In this paper, the thermoluminescence (TL) dosimetric characteristics under beta-ray, x-ray and g... more In this paper, the thermoluminescence (TL) dosimetric characteristics under beta-ray, x-ray and gamma-ray excitations of powder and pellet Mn-doped lithium tetraborates (LTB) which were produced by solution combustion synthesis technique were investigated, and the results were compared with that of TLD-100 chips. The chemical composition and morphologies of the obtained LTB and Mn-doped LTB (LTB: Mn) were confirmed by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM) with EDX. LTB:Mn was studied using luminescence spectroscopy. In addition, the effects of sintering and annealing temperatures and times on the thermoluminescence (TL) properties of LTB:Mn were investigated. The glow curves of powder samples as well as pellet samples exposed to different beta doses exhibited a low temperature peak at about 100 °C followed by an intense principal high temperature peak at about 260 °C. The kinetic parameters (E, b, s) associated with the prominent glow peaks were estimated using T m –T stop , initial rise (IR) and computerized glow curve deconvolution (CGCD) methods. The TL response of integral TL output increased linearly with increasing the dose in the range of 0.1–10 Gy and was followed by a superlinearity up to 100 Gy both for powder and pellet samples using beta-rays. Powder and pellet LTB:Mn were irradiated to a known dose by a linear accelerator with 6 and 18 MV photon beams, 6–15 MeV electron beams and a traceable 137 Cs beam to investigate energy response. Further, TL sensitivity, fading properties and recycling effects related with beta exposure of LTB:Mn phosphor were evaluated and its relative energy response was also compared with that of TLD-100 chips. The comparison of the results showed that the obtained phosphors have good TL dose response with adequate sensitivity and linearity for the measurement of medical doses.
Oluşumunu tamamlamış kayaçlarm ısı ve basınç etkisiyle değişime uğraması olayına “metamorfîzma” v... more Oluşumunu tamamlamış kayaçlarm ısı ve basınç etkisiyle değişime uğraması olayına “metamorfîzma” ve bu yolla oluşan kayaçlara ise “metamorfik kayaçlar” adı verilir. Metamorfik kayaçlar genel olarak tortul kayaçlar ve magmatik kayaçlardan oluşmaktadır. Metamorfik kuvarslar metamorfik kayaç türlerinden biri olup tortul kökenli kuvarsların metamorfızmaya uğramasıyla oluşur. Bu çalışmada. Türkiye ve İspanya kaynaklı metamorfik kuvarsların (TMQ ve SMQ) doz yanıtları test edilerek her iki ülkeye ait örneklerin doz yanıtları karşılaştırılmıştır. Çalışmada kullanılan TMQ ve SMQ örnekleri 90 ile 140 um arasındaki parçacık boyutlarında elendikten sonra RisoTL/OSL DA-20 model termolüminesans (TL) ölçüm sisteminde 90Sr/90Y (3-kaynağı ile 6.689 Gy ile 4.816 Gy arasında ışmlanmıştır. Işınlama işlemlerinden sonra TL ölçümleri, örneklerin 125°C‘de 15 s süre ile ön ısıtmaya tabi tutularak 2°C/s ısıtma hızıyla oda sıcaklığından 600°C’ye kadar ısıtılmasıyla yapılmıştır. Ölçümler sonucunda kaydedilen TL...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2015
In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appear... more In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir-Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450°C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by 90 Sr/ 90 Y beta particles.
In this study the dosimetric characteristics of some natural hydrothermal quartz (NHQ) samples co... more In this study the dosimetric characteristics of some natural hydrothermal quartz (NHQ) samples collected from Hakkari were investigated by using the thermoluminescence (TL) technique for the purpose of determining whether they are suitable as dosimetric materials or not and calculating the kinetic parameters. The experiments carried out can be outlined as: analyzing TL glow curves of NHQ; determining the annealing conditions; the effects of pre-irradiation annealing procedures on TL sensitivity; the investigation of the characteristics of TL glow curves obtained after annealing the samples; determination of the trap parameters with the computerized glow curve deconvolution (CGCD) method and the peak shape (PS) method. The obtained results showed that the trap depths and the frequency factor values are consistent with the literature. The studied samples have linear dose responses for the absorbed doses ranging between $ 6.689 Gy and $ 301 Gy. In conclusion, the examined quartz samples can be used as dosimetric materials in high dose applications.
