successfully launched, the only solid-state micro-dosemeter to have flown in space. Published by Oxford Univ. Press on behalf of the US Government 2011. (authors)

  1. Official dosimetry with individual electronic dosemeters - the concept in Germany

    International Nuclear Information System (INIS)

    Czarwinski, R.; Kaulard, J.; Pfeffer, W.

    2005-01-01

    Full text: Presently, in Germany passive dosemeters (film batches, RPL, TLD) are used for the official individual monitoring of occupational exposed personal. The application of electronic individual dosemeters (EPD) is carried out mainly for the operative radiation protection control particularly in nuclear power engineering companies, big hospitals und research centres. This means in such institutions double monitoring exists - legally and operatively. A crucial advantage of EPD compared to passive dosemeter is the possibility to adapt the monitoring period to the working time in the control area, e.g. a job related monitoring is available. Germany started a project for an optimized implementation of EPD into the official dosimetry. Objective of the project whose results will be described in the paper is the harmonization of radiation protection of companies workers and outside workers concerning the record of individual and job related exposures. The approval of the EPD by the Federal and Laender authorities as an official dosimetric system demands the implementation of special requirements concerning the data acquisition, data transfer and data evaluation. These issues are focuses of the Federal research project, supervised by the Federal Office for Radiation Protection (BfS) and performed by the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS), Cologne to develop a concept in the first stage. (author)

  2. Effect of phantom size and composition on neutron dosemeter reading

    International Nuclear Information System (INIS)

    McDonald, J.C.; Tanner, J.E.; Stewart, R.D.; Michel, R.; Murphy, M.K.; Traub, R.J.

    1995-01-01

    Unmoderated and D 2 O-moderated 252 Cf neutron sources were used to irradiate several types of personal neutron dosemeters. The dosemeters were irradiated on polymethylmethacrylate (PMMA) phantoms with frontal dimensions of 40 x 40 cm 2 and 30 x 30 cm 2 ; both phantoms were 15 cm thick. Monte Carlo computer calculations of the neutron spectra and the ratios of dose equivalents at the surfaces of these phantoms were performed using the MCNP computer code. Additional calculations were performed for a 241 Am-Be neutron source and for phantoms composed of International Commission on Radiation Units and Measurements (ICRU) tissue and of water; the water phantom used the design specified recently by the International Organization for Standardization (ISO). The calculations indicated negligible differences in the effects that either of the PMMA phantoms produced on the neutron energy spectra studied. However, the dose equivalent at the surface of the 30 x 30 x 15 cm 3 PMMA phantom differed from the dose equivalents at the surfaces of the water phantom and the ICRU tissue phantom by about 4%. Dosemeters irradiated on the two different sized PMMA phantoms, using unmoderated and D 2 O moderated 252 Cf neutron sources, gave nearly identical readings. All of the phantoms had similar effects on the neutron spectra, producing additional low energy neutrons. It was concluded that either size of PMMA phantom could be used for the irradiations required by the US dosimetry accreditation programmes. (author)

  3. 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)

  4. NUCLEAR HEATING IN LIF DOSEMETERS IN A FUSION NEUTRON FIELD, TRIAL OF DIRECT COMPARISON OF EXPERIMENTAL AND SIMULATED RESULTS.

    Science.gov (United States)

    Pohorecki, Wladyslaw; Obryk, Barbara

    2017-09-29

    The results of nuclear heating measured by means of thermoluminescent dosemeters (TLD-LiF) in a Cu block irradiated by 14 MeV neutrons are presented. The integral Cu experiment relevant for verification of copper nuclear data at neutron energies characteristic for fusion facilities was performed in the ENEA FNG Laboratory at Frascati. Five types of TLDs were used: highly photon sensitive LiF:Mg,Cu,P (MCP-N), 7LiF:Mg,Cu,P (MCP-7) and standard, lower sensitivity LiF:Mg,Ti (MTS-N), 7LiF:Mg,Ti (MTS-7) and 6LiF:Mg,Ti (MTS-6). Calibration of the detectors was performed with gamma rays in terms of air-kerma (10 mGy of 137Cs air-kerma). Nuclear heating in the Cu block was also calculated with the use of MCNP transport code Nuclear heating in Cu and air in TLD's positions was calculated as well. The nuclear heating contribution from all simulated by MCNP6 code particles including protons, deuterons, alphas tritons and heavier ions produced by the neutron interactions were calculated. A trial of the direct comparison between experimental results and results of simulation was performed. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. 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)

  6. On the calibration of radiotherapy dosemeters in Australia

    International Nuclear Information System (INIS)

    Huntley, R.; Kotler, L.; Webb, D.

    2000-01-01

    Full text: Dosemeters for external beam radiotherapy are calibrated in Australia by ARPANSA, against the national primary standards of exposure and absorbed dose. The primary standards are free air chambers for exposure at low and medium energy X-rays, a graphite cavity chamber for exposure at 60 Co, and a graphite calorimeter for absorbed dose at 60 Co and high energy (MV) X -rays. Radiotherapy dosemeters are calibrated against these standards using a well documented formalism to provide calibration factors suitable for use with dosimetry protocols. A dosemeter usually comprises an ionization chamber connected to an independent electrometer. These are calibrated separately if possible. A combined calibration factor is reported together with the electrometer calibration factor (sensitivity). The dosimetry protocol used in radiotherapy centres in Australia and New Zealand is currently the simplified version of the IAEA TRS277 protocol, published by the New Zealand NRL and recommended by the ACPSEM. This protocol requires the use of an exposure or air kerma calibration factor at 60 Co (Nx or Nk) to evaluate the absorbed dose to air calibration factor N D . The chamber is then placed in a water phantom with its centre displaced from the reference point by p eff . ARPANSA can also supply calibration factors in absorbed dose to water (N D,w ), as required as input to the new IAEA CoP. If an absorbed dose to water calibration factor is used by the radiotherapy centre, the chamber should be placed with its centre at the reference point in the water phantom. ARPANSA has for some years coordinated the participation of Australian radiotherapy centres in the IAEA TLD Quality Audit service. Note that this service does not represent a calibration and should not be referred to as such. The only calibration is that provided by ARPANSA for a reference dosemeter at each radiotherapy centre. As soon as the ANSTO SSDL is operational, calibrations of reference dosemeters will also be

  7. Thermoluminescent characterization of thin films of aluminium oxide submitted to beta and gamma radiation; Caracterizacion termoluminiscente de peliculas delgadas de oxido de aluminio sometidas a radiacion beta y gamma

    Energy Technology Data Exchange (ETDEWEB)

    Villagran, E.; Escobar A, L.; Camps, E.; Gonzalez, P.R.; Martinez A, L. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    By mean of the laser ablation technique, thin films of aluminium oxide have been deposited on kapton substrates. These films present thermoluminescent response (Tl) when they are exposed to beta and gamma radiation. The brilliance curves show two peaks between 112 C and 180 C. A dose-response relationship study was realized and the Tl kinetic parameters were determined using the computerized deconvolution of the brilliance curve (CGCD). The thin films of aluminium oxide have potential applications as ultra.thin radiation dosemeters. (Author)

  8. Intermediate neutron detection by thermoluminescence

    International Nuclear Information System (INIS)

    Santos, E.N. dos; Muccillo, R.

    1979-01-01

    Thermoluminescent (TL) studies were carried out in cold-pressed CaSO 4 :Dy + Dy 2 O 3 + KCl and CaF 2 + Dy 2 O 3 + KCl polycrystalline samples exposed to mixed neutron-gamma fields, for the detection of intermediate neutrons which is based on the evaluation of the TL signal of the specimens stored for 24 hours after being exposed to a mixed neutron-gamma field and thermally annealed to erase the total radiation-induced TL. The addition of Dy 2 O 3 to CaSO 4 :Dy in the proportion 1:2 increased the neutron response by a factor of 160 relative to that of CaSO 4 :Dy. 180 mg of CaSO 4 :Dy + Dy 2 O 3 + KCl in the proportion 2:1:3 showed to be an appropriate detector of intermediate neutrons; the minimum detectable fluence was estimated to be 3.5 x 10 5 neutrons/cm 2 . (Author) [pt

  9. New thermoluminescence techniques for mineral exploration

    Energy Technology Data Exchange (ETDEWEB)

    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. (DLC)

  10. 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)

  11. Dose profile for electron beams obtained with CaSO{sub 4}:Ce,Eu thermoluminescent dosimeters; Perfil de dose de feixes de eletrons obtidos com dosimetros termoluminescentes de CaSO{sub 4}:Ce,Eu

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Maira G.; Rodrigues, Leticia L.C., E-mail: mgnunes@ipen.br [Instituto de Pesquisas Energerticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-12-15

    The calcium sulphate activated with cerium and europium (CaSO{sub 4}:Ce,Eu) thermoluminescent dosimeters (TLD) recently developed at Nuclear and Energy Research Institute as well as the calcium sulphate activated with dysprosium (CaSO{sub 4}: Dy) and lithium fluoride activated with magnesium and titanium, (LiF:Mg,Ti; TLD-100) TLDs, with long term applications in dosimetry and considered as standards, were used to obtain the dose profile for 3.43, 5.48, 8.27 and 11.67 MeV electron beams generated by a linear accelerator Clinac 2100-C (Varian) in the reference conditions defined by the TRS-398 code of practice. The routine dosimetry of the electron beams, performed with a calibrated ionization chamber, ensures that the electron beams fulfill the requirements of flatness and symmetry established in this code of practice. Thus, as the TRS-398 Code of Practice requirements are fulfilled by the measurements performed with the new TLD type, CaSO{sub 4}:Ce,Eu may be applied in clinical dosimetry of high energy electron beams. (author)

  12. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    International Nuclear Information System (INIS)

    Yuen, P.S.; Freedman, N.O.; Frketich, G.; Rotunda, J.

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of light exposure. Test results, as detailed in this paper, show that this extremity dosemeter meets the ISO draft standards requirement in all categories except residue. Its 2nd reading residue (7%) is much higher than other TLD materials (0.2%). However, it was found that an annealing in the oven at 240 o C for 10 min prior to the 2nd reading reduces the residue to 0.4%, comparable to that of other TLD materials. The greatest advantage of this dosemeter is that it can measure beta skin dose accurately over a wide range of beta energies. (author)

  13. Evaluation of Bicron NE MCP DXT-RAD Passive Extremity Dosemeter

    International Nuclear Information System (INIS)

    Yuen, P.S.; Freedman, N.O.; Frketich, G.; Rotunda, J.

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of light exposure. Test results, as detailed in this paper, show that this extremity dosemeter meets the ISO draft standards requirement in all categories except residue. Its 2nd reading residue (7%) is much higher than other TLD materials (0.2%). However, it was found that an annealing in the oven at 240 deg C for 10 min prior to the 2nd reading reduces the residue to 0.4%, comparable to that of other TLD materials. The greatest advantage of this dosemeter is that it can measure beta skin dose accurately over a wide range of beta energies. (author)

  14. Development of radiophotometric dosemeters with high sensitivity using plastic scintillators as a light intensifier

    International Nuclear Information System (INIS)

    Mesquita, C.H. de; Hamada, M.M.

    1987-01-01

    Rectangular plates of plastic scintillators are developed and their effect as light converter evaluated, when used as film-holder in conventional photography dosemeters. In this dosemeter, the radiation that not interacts in the photographic film can be detected by light photons generation in the plastic scintillators, sensitizing the film. (C.G.C.) [pt

  15. Systematic processing of the external individual monitoring data obtained by photographic film and capacitor dosemeters

    International Nuclear Information System (INIS)

    Krueger, F.; Shtuk, D.

    1983-01-01

    Individual radiation load measurements have been carried out both with photographic film and capacitor type dosemeters (CD). Systematic statistics methods were applied for the obtained data processing. The CD data were shown to exceed those measured with the film dosemeters. Specific features of the CD application are revealed that should be taken into account in practice [ru

  16. A method for evaluating personal dosemeters in workplace with neutron fields.

    Science.gov (United States)

    de Freitas Nascimento, Luana; Cauwels, Vanessa; Vanhavere, Filip

    2012-04-01

    Passive detectors, as albedo or track-etch, still dominate the field of neutron personal dosimetry, mainly due to their low-cost, high-reliability and elevated throughput. However, the recent appearance in the market of electronic personal dosemeters for neutrons presents a new option for personal dosimetry. In addition to passive detectors, electronic personal dosemeters necessitate correction factors, concerning their energy and angular response dependencies. This paper reports on the results of a method to evaluate personal dosemeters for workplace where neutrons are present. The approach here uses few instruments and does not necessitate a large mathematical workload. Qualitative information on the neutron energy spectrum is acquired using a simple spectrometer (Nprobe), reference values for H*(10) are derived from measurements with ambient detectors (Studsvik, Berthold and Harwell) and angular information is measured using personal dosemeters (electronic and bubbles dosemeters) disposed in different orientations on a slab phantom.

  17. 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.

  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. Aluminium nitrate ceramics: A potential UV dosemeter material

    DEFF Research Database (Denmark)

    Trinkler, L.; Bøtter-Jensen, L.; Berzina, B.

    2002-01-01

    The ceramic material AIN-Y2O3 is proposed as a potential ultraviolet radiation (UVR) dosemeter using optically stimulated luminescence (OSL) and thermally stimulated luminescence (TL). Experimental studies have shown that AIN ceramics exhibit attractive characteristics suitable for practical UV...... dosimetry applications. The features are: (1) the spectral sensitivity covers the 200-350 nm range, in the UV-B region it is similar to that of human skin: (2) the angular dependence of the incident radiation follows the cosine law; (3) high yields of both UVR-induced OSL and TL signals compared to those...

  20. Household and workplace chemicals as retrospective luminescence dosemeters

    DEFF Research Database (Denmark)

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

    2002-01-01

    In the development of techniques for the retrospective assessment of the close absorbed by communities living and working adjacent to the site of a nuclear accident, attention has concentrated on the use Of natural minerals such as quartz and feldspar as dosemeters. These minerals are widely found...... in household earthenware and almost all types of bricks and concrete. Their main disadvantages are variable and often low sensitivity. and the possibility of a comparatively large natural dose prior to the accident, depending on the age of the building and the type of building material. However...

  1. New KID dosemeter for measurement of cosmic dosimetry

    International Nuclear Information System (INIS)

    Peksova, D.; Kakona, M.; Krist, P.; Kocur, Z.; Larina, K. V.; Ploc, O.

    2018-01-01

    The KID dosemeter is a small semiconductor low-power detector developed for common use. The current design is special designed after measuring cosmic rays on aircraft decks. The design concept is the same world-class devices Internet of Things (IoT). As a detection element detector were tested three variants a) PIN HAMAMATSU S2744-09 photodiode, b) 9 parallel Vishay photodiodes TEMD5080X01, c) 16 Vishay photodiode TEMD5080X01 again in parallel connection. All variants are silicon PIN photodiode. (authors)

  2. Alpha particle and proton relative thermoluminescence efficiencies in LiF:Mg, Cu, P:is track structure theory up to the task?

    International Nuclear Information System (INIS)

    Horowitz, Y. S.; Siboni, D.; Oster, L.; Livingstone, J.; Guatelli, S.; Rosenfeld, A.; Emfietzoglou, D.; Bilski, P.; Obryk, B.

    2008-01-01

    Low-energy alpha particle and proton heavy charged particle (HCP) relative thermoluminescence (TL) efficiencies are calculated for the major dosimetric glow peak in LiF:Mg, Cu, P (MCP-N) in the framework of track structure theory (TST). The calculations employ previously published TRIPOS-E Monte Carlo track segment values of the radial dose in condensed phase LiF calculated at the Instituto National de Investigaciones Nucleares (Mexico) and experimentally measured normalised 60 Co gamma-induced TL dose-response functions, f(D), carried out at the Inst. of Nuclear Physics (Poland). The motivation for the calculations is to test the validity of TST in a TL system in which f(D) is not supra-linear (f(D) >1) and is not significantly dependent on photon energy contrary to the behaviour of the dose-response of composite peak 5 in the glow curve of LiF:Mg, Ti (TLD-100). The calculated HCP relative efficiencies in LiF:MCP-N are 23-87 % lower than the experimentally measured values, indicating a weakness in the major premise of TST which exclusively relates HCP effects to the radiation action of the secondary electrons liberated by the HCP slowing down. However, an analysis of the uncertainties involved in the TST calculations and experiments (i.e. experimental measurement of f(D) at high levels of dose, sample light self-absorption and accuracy in the estimation of D R, especially towards the end of the HCP track) indicate that these may be too large to enable a definite conclusion. More accurate estimation of sample light self-absorption, improved measurements of f(D) and full-track Monte Carlo calculations of D R incorporating improvements of the low-energy electron transport are indicated in order to reduce uncertainties and enable a final conclusion. (authors)

  3. 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.

