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The thermo-stimulated luminescence (TSL) green emission band of natural quartz arenite was studied. The natural glow curve displayed a broad peak with the maximum at ∼288 °C. The gamma (γ)-induced glow curves showed TSL peaks at 70 °C, 90 °C, 135 °C, 220 °C and 320 °C over the dose range of 1-104 Gy. The trap parameters were calculated using the initial rise procedure. The γ-dose vs. TSL response was linear (uncertainty was within±3%) in the dose range of 1-100 Gy, above which sublinearity sets in. For the investigated material, the batch homogeneity has been calculated to be 0.28. Fading studies over a period of 5 days show that the γ-irradiated aliquots have a stable signal of 84%. The results are of importance in TSL dating, nuclear accident dosimetry, industry and for high-dose measurements. [ABSTRACT FROM AUTHOR]

Abstract: The suitability of sandstone for the gamma radiation dosimetry using thermoluminescence technique is investigated. Its properties are systematically studied utilizing atomic absorption spectrometry, measurements of natural and laboratory-induced blue thermoluminescence emission band, trap depths and storage effects. The emission of the natural blue-band exhibited broad peak at ∼315°C. The thermoluminescence gamma dose response has a linear behavior over the dose range 1–50Gy followed by sub-linearity at high dose level, with standard deviation in all cases less than ±9%. Trapping depths showed a closely spaced set of traps for both the natural and laboratory-induced glow curves. The variation in thermoluminescence signal over 1week storage period at room temperature was not more than 7%. The thermoluminescence fading effects were explained by the localized transition model. From our results, it is possible to conclude that natural sandstone is a suitable material for accident and industrial dosimetric applications. [Copyright &y& Elsevier]

Abstract: This research describes preliminary investigation of some radiation dosimetry characteristics of commercial dysprosium fluoride powder. The as-received aliquot has strong thermoluminescence (TL) emission with one sharp peak at ∼234°C. The TL characteristics have been examined under excitation of gamma (γ) doses in the range 1Gy–50kGy from a 60Co gamma source. The dose response was linear up to 100Gy and a sub-linear response was observed at higher doses. The TL signal is observed to remain stable for aliquots irradiated to γ-doses in the range 1–10Gy over one month storage period in dark at ambient temperature and humidity conditions. This paper recommends using DyF3 in doping of TL materials which may be promising for future dosimeter development. [Copyright &y& Elsevier]

Magnesium oxide (MgO) has been investigated as a possible candidate for gamma (γ) dosimetry. One thermoluminescence (TL) peak was observed in the red emission band around 372 °C in the pristine sample. The glow curves indicate that the main TL peaks appear at nearly the same temperatures after γ and ultraviolet irradiations. The dose response has a linear behavior at intermediate dose levels 1-100 Gy, and then becomes sublinear at high dose levels 0.5-50 kGy. The dose dependence of the phototransfer TL signal is recorded in the γ dose range from 0.05 to 50 Gy. Fading studies over a period of 75 days show that the γ-irradiated aliquots faded by 32% when exposed to 1 Gy. Comparison of the results from the present work with those found in the literature shows that differences are sample- and instrument-dependent. The results further predict the potential of MgO as a phosphor in accident and industrial dosimetry taking into consideration the fading effects. [ABSTRACT FROM AUTHOR]

A thermoluminescence phenomenon has been observed in synthetic mica. The pristine sample glow curve provides the presence of TL glow peaks at 210, 260, 275, 300, 330 and 380°C with trap depths of 0.11, 0.46, 0.82, 1.4, 0.61 and 0.54 eV, respectively. The thermal activation energies of these defects were estimated by using the initial rise method. Gamma and electron beam irradiations have induced completely different glow curves in mica, which reveal the presence of other low temperature traps in the range 54-195°C. The TL growth curves reveal the possibility of using the investigated material in accident dosimetry. [ABSTRACT FROM AUTHOR]