In this study, the various dosimetric properties of the thermoluminescent (TL) phosphor of CaF 2 ... more In this study, the various dosimetric properties of the thermoluminescent (TL) phosphor of CaF 2 :natural including response characteristics, sensitivity to thermal annealing and decay of stored energy were investigated in detail. The analysis of the peak temperature values and the half widths of the resolved components in the glow curves, by using the Computerized Glow Curve Deconvolution (CGCD) Method, resulted in the activation energy (E) of 0.85e1.83 eV and frequency factor (s) of 6.17Eþ9e2.90Eþ15 s À1 . The effects of pre-irradiation thermal annealing on the radiation-induced sensitization of the thermoluminescent response of CaF 2 :natural were presented. An enhancement of sensitivity after being subjected to a high beta particle exposure was clarified. The effect was complicated by the influence of heat treatments before the exposure to radiation. Replicate runs on CaF 2 :natural after irradiation with 1 Gy absorbed dose indicated good reproducibility of peak temperatures and intensities; they can be re-used for repeated measurements. It appeared that the main dosimetric peak at 280 C exhibits negligible fading over 4 weeks and may be used for dosimetry. This study has demonstrated that the potential exists for the use of CaF 2 :natural for TL radiation dosimetry.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2009
The characteristics of natural calcium fluoride from Çiçekdagı Massif (Akçakent) in Turkey have b... more The characteristics of natural calcium fluoride from Çiçekdagı Massif (Akçakent) in Turkey have been studied by analysing its thermoluminescence glow curve structure between 30 and 450°C for the purpose of radiation dosimetry. A variety of thermoluminescence measurement regimes have been examined to determine the most effective and appropriate annealing temperature, heating rate and dose range for the proper and accurate use of this phosphorescent material. After a high temperature annealing as TL readings, optimum values for low temperature annealing and heating rate were obtained as 60°C for 24 h and 1°C s À1 , respectively. In the dose range of 0.5 Gy-1 kGy, the intensity of individual glow peaks and overall glow curve shape changed. The peak intensities of all glow curves located at 100 and 120°C (overlapping considerably), and at 215°C, at 310, 350 and 410°C (overlapping) increase linearly with increasing ionizing radiation over a range of from 0.5 Gy to 10 Gy.
In this paper, the thermoluminescence (TL) dosimetric characteristics under beta-ray, x-ray and g... more In this paper, the thermoluminescence (TL) dosimetric characteristics under beta-ray, x-ray and gamma-ray excitations of powder and pellet Mn-doped lithium tetraborates (LTB) which were produced by solution combustion synthesis technique were investigated, and the results were compared with that of TLD-100 chips. The chemical composition and morphologies of the obtained LTB and Mn-doped LTB (LTB: Mn) were confirmed by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM) with EDX. LTB:Mn was studied using luminescence spectroscopy. In addition, the effects of sintering and annealing temperatures and times on the thermoluminescence (TL) properties of LTB:Mn were investigated. The glow curves of powder samples as well as pellet samples exposed to different beta doses exhibited a low temperature peak at about 100 °C followed by an intense principal high temperature peak at about 260 °C. The kinetic parameters (E, b, s) associated with the prominent glow peaks were estimated using T m –T stop , initial rise (IR) and computerized glow curve deconvolution (CGCD) methods. The TL response of integral TL output increased linearly with increasing the dose in the range of 0.1–10 Gy and was followed by a superlinearity up to 100 Gy both for powder and pellet samples using beta-rays. Powder and pellet LTB:Mn were irradiated to a known dose by a linear accelerator with 6 and 18 MV photon beams, 6–15 MeV electron beams and a traceable 137 Cs beam to investigate energy response. Further, TL sensitivity, fading properties and recycling effects related with beta exposure of LTB:Mn phosphor were evaluated and its relative energy response was also compared with that of TLD-100 chips. The comparison of the results showed that the obtained phosphors have good TL dose response with adequate sensitivity and linearity for the measurement of medical doses.