  4. Thermoluminescence of zircon : a kinetic model

    NARCIS (Netherlands)

    Turkin, AA; van Es, HJ; Vainshtein, DI; den Hartog, HW

    2003-01-01

    The mineral zircon, ZrSiO4, belongs to a class of promising materials for geochronometry by means of thermoluminescence (TL) dating. The development of a reliable and reproducible method for TL dating with zircon requires detailed knowledge of the processes taking place during exposure to ionizing

  5. Mineral zircon : A novel thermoluminescence geochronometer

    NARCIS (Netherlands)

    Vanes, H.J.; Vainshtein, DI; De Meijer, RJ; Den Hartog, HW; Donoghue, JF; Rozendaal, A

    2002-01-01

    Mineral zircon contains trace amounts (typically 10-1000 ppm) of the alpha-emitters uranium and thorium, which irradiate this mineral internally. This outstanding feature of zircon turns out to be extremely useful when this mineral is applied as a thermoluminescence (TL) dating medium, because the

  6. 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.

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

    Indian Academy of Sciences (India)

    The thermoluminescence (TL) properties of calcium aluminate (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 about 4 kGy of ...

  8. Thermoluminescence studies - application to earth sciences

    International Nuclear Information System (INIS)

    Sankaran, A.V.; Sunta, C.M.; Nambi, K.S.V.; Kaul, I.K.; Bhattacharya, A.K.

    1979-01-01

    Studies on the applications of thermoluminescence in the fields of petrogenesis, rock tectonics, ore prospecting, paleoclimatology, geological dating of mineralisation events, igneous activity, sediments and metamict minerals, sediment growth rate, stratigraphic correlation and diagenetic history are reviewed. (M.G.B.)

  9. Photoluminescence, trap states and thermoluminescence decay ...

    Indian Academy of Sciences (India)

    ... solid-state reaction. The Fourier transform infrared (FT–IR) spectra confirmed the proper preparation of the sample. The prepared phosphors were characterized using photoluminescence excitation and emission spectra. Prominent green colour emission was obtained under ultraviolet excitation. The thermoluminescence ...

  10. Thermoluminescence dating of Hawaiian basalt

    Science.gov (United States)

    May, Rodd James

    1979-01-01

    The thermoluminescence (TL) properties of plagioclase separates from 11 independently dated alkalic basalts 4,500 years to 3.3 million years old and 17 tholeiitic basalts 16 years to 450,000 years old from the Hawaiian Islands were investigated for the purpose of developing a TL dating method for young volcanic rocks. Ratios of natural to artificial TL intensity, when normalized for natural radiation dose rates, were used to quantify the thermoluminescence response of individual samples for age-determination purposes. The TL ratios for the alkalic basalt plagioclase were found to increase with age at a predictable exponential rate that permits the use of the equation for the best-fit line through a plot of the TL ratios relative to known age as a TL age equation. The equation is applicable to rocks ranging in composition from basaltic andesite to trachyte over the age range from about 2,000 to at least 250,000 years before present (B.P.). The TL ages for samples older than 50,000 years have a calculated precision of less than :t 10 percent and a potential estimated accuracy relative to potassium-argon ages of approximately :t 10 percent. An attempt to develop a similar dating curve for the tholeiitic basalts was not as successful, primarily because the dose rates are on the average lower than those for the alkalic basalts by a factor of 6, resulting in lower TL intensities in the tholeiitic basalts for samples of equivalent age, and also because the age distribution of dated material is inadequate. The basic TL properties of the plagioclase from the two rock types are similar, however, and TL dating of tholeiitic basalts should eventually be feasible over the age range 10,000 to at least 200,000 years B.P. The average composition of the plagioclase separates from the alkalic basalts ranges from oligoclase to andesine; compositional variations within this range have no apparent effect on the TL ratios. The average composition of the plagioclase from the tholeiitic

  11. A study of the irradiation temperature coefficient for L-alanine and DL-alanine dosemeters

    International Nuclear Information System (INIS)

    Desrosiers, M. F.; Lin, M.; Cooper, S. L.; Cui, Y.; Chen, K.

    2006-01-01

    Alanine dosimetry is now well established both as a reference and routine dosemeter for industrial irradiation processing. Accurate dosimetry under the relatively harsh conditions of industrial processing requires a characterisation of the parameters that influence the dosemeter response. The temperature of the dosemeter during irradiation is a difficult quantity to measure so that the accuracy of the temperature coefficient that governs the dosemeter response becomes a critical factor. Numerous publications have reported temperature coefficients for several types of alanine dosemeters. The observed differences in the measured values were commonly attributed to the differences in the polymer binder or the experimental design of the measurement. However, the data demonstrated a consistent difference in the temperature coefficients between L-alanine and DL-alanine. Since there were no commonalities in the dosemeter composition or the measurement methods applied, a clear conclusion is not possible. To resolve this issue, the two isomeric forms of alanine dosemeters were prepared and irradiated in an identical manner. The results indicated that the DL-alanine temperature coefficient is more than 50% higher than the L-alanine temperature coefficient. (authors)

  12. Understanding differences in dose-equivalents reported by passive and electronic personal dosemeters

    International Nuclear Information System (INIS)

    Perks, Christopher A.; Burgess, Peter; Smith, David; Salasky, Mark; Yahnke, Cliff

    2008-01-01

    Full text: In a number of challenging environments, clients occasionally double badge with electronic personal dosemeters (EPDs) to ensure day-to-day management of their employees personal dose-equivalent while using passive (in our case Luxel or InLight) dosemeters for monthly monitoring for approved results for dose record keeping. In some cases there have been significant differences in the cumulative doses recorded by the EPDs and the passive dosemeters. In these circumstances the passive dosemeters usually report a higher dose than the EPD by up to a factor of two, though more commonly 1.3. In this paper we describe the differences seen between EPD and passive dosemeters (in a number of countries). We then examine the possible causes for such discrepancies by comparison with published response function data available for the EPDs and Landauer dosemeters. We have undertaken a number of experiments comparing directly a number of EPDs and passive dosemeter response to a variety of energy and complex angular geometries where the two types of dosimeter have been exposed at the same time. Recommendations will be made on the appropriate use of double badging in difficult environments and interpretation of the results. (author)

  13. Measurements of environmental gamma-ray spectra using a multi-element TL dosemeter

    International Nuclear Information System (INIS)

    Furuta, Sadaaki; Boetter-Jensen, L.; Nielsen, S.P.

    1986-12-01

    A method to estimate the energy distribution and dose of environmental gamma radiation was developed using a multielement TL dosemeter. Experimentally obtained energy responses from a multi-element TL dosemeter with different kinds of filters were used to calculate the energy distribution and related dose by the SAND-II computer code. The code was originally developed to estimate the neutron flux using a multiple foil activation method. Measurements were made at several locations with the multi-element TL dosemeter and comparisons were made with results from a NaI(Tl) scintillation detector and a high-pressure ionization chamber. (author)

  14. 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)

  15. Calibration of dosemeters used in mammography with different X ray qualities: EUROMET Project No. 526

    Czech Academy of Sciences Publication Activity Database

    Witzani, J.; Bjerke, H.; Bochud, F.; Csete, I.; Denoziere, M.; de Vries, W.; Ennow, K.; Grindborg, J.; Hourdakis, C.; Kosunen, A.; Kramer, H. M.; Pernička, František; Sander, T.

    2004-01-01

    Roč. 108, č. 1 (2004), s. 33-45 ISSN 0144-8420 Institutional research plan: CEZ:AV0Z1048901 Keywords : calibration * dosemeters * mammography Subject RIV: FD - Oncology ; Hematology Impact factor: 0.617, year: 2003

  16. Personal neutron dosemeter of the Czech Republic: Review of basic properties, results of recent tests

    Czech Academy of Sciences Publication Activity Database

    Trousil, J.; Spurný, František; Plichta, J.

    2006-01-01

    Roč. 14, 7/8 (2006), s. 246-253 ISSN 1210-7085 Institutional research plan: CEZ:AV0Z10480505 Keywords : detectors * dosemeters * personal dosimetry Subject RIV: DN - Health Impact of the Environment Quality

  17. Sensitivity of a LR-115 based radon dosemeter

    CERN Document Server

    Bagnoli, F; Bucci, S

    1999-01-01

    The first results of a study on the sensitivity of a LR-115 based radon dosemeter as a function of the absorber thickness are presented. The theoretical sensitivity was analytically calculated considering a constant detector response to alpha particles within a given energy range and up to a critical angle of incidence. The results are presented in two extreme situations: i) both radon and its decay products uniformly distributed in the chamber volume; ii) radon decay products uniformly deposited on the chamber walls. The agreement with the experimental curve shape appears better in the former case, suggesting that either the parameter values of the model could be different from the chosen values, or the model was too simplified.

  18. 1983 ORNL intercomparison of personnel neutron and gamma dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Swaja, R.E.; Sims, C.S.; Greene, R.T.

    1985-01-01

    The Ninth Personnel Dosimetry Intercomparison Study was conducted during April 19-21, 1983, at the Oak Ridge National Laboratory. Dosemeters from 33 participating agencies were mounted on water-filled polyethylene elliptical phantoms and exposed to a range of low-level dose equivalents (0.02-0.45 mSv gamma and 0.49-11.14 mSv neutron) which could be encountered during routine personnel monitoring in mixed radiation fields. The Health Physics Research Reactor served as the radiation source for six separate exposures which used four different shield conditions: unshielded and shielded with steel, steel/concrete, and concrete. Results of the neutron measurements indicate that it is not unusual for dose equivalent estimates made under the same conditions by different agencies to differ by more than a factor of 2. Albedo systems, which were the most popular neutron monitors in this study, provided the most accurate results with CR-39 recoil track being least accurate. Track and film neutron systems exhibited problems providing measurable indication of neutron exposure at dose equivalents of about 0.50 mSv. Gamma measurements showed that TLD and film systems generally overestimated dose equivalents in the mixed radiation fields with film exhibiting significant problems providing measurable indication of gamma exposure at dose equivalents lower than about 0.15 mSv. Under the conditions of this study in which exposures were carefully controlled and participants had information concerning exposure conditions and incident spectra prior to dosemeter analysis, only slightly more than half of all neutron and gamma dose equivalent estimates met regulatory accuracy standards relative to reference values. These results indicate that continued improvement of mixed-field personnel dosimetry is required by many participating organizations. 15 references, 30 tables.

  19. Estimate of the exposition to the ionizing radiation of the medical veterinarians and its assistants in radiology examinations veterinary medicine

    International Nuclear Information System (INIS)

    Lima, G.; Braz, D.; Lopez, R.; Mauricia, C.; Barroso, R.

    2006-01-01

    The absorbed ionizing radiation outside of the permissible limits, can cause biological damages e, therefore it must necessarily be monitored. The dosimetry thermoluminescent is a technique very used to detect expositions in operators, therefore they are sensible crystals the ionizing radiation and allows to evaluate if the dose of radiation is or not below of the restriction levels. In scientific literature many information do not exist on the exposition of a medical veterinarian, with this do not have many data of the individual monitoring of these workers, becoming the work it important for posterior studies. Ahead of this, it was carried through measured of the doses, using the thermoluminescence dosemeters LiF: Mg, Cu, P (TLD-100 H) in the position of the crystalline lens, thyroid, hand and thorax, in three clinics of radiology veterinary medicine, different, having the objective to determine the dose distribution that the workers of radiology veterinary medicine are submitted in one day of work. (authors)

  20. Estimate of the exposition to the ionizing radiation of the medical veterinarians and its assistants in radiology examinations veterinary medicine

    Energy Technology Data Exchange (ETDEWEB)

    Lima, G.; Braz, D.; Lopez, R. [Rio de Janeiro Univ. Federal, COPPE (Brazil); Mauricia, C. [Rio de Janeiro Univ. Federal, Instituto de Radioprotecao e Dosimetria (Brazil); Barroso, R. [Rio de Janeiro Univ. Federal, Universidade Estadual do Rio de Janeiro (Brazil)

    2006-07-01

    The absorbed ionizing radiation outside of the permissible limits, can cause biological damages e, therefore it must necessarily be monitored. The dosimetry thermoluminescent is a technique very used to detect expositions in operatorserefore they are sensible crystals the ionizing radiation and allows to evaluate if the dose of radiation is or not below of the restriction levels. In scientific literature many information do not exist on the exposition of a medical veterinarian, with this do not have many data of the individual monitoring of these workers, becoming the work it important for posterior studies. Ahead of this, it was carried through measured of the doses, using the thermoluminescence dosemeters LiF: Mg, Cu, P (TLD-100 H) in the position of the crystalline lens, thyroid, hand and thorax, in three clinics of radiology veterinary medicine, different, having the objective to determine the dose distribution that the workers of radiology veterinary medicine are submitted in one day of work. (authors)

  1. 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.)

  2. Determination of isodose curves in Radiotherapy using an Alanine/ESR dosemeter

    International Nuclear Information System (INIS)

    Chen, F.; Baffa, O.; Graeff, C.F.O.

    1998-01-01

    It was studied the possible use of an Alanine/ESR dosemeter in the isodose curves mapping in normal treatments of Radiotherapy. It was manufactured a lot of 150 dosemeters with base in a mixture of D-L Alanine dust (80 %) and paraffin (20 %). Each dosemeter has 4.7 mm diameter and 12 mm length. A group of 100 dosemeters of the lot were arranged inside 50 holes of the slice 25 of the phantom Rando Man. The phantom irradiation was realized in two opposed projections (AP and PA) in Co-60 equipment. A group of 15 dosemeters was take of the same lot for obtaining the calibration curve in a 1-20 Gy range. After irradiation the signal of each dosemeter was measured in an ESR spectrometer operating in the X-band (∼ 9.5 GHz) and the wideness of Alanine ESR spectra central line was correlated with the radiation dose. The wideness dose calibration curve resulted linear with a correlation coefficient 0.9996. The isodose curves obtained show a profile enough similar at comparing with the theoretical curves. (Author)

  3. Individual monitoring with official electronic dosemeters in Germany - concepts and reality

    International Nuclear Information System (INIS)

    Martini, E.; Wahl, W.; Huebner, S.; Freynhagen, D.; Staemmler, M.

    2005-01-01

    Full text: Active (electronic) personal dosemeters (APD) are radiometers, which are equipped as active or passive dosimeters. They can directly indicate a dose rate and/or the dose integrated during a certain period (direct-indicating, active electronic personal dosemeters mentioned) or only over a separate reader (direct-selectable, passive electronic personal dosemeters mentioned). A concept is presented for the use of passive or active electronic personal dosemeters in Germany as official dosemeters, e.g. in hospitals. The concept features a net-based approach for secure data communication between readers for passive and active electronic personal dosemeters und the official personal dosimetry monitoring service(s), taking the German policies (StrISchV und RoeV in hospitals) into account. The net-based solution includes a processor controlled interface via TCP/IP connected to the dosimetry reader(s), und reader interfaces, an official interim data bank and all the necessary equipment such as PC, Raid-configuration, USV support, network connection and further details. Investigations have been started to achieve highest-level data manipulation security, data completeness und data correctness. (author)

  4. 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)

  5. Type testing of a head band dosemeter for measuring eye lens dose in terms of H(P)(3).

    Science.gov (United States)

    Gilvin, P J; Baker, S T; Gibbens, N J; Roberts, G H; Tanner, R J; Eakins, J S; Hager, L G; Daniels, T J

    2013-12-01

    A new head band dosemeter, for the measurement of eye lens dose in terms of Hp(3), has been type tested by Public Health England's Centre for Radiation, Environmental and Chemical Hazards [formerly part of the UK Health Protection Agency (HPA)]. The type tests were based on the International Standard ISO 12794, drawing also upon earlier work at HPA. The results show that, unlike many existing dosemeters, the new head band dosemeter correctly measures Hp(3) for beta radiations as well as photons.

  6. Thermoluminescent (Tl) dosimetry of slow-neutron fields at radiotherapy dose level

    International Nuclear Information System (INIS)

    Gambarini, G.

    2003-01-01

    The dosimetry for radiotherapy involving neutrons is very complicated, owing to the complexity of secondary radiation components, whose contributions to the total absorbed dose have to be discriminated, owing to the different radiobiological effects. In order to separate thermal neutrons and photons, LiF dosimeters are mostly utilized. containing different percentage of Li, like as TLD-700, TLD-100 and TLD-600, but many problems arise. In the response of TLD-700 exposed to neutron-gamma mixed fields with high neutron flux, the contribution of thermal neutrons to the Tl emission is high. Moreover. TLD-100 and TLD-600 may undergo radiation damage, and great care has to be taken in order to obtain reliable results. Other TLDs showing lower sensitivity to neutrons are proposed and experimented for such high-flux neutron fields. The faced problems and various proposed solutions are here described. (Author)

  7. Performance of Harshaw 6600 thermo-luminescence dosimeter (TLD)

    African Journals Online (AJOL)

    Performance of Harshaw 6600 thermo-luminescence dosimeter (TLD) system for personal monitoring. ... Fading of 19 % of thermo-luminescence (TL) readout was observed in 90 days when TLD chips were stored at room temperature (~ 27º C). The TL sensitivities of chips in three holder types were close to that for Cs-137 ...

