Glow peak temperature, supralinearity and LET dependence of TLDs--correlation studies.

The study of the well separated low and high temperature glow peaks in CaSO4:Dy and CaF2:Tm was undertaken to develop comparative data on supralinearity of low and high temperature glow peaks for their use in the estimation of elapsed time of exposure and to analyse their responses to low and high-linear energy transfer (LET) radiation. In CaSO4:Dy, unlike its dosimetric peak, the structure of glow peaks at approximately 140 and 400 degrees C remains unchanged (peak position changes within 4 degrees C) with 60Co gamma-ray exposure up to 1 kGy air kerma. The glow peaks at 140 degrees C exhibited higher supralinearity than that of the peaks at 240 and 400 degrees C. In CaF2:Tm, 110 degrees C glow peak exhibited higher supralinearity and higher response to high-LET radiation as compared with 150 degrees C glow peak. No correlation between glow peak temperature and supralinearity or the LET response was observed.