Investigation of the spectrally resolved TL signals of natural quartz single crystals sensitized by high-dose of gamma-radiation and moderate heat-treatments

Comparing the monochromatic TL response of a high sensitivity natural quartz irradiated with β and γ rays

“…As noted in Figure 2(b), an increase in TL signal above 350 °C is not observed with the other γ source, being observed only with minor dose-rate of the 137 Cs source. This remarkable increase in the TL signal was previously observed with test-dose of 1 mGy ( 137 Cs) in ReS samples and it was associated with deep traps [16]. Thus, this behavior seems to be much more associated with the magnitude of the dose rate than the radiation source itself.…”

“…For the ReS samples, the figures 3(d, e, f) show that the first peak can be adjusted by a single component whereas the sensitized peak is composed of two components. The presence of the 5 th component at 335 °C was supported by the TL measurements carried out in samples irradiated with test-dose of 1 mGy [16]. Note that for both sources with the highest dose-rate ( 90 Sr/ 90 Y and 60 Co), the sixth component appears with maxima at approximately 420 °C.…”

“…The TL curves were acquired with a combination of interference filters, Schott-BG 39 and AHF-HC 414/46, that corresponds to a violet detection window centered in the 411(51) nm. This filter set is the most adequate to register the TL signals in the whole temperature range for this sample [16].…”

“…On turn, Sunta, Yoshimira and Okuno [22] suggested that the first order kinetics prevails in quartz TL emissions is related to the presence of interactive deep traps. In our previous studies with high sensitive quartz, the TL mechanism was tentatively explained considering the existence of localized transitions of ionic and electronic charges between active electron-hole traps and the existence of deep traps acting ans competitors [14,16]. Due to these reasons, only the first order kinectis was used to model the TL curves in this work.…”

“…Based on the TL glow curves obtained with very small test-dose (1 mGy) [16] and the initial set of fits, six components were established as well as the peak temperatures that best fit all TL curves. The deconvolution procedure consisted of the following steps: (i) include the heating rate; (ii) stipulate the initial values of the fit (amount of peaks, temperature associated with the maximum intensity of each peak); (iii) fix the temperature of the peaks except the first peak TL, which could be freely adjusted by Glowfit; (iv) restrict the variation of the activation energy with increasing temperature, i.e., the activation energy can only have increasing values with the increasing the peak maxima (Tm) of each peak.…”