  8. Thermoluminescence, luminescence optically stimulated and creation of defects in alkaline halogenides contaminated with Europium; Termoluminiscencia, luminiscencia opticamente estimulada y creacion de defectos en halogenuros alcalinos contaminados con Europio

    Energy Technology Data Exchange (ETDEWEB)

    Barboza F, M. [Centro de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, 83190 Hermosillo, Sonora (Mexico)

    1999-07-01

    The alkaline halogenides have been subject matter of investigations related with the search of sensor materials for X-ray bidimensional images or optical memories. The understanding of the damage formation processes generated by ionizing and non-ionizing radiations is important for the correct design of devices that working as detectors and dosemeters of both type of radiations. In this work we present the investigation results related with the defects produced by the ionizing radiation type X and ultraviolet light in the range of 200-360 nm in crystals of KCl: Eu{sup 2+} and KBr:Eu{sup 2+}. It is examined the thermoluminescence and luminescence spectra with the purpose of identifying the exciton processes, owing to the excitation of the halogenide ions in which the primary defects correspond to the F and H centers. It has been found that the 400-600 nm emission is associated with the luminescence type that in his turn can be associated with autotrapped excitons perturbed by the impurity. On the other hand, it is examined the emission spectra of the luminescence optically stimulated in crystals of KBr: Eu{sup 2+} and KCl: Eu{sup 2+} finding too that such materials would be used as optical memories susceptible of to store information, and through of photostimulation to read this. It was determined that the F centers participate in the luminescence optically stimulated in these crystals, as well as too in the recombination processes responsible by the thermoluminescent emission. (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. Dating of the archaeological site 'El Tigre' by the thermoluminescent method; Fechamiento del sitio arqueologico 'El Tigre' por el metodo de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Portilla, R. De la [ENAH, Periferico Sur y Zapote, 14030 Mexico D.F. (Mexico); Gonzalez, P.R.; Mendoza, D. [ININ, 52750 La Marquesa, Ocoyoacac, Estado de Mexico (Mexico); Vargas, E. [Instituto de Investigaciones Antropologicas, UNAM, 04510 Mexico D.F. (Mexico); Ramirez, A. [Instituto de Geofisica, UNAM, 04510 Mexico D.F. (Mexico)

    2007-07-01

    Full text: The dating of pre hispanic pottery, is supported by techniques such as stratigraphy, typology, in physical and chemical procedures, as the analysis of {sup 14}C and the thermoluminescence (TL). The last one permits us obtain absolute dating of archaeological pottery with an acceptable precision. In this work we apply the applied the thermoluminescent technique to verify the age of the Pre-Classic and Classic Terminal periods proposed for the archaeological site 'El Tigre', Campeche. The samples were obtained during a work period and the radiation of the ground of background (emitted by the ground), as well as the contribution of the cosmic radiation was measured with thermoluminescent dosemeters of LiF: Mg,Cu,P + PTFE, put in the sample zone. The preliminary results indicate that not all the analyzed samples can be dated. The viability of the dating of the samples is discussed based on the fact and function of the presence of certain crystalline phases such as calcite and quartz. The discussion is complemented emphsizing the importance of handling the conditions of handling of samples. (Author)

  11. 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)

  12. Thermoluminescence sensitivity of ulexite after UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Topaksu, M., E-mail: mats@cu.edu.tr [Cukurova University, Arts-Sciences Faculty, Physics Department, 01330 Adana (Turkey); CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Correcher, V. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Garcia-Guinea, J. [Museo Nacional de Ciencias Naturales, (CSIC), C/José Gutiérrez Abascal 2, 28006 Madrid (Spain)

    2015-04-15

    Highlights: •UV-induced thermoluminescence emission of Turkish ulexite was studied. •There are three groups of components. •The UV exposures were performed at controlled temperatures. -- Abstract: The effects of UV radiation on the thermoluminescence (TL) properties of natural materials, in contrast to synthetic materials, have been scarcely studied. We report on the UV-induced thermoluminescence emission of a Turkish ulexite (NaCaB{sub 5}O{sub 6}(OH){sub 6}·5H{sub 2}O) that displays very complex TL glow curves, with at least three groups of components peaked at 130–140 °C, 240 °C and, 340 °C, wherein the last group is weaker. Such emission could be associated with structural changes in the lattice as well as alkali self-diffusion processes. The UV exposure performed at controlled temperatures (at room temperature (RT), 50 °C and 100 °C) produced a (i) different evolutions of the intensities of each maximum, which are directly related to the controlled thermal treatment; (ii) different intensity ratios among the groups of components; (iii) different activation energies (E{sub a}) (1.13 eV for RT, 0.99 eV for 50 °C and 0.49 eV for 100 °C) calculated using the initial rise method; and (iv) similar scattering values (12.4%, 8.2% and 12.8%), which were not a function of the controlled temperature. The thermal stability tests conducted on this borate at different temperatures, based on the T{sub stop} protocol, confirm the presence of a continuum in the distribution of the trap system with progressively increasing E{sub a} (from 0.60 to 0.90 eV)

  13. Reactor Gamma Heat Measurements with Calorimeters and Thermoluminescence Dosimeters

    DEFF Research Database (Denmark)

    Haack, Karsten; Majborn, Benny

    1973-01-01

    Intercomparison measurements of reactor γ-ray heating were carried out with calorimeters and thermoluminescence dosimeters. Within the measurement uncertainties the two methods yield coincident results. In the actual measurement range thermoluminescence dosimeters are less accurate than calorimet......Intercomparison measurements of reactor γ-ray heating were carried out with calorimeters and thermoluminescence dosimeters. Within the measurement uncertainties the two methods yield coincident results. In the actual measurement range thermoluminescence dosimeters are less accurate than...... calorimeters, but possess advantages such as a small probe size and the possibility of making simultaneous measurements at many different positions. Hence, thermoluminescence dosimeters may constitute a valuable supplement to calorimeters for reactor γ-ray heating measurements....

  14. Thermoluminescent response of LaAlO3:Pr

    International Nuclear Information System (INIS)

    Morales H, A.; Zarate M, J.; Azorin N, J.; Rivera M, T.

    2015-10-01

    In this study, the thermoluminescence response of doped lanthanum aluminate (LaAlO 3 ) with praseodymium ion (Pr) obtained by the Pechini method and drying by the spraying technique Spry Dryer was studied. The obtained powders were analyzed structurally by the X-ray diffraction technique; the morphological characterization was by the scanning electron microscopy technique. The obtained powders at 800 degrees C presented crystallinity and showed a Rhombohedral crystal structure, this phase was observed by X-ray diffraction patterns. Thermoluminescence response of LaAlO 3 :Pr showed a brightness curve with a peak centered at 157 degrees C. The sensitivity of the doped samples was improved about 90 times in comparison with the undoped sample. Thermoluminescence response in function of the wavelength showed a maximum at 230 nm, reproducibility of thermoluminescence response was ±50%. Also the fading in thermoluminescence response was studied. (Author)

  15. Method of analysis of asbestiform minerals by thermoluminescence

    Science.gov (United States)

    Fisher, Gerald L.; Bradley, Edward W.

    1980-01-01

    A method for the qualitative and quantitative analysis of asbestiform minerals, including the steps of subjecting a sample to be analyzed to the thermoluminescent analysis, annealing the sample, subjecting the sample to ionizing radiation, and subjecting the sample to a second thermoluminescent analysis. Glow curves are derived from the two thermoluminescent analyses and their shapes then compared to established glow curves of known asbestiform minerals to identify the type of asbestiform in the sample. Also, during at least one of the analyses, the thermoluminescent response for each sample is integrated during a linear heating period of the analysis in order to derive the total thermoluminescence per milligram of sample. This total is a measure of the quantity of asbestiform in the sample and may also be used to identify the source of the sample.

  16. 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)

  17. Investigation of thermoluminescent response of K2YF5:Dy3+ crystals for gamma and X radiation fields

    International Nuclear Information System (INIS)

    Silva, E.C.; Nogueira, M.S.; Faria, L.O.; Khaidukov, N.M.

    2005-01-01

    K 2 YF 5 crystals doped with rare earths have been synthesized with 0 to 100% of Dy 3+ ions optically active ions and an investigation was conducted to test its thermoluminescent (TL) response due to function of Dy 3+ concentration and their response in energy. After being irradiated with gamma and X-rays, it was observed that crystals doped with 1.0% of Dy 3+ feature the best response TL. The main dosimetric peak can be decomposed into three secondary TL peaks, centered in 96.4, 104.9 and 130.7 deg C, respectively, showing a good linearity and reproducibility of the dose measurements. The sensitization process seems to improve response TL and TL peak sensitivity increase to 130, 7 deg C at the expense of TL peak to 104, 9 deg C. The linear coefficient sign TL for K 2 Y 0.09 Dy 0.01 F5 is comparable to that of the dosemeter CaSO 4 : Mn, irradiated with gamma radiation source ( 137 Cs) under the same conditions. Energy dependence measurements show that the answer for X-rays with energy of 41.1 keV is more than 30 times the response to Cs-137, when exposed to the same dose. Due to the main peak in low temperature and the TL high reply to low energy fields, the results reported indicate that the K 2 YF 5 crystals doped with Dy 3+ present great potential for radiation dosimetry in X-rays therapy, clinical dosimetry and also for applications in digital thermoluminescent images

  18. Intercomparison program of personal dosemeters in the Argentine Republic

    International Nuclear Information System (INIS)

    Gregori, B.N.; Papadopulos, S.B.; Kunst, J.J.

    1998-01-01

    During 1997, under the auspices of the Nuclear Regulatory Authority (ARN), its was held the third exercise of intercomparison of laboratories of personal dosimetry. The dosemeters were irradiated in X-ray beams ISO quality W60, W110, W200 and gamma sources cesium 137 and cobalt 60. The irradiation were performed kerma free in air and in phantom in order to study the capacity to evaluate both conditions. An extent range of doses (low-high) have been given 0.3 mSv- 20mSv in order to determine the operative performance o each laboratory. Over 19 laboratories of Argentina, participated 13 (65%) and finished the intercomparison 12 (60%) of them. The systems of dosimetry detection were based on film and TLD. During this intercomparison as inquiry about several items related with the laboratories have been made. In this work are shown the individual laboratory results of the intercomparison related with the acceptance curve criteria ICRP 60 and 55. (author)

  19. The SNAC2 area dosemeter - principle, description, utilization

    International Nuclear Information System (INIS)

    Buxerolle, M.; Kurdjian, J.; Colonges, J.C.

    1991-09-01

    In case of criticality accident, the characteristics of the radiation produced (photons and neutrons) must be determined in order to specify the risks to an exposed individual. The SNAC2 area dosemeter, an improvement of SNAC50, makes it possible to restore neutron spectrum shapes from the integral data of a few activation detectors, and to calculate the useful dosimetric quantities with the appropriate conversion factors. The thermal and epithermal components of the spectral distribution are determined by means of 1) bare copper and 2) cadmium shielded gold and copper. The fast component of the spectrum is obtained with three threshold detectors, viz indium, nickel and magnesium allowing to assess the parameters of a representative mathematical function. The spectrum indexes make it possible to find out the variations of the spectral di stribution in order to obtain the dosimetric quantities ranges. An ebonite disk (sulfur activation) is included for the assessment of the dosimetric quantities to an exposed individual. The measurements of the sample activity are carried ou t by gamma spectrometry, except for ebonite which requires beta activity countin g. Data processing is carried out on a microcomputer. The BASIC programme is lis ted in appendix [fr

  20. Calibration of extremity dosemeters for gamma radiation fields

    International Nuclear Information System (INIS)

    Papadopulos, S.B.; Gregori, B.N.; Cruzate, J.A.

    1998-01-01

    In this work the kerma conversion factor are free in air, dose equivalent H(d,0 ) are presented, they were obtained theoretical and experimentally in finger and arm for gamma radiation fields. Extremity dosemeters put on surface finger and arm phantom have been irradiated. The finger phantom is a solid cylinder of PMMA polymethylmethacrylate 19 mm diameter and 300 mm height. The arm phantom is a 73 mm external diameter cylinder with PMMA walls 2.5 mm thick fill with water and 300 mm height. The radiation sources were cobalt 60 and cesium 137 from the Regional Center of Reference (CRR) of the National Commission of Atomic Energy (CNEA) and the Nuclear Regulatory Authority (ARN). Also in ISO wide X ray spectra W60, W110 and W200 have been irradiated. The results obtained show a good correlation with those published, they have a difference less than 7%. The factors will be applied to the evaluation of the equivalent doses coming from workers whose main irradiated zone is in the hands. (author)

  1. Numerical and experimental results of the operational neutron dosemeter 'Saphydose-N'

    International Nuclear Information System (INIS)

    Lahaye, T.; Chau, Q.; Menard, S.; Ndontcheung-Moyo, M.; Bolognese-Milsztajn, T.; Rannou, A.

    2004-01-01

    Since 1993, the Inst. for Radiological Protection and Nuclear Safety (IRSN) has lead, in association with Electricite de France (EDF), a R and D study of a neutron personal electronic dosemeter. This dosemeter, called 'Saphydose-N', is manufactured by the SAPHYMO company. This paper presents first the optimisation of some detector components using Monte Carlo calculations, and second the test of the manufactured Saphydose-N under radiation following the IEC 1323 standard's recommendations for active personal neutron dosemeters. The measurements with the manufactured dosemeter were performed on the one hand at PTB (Physikalisch-Technische Bundesanstalt) in mono-energetic neutron fields and, on the other hand at IRSN in neutron fields generated by a thermal facility (SIGMA), radionuclide ISO sources and a realistic spectrum (CANEL/T400). The manufactured dosemeter Saphydose-N was also tested during measurement campaigns of the European programme EVIDOS ('Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields') at different nuclear workplaces. The study showed that Saphydose-N complies with the recommendations of standard IEC 1323 and can be used at any workplace with no previous knowledge of the neutron field characteristics. (authors)

  2. New developments of Czech Personnel Neutron Dosemeter and its application

    International Nuclear Information System (INIS)

    Trousil, J.; Spurny, F.; Kralik, M.; Zelenka, Z.

    2001-01-01

    There are two systems for neutron personal dosimetry used at practice in the Czech Republic: - solid state nuclear track detectors in contact with fissionable materials (intermetallic enriched U + AI alloy, and 232 Th) in Cd shield badge, and - Albedo dosimeter based on 6 LiF and 7 LiF thermoluminescent detectors in a plastic badge covered from the front side by Cd to screen it from directly coming thermalized neutrons. The first system is used in National Personal Dosimetry Service; its performance is continuously checked and improved. In this contribution we would like to present some of results of this development, the contribution to the calibration of the second system included. (authors)

  3. Detection of irradiated foods by the thermoluminescence. Relationships between the temperature ranges of integrating TL glow curves and TL glow ratios

    International Nuclear Information System (INIS)

    Sekiguchi, Masayuki; Yamazaki, Masao; Goto, Michiko; Todoriki, Setsuko; Hagiwara, Shoji

    2007-01-01

    Our study demonstrated that the effects of the several temperature ranges for integrating TL glow intensity on the TL glow ratios by using spice-set purchased at a Turkish air port. The spice set had no labeling of irradiation feeds, but nine of 12 spices were judged as irradiated food in this study. Those temperature ranges were defined by evaluating the glow curves of irradiated TLD-100 chip (167-230degC), TLD-100 disc (177-238degC) and Dolomite element (145-258degC). Those are relatively stable and the difference of typical glow peak temperatures of TLD-100 disc in two institutes was less than 2%. On the other hand, those of TLD-100 tip was shift to higher temperature side at about 4degC because of declining of thermal conductance. The temperature ranges defined by TLD-100 were showed that discriminate more clearly between irradiated and nonirradiated spices compared with the full temperature range of TL measurement (70-400degC). With the exception of low glow intensity, background measurement for estimating net glow intensity was not necessary because TL glow ratio was hardly influenced whether the background measured or not. (author)

  4. Thermoluminescence method for detection of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Pinnioja, S

    1998-12-31

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  5. Thermoluminescence method for detection of irradiated food

    International Nuclear Information System (INIS)

    Pinnioja, S.

    1998-01-01

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  6. Thermoluminescence of Zn{sub 3}(PO{sub 4}){sub 2}:Mn{sup 2+} exposed to β radiation

    Energy Technology Data Exchange (ETDEWEB)

    Perez S, R.; Aceves, R.; Piters D, T.; Rodriguez M, R. [Universidad de Sonora, Departamento de Investigacion en Fisica, Hermosillo, Sonora (Mexico); Camarillo, I. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Camarillo, E., E-mail: rperez@cifus.uson.mx [UNAM, Instituto de Fisica, Cicuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2015-10-15

    The thermoluminescence (Tl) response and trapping analysis of Zn{sub 3}(PO{sub 4}){sub 2}:Mn{sup 2+} glass at room temperature after being exposed to a dose of β-irradiation is reported. The material shows a linear behavior for doses lower than 25 Gy. Measurements indicate that Tl glow curves are composed by several glow peaks. In order to verify this observation, partial heating technique has been applied. The result was the detection of at least four glow peaks located about 124, 199, 240, and 290 degrees C. The complete Tl glow curve shows a higher intensity at temperatures near 200 degrees C, which reduce possibilities of fading. A residual Tl analysis for different waiting times in the measurement of Tl indicate that low decay luminescent centers exist which correspond mainly to the first Tl glow peak. According with the result found, this type of material has potential to be used as β-irradiation dosemeter in different applications. (Author)

  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. Authenticity test in ceramics and archaeological figures by thermoluminescence

    International Nuclear Information System (INIS)

    Ramirez L, A.; Schaaf, P.; Filloy, L.

