D.K. Koul

An attempt to estimate firing temperature using OSL pre-dose sensitization of quartz

The estimation of firing temperature of ceramics using methods based on pre-dose sensitization of the 110°C TL peak of quartz have yielded incoherent results. Recently the fast component of the CW-OSL of quartz has been observed to have pre-dose characteristics similar to that of the 110°C TL peak. The motivation for this study has been to look into the feasibility of this signal, the OSL counter part of pre-dosed TL emission, for the firing temperature identification. The variation in the sensitization ratio of the TL and OSL emissions with different heating temperatures was also utilized to unveil the firing temperature mark of the specimen.

Influence of in Situ Temperature on the Sensitization of Quartz: A Simulation Study

Abstract The influence of ambient geological and burial temperatures, prevailing in nature, on the charge population of the defect centers and, eventually, the sensitivity of the luminescence emission of quartz was simulated using empirical model. Various permutation and combination of these tem-peratures were incorporated so as to observe, both, the collective and independent impact of these two temperatures on the charge kinetics. The results of seem to demonstrate the role of the ambient tem-perature in the sensitization of quartz mineral

Impact of firing on the optically stimulated luminescence of geological quartz

The thermal firing at 800°C of a geological quartz specimen was observed to alter the optically stimulated luminescence (OSL) and thermoluminescence (TL) characteristics of this natural mineral. The variation of the OSL with various pre-heating temperatures suggested the involvement of deep, non-conventional, traps in its production.

Some novel features of post-500°C heating blue stimulated OSL emission of fired natural quartz

Abstract In this study, some novel features of the post 500°C blue stimulated optically stimulated luminescence (OSL) of fired geological quartz are reported. Different observations (i) pulse annealing and (ii) impact of bleaching on high temperature TL glow peak suggested 510°C (heating rate of 2°C/s) TL peak trap to be responsible for the observed emission. The dosimetric properties of this emission were seen to make its applicability for dose assessment till kGy range. The signal was seen to be easily bleachable, reaching background value within 100 s with blue light at 125°C. The signal qualified all the tests (i) reproducibility, (ii) negligible recuperation and (iii) accuracy of dose recovery needed for reliable assessment of the radiation dose with modified Single aliquot regenerative (SAR) protocol. Considering the bleachability and high dynamic dose range of this signal, it has the potential to stretch the upper dose limit of dating by one order of magnitude than possible with conventional OSL, corresponding to 325°C TL trap. So, combining all the results, the signal reported here could be very useful for dosimetric applications involving measurement of high radiation dose, like dating.