Oluşumunu tamamlamış kayaçlarm ısı ve basınç etkisiyle değişime uğraması olayına “metamorfîzma” v... more Oluşumunu tamamlamış kayaçlarm ısı ve basınç etkisiyle değişime uğraması olayına “metamorfîzma” ve bu yolla oluşan kayaçlara ise “metamorfik kayaçlar” adı verilir. Metamorfik kayaçlar genel olarak tortul kayaçlar ve magmatik kayaçlardan oluşmaktadır. Metamorfik kuvarslar metamorfik kayaç türlerinden biri olup tortul kökenli kuvarsların metamorfızmaya uğramasıyla oluşur. Bu çalışmada. Türkiye ve İspanya kaynaklı metamorfik kuvarsların (TMQ ve SMQ) doz yanıtları test edilerek her iki ülkeye ait örneklerin doz yanıtları karşılaştırılmıştır. Çalışmada kullanılan TMQ ve SMQ örnekleri 90 ile 140 um arasındaki parçacık boyutlarında elendikten sonra RisoTL/OSL DA-20 model termolüminesans (TL) ölçüm sisteminde 90Sr/90Y (3-kaynağı ile 6.689 Gy ile 4.816 Gy arasında ışmlanmıştır. Işınlama işlemlerinden sonra TL ölçümleri, örneklerin 125°C‘de 15 s süre ile ön ısıtmaya tabi tutularak 2°C/s ısıtma hızıyla oda sıcaklığından 600°C’ye kadar ısıtılmasıyla yapılmıştır. Ölçümler sonucunda kaydedilen TL...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2015
In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appear... more In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir-Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450°C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by 90 Sr/ 90 Y beta particles.
In this study the dosimetric characteristics of some natural hydrothermal quartz (NHQ) samples co... more In this study the dosimetric characteristics of some natural hydrothermal quartz (NHQ) samples collected from Hakkari were investigated by using the thermoluminescence (TL) technique for the purpose of determining whether they are suitable as dosimetric materials or not and calculating the kinetic parameters. The experiments carried out can be outlined as: analyzing TL glow curves of NHQ; determining the annealing conditions; the effects of pre-irradiation annealing procedures on TL sensitivity; the investigation of the characteristics of TL glow curves obtained after annealing the samples; determination of the trap parameters with the computerized glow curve deconvolution (CGCD) method and the peak shape (PS) method. The obtained results showed that the trap depths and the frequency factor values are consistent with the literature. The studied samples have linear dose responses for the absorbed doses ranging between $ 6.689 Gy and $ 301 Gy. In conclusion, the examined quartz samples can be used as dosimetric materials in high dose applications.
In this study, the various dosimetric properties of the thermoluminescent (TL) phosphor of CaF 2 ... more In this study, the various dosimetric properties of the thermoluminescent (TL) phosphor of CaF 2 :natural including response characteristics, sensitivity to thermal annealing and decay of stored energy were investigated in detail. The analysis of the peak temperature values and the half widths of the resolved components in the glow curves, by using the Computerized Glow Curve Deconvolution (CGCD) Method, resulted in the activation energy (E) of 0.85e1.83 eV and frequency factor (s) of 6.17Eþ9e2.90Eþ15 s À1 . The effects of pre-irradiation thermal annealing on the radiation-induced sensitization of the thermoluminescent response of CaF 2 :natural were presented. An enhancement of sensitivity after being subjected to a high beta particle exposure was clarified. The effect was complicated by the influence of heat treatments before the exposure to radiation. Replicate runs on CaF 2 :natural after irradiation with 1 Gy absorbed dose indicated good reproducibility of peak temperatures and intensities; they can be re-used for repeated measurements. It appeared that the main dosimetric peak at 280 C exhibits negligible fading over 4 weeks and may be used for dosimetry. This study has demonstrated that the potential exists for the use of CaF 2 :natural for TL radiation dosimetry.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2009
The characteristics of natural calcium fluoride from Çiçekdagı Massif (Akçakent) in Turkey have b... more The characteristics of natural calcium fluoride from Çiçekdagı Massif (Akçakent) in Turkey have been studied by analysing its thermoluminescence glow curve structure between 30 and 450°C for the purpose of radiation dosimetry. A variety of thermoluminescence measurement regimes have been examined to determine the most effective and appropriate annealing temperature, heating rate and dose range for the proper and accurate use of this phosphorescent material. After a high temperature annealing as TL readings, optimum values for low temperature annealing and heating rate were obtained as 60°C for 24 h and 1°C s À1 , respectively. In the dose range of 0.5 Gy-1 kGy, the intensity of individual glow peaks and overall glow curve shape changed. The peak intensities of all glow curves located at 100 and 120°C (overlapping considerably), and at 215°C, at 310, 350 and 410°C (overlapping) increase linearly with increasing ionizing radiation over a range of from 0.5 Gy to 10 Gy.
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