    1999-01-01

    At present exists quite a lot of false archaeological pieces which provokes doubts about the legitimacy of the pieces. In this work it is presented the Authenticity test by Thermoluminescence realized at the urn of the goddess 13 serpent of the zapotec culture of Oaxaca which is exposed in Mexico City. The original piece contains crystalline structures which present hardly the thermoluminescence phenomena by the presence of 238 U, 232 Th, and 40 K getting with this the form and intensity of the natural thermoluminescence curve of an archaeological piece which shows a Tl peak and allows to know so if it was made recently or not. (Author)

  9. The Value of Digital Personal Dosemeters in Angiography/Interventional Radiology: Preliminary Experience

    International Nuclear Information System (INIS)

    Casey, M.; Malone, D.E.

    2001-01-01

    New interventional procedures tend to involve longer screening times than were hitherto used in radiology. A careful audit of technique and shielding facilities needs to be performed to ensure that patient and operator doses are optimised. This paper explores the use of digital dosemeters to evaluate operator dose. Equipment related parameters, e.g. screening time, dose-area-product readings, were not found to be strongly correlated to operator dose. The real time display on the electronic dosemeter is a non-intrusive indicator of the efficacy of operator protection strategies. (author)

  10. Response dependence of an albedo-neutron dosemeter on the properties of shielding

    International Nuclear Information System (INIS)

    Doerschel, B.; Herforth, L.; Schuricht, V.

    1976-07-01

    The ratio of the response of an albedo-neutron dosemeter to the biological neutron dose has been calculated for pile and 14-MeV neutrons in dependence on the thickness of several shielding materials, such as iron, water, and concrete. The results obtained show great differences of this ratio for pile and 14-MeV neutrons. Therefore, errors in estimating the biological neutron dose due to changes in the primary neutron energy spectra beyond shields limit the application of simple albedo-neutron dosemeters

  11. The natural thermoluminescence of meteorites. VI - Carbon-14, thermoluminescence and the terrestrial ages of meteorites

    Science.gov (United States)

    Benoit, P. H.; Jull, A. J. T.; Mckeever, S. W. S.; Sears, D. W. G.

    1993-01-01

    A relationship is noted between the natural thermoluminescence (TL) levels and the C-14-derived terrestrial ages for meteorite finds from the U.S. Prairie States and Roosevelt County, NM; those in the Sahara are also in accord with calculated TL decay curves, for 'storage' temperatures equal to the approximate average annual temperatures at individual sites. This discussion is limited to the empirical correspondence between the two methodologies, and to theoretical decay curves for a single 'average' ordinary chondrite.

  12. 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...

  13. 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)

  14. 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)

  15. Thermoluminescence of natural and synthetic diopside

    Energy Technology Data Exchange (ETDEWEB)

    Cano, N.F. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900 Sao Paulo (Brazil)], E-mail: nilocano@dfn.if.usp.br; Yauri, J.M. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900 Sao Paulo (Brazil); University of Alas Peruanas, Environmental Engineering, Arequipa (Peru); Watanabe, S. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900 Sao Paulo (Brazil); Mittani, J.C.R. [Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072 (United States); Blak, A.R. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900 Sao Paulo (Brazil)

    2008-07-15

    Diopside, a natural silicate mineral of formula CaMgSi{sub 2}O{sub 6}, has been investigated concerning its thermoluminescence (TL) and electron paramagnetic resonance (EPR) properties. Glow curves and TL vs. {gamma}-dose were obtained irradiating natural samples to additional dose varying from 50 to 10,000 Gy. Except for a 410 deg. C peak found in the Al-doped artificial diopside, all the other peaks grow linearly with radiation dose, but saturate beyond {approx}1 kGy. To investigate high-temperature effect before irradiation, measurements of TL intensity in samples annealed at 500-900 deg. C and then irradiated to 1 kGy {gamma}-dose were carried out. Also the TL emission spectrum has been obtained. To compare with natural diopside, a synthetic pure polycrystal was produced and further those doped with iron, aluminum and manganese were also produced.

  16. Identification of irradiated food by thermoluminescent method

    International Nuclear Information System (INIS)

    Vo Van Thuan; Pham Quang Vinh; Tran Manh Hung; Dang Thanh Luong; Pham Quang Dien

    1990-01-01

    Thermoluminescent (TL) effect of irradiated dried food was observed by using the TL apparatus TOLEDO. Clear difference of TL intensity between irradiated sample and reference was found for chilies, black pepper, turmeric finger powder and gram green. For chilies powder and black pepper, TL effect was investigated in dependence on increasing absorbed dose from 0.5 to 20 kGy and fading effect was studied during storage time up to third month. When black pepper has linear dependence on dose up to 20 kGy, chilies effect catches a saturation at dose higher 5 kGy. TL effect was found very small after sample's washing, which shows an important role of inorganic impurity in TL effect. (author). 7 refs, 3 figs, 2 tabs

  17. Environmental radiation studies relevant to thermoluminescence dating

    International Nuclear Information System (INIS)

    Murray, A.S.; Bowman, S.G.E.; Aitken, M.J.

    1980-01-01

    To determine the age of a potsherd by the thermoluminescence (TL) technique, one must have an accurate knowledge of the cosmic and environmental gamma dose rate in quartz. This is obtained by leaving a sensitive TL dosimeter buried as near as possible to the position from which the sherd was removed. The ratios of the response of a quartz-like dosimeter to those of CaF 2 and LiF have been measured. This experiment used a 1-m cube of concrete containing 3000 ppM of uranium and its daughters. Smaller, less active matrixes of 40 K and thorium and its daughters have also been constructed. A means of making direct dose-rate determinations when the site context remains but burial of a dosimeter is impractical was developed using a NaI(Tl) system. The equipment was field tested on approx. 40 Peruvian archaeological sites, and results are compared with CaF 2 measurements

  18. 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.

  19. Mechanism of thermoluminescence in Vietnam natural quartz

    International Nuclear Information System (INIS)

    Tran Ngoc; Nguyen Manh Son; Phan Tien Dung; Trinh The Cuong; Nguyen Trong Thanh; Vu Xuan Quang

    2006-01-01

    Thermoluminescence properties of the Vietnam's natural quartz showed a number of peaks in the glow curve at 100 o C and 325 o C. the TL emission spectrum mainly consisted of three broad emission bands located at around 380 nm (3.26 eV), 470 nm (2.64 eV) and 610 nm (2.03 eV). These peaks were attributed to the [H 3 O 4 ] 0 hole centres, [AlO 4 ] 0 centres and E ' centres (oxygen vacancy), respectively. The main effect of blue light (450 nm) exposure was the appearance of the distinctive 110 o C TL peak and a reduction of the 325 o C TL peak. The observed relationship between TL intensity and illumination wavelength was consistent with those reported in the work of Botter-Jensen et al. (1994b) who suggested a linear relationship between logarithm of intensity and the photon energy. (author)

  20. 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)

  1. Thermoluminescence in alkali halides irradiated at 80K

    International Nuclear Information System (INIS)

    Jimenez de Castro, M.

    1978-01-01

    The thermoluminescence, the thermally stimulated currents and the thermal stability of the F centres induced in pure NaCl and KC1 crystals by X irradiation at 80K have been studied in detail, in the range between 80 and 300K. The thermoluminescent processes induced by illumination at 80K with F light in samples previously irradiated at room temperature has also been studied. It has been clearly observed the existence of thermoluminescent processes due to electrons and holes thermally released from traps, in which the F centres are not involved. The existence of hole-F centre recombination has not been observed. There are several thermoluminescent processes in both materials which are scribed to the recombination of F centres with mobile interstitial halogen atoms thermally released from traps, which are likely monovalent impurities in this temperature interval. The light emitting stage in these processes is originated by the formation of self trapped excitons. (Author) 66 refs

  2. 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

  3. Storage Telemetry of Radionuclide Tracers by Implantable Thermoluminescent Dosimeters

    DEFF Research Database (Denmark)

    Bojsen, J.; Møller, U.; Christensen, Poul

    1977-01-01

    A storage telemetrical method using thermoluminescent (TL) dosimeters for long-term measurements of incorporated radioactive substances in unrestrained rats has been developed. The system has been used in combination with radiotelemetrical registration of the circadian temperature rhythm. By sequ...

  4. Eurados trial performance test for personal dosemeters for external beta radiation

    DEFF Research Database (Denmark)

    Christensen, P.; Bordy, J.M.; Ambrosi, P.

    2001-01-01

    On the initiative of the European Dosimetry Group (EURADOS) action group 'Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation' a trial performance test for whole-body and extremity personal dosemeters broadly representative of those in use in the EU...

  5. A measurement of the response to fast neutrons of several materials dosemeters

    International Nuclear Information System (INIS)

    Jones, L.T.; Kitching, S.J.; Lewis, T.A.; Playle, T.S.

    1986-07-01

    The response to fast neutrons was measured for three types of materials testing dosemeters: fast neutron dosimetry silicon diodes; beryllia, alumina and calcium fluoride TLDs; graphite walled ionisation chambers. The calibrations were made using a 3MW positive ion accelerator. The arrangement of the target, beam monitor and devices is described, and the measured fast neutron sensitivities are presented. (UK)

  6. Tl response of LiF: Mg, Cu, P+Ptfe at X rays of 24, 42 and 100 KeV

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.; Tovar M, V.M.; Azorin N, J.; Furetta, C.; Quiroz C, M.C.

    2005-01-01

    In this work the obtained results of the irradiation of thermoluminescent dosemeters (Tl) of LiF: Mg,Cu,P + Ptfe with X rays for the effective radiation energy of 24, 42 and 100 keV, in an interval of Kerma in air in the sinus of the air between 0.05 and 1.0 Gy are presented. The rate of Kerma in air was determined with an ionization chamber PTW-1152, gauged by the Laboratoire Central des Industries Electriques (LCIE). As reference commercial TLD-100 dosemeters was used. The results showed that the studied Tl dosemeters presented a lineal response in the interval of mentioned Kerma. On the other hand the estimated Kerma with the Tl dosemeter in the calibration curves for X rays, were similar to the one measured with the previously gauged ionization chamber. The Tl of LiF: Mg, Cu, P + Ptfe, developed in the ININ, are highly reliable for X-ray dosimetry. (Author)

  7. Tl response of LiF: Mg, Cu, P+Ptfe at X rays of 24, 42 and 100 KeV; Respuesta TL de LiF: Mg, Cu, P+Ptfe a rayos X de 24, 42 y 100 KeV

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P.R.; Tovar M, V.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Azorin N, J. [UAM-I, 09340 Mexico D.F. (Mexico); Furetta, C. [Universita degli Studi di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185 Roma (Italy); Quiroz C, M.C. [Facultad de Medicina, UAEM, 50180 Toluca, Estado de Mexico (Mexico)

    2005-07-01

    In this work the obtained results of the irradiation of thermoluminescent dosemeters (Tl) of LiF: Mg,Cu,P + Ptfe with X rays for the effective radiation energy of 24, 42 and 100 keV, in an interval of Kerma in air in the sinus of the air between 0.05 and 1.0 Gy are presented. The rate of Kerma in air was determined with an ionization chamber PTW-1152, gauged by the Laboratoire Central des Industries Electriques (LCIE). As reference commercial TLD-100 dosemeters was used. The results showed that the studied Tl dosemeters presented a lineal response in the interval of mentioned Kerma. On the other hand the estimated Kerma with the Tl dosemeter in the calibration curves for X rays, were similar to the one measured with the previously gauged ionization chamber. The Tl of LiF: Mg, Cu, P + Ptfe, developed in the ININ, are highly reliable for X-ray dosimetry. (Author)

  8. Calibration of a special neutron dosemeter based on solid-state track detectors and fission radiators in various neutron fields

    International Nuclear Information System (INIS)

    Doerschel, B.; Krusche, M.; Schuricht, V.

    1980-01-01

    The calibration of a personnel neutron dosemeter in different neutron fields is described. The badge-like dosemeter contains 5 detectors: polycarbonate foil (10 μm, Makrofol KG), 232 Th, natural uranium, natural uranium with boron, and natural uranium with cadmium. Detector sensitivity and calibration factors have been calculated and measured in radiation fields of 252 Cf fission neutrons, WWR-S reactor neutrons with and without Cd and Fe shielding, 3-MeV (d,t) generator neutrons, and 238 PuBe neutrons. Measurement range and achievable accuracy are discussed from the point of view of applying the dosemeter in routine and emergency uses

  9. 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.

    1994-01-01

    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 are evaluated in this paper for selected characteristics relevant to environmental monitoring, along with two conventional phosphors widely used in environmental monitoring. 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 and routine processing protocols. Annealing and readout protocols for each phosphor were optimized for use in a large-scale environmental monitoring program

  10. Energy dependence of ulrathin LiF-dosemeters for high energy electrons and high energy X-radiation

    International Nuclear Information System (INIS)

    Kupfer, T.

    1977-02-01

    The energy dependence of ultrathin LiF-dosemeters for high energy electrons (5-40 MeV) and high energy X-radiation (6 MV, 42 MV) is experimentally determined. The experimental values are compared to values calculted earlier by other authors. The influence of the thickness of the dosemeters have been considered by comparison of experimental values for 0.03 mm thick dosemeters and theoretical values for 0.13 mm and 0.38 mm thick ones. Also different commersially available dosemeters have been compared by experiments. It is difficult to draw any other conclutions about the energy dependence than that the variation of the relative responce is within +- 3 percent (2S). However the results seems to be sulficient for clinical applications

  11. Performance of a PADC personal neutron dosemeter at simulated and real workplace fields of the nuclear industry.

    Science.gov (United States)

    Fiechtner, A; Boschung, M; Wernli, C

    2007-01-01

    In the framework of the EVIDOS (Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields) project, funded by the EC, measurements with PADC personal neutron dosemeters were carried out at several workplace fields of the nuclear industry and at simulated workplace fields. The measured personal neutron dose equivalents of the PADC personal neutron dosemeter are compared with values that were assessed within the EVIDOS project by other partners. The detection limits for different spectra types are given. In cases were the neutron dose was too low to be measured by the PADC personal neutron dosemeter, the response is estimated by convoluting the responses to monoenergetic neutrons with the dose energy distribution measured within EVIDOS. The advantages and limitations of the PADC personal neutron dosemeter are discussed.

  12. Performance of a PADC personal neutron dosemeter at simulated and real workplace fields of the nuclear industry

    International Nuclear Information System (INIS)

    Fiechtner, A.; Boschung, M.; Wernli, C.

    2007-01-01

    In the framework of the EVIDOS (Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields) project, funded by the EC, measurements with PADC personal neutron dosemeters were carried out at several workplace fields of the nuclear industry and at simulated workplace fields. The measured personal neutron dose equivalents of the PADC personal neutron dosemeter are compared with values that were assessed within the EVIDOS project by other partners. The detection limits for different spectra types are given. In cases were the neutron dose was too low to be measured by the PADC personal neutron dosemeter, the response is estimated by convoluting the responses to monoenergetic neutrons with the dose energy distribution measured within EVIDOS. The advantages and limitations of the PADC personal neutron dosemeter are discussed. (authors)

  13. Thermoluminescent and impedimetric studies on irradiated foodstuffs

    International Nuclear Information System (INIS)

    Mamoon, A.M.

    2000-01-01

    Several brands of different spices and milk powders were irradiated with relatively high doses of gamma radiation. Glow curves were produced upon heating these irradiated foodstuffs only. Study of the obtained spices glow curves revealed that the magnitude of these curves depends upon the dose received while the shape of the curves remains generally the same for the different doses and for the different spices. Previous studies had shown that the obtained thermoluminescence (TL) is due to dust particles carried by the spices. The TL studies show, furthermore, that different brands of the same spice are apparently contaminated with different amounts of dust or soil. The obtained TL from irradiated milk powders is apparently due to its mineral content. Different milk powders gave TL curves of different magnitudes for the same dose depending upon the milk brand. Impedimetric studies carried out irradiated potatoes show changes in impedance amplitude and phase angle. The results support earlier work on the use of TL to differentiate between irradiated and control foodstuffs, to assess the extent of spices contamination with soil-which perhaps reflects hygienic care-and that impedimetric measurements can distinguish irradiated from control potatoes

  14. Thermoluminescence of zircon: a kinetic model

    CERN Document Server

    Turkin, A A; Vainshtein, D I; Hartog, H W D

    2003-01-01

    The mineral zircon, ZrSiO sub 4 , belongs to a class of promising materials for geochronometry by means of thermoluminescence (TL) dating. The development of a reliable and reproducible method for TL dating with zircon requires detailed knowledge of the processes taking place during exposure to ionizing radiation, long-term storage, annealing at moderate temperatures and heating at a constant rate (TL measurements). To understand these processes one needs a kinetic model of TL. This paper is devoted to the construction of such a model. The goal is to study the qualitative behaviour of the system and to determine the parameters and processes controlling TL phenomena of zircon. The model considers the following processes: (i) Filling of electron and hole traps at the excitation stage as a function of the dose rate and the dose for both (low dose rate) natural and (high dose rate) laboratory irradiation. (ii) Time dependence of TL fading in samples irradiated under laboratory conditions. (iii) Short time anneali...

  15. Photoinduced emission and thermoluminescence in topaz

    International Nuclear Information System (INIS)

    Dantas, Samuel Cesar; Giroldo Valerio, Mario Ernesto; Couto dos Santos, Marcos Antonio; Souza, Divanizia do Nascimento

    2006-01-01

    Topaz has been demonstrated to be useful for dosimetric application. This mineral exhibits a satisfactory thermoluminescent (TL) response to radiation. In previous studies we analyzed the natural topaz samples from Minas Gerais, Brazil, by TL, infrared and X-ray diffraction techniques, with the aim of obtaining an explanatory model for the process of light emission of this mineral. Thermal treatments and irradiations do not produce significant changes in the TL emission. TL spectra exhibit a broad band with a maximum TL intensity at 420 nm in all the samples. In order to better understand the physical processes involved in the light emission of the topaz, we analyzed the photoinduced fluorescence of natural (as received) and thermally treated samples in powder form. The photoinduced emission of topaz was found to be similar to that of other silicates. In the UV-visible range there are intense emission bands between 350 and 550 nm, with a maximum intensity at 435 nm. The intensities are different for each sample

  16. Thermoluminescence properties of irradiated chickpea and corn

    Energy Technology Data Exchange (ETDEWEB)

    Necmeddin Yazici, A. [University of Gaziantep, Department of Engineering, Physics, 27310 Gaziantep (Turkey)], E-mail: yazici@gantep.edu.tr; Bedir, Metin; Bozkurt, Halil [University of Gaziantep, Department of Engineering, Physics, 27310 Gaziantep (Turkey); Bozkurt, Hueseyin [University of Gaziantep, Department of Food Engineering, 27310 Gaziantep (Turkey)

    2008-02-15

    A study was carried out to establish a detection method for irradiated chickpea and corn by thermoluminescence (TL) method. The leguminous were packed in polyethylene bags and then the packets were irradiated at room temperature at different doses by {sup 60}Co gamma source at 1, 4, 8 and 10 kGy. Minerals extracted from the leguminous were deposited onto a clean aluminum disc and TL intensities of the minerals were measured by TL. It was observed that the extracted samples from both leguminous exhibit good TL Intensity and the TL intensity of glow curves of them increased proportionally to irradiation doses. The TL glow curve of both irradiated leguminous presents a single broad peak below 400 degC. The TL trapping parameters glow peaks were estimated by the additive dose (AD), T{sub m}(E{sub a})-T{sub stop} and computerized glow curve deconvolution (CGCD) methods. The fading characteristics of glow curves were also recorded up to 6 months.

  17. Evaluation of environmental monitoring thermoluminescent dosimeter locations

    International Nuclear Information System (INIS)

    Kinnison, R.

    1992-12-01

    Geostatistics, particularly kriging, has been used to assess the adequacy of the existing NTS thermoluminescent dosimeter network for determination of environmental exposure levels. (Kriging is a linear estimation method that results in contour plots of both the pattern of the estimated gamma radiation over the area of measurements and also of the standard deviations of the estimated exposure levels.) Even though the network was not designed as an environmental monitoring network, ft adequately serves this function in the region of Pahute and Rainier Mesas.. The Yucca Flat network is adequate only if a reasonable definition of environmental exposure levels is required; R is not adequate for environmental monitoring in Yucca Flat if a coefficient of variation of 10 percent or less is chosen as the criterion for network design. A revision of the Yucca Flat network design should be based on a square grid pattern with nodes 5000 feet (about one mile) apart, if a 10 percent coefficient of variation criterion is adopted. There were insufficient data for southern and western sections of the NTS to perform the geostatistical analysis. A very significant finding was that a single network design cannot be used for the entire NTS, because different areas have different variograms. Before any design can be finalized, the NTS management must specify the exposure unit area and coefficient of variation that are to be used as design criteria

  18. Thermoluminescence sensitivity of daily use materials

    International Nuclear Information System (INIS)

    Correcher, V.; Sanchez M, L.; Delgado, A.; Garcia G, J.; Rivera M, T.

    2007-01-01

    Full text: Both radiation accidents and radiological terrorism could be evaluated with the help of environmental materials that can act as potential- dosimeters. The luminescence of ceramic materials (bricks, tiles or insulators) has been successfully investigated to be applied in the field of retrospective dosimetry, however, studies on the luminescence emission of some other domestic or-industrial materials have been scarcely achieved. Several.of these daily-use material$ such as: chemicals used in laundry (mixture of sodium polyphosphate and sodium sulphate), vitreous materials (windows, glasses, etc., made of aluminosilicates), cellular phone chips (made of doped silicon), common salt (sodium chloride), dental crowns (mainly made of silicates), construction plates (marble and granite) or gems (corundum or sapphire, Al 2 O 3 ; charoite, K 5 Ca 8 (Si 6 O 15 )(Si 2 O 7 )(Si 4 O 8 ) (OH) 3H 2 O, pectolite NaCa 2 Si 3 O 8 (OH), etc.), exhibit a reasonable sensitivity to radiation and high reproducibility of the thermoluminescence (TL) emission. The features of these materials allow us to think that could be used for dose reconstruction in areas affected by a radiological accident where do not necessarily conventional dosimetric systems can be ready. This work focuses on the study of (i) the chemical and structural characterisation of some of the aforementioned materials by means of X-ray diffraction, electron probe microanalysis (EPMA) and X-ray fluorescence (XRF) and (ii) the radiation sensitivity based on their TL properties. (Author)

  19. Dose evaluation in diagnostic for computerized tomography; Evaluacion de dosis en diagnostico por tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Flores, W.; Borges, J.C.; Mota, H. [Universidad Federal de Rio de Janeiro, PEN/COPPE/UFRJ. Caixa Postal 68509. 21945-970 Rio de Janeiro (Brazil)

    1998-12-31

    The patients which are subjected to computerized tomography tests are exposed to relatively high doses given as result doses on organs that are not matter to test. It was realized a dose levels raising in patients subjected to tests by T C, utilizing to measure this magnitude, TLD-100 thermoluminescent dosemeters which were put directly on the patient, in eye regions, thyroid, breast and navel; founding doses fluctuating between 29.10-49.39 mGy in organs examined and dose values between 0.21-29.10 mGy for organs that no matter to test. The applications of ionizing radiations in medicine do not have dose limits, but paying attention to the radiological protection optimization principle, it is recommended the use of clothes to anti-rays protection for zones not examined, getting with this to reduce the level doses as low as possible, without this to diminish the test quality. (Author)

  20. Dose evaluation in diagnostic for computerized tomography

    International Nuclear Information System (INIS)

    Flores, W.; Borges, J.C.; Mota, H.

    1998-01-01

    The patients which are subjected to computerized tomography tests are exposed to relatively high doses given as result doses on organs that are not matter to test. It was realized a dose levels raising in patients subjected to tests by T C, utilizing to measure this magnitude, TLD-100 thermoluminescent dosemeters which were put directly on the patient, in eye regions, thyroid, breast and navel; founding doses fluctuating between 29.10-49.39 mGy in organs examined and dose values between 0.21-29.10 mGy for organs that no matter to test. The applications of ionizing radiations in medicine do not have dose limits, but paying attention to the radiological protection optimization principle, it is recommended the use of clothes to anti-rays protection for zones not examined, getting with this to reduce the level doses as low as possible, without this to diminish the test quality. (Author)

  1. Method of evaluation of diagnostics reference levels in computerized tomography

    International Nuclear Information System (INIS)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  2. Method of evaluation of diagnostics reference levels in computerized tomography; Metodo de avaliacao de niveis de referencia de radiodiagnostico em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  3. Estimation of equivalent dose on the ends of hemodynamic physicians during neurological procedures; Avaliacao da dose equivalente nas extremidades de medicos hemodinamicistas durante procedimentos neurologicos

    Energy Technology Data Exchange (ETDEWEB)

    Squair, Peterson L.; Souza, Luiz C. de; Oliveira, Paulo Marcio C. de [Universidade FUMEC, Belo Horizonte, MG (Brazil). Radiologia e Protecao Radiologica; Nogueira, Maria do S. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2005-07-01

    The estimation of doses in the hands of physicists during hemodynamic procedures is important to verify the application of radiation protection related to the optimization and limit of dose, principles required by the Portaria 453/98 of Ministry of Health/ANVISA, Brazil. It was checked the levels of exposure of the hands of doctors during the use of the equipment in hemodynamic neurological procedures through dosimetric rings with thermoluminescent dosemeters detectors of LiF: Mg, Ti (TLD-100), calibrated in personal Dose equivalent HP (0.07). The average equivalent dose in the end obtained was 41.12. {mu}Sv per scan with an expanded uncertainty of 20% for k = 2. This value is relative to the hemodynamic Neurology procedure using radiological protection procedures accessible to minimize the dose.

  4. Systematic errors in the readings of track etch neutron dosemeters caused by the energy dependence of response

    CERN Document Server

    Tanner, R J; Bartlett, D T; Horwood, N

    1999-01-01

    A study has been performed to assess the extent to which variations in the energy dependence of response of neutron personal dosemeters can cause systematic errors in readings obtained in workplace fields. This involved a detailed determination of the response functions of personal dosemeters used in the UK. These response functions were folded with workplace spectra to ascertain the under- or over-response in workplace fields.

  5. Use of a robotic manipulator in the simulation of the automation of a calibration process of dosemeters

    International Nuclear Information System (INIS)

    Benitez R, J.S.; Najera H, M.C.

    2002-01-01

    The development of a system based in a manipulative robot which simulates the operative sequence in a calibration process of dosemeters is presented. In this process it is performed the monitoring of the dosemeter positions and the calibrator by mean of an arm of articulated robot which develops the movement sequences and the taking a decision based on the information coming from the external sensors. (Author)

  6. Application of a thermoluminescence method for detection of irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Gastelum, S.; Osuna, I.; Melendrez, R.; Cruz-Zaragoza, E.; Chernov, V.; Calderon, T.; Barboza-Flores, M

    2002-07-01

    Food irradiation is extremely effective at reducing food-borne illness as well as losses caused by infestation and contamination. Despite the well-established regulations that permit irradiation to control pathogens in spices, there are no widespread methods to detect previously irradiated food. Therefore, it has become necessary to develop new detection and dose determination methods for food subjected previously to irradiation. The present work deals with the application of the thermoluminescence (TL) phenomenon to detect irradiated spices. The process is based upon the thermoluminescence properties exhibited by the polymineral content of the irradiated specimen. After separating the organic material, it is possible to extract some polymineral substances that are suitable for thermoluminescence analysis due to interaction of the spice to ionising radiation. The method was successfully applied to examine irradiated and non-irradiated paprika of Mexican origin. The spice was irradiated with gamma rays at doses of 5, 10 and 15 kGy. The separated thermoluminescent polymineral was found to be composed mainly of quartz and feldspar. The thermoluminescence glow curve of the irradiated specimen shows a side band peaked 228, 268 and 336 deg. C, resembling pretty much the combined TL of quartz and feldspars. The method allows for the determination of the retrospective dose exposure. (author)

  7. 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)

  8. Development of a neutron dosemeter for personnel dosimetry with direct response of dose equivalent in neutron fields of different energy spectra. 1

    International Nuclear Information System (INIS)

    Doerschel, B.

    1978-12-01

    An energy-independent neutron dosemeter is described. The dosemeter is based on a dielectric track detector (mica foil of 6 μm thickness) between uranium and a thorium-232 radiator pulverized and pressed with polyvinyl alcohol enclosed within a cadmium shell. The track density is direct proportional to the dose equivalent between 5 x 10 -4 and 10 Sv. When evaluated every two months, the dosemeter has for 3 mSv an error of +- 50% decreasing at higher dose equivalents

  9. Comparison between the distribution of the calculated dose and the media with thermoluminescent dosemeters 7 LiF in bladder tumor

    International Nuclear Information System (INIS)

    Araujo, A.M.C. de.

    1974-01-01

    For the central plane of an assumed malignant tumor of the bladder, Cobalt - 60 treatment plans were calculated from published isodose curves. The calculation was done for the three field technique, unbalanced and balanced, and for 120 degree rotational therapy with wedge filter. A Rando-Alderson phantom and calibrated encapsulated 7 LiF dosimeters with a standard deviation better than 3% of each were used to verify the treatment plans. Furthermore the dose distribution to an assumed extension of the tumor and to the rectum were measured. (author)

  10. Thermoluminescence of thin films deposited by laser ablation

    International Nuclear Information System (INIS)

    Escobar A, L.; Camps, E.; Arrieta, A.; Romero, S.; Gonzalez, P.R.; Olea M, O.; Diaz E, R.

    2003-01-01

    Materials in thin film form have received great attention in the last few years mainly because of their singular properties, which may differ significantly from their bulk attributes making them attractive for a wide variety of applications. In particular, thermoluminescence (Tl) properties of thin films have been studied recently owing to their potential applications in detection for both ionizing and non ionizing radiation. The aim of the present work is to report the synthesis and characterization of C Nx, aluminum oxide and titanium oxide thin films. Thermoluminescence response of the obtained thin films was studied after subject thin films to UV radiation (254 nm) as well as to gamma radiation (Co-60). Thermoluminescence glow curves exhibited a peak centered at 150 C for CN x whereas for titanium oxide the glow curve shows a maximum peaking at 171 C. Characterization of the physical properties of the deposited materials is presented. (Author)

  11. Effect of particle size on the thermoluminescent response of hydroxyapatite

    International Nuclear Information System (INIS)

    Barrera V, A.; Zarate M, J.; Contreras, M. E.; Rivera M, T.

    2016-10-01

    We present the study of the structural characterization and the thermoluminescent response of the hydroxyapatite as a function of the calcination temperature and the effect of the particle size. For precipitation synthesis, calcium nitrate (Ca(NO 3 ) 2 and dibasic ammonium phosphate ((NH 4 ) 2 HPO 4 ) were used as precursors and ammonium hydroxide (NH 4 OH) as a ph controlling agent. The characterization of the samples was carried out by the techniques of X-ray diffraction, scanning electron microscopy and infrared spectroscopy. The powders obtained are composed of hydroxyapatite, with a different degree of dehydroxylation. The thermoluminescent characterization indicates that at higher calcination temperature there is a higher thermoluminescent response, the calcined powders at 1300 degrees Celsius show a very well defined brightness curve with a higher intensity, with its maximum intensity located at a temperature of 210 degrees Celsius, which indicates that this material can be used as a dosimeter. (Author)

  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. Temperature distribution in thermoluminescence experiments. Pt. 1

    International Nuclear Information System (INIS)

    Betts, D.S.; Couturier, L.; Khayrat, A.H.; Luff, B.J.; Townsend, P.D.

    1993-01-01

    In a typical thermoluminescence experiment, a sample rests on a metallic strip which is heated in a controlled fashion so that the strip temperature rises linearly with time. Thermal contact is improved by the use of an inert exchange gas, usually argon. With this procedure, samples of interest emit light spectra of low intensity as electrons escape from traps. The technique is applied, for example, to dating of artefacts or geological materials, to radioactive dosimetry, and to the characterization of optical materials. In this paper we present data which show that it is unsafe to make the common assumption that, during ramping, the light-emitting parts of the sample have the same temperature as the heating strip. We have performed experiments designed to demonstrate sizeable temperature differences. This is important where data from different laboratories are compared and we conclude that practitioners should routinely take note of the following points. Firstly, ramping rates should be as low as possible consistent with the optical sensitivity available (there is a trade-off between the two, but temperature differences are likely to be important where ramping rates exceed 5 K s -1 ). Secondly, it is advisable to use helium as exchange gas rather than the more usual argon, because it is a much better conductor of heat. Thirdly, users should do a few basic thermal experiments with their apparatus so that, with the aid of formulae given in the paper which follows this one, they can make corrections where these are important. This is the first of a linked pair of papers on this subject; it is primarily about experimental results, while the second (following) paper offers some theory which can be applied. (author)

  14. Influence of different types of phantoms on the calibration of dosemeters for eye lens dosimetry

    International Nuclear Information System (INIS)

    Yoshitomi, H.; Kowatari, M.

    2016-01-01

    Both a cylinder and a slab phantom have been recommended to be used as calibration phantoms for eye lens dosimetry in the International Atomic Energy Agency TECDOC. This study describes investigations on the influence of the type of phantom on the calibration of dosemeters. In order to fulfil the purpose, backscatter radiation from practically used water-filled phantoms was evaluated by calculations and experiments. For photons, the calculations showed that the cylinder phantom had 10 % lower backscattered effect at maximum than a slab phantom, and simulated well the backscattered effect of the human head or neck to within ±10 %. The irradiation results of non-filtered optically stimulated luminescence and radio-photoluminescence glass dosemeters indicated that the differences of the calibration factors between the two types of phantoms were up to 20 and 10 %, respectively, reflecting the response to backscattered photons. For electrons, no difference was found between the two types of phantoms. (authors)

  15. Contemporary calibration of photon personal dosemeters on slab phantoms. Numerical and experimental evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Gualdrini, G.; Monteventi, E.; Morelli, B. [ENEA, Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente

    1998-07-01

    The report discusses the experimental results obtained by the Secondary Standard Dosimetry Laboratory, belonging to the ENEA (National Agency for New Technology, Energy and the Environment) Institute for Radiation Protection at Bologna (Italy), and aimed at adopting routine procedures for the calibration of personnel dosemeters according to the ICRU recommendations. The reference ISO and ICRU recommended slab phantoms for calibrating dosemeters in terms of Hp(10,a) and Hp(0.07, a) have been therefore acquired. [Italian] Il rapporto presenta i risultati sperimentali di calibrazione di dosimetri personali in accordo con le raccomandazioni ICRU prodotti dal laboratorio secondario di dosimetria dell'Istituto di Radioprotezione dell'ENEA di Bologna. Sono stati acquisiti i fantocci piani di calibrazione raccomandati da ISO ed ICRU per calibrare i dosimetri nei termini di Hp(10,a) ed Hp(0.07, a).

  16. Automatic exploitation system for photographic dosemeters; Systeme d`exploitation automatique des dosimetres photographiques

    Energy Technology Data Exchange (ETDEWEB)

    Magri, Y.; Devillard, D.; Godefroit, J.L.; Barillet, C.

    1997-01-01

    The Laboratory of Dosimetry Exploitation (LED) has realized an equipment allowing to exploit automatically photographic film dosemeters. This system uses an identification of the films by code-bars and gives the doses measurement with a completely automatic reader. The principle consists in putting in ribbon the emulsions to be exploited and to develop them in a circulation machine. The measurement of the blackening film is realized on a reading plate having fourteen points of reading, in which are circulating the emulsions in ribbon. The exploitation is made with the usual dose calculation method, with special computers codes. A comparison on 2000 dosemeters has shown that the results are the same in manual and automatical methods. This system has been operating since July 1995 by the LED. (N.C.).

  17. Operational trials of single- and multi-element CR-39 dosemeters for the DIDO and PLUTO reactors at the Harwell Laboratory

    International Nuclear Information System (INIS)

    Gallacher, G.G.; Perks, C.A.

    1993-01-01

    Single- and multi-element CR-39 dosemeters, developed at the Harwell Laboratory, and a commercially available multi-element CR-39 dosemeter (obtained from Track Analysis Systems Ltd), were evaluated for their potential as neutron dosemeters for personnel working at Harwell Laboratory's research reactors. Owing to the angular dependence of the CR-39 (processed using electrochemical etching), the single-element dosemeter was found to be impractical. Consequently, a multi-element dosemeter was developed, which consisted of a cube of side 36 mm with CR-39 elements (also processed using electrochemical etching) attached to each of the sides. Although this dosemeter was technically suitable for this type of dosimetry, it was considered to be unacceptably bulky in personnel trials. The commercially available CR-39 dosemeter tested was much smaller (the CR-39 was only chemically etched) and this was considered to be acceptable as a personnel dosemeter. In addition, trials with personnel working at active handling glove boxes indicated that single-element dosemeters might be adequate, but further work would be needed to verify this. (author)

  18. Eye lens dose monitoring in the UK nuclear industry using active personal dosemeters.

    Science.gov (United States)

    McWhan, Andrew Forrest; Dobrzynska, Wioletta

    2017-11-20

    The reduction of the dose limit for eye lens from 150 to 20 mSv year-1 must be implemented by EU member states by February 2018. Consequently, there is a requirement for all employers engaged with work with ionising radiation to have appropriate monitoring arrangements in place by this date to demonstrate that they can meet this new limit for all workers. Eye lens dose is conventionally monitored by specific dosemeters worn near the eye. However, it is usually impractical for these dosemeters to be worn at all times in the workplace which can lead to problems accounting for any periods of work when an eye lens dosemeter has not been worn. The Berkeley Approved Dosimetry Service provides a monitoring service for 22 nuclear sites in the UK using active personal dosemeters (APDs) for measuring Hp(10) and Hp(0.07). TLDs for extremity and eye are also issued as appropriate for the working conditions. An analysis of the data from 2007 to 2016 concludes that the values for Hp(0.07) as monitored indirectly by APDs worn on the trunk are comparable to the values assessed by specific Hp(3) eye TLDs. This paper sets out evidence that compliance with the 20 mSv dose limit for the eye lens can be demonstrated using routine issue APDs although specific eye TLDs may still be required to meet international guidance for non-uniform workplace fields. This evidence supports the recent statement from IRPA that "for the nuclear industry and other non-medical sectors the use of a whole body dosimeter is considered likely to be sufficient for the majority of workers". © 2017 IOP Publishing Ltd.

  19. Chronology of Chichen Izta, evidences by thermoluminescence; Cronologia de Chichen Izta, evidencias por termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, A.; Schaaf, P. [Laboratorio de Termoluminiscencia, Instituto de Geofisica, UNAM, 04510 Mexico D.F. (Mexico); Gonzalez, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Chung, H. [Facultad de Filosofia y Letras, UNAM, 04510 Mexico D.F. (Mexico)

    2002-07-01

    The establishment of the chronology of Chichen Itza is argued by its stylistic evocations, architectural and iconographical as well as its history related in the sources, as the Chilam Balam, where is named the arrival of foreign tribes as the Xiu and the Itzaes and its settlement in Chichen Itza as well as the return to its origin place. The material evidence of such transition is reflected in the ceramic change of the Pizarra Puuc to the Pizarra Chichen, however, in 13 stratigraphic wells realized in different points of Chichen Itza, it was not found evidence of the layer of the Pizarra Puuc period. In this work the obtained ages of dating by thermoluminescence (TL) are presented, of four samples of ceramics found in the different wells. When our results are compared with the estimated ages for the different groups of ceramics, it was observed that none of they corresponded to the Pizarra Puuc period. These results strenghten the observations realized during excavations, causing the suggestion of new inferences related to the Chichen Itza boom and its relationship with the Maya Classic Period. The used technique for the TL dating was that of fine grain. The interval of artificial dose, of beta radiation of Strontium 90 was between 2 and 30 Gy. The TL signal was obtained heating the samples at 10 C/s until reaching 500 C in the TL Daybreak reader equipment. In order to know the annual dose rate of concentration of potassium ({sup 40} K) by means of the microanalysis technique in the scanning electron microscope was determined, while the uranium content (2{sup 38} U) and thorium ({sup 232} Th) were determined by means of the neutron activation analysis technique using the TRIGA Mark III nuclear reactor. The contribution of the gamma radiation of the soil as well as the contribution of the cosmic radiation was measured with TL dosemeters of CaSO{sub 4} :Dy + Ptfe once the paleodose was known and the annual dose rate of each sample of its age was estimated. (Author)

  20. Thermoluminescence studies on plant seeds of different radiosensitivity

    International Nuclear Information System (INIS)

    Yamaguchi, Hikoyuki; Eguchi, Hoshio; Koizumi, Yoshinobu.

    1975-01-01

    The thermoluminescence was found when the pulverized powders from the whole seeds of six plant species or the hypocotyls from the seeds of five soybean varieties were irradiated at a liquid nitrogen temperature with gamma-rays. The spectra of luminescence emitted, the light peak temperature, the decaying after irradiation and the dose relationship of luminescence were determined. A high yield of the rapidly-decaying luminescence occurred in the more radiosensitive variety when irradiated with relatively lower doses. The very drastic decrease of the thermoluminescence was observed in the samples irradiated at room temperature prior to the exposure at 77 0 K. (auth.)

  1. Evaluation of two personal dosemeters in polyenergetic mono- and multi-directional neutron fields

    International Nuclear Information System (INIS)

    Nunes, J. C.; Surette, R. A.

    2005-01-01

    The neutron dose-equivalent response of two commercially available electronic personal neutron dosemeters was studied in several laboratory-produced broad-spectrum neutron fields. Fluence-weighted mean energies ranged from 200 keV to 4 MeV; personal dose-equivalent rates ranged from 75 to 10 mSv h -1 ; and angles of incidence were multidirectional, 0 deg., 30 deg. and 60 deg.. Three of these fields have been shown previously to resemble ones found in CANDU (Canadian Deuterium Uranium is a registered trademark of the Atomic Energy of Canada Limited) power plant workplaces. Both dosemeters were found to perform reasonably well across the range of energy spectra and angles of incidence. One type of dosemeter displayed values of the personal dose equivalent that were, at worst, within a factor of ∼2 of the reference values and, at best, within a few per cent of the reference values. The other type displayed values of the personal dose equivalent that were consistently within unity and 20% of the reference values. Although the radiological performance of one was found to be more accurate, this device was also found to be the less rugged of the two. Some of the data acquired in this work were compared with results previously published by others. There was consistency between these sets of data. (authors)

  2. A portable versatile x-and γ-ray dosemeter with digital display for medical use

    International Nuclear Information System (INIS)

    Sankaran, A.; Gangadharan, P.

    1980-01-01

    A multipurpose dosemeter based on analogue-to-digital (A-D) conversion has been developed using solid state devices, micropower integrated circuits and displays. The A-D converter combines the features of a MOSFET electrometer, a voltage-to-frequency converter, the automatic Townsend balance, LED(LCD) display for exposure, analogue output and has a voltage-measuring accuracy of +-O.1% FS+-1 digit. The dosemeter which is designed to measure a wide range of X- and γ-ray exposure rates (1 mRh -1 to 1000 R min -1 ) and exposures (1 mR to 1000 R) with a variety of air-equivalent ionisation chambers, is compact, rugged and battery or AC mains powered. It is designed to provide trouble-free performance, easy operation and maintenance and to be independent of climatic conditions. Combining the features of a survey meter, dosemeter and a radioisotope calibrator, it can be fabricated using the facilities locally available in hospitals or universities. (author)

  3. The thermoluminescence as tool in the reconstruction of volcanic events; La termoluminiscencia como herramienta en la reconstruccion de eventos volcanicos

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez L, A.; Schaaf, P.; Martin del Pozzo, A.L.; Gonzalez M, P. [Instituto de Geofisica, UNAM, C.P. 04500, Mexico D.F. (Mexico)

    2000-07-01

    Within the Mexican land a great number of volcanoes are situated which a considerable part of them are still active. The relevance of dating pomex deposits, ash or lava of these poly genetic volcanoes is to determine the periodicity and magnitude of the volcanic events happened. In this work is presented the preliminary result of the dating by thermoluminescence in a pomex of a pyroclastic flux coming from a volcano in the state of Puebla with the purpose of providing elements to the knowledge which describe the eruptive history of the explosive volcanism at center of Mexico. For the sample dating the volcanic glasses of pomex were separated and it was applied the fine grain technique with a grain size between 4-11 {mu} m. In order to calculate the rate of annual dose it was carried out the following: in the determination of {sup 238} U and {sup 232} Th radioisotope concentration was used the neutron activation technique in a nuclear reactor, in the determination of the K 40 radioisotope was used a scanning electron microscope, the rate of environmental and cosmic dose was measured arranging Tl dosemeters of CaSO{sub 4}: Dy in the sampling place. In order to calculate the paleodoses it was carried out the following: the equivalent dose (Q) was determined starting form the additive method and the supra linearity factor (I) starting from regenerative method and in both methods the irradiated process was realized with a {sup 90} Sr beta source. With the above determinations it was calculated a paleodoses of 231 Gy and a rate of annual dose of 6.074 x 10{sup -3} Gy/year, estimating an age of: Age{sub pomez} = 231 Gy / 6.074 Gy x 10{sup -3} Gy /year = 38030 {+-} 4000 years. (Author)

  4. Thermoluminescence characteristics of the Li{sub 2}CO{sub 3}–K{sub 2}CO{sub 3}–H{sub 3}BO{sub 3} glass system co-doped with CuO and MgO

    Energy Technology Data Exchange (ETDEWEB)

    Alajerami, Yasser Saleh Mustafa, E-mail: yasser_ajr@hotmail.com [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Department of Medical Radiography, Al-Azhar University, Gaza Strip, Palestine (Country Unknown); Hashim, Suhairul; Ramli, Ahmad Termizi; Saleh, Muneer Aziz [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Kadni, Taiman [Secondary Standard Dosimetery Lab, Malaysian Nuclear Agency, 4300 Kajang, Selangor (Malaysia)

    2013-11-15

    In this work, the thermoluminescence (TL) properties of lithium potassium borate (LKB) doped with CuO and co-doped with MgO were determined for the first time. The induced TL glow curves of CuO doped samples were found to be produced at 220 °C with a single prominent peak. An enhancement of about three times is shown with every increment of 0.1 mol% MgO as a co-dopant impurity. This enhancement may attribute to the ability of magnesium to create extra traps and consequently the energy transfer to monovalent Cu ions. LKB:Cu,Mg has low Z material (Z{sub eff}=8.55), good reproducibility and a linear dose response in a long span of irradiation doses. The current phosphor showed sensitivity 15 times less than that of LiF:Mg,Ti (TLD-100). The trap parameters, including order of kinetics (b), activation energy (E) and frequency factor (s) associated with LKB:Cu,Mg were also determined. The photoluminescence (PL) spectra (emission and excitation) for the prepared sample were studied and compared with the TL spectra. It is clear that LKB:Cu,Mg shows higher TL and PL intensity as compared to LKB:Cu. Thus, Mg plays an important role in the enhancement of the TL and PL intensity of LKB:Cu phosphor. -- Highlights: • Enhancement of about three times has been shown with the increment of MgO. • LKB:Cu,Mg showed a close tissue equivalent value (Z{sub eff} equal to 8.55). • LKB:Cu,Mg showed good dose response linearity up to 10{sup 3} Gy. • The addition of MgO improved the TL and PL intensity by ∼2.7 factors. • The fading results showed 8% reduction after 10 days and 18% after 90 days.

  5. The thermoluminescence of carp otoliths: A fingerprint in ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... This paper reports a pilot study on the thermoluminescence (TL) of carbonate minerals of carp otoliths from the heavily polluted Baiyangdian Lake (BYD) in Hebei Province and non-polluted Miyun Water. Reservoir (MY) in Beijing Municipality of China. Analyses on trace elements of otoliths and water show.

  6. The thermoluminescence of carp otoliths: A fingerprint in ...

    African Journals Online (AJOL)

    This paper reports a pilot study on the thermoluminescence (TL) of carbonate minerals of carp otoliths from the heavily polluted Baiyangdian Lake (BYD) in Hebei Province and non-polluted Miyun Water Reservoir (MY) in Beijing Municipality of China. Analyses on trace elements of otoliths and water show that the heavy ...

  7. 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.

  8. Spatially-resolved thermoluminescence from snail opercula using an EMCCD

    DEFF Research Database (Denmark)

    Duller, G.A.T.; Kook, Myung Ho; Stirling, R.J.

    2015-01-01

    In recent years opercula of the snail species Bithynia tentaculata have been shown to emit thermoluminescence (TL) signals that can be used to determine equivalent dose, and may be capable of dating events throughout the entire Quaternary period. Concentric growth lines are a notable feature of a...

  9. The thermoluminescent curve as parameter to compare archaeological ceramics

    International Nuclear Information System (INIS)

    Dominguez R, I.R.; Ramirez C, G.A.; Gonzalez M, P.R.; Mendoza A, D.; Martinez C, G.

    2006-01-01

    Most mineral materials, including the constituents of pottery, have the property of thermoluminescence (TL), where part of the energy from radioactive decay in the mineral is stored and later released as light upon strong heating. The intensity of emitted light as a function of temperature is the thermoluminescence glow curve. However, it is well-know the thermoluminescence glow curve form depends of several factors associates with the incident radiation and type of materials. Between the factors associated with the materials, it can be mentioned the quantity and type of crystalline phases, and quantity and type of impurities that they could be present in the material. That is to say, materials with different physicochemical characteristics will produce different thermoluminescence glow curve, although, they have been irradiated under the same conditions. In accordance with the above mentioned, it is possible to identified differences between pre hispanic ceramic belonging to a same site and other sites. In this work a discussion about advantages and disadvantages is presented. Some specific examples in ceramic artifacts belonging to the Matlatzinca and Teotihuacan cultures are included. (Author)

  10. Assessment of the suitability of zircons for thermoluminescence dating

    NARCIS (Netherlands)

    van Es, HJ; den Hartog, HW; de Meijer, RJ; Venema, LB; Donoghue, JF; Rozendaal, A

    2000-01-01

    A suit of zircon (ZrSiO4) samples has been selected for experiments by thermoluminescence (TL) and by Laser Ablation ICP-MS to study the role of rare earth elements (REE). It is shown that the trace element composition results for the heavy REE (HREE) are consistent, and that zircons are HREE

  11. Thermoluminescence in gamma irradiated iPP-VGVGCNF

    Energy Technology Data Exchange (ETDEWEB)

    Cherestes, Margareta [S. C. Dozimed SRL, Bucharest (Romania); Constantinescu, Livia Maria [University of Bucharest, Faculty of Physics, Magurele, Bucharest (Romania); Chipara, Dorina Magdalena, E-mail: dchipara@utpa.edu [The University of Texas Pan-American, Department of Physics and Geology, Edinburg, TX 78539 (United States); Cherestes, Codrut [S. C. Dozimed SRL, Bucharest (Romania); Chipara, Mircea [The University of Texas Pan-American, Department of Physics and Geology, Edinburg, TX 78539 (United States)

    2013-06-15

    Nanocomposites have been obtained by dispersing various amounts of vapor grown carbon nanofibers within isotactic polypropylene via melt mixing. The as obtained nanocomposites were gamma irradiated at various integral doses by using a {sup 60}Co source. The irradiation was performed in air, at room temperature, and at a dose rate of about 1 kGy/h up to an integral dose of 28 kGy. Thermoluminescence investigations revealed the role of carbon nanotubes in the radiation-induced modification of polymer-based nanocomposites. Almost all samples (pristine polymer and polymer-based nanocomposites irradiated and not irradiated) showed two overlapping thermoluminescence signals. It is concluded that the dispersion of carbon nanotubes decreases the amount of trapped electrons improving eventually the radiation stability of the polymeric matrix. The low temperature thermoluminescence peak was tentatively associated to melting phenomena. The origin of the high temperature thermoluminescence peak is more complex. Nevertheless, the experimental data suggests that this peak is sensitive to the polymer-filler interface.

  12. Deconvolution of the thermoluminescent emission curve. Second order kinetics

    International Nuclear Information System (INIS)

    Moreno y M, A.; Moreno B, A.

    1999-01-01

    In this work it is described the Randall and Wilkins second order kinetics in Microsoft Excel language, which allows its expression as the sum of Gaussian and the correction factors corresponding. These factors are obtained of the differences between the real thermoluminescent curve and the Gaussian proposed. The results obtained justify the Gaussian expression added to the correction factor. (Author)

  13. Thermoluminescence characteristics of Sm doped NaYF4 crystals

    Indian Academy of Sciences (India)

    2006-06-28

    Jun 28, 2006 ... investigation of spectroscopic properties of rare earth ions incorporated into different inorganic host matrices from the view point of searching for new materials with appli- cations in lasers, optical devices, solid state dosimeters, etc. Thermoluminescence (TL) studies help in understanding the emission of ...

  14. Development of a highly sensitive lithium fluoride thermoluminescence dosimeter

    International Nuclear Information System (INIS)

    Moraes da Silva, Teresinha de; Campos, Leticia Lucente

    1995-01-01

    In recent times, LiF: Mg, Cu, P thermoluminescent phosphor has been increasingly in use for radiation monitoring due its high sensitivity and ease of preparation. The Dosimetric Materials Production Laboratory of IPEN, (Nuclear Energy Institute) has developed a simple method to obtain high sensitivity LiF. The preparation method is described. (author). 4 refs., 1 fig., 1 tab

  15. The thermoluminescence of carp otoliths: A fingerprint in ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... that the heavy metal elements of BYD were much higher than those of MY, particularly on chromium ... These heavy metal elements could infiltrate ..... the thermoluminescence survey in prospecting for in-situ leachable sand stone type uranium deposit. Uranium Geol. 18: 118-121. Mao MZ, Liu ZH, Dong HR ...

  16. 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)

  17. Trace element geochemistry and thermoluminescence (TL) of quartz ...

    African Journals Online (AJOL)

    *

    Otolith is a typical biomineral carrier growing on insides of fish skull with prominent zoning structure formed by alternating layers of protein and calcium carbonate growing around the nucleus. Even though thermoluminescence (TL) analysis on biomineral has been widely used to measure the radiation exposure in the ...

  18. 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

  19. Characteristics and performance of the Sunna high dose dosemeter using green photoluminescence and UV absorption readout methods

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.D.; Murphy, M.K.; Tinker, M.R.; Kovacs, A.; McLaughlin, W

    2002-07-01

    Growth in the use of ionising radiation for medical sterilisation and the potential for wide-scale international food irradiation have created the need for robust, mass-producible, inexpensive, and highly accurate radiation dosemeters. The Sunna dosemeter, lithium fluoride injection-moulded in a polyethylene matrix, can be read out using either green photoluminescence or ultraviolet (UV) absorption. The Sunna dosemeter can be mass-produced inexpensively with high precision. Both the photoluminescent and the UV absorption reader are simple and inexpensive. Both methods of analysis display negligible humidity effects, minimal dose rate dependence, acceptable post-irradiation effects, and permit measurements with a precision of nearly 1% 1s. The UV method shows negligible irradiation temperature effects from -30 deg. C to +60 deg. C. The photoluminescence method shows negligible irradiation temperature effects above room temperature for sterilisation dose levels and above. The dosimetry characteristics of these two readout methods are presented along with performance data in commercial sterilisation facilities. (author)

  20. Influence of the stem effect on radioluminescence signals from optical fibre Al2O3:C dosemeters

    DEFF Research Database (Denmark)

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

    2006-01-01

    This paper analyses the influence of the Cerenkov radiation and other noise sources, the so-called stem effect, on radioluminescence (RL) signals generated in optical fibre Al2O3:C dosemeters used in medical dosimetry. The optical fibre dosemeter consists of a sensitive Al2O3:C crystal coupled...... to an optical fibre cable that carries the RL and optically stimulated luminescence (OSL) signals generated in the Al2O3:C crystal. During irradiation of the dosemeter, the real-time dose rate can be determined from the RL signal and after irradiation the total dose absorbed is determined from the OSL signal...... stimulated using a focused green solid-state laser. In particular, the components of the stem effect generated in the fibres were analysed to determine their impact on the RL signal....

  1. Optical fibre dosemeter systems for clinical applications based on radioluminescence and optically stimulated luminescence from Al2O3:C

    DEFF Research Database (Denmark)

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

    2006-01-01

    for making ultra-small dosemeter probes that can easily be placed inside patients in radiation treatment. These probes have shown excellent properties in both head and neck intensity-modulated radiation therapy treatment and in mammography. The dose-response of the OSL signal for the new optical fibre......Optical fibre dosemeter systems based on radioluminescence and optically stimulated luminescence (OSL) from carbon-doped aluminium oxide (Al2O3:C) crystals were developed for in vivo real-time dose rate and absorbed dose measurements in radiotherapy and mammography. A technique was also developed...... dosemeter system showed a repeatability within 0.15% at a dose level of 60 mGy when integrated over 100 s. The temperature dependence in the range 0-45 degrees C showed a reproducibility within 1.3% when the OSL signal was integrated over 100 s....

  2. Influence of the PMMA and the ISO slab phantom for calibrating personal dosemeters

    International Nuclear Information System (INIS)

    Ginjaume, M.; Ortega, X.; Barbosa, A.

    2000-01-01

    Wide agreement has been achieved among the main Bodies and Organisations involved in standardisation of radiation protection, related to the operational quantities for personal dosimetry. Since their definition in 1985, several reports have been published to clarify and define the experimental set up to be used for the calibration of dosemeters in terms of the above-mentioned quantities. Among these lines, ICRU 47 has listed five different phantoms that are used for calibration and whose results were accurate, within accepted uncertainties. However, to achieve uniformity in calibration procedures, the 30 cm x 30 cm x 15 cm PMMA slab phantom was recommended. The secondary calibration Laboratory from the Institut de Techniques Energetiques at the Technical University of Catalonia (UPC) agreed with the Spanish Nacional Laboratory to adopt the recommended PMMA phantom but to improve the accuracy of the calibration procedure, by introducing a correction factor for backscatter differences in a PMMA and an ICRU slab phantom. Such corrections were of the order of 8% for the low-energy X-ray qualities. Recently, ISO in ISO 4037-3, has proposed the ISO water slab phantom which consists of a 30 cm x 30 cm x 15 cm water phantom with PMMA walls (front wall 2.5 mm thick). This new phantom could be substituted by the above mentioned PMMA phantom for radiation qualities with mean energy equal or above that of 137 Cs. The aim of this work is to compare the influence of both phantoms when calibrating personal dosemeters with photons. A set of four TL personal dosemeters that are used in the UPC personal dosimetry Service and an electronic personal dosemeter (SIEMENS EPD-2) were calibrated in terms of H p (10) and H p (0.07) using the two proposed phantoms. Calibration factors for ISO X-ray narrow spectra, 137 Cs and 60 Co were experimentally obtained for each phantom and compared. In the TL measurements, differences were found to be within TL statistical uncertainty, provided that a

  3. A filter technique for optimising the photon energy response of a silicon pin diode dosemeter

    International Nuclear Information System (INIS)

    Olsher, R.H.; Eisen, Y.

    1996-01-01

    Unless they are energy compensated, silicon PIN diodes used in electronic pocket dosemeters, have significant over-response below 200 keV. Siemens is using three diodes in parallel with individual filters to produce excellent energy and angular response. An algorithm based on the photon spectrum of a single diode could be used to flatten the energy response. The commercial practice is to use a single diode with a simple filter to flatten the energy response, despite the mediocre low energy photon. The filter technique with an opening has been used for energy compensating GM detectors and proportional counters and a new variation of it has been investigated which compensates the energy response of a silicon PIN diode and maintains an extended low energy response. It uses a composite filter of two or more materials with several openings whose individual area is in the range of 15% to 25% of the diode's active area. One opening is centred over the diode's active area and others are located at the periphery of the active area to preserve a good polar response to ±45 o . Monte Carlo radiation transport methods were used to simulate the coupled electron-photon transport through a Hamamatsu S2506-01 diode and to determine the energy response of the diode for a variety of filters. In current mode, the resultant dosemeter energy response relative to air dose was within -15% and +30% for 0 o incidence over the energy range from 15 keV to 1 MeV. In pulse mode, the resultant dosemeter energy response was within -25% and +50% for 0 o incidence over the energy range from 30 keV to 10 MeV. For ±45 o incidence, the energy response was within -25% and +40% from 40 keV to 10 MeV. Theoretical viability of the filter technique has been shown in this work (Author)

  4. Validation of response simulation methodology of Albedo dosemeter; Validacao da metodologia de simulacao de resposta de dosimetro de Albedo

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, B.M.; Silva, A.X. da, E-mail: bfreitas@nuclear.ufrj.br [Coordenacao do Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Mauricio, C.L.P. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    The Instituto de Radioprotecao e Dosimetria developed and runs a neutron TLD albedo individual monitoring service. To optimize the dose calculation algorithm and to infer new calibration factors, the response of this dosemeter was simulated. In order to validate this employed methodology, it was applied in the simulation of the problem of the QUADOS (Quality Assurance of Computational Tools for Dosimetry) intercomparison, aimed to evaluate dosimetric problems, one being to calculate the response of a generic albedo dosemeter. The obtained results were compared with those of other modeling and the reference one, with good agreements. (author)

  5. Cr-39 fast neutron dosemeter based on A (n, α) converter

    International Nuclear Information System (INIS)

    Widayati, S.; Budiantari, T.

    1998-01-01

    The aim of this experiment is to obtained the response of Cr-39 as fast neutron dosemeter based on an (n, α) converter. Cr-39 was irradiated to AmBe fast neutron flux from 0.10 mSv to 2.5 mSv. Cr-39 processed by chemical etching with NaOH 20 % at temperature of 60 oC in six hours. The results of experiment showed that the response of Cr-39 based on an (n, α) converter is 6 times bigger than the response of Cr-39 without (n, α) converter. (author)

  6. 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)

  7. 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

  8. Statistical methods to evaluate thermoluminescence ionizing radiation dosimetry data

    Energy Technology Data Exchange (ETDEWEB)

    Segre, Nadia; Matoso, Erika; Fagundes, Rosane Correa, E-mail: nadia.segre@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CEA/CTMSP), Ipero, SP (Brazil). Centro Experimental Aramar

    2011-07-01

    Ionizing radiation levels, evaluated through the exposure of CaF{sub 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)

  9. Thermoluminescence authentication of T`ang and Han Dynasty pottery

    Energy Technology Data Exchange (ETDEWEB)

    Price, D.M. [Wollongong Univ., NSW (Australia). School of Geosciences

    1997-12-31

    More than 80 pieces of T`ang Dynasty and 40 Han Dynasty style ceramic wares have been analysed to determine the amount of thermoluminescence (TL) accumulated since the initial firing of the object and the level of the radiation flux which has created the TL. This paper presents a summary of the thermoluminescence analysis results. Approximately 60% of Han ceramics and 45% of the T`ang pottery authenticated have been shown to belong to periods other than that stylistically suggested. Items which have been found not to be of the anticipated antiquity generally fall into distinct age groups. Of the T`ang wares the most commonly copied item is found to be the horse and for the Han pieces, human figures and ewers/pots/vases represent the most frequently reproduced wares.

  10. Thermoluminescence authentication of T'ang and Han Dynasty pottery

    International Nuclear Information System (INIS)

    Price, D.M.

    1997-01-01

    More than 80 pieces of T'ang Dynasty and 40 Han Dynasty style ceramic wares have been analysed to determine the amount of thermoluminescence (TL) accumulated since the initial firing of the object and the level of the radiation flux which has created the TL. This paper presents a summary of the thermoluminescence analysis results. Approximately 60% of Han ceramics and 45% of the T'ang pottery authenticated have been shown to belong to periods other than that stylistically suggested. Items which have been found not to be of the anticipated antiquity generally fall into distinct age groups. Of the T'ang wares the most commonly copied item is found to be the horse and for the Han pieces, human figures and ewers/pots/vases represent the most frequently reproduced wares

  11. Thermoluminescent characteristics of inorganic dust from black pepper spice

    International Nuclear Information System (INIS)

    Furetta, C.; Cruz Z, E.; Favalli, A.

    2007-01-01

    Full text: The irradiation of spices is normally used for its sterilization, allowing this procedure to extend the storage time ir different needs, i.e. transportation over large distances from the production places to distribution points for commercialization. The irradiated food allows studying the behaviour and the characteristics of its inorganic content, i.e. minerals. The aim of this work is to study the main thermoluminescent (TL) characteristics of the inorganic dust extracted from Black pepper spice. TL responses as a function of the delivered gamma dose, fading at room temperature, effect of W irradiation are reported. The thermoluminescent kinetic parameters of the glow curves have been accurately analysed using the Computerized Glow Curve Deconvolution (CGCD) method and results are discussed. (Author)

  12. Preliminary research on thermoluminescence application in complicated geological situation

    International Nuclear Information System (INIS)

    Gong Gelian; Liu Chunsheng

    2003-01-01

    Thermoluminescent phenomenon resulting from two kinds of complicated geological situation, Ordos Basin and Huainan deposits in Anhui Province, is studied by the means of thermoluminescence counting method. It is shown that: (1) there are no apparent abnormalities of natural TL detected from the rock samples selected in the first 1000 meter depth of the Earth, and these natural TL are accumulated through natural radiation effects; (2) the natural TL shows statistically obvious reducing trends for the rock samples selected under the 2000 meter depth, and even no detectable TL is found for those rocks selected at 4000 meter depth. (3) the natural TL peaks corresponding to high temperature generally shift to the direction of higher temperature for the quartz-related rock samples, and several thermal events which occurred during the geological times might be responsible for this case

  13. Comparative study of thermoluminescent responses of diverse CVD diamonds

    Czech Academy of Sciences Publication Activity Database

    Krása, Josef; Marczewska, B.; Vorlíček, Vladimír; Olko, P.; Juha, Libor

    2007-01-01

    Roč. 16, - (2007), s. 1510-1516 ISSN 0925-9635 R&D Projects: GA MŠk 1P04LA235; GA MŠk LC510 Institutional research plan: CEZ:AV0Z10100520 Keywords : CVD diamond * thermoluminescence * read-out cycle * X-ray dosimetry Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.788, year: 2007

  14. Storage Telemetry of Radionuclide Tracers by Implantable Thermoluminescent Dosimeters

    DEFF Research Database (Denmark)

    Bojsen, J.; Møller, U.; Christensen, Poul

    1977-01-01

    A storage telemetrical method using thermoluminescent (TL) dosimeters for long-term measurements of incorporated radioactive substances in unrestrained rats has been developed. The system has been used in combination with radiotelemetrical registration of the circadian temperature rhythm. By sequ......, in subcutaneous tissues and tumor tissue. This TL method permits the repetition of an experiment on the same rat several times, and thereby avoids errors due to biological variations between animals....

  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. A study of the high-temperature signal characteristics in the thermoluminescence of porcelain

    International Nuclear Information System (INIS)

    Yin Gongming

    2001-01-01

    The thermoluminescence pre-dose technique for dating ancient porcelain was developed in many laboratories. This technique was the only method which could directly determine the age of old porcelain. But the thermoluminescence high-temperature signal (over 200 degree C) had not been studied. The authors conduced a preliminary study of the characteristic of thermoluminescence high-temperature signal, such as the TL natural glow curve, and the glow curves after beta or alpha irradiation. Most of the 32 ancient porcelains had thermoluminescence high temperature signal, and only one peak in their TL glow curve was found

  17. Variation in thermoluminescence of irradiated brands of foodstuffs: a test for hygienic quality

    International Nuclear Information System (INIS)

    Mamoon, A.; Zaheer, A.; Abu-Abdullah, S.

    1996-01-01

    Thermoluminescence of irradiated foodstuffs such as herbs and spices, is mostly due to attached dust or soil particles. Different brands of the same foodstuff sometimes give thermoluminescent signals of different intensities, apparently due to different degrees of dust contamination. It is of obvious importance to choose brands of foodstuffs that appear to have less dust contamination, i.e. of better hygienic quality. Several food items were investigated with respect to their thermoluminescent (TL) emission in order to assess TL usefulness as an indicator of hygienic quality for foods prone to contamination by dust. In this regard some foodstuff were artificially contaminated with a soil sample and their thermoluminescent emission was obtained. (author)

  18. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments.

    Science.gov (United States)

    Lee, K W; Sheu, R J

    2015-04-01

    High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with (252)Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing (252)Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6_8 extended-range sphere versus the 6″ standard sphere). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Calibration of the IRD two-component TLD albedo neutron dosemeter in some moderated neutron fields

    International Nuclear Information System (INIS)

    Freitas, Bruno M.; Silva, Ademir X. da

    2015-01-01

    In some stray neutron fields, like those found in practices involving the handling of radionuclide sources, the neutron calibration factor for albedo neutron dosemeter can vary widely compared to the factor for bare sources. This is the case for well logging, which is the area with the largest number of workers exposed to neutrons in Brazil. The companies employ routinely 241 Am-Be neutron sources. The albedo response variation is mainly due to the presence of scattered and moderated neutrons. This paper studies the response variation of the two-component TLD albedo neutron dosemeter used in the neutron individual monitoring service of Instituto de Radioprotecao e Dosimetria, in different radionuclide neutron source beams. The neutron spectra were evaluated applying a Bonner sphere spectrometer with a 6 LiI(Eu) detector in the Brazilian National Metrology Neutron Laboratory. Standard neutron sources of 241 Am-Be and 252 Cf were employed, besides 238 Pu-Be. Measurements were also made with scattered and moderated neutron beams, including 252 Cf(D 2 O) reference spectrum, 241 Am-Be moderated with paraffin and silicone and a thermal neutron flux facility. New neutron calibration factors, as a function of the incident to albedo neutron ratio, were proposed for use in the albedo algorithm for occupational fields where the primary neutron beam is one of those studied sources. (author)

  20. Re-Establishment of Standard Radiation Qualities for Calibration of Dosemeter in Diagnostic Radiology - RQR Series

    International Nuclear Information System (INIS)

    Asmaliza Hashim; Norhayati Abdullah; Mohd Firdaus Abd Rahman

    2016-01-01

    After repairing the high voltage (HV) generator for Philips MG165 X-Ray Machine, the reestablishment of the standard radiation qualities has been done at Medical Physics Calibration Laboratory to meet the IEC and IAEA standard. Standard radiation qualities are the important criteria for calibration of dosemeter in diagnostic radiology. Standard radiation qualities are defined as the added filtration needed to produce and the half value layer (HVL) of the beam for specifies x-ray tube kilo voltage (kV). For calibration of dosemeter in diagnostic radiology, standard radiation qualities RQR represent the beam incident on the patient in general radiography, fluoroscopy and dental application. The HVL were measured using PTW ion chamber of volume 1 cm 3 with PTW electrometer and aluminium filter with 99.9 % purity was used as additional filter for RQR and filter for HVL. The first establishment of standard radiation qualities was made in 2009 for the radiation qualities of RQR. The results of additional filter and 1st HVL from 2009 to 2016 will be discussed further in paper. The ratios of the measured HVL to the standard IEC HVL value for the RQR series also described in this paper. The details of the measurement and the results are described in this paper. (author)

  1. Three-dimensional absorbed dose determinations by N.M.R. analysis of phantom-dosemeters

    International Nuclear Information System (INIS)

    Gambarini, G.; Birattari, C.; Fumagalli, M.L.; Vai, A.; Monti, D.; Salvadori, P.; Facchielli, L.; Sichirollo, A.E.

    1996-01-01

    Magnetic resonance imaging of a tissue-equivalent phantom is a promising technique for three-dimensional determination of absorbed dose from ionizing radiation. A reliable method of determining the spatial distribution of absorbed dose is indispensable for the planning of treatment in the presently developed radiotherapy techniques aimed at obtaining high energy selectively delivered to cancerous tissues, with low dose delivered to the surrounding healthy tissue. Aqueous gels infused with the Fricke dosemeter (i.e. with a ferrous sulphate solution), as proposed in 1984 by Gore et al., have shown interesting characteristics and, in spite of some drawbacks that cause a few limitations to their utilisation, they have shown the feasibility of three-dimensional dose determinations by nuclear magnetic resonance (NMR) imaging. Fricke-infused agarose gels with various compositions have been analysed, considering the requirements of the new radiotherapy techniques, in particular Boron Neutron Capture Therapy (B.N.C.T.) and proton therapy. Special attention was paid to obtain good tissue equivalence for every radiation type of interest. In particular, the tissue equivalence for thermal neutrons, which is a not simple problem, has also been satisfactorily attained. The responses of gel-dosemeters having the various chosen compositions have been analysed, by mean of NMR instrumentation. Spectrophotometric measurements have also been performed, to verify the consistence of the results. (author)

  2. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments

    International Nuclear Information System (INIS)

    Lee, K.W.; Sheu, R.J.

    2015-01-01

    High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with 252 Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing 252 Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6-8 extended-range sphere versus the 6'' standard sphere). (authors)

  3. Viability of the Fricke dosemeter doped with methylene blue; Viabilidade do dosimetro Fricke dopado com azul de metileno

    Energy Technology Data Exchange (ETDEWEB)

    Souza, V.L.B.; Santos, C.D.A.; Rodrigues, K.R.G.; Cunha, M.S.; Figueiredo, M.D.C.; Melo, R.T. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2009-07-01

    This work aims to find the possible utilization of the Fricke dosemeter doped with methylene blue (FMB) for the dosimetry of photodynamic therapy. The FMB was irradiated wit X rays and light emitted diodes demonstrating positive answers to the stimulus, being probably to be used for dosimetric objectives

  4. Thermoluminescence, a method for determining the date at which a ceramic object was fired

    International Nuclear Information System (INIS)

    Sayre, E.V.

    The theory on which thermoluminescence dating of archeological ceramic objects is based and the measurement methods used are outlined. Separation of fine grain particles and quartz particles permits the determination of the thermoluminescence of each and often a more accurate age determination. The application of the method to the dating of a bronze horse from the Metropolitan Museum is described

  5. Thermoluminescence curves simulation using genetic algorithm with factorial design

    Science.gov (United States)

    Popko, E. A.; Weinstein, I. A.

    2016-05-01

    The evolutionary approach is an effective optimization tool for numeric analysis of thermoluminescence (TL) processes to assess the microparameters of kinetic models and to determine its effects on the shape of TL peaks. In this paper, the procedure for tuning of genetic algorithm (GA) is presented. This approach is based on multifactorial experiment and allows choosing intrinsic mechanisms of evolutionary operators which provide the most efficient algorithm performance. The proposed method is tested by considering the “one trap-one recombination center” (OTOR) model as an example and advantages for approximation of experimental TL curves are shown.

  6. Exoemission and thermoluminescence from human enamel and shark enameloid

    International Nuclear Information System (INIS)

    Davies, J.E.

    1983-01-01

    Simultaneous measurements of exoelectron emission and thermoluminescence from powdered biological apatites, which have not been chemically or thermally pretreated, are reported. Recycling, that is, consecutive irradiation and non-isothermal scanning, is shown to change both the form of the glow curves and emissivity of samples. Two biological apatites of the hydroxyapatite type (human enamel) and fluorapatite type (shark enameloid) are compared. Although their initial glow curves are different, recycling renders the glow curves similar suggesting that the defects involved are a product of the host lattice. The relevance of exoemission as a ''fingerprinting'' technique for biologically reactive material is discussed. (author)

  7. Thermoluminescent determination of prehistoric heat treatment of chert artifacts

    International Nuclear Information System (INIS)

    Melcher, C.L.; Zimmerman, D.W.

    1977-01-01

    In recent years archeologists have become interested in the extent to which prehistoric peoples heat-treated chert prior to shaping it into tools. Thermoluminescent determination of the radiation dose accumulated by an artifact since it was formed or last heated provides a simple, reliable test for such heat treatment. This test can be applied to single artifacts without the need for raw source material for comparison. Results on 25 artifacts from four sites indicate that, for many chert sources, color and luster are not useful indicators of heat treatment by prehistoric peoples

  8. 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)

  9. Thermoluminescence of the Z centre in Mg-doped KCl

    International Nuclear Information System (INIS)

    Kamavisdar, V.S.; Deshmukh, B.T.

    1980-01-01

    Optical absorption and thermoluminescence measurements on KCl:Mg 2+ are reported. Bleaching in F band introduces a new glow peak at 406 K in the glow curves. A similar peak is observed in microcrystalline powders. When this peak is thermally cleaned, the broadening of the absorption observed in prolonged F bleached crystals is removed. On the basis of these observations, the glow peak at 406 K is tentatively attributed to Z 1 centres. The glow peak at 394 K observed in microcrystalline powders is attributed to a combined effect of deformation and Z 1 centres. (author)

  10. 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)

  11. Thermoluminescence measurements of neutron streaming through JET Torus Hall ducts

    OpenAIRE

    Obryk, Barbara; Batistoni, Paola; Conroy, Sean; Syme, Brian D.; Popovichev, Sergey; Stamatelatos, Ion E.; Vasilopoulou, Theodora; Bilski, Paweł; Contributors, JET EFDA

    2014-01-01

    Thermoluminescence detectors (TLD) were used for dose measurements at JET. Several hundreds of LiF detectors of various types, standard LiF:Mg,Ti and highly sensitive LiF:Mg,Cu,P were produced. LiF detectors consisting of natural lithium are sensitive to slow neutrons, their response to neutrons being enhanced by 6Li-enriched lithium or suppressed by using lithium consisting entirely of 7Li. Pairs of 6LiF/7LiF detectors allow distinguishing between neutron/non-neutron components of a radiatio...

  12. 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)

  13. 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)

  14. On the second kinetic order thermoluminescent glow curves

    International Nuclear Information System (INIS)

    Dang Thanh Luong; Nguyen Hao Quang; Hoang Minh Giang

    1995-01-01

    The kinetic parameters of thermoluminescent material such as CaF 2 -N and CaSO 4 -Dy with the different grain sizes are investigated in detail using the least square method of fitting. It was found that the activation energy E (or trap depth) and peak temperature T m ax are changed with the elapsed time between the irradiation and read-out for the low temperature glow curve peaks. The similar TL glow curve shapes are obtained for the different CaSO 4 -Dy grain size. (author). 7 refs., 5 figs., 2 tabs

  15. Automation of radiation dosimetry using PTW dosemeter and LabVIEWTM

    International Nuclear Information System (INIS)

    Weiss, C.; Al-Frouh, K.; Anjak, O.

    2011-01-01

    Automation of UNIDOS 'Dosemeter' using personal computer (PC) is discussed in this paper. In order to save time and eliminate human operation errors during the radiation dosimetry, suitable software, using LabVIEW TM graphical programming language, was written to automate and facilitate the processes of measurements, analysis and data storage. The software calculates the calibration factor of the ionization chamber in terms of air kerma or absorbed dose to water according to IAEA dosimetry protocols. It also has the ability to print a calibration certificate. The obtained results using this software are found to be more reliable and flexible than those obtained by manual methods previously employed. Using LabVIEW TM as a development tool is extremely convenient to make things easier when software modifications and improvements are needed.

  16. Personal Dosemeter of Thermal Neutron Using A Cr-39 Detector with Filter Natural LiF

    International Nuclear Information System (INIS)

    Sofyan, Hasnel; Thamrin, M.Thoyib

    1996-01-01

    The research of personal dosemeter for thermal neutron using Cr-39 detector with different thicknesses of natural LiF filter was carried out. The irradiation of Cr-39 detector with neutron source from reactor research TRIGA mark II of Rikkyo University Tokyo, Japan. Nuclear track was counted by automatic method with ASPECT ver.4.22 Series A4T124 software and manual method for correction. The result of research, the maximum of nuclear tracks was obtained at 8 mm of LiF filter was 10 mm with 11,630x10E-5 track/neutron for air radiation. And on phantom radiation, the thickness of filter was 10 mm with 11,630x10E-5 track/neutron. Its values were 3.6 and 7.5 bigger than the response of Cr-39 non filter in air and on phantom radiation, respectively

  17. Measurement analysis using the Fricke dosemeter; Analise de medicoes com o dosimetro Fricke

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa, G.A.C. [Instituto Nacional de Metrologia (INMETRO), Rio de Janeiro, RJ (Brazil)], e-mail: gcpedrosa@inmetro.gov.br; Dantas, C.C. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear], e-mail: ccd@ufpe.br; Campos, C.A. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)], e-mail: auster@elogica.com.br

    2003-07-01

    The Fricke dosemeter has been used for absolute determination of the radiation dose between 40 and 350 Gy for X-rays, Gamma rays and fast electrons energies. The great inconvenient of that dosimetric system is the impossibility of using for measurements of exposure or low dose rates. A Fricke dosimetry system was implanted at the Nuclear Sciences Regional Center (CRCN), in Recife, Pernambuco state, Brazil, for the determination of radiation doses for spectrometry and mass dosimetry with plasma source. The statistical analysis of the obtained results have shown that using the spectrometric method that system cna be used for maintenance of factors of CRCN standard calibrations and the dose assessment thru mail system of radiotherapy centers of the country.

  18. Determination of isodose curves in Radiotherapy using an Alanine/ESR dosemeter; Determinacion de curvas de isodosis en Radioterapia usando un dosimetro de Alanina/ESR

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Baffa, O.; Graeff, C.F.O. [Departamento de Fisica e Matematica. Universidade de Sao Paulo FFCLRP. 14040-901 Ribeirao Preto-SP (Brazil)

    1998-12-31

    It was studied the possible use of an Alanine/ESR dosemeter in the isodose curves mapping in normal treatments of Radiotherapy. It was manufactured a lot of 150 dosemeters with base in a mixture of D-L Alanine dust (80 %) and paraffin (20 %). Each dosemeter has 4.7 mm diameter and 12 mm length. A group of 100 dosemeters of the lot were arranged inside 50 holes of the slice 25 of the phantom Rando Man. The phantom irradiation was realized in two opposed projections (AP and PA) in Co-60 equipment. A group of 15 dosemeters was take of the same lot for obtaining the calibration curve in a 1-20 Gy range. After irradiation the signal of each dosemeter was measured in an ESR spectrometer operating in the X-band ({approx} 9.5 GHz) and the wideness of Alanine ESR spectra central line was correlated with the radiation dose. The wideness dose calibration curve resulted linear with a correlation coefficient 0.9996. The isodose curves obtained show a profile enough similar at comparing with the theoretical curves. (Author)

  19. Study of a selection of 10 historical types of dosemeter: variation of the response to Hp(10) with photon energy and geometry of exposure.

    Science.gov (United States)

    Thierry-Chef, I; Pernicka, F; Marshall, M; Cardis, E; Andreo, P

    2002-01-01

    An international collaborative study of cancer risk among workers in the nuclear industry is tinder way to estimate direetly the cancer risk following protracted low-dose exposure to ionising radiation. An essential aspect of this study is the characterisation and quantification of errors in available dose estimates. One major source of errors is dosemeter response in workplace exposure conditions. Little information is available on energy and geometry response for most of the 124 different dosemeters used historically in participating facilities. Experiments were therefore set up to assess this. using 10 dosemeter types representative of those used over time. Results show that the largest errors were associated with the response of early dosemeters to low-energy photon radiation. Good response was found with modern dosemeters. even at low energy. These results are being used to estimate errors in the response for each dosemeter type, used in the participating facilities, so that these can be taken into account in the estimates of cancer risk.

  20. EURADOS intercomparisons in external radiation dosimetry: similarities and differences among exercises for whole-body photon, whole-body neutron, extremity, eye-lens and passive area dosemeters

    International Nuclear Information System (INIS)

    Romero, Ana M.; Grimbergen, Tom; McWhan, Andrew; Stadtmann, Hannes; Fantuzzi, Elena; Clairand, Isabelle; Neumaier, Stefan; Dombrowski, Harald; Figel, Markus

    2016-01-01

    The European Radiation Dosimetry Group (EURADOS) has been organising dosimetry intercomparisons for many years in response to an identified requirement from individual monitoring services (IMS) for independent performance tests for dosimetry systems. The participation in intercomparisons gives IMS the opportunity to show compliance with their own quality management system, compare results with other participants and develop plans for improving their dosimetry systems. In response to growing demand, EURADOS has increased the number of intercomparisons for external radiation dosimetry. Most of these fit into the programme of self-financing intercomparisons for dosemeters routinely used by IMS. This programme is being coordinated by EURADOS working group 2 (WG2). Up to now, this programme has included four intercomparisons for whole-body dosemeters in photon fields, one for extremity dosemeters in photon and beta fields, and one for whole-body dosemeters in neutron fields. Other EURADOS working groups have organised additional intercomparisons including events in 2014 for eye-lens dosemeters and passive area dosemeters for environmental monitoring. In this paper, the organisation and achievements of these intercomparisons are compared in detail focusing on the similarities and differences in their execution. (authors)