Responses and Glow Curves of Li2B4O7:Cu,BeO and CaSO4:Tm TLDs to 10-40 keV Monoenergetic Photons from Synchrotron Radiation

Abstract

Energy and dose responses of Li 2 B 4 O 7 :Cu, BeO and CaSO 4 :Tm TLDs were obtained from the glow curves measured for 10-40 keV monoenergetic photons from synchrotron radiation. The energy responses of Li i B 4 O 7 :Cu were 8% to 20% smaller than the ratios of the mass energy absorption coefficients of the TLD to those of air. The dose response was linear up to 650 Gy for 60 Co gamma rays and 300 Gy for 10 keV X rays, which was followed by saturation. On the other hand, the energy responses at BeO and CaSO 4 :Tm became larger than calculated by 70% and 8% to 24%, respectively. For BeO, the glow curves were independent of photon energy, while for CaSO 4 :Tm the ratio of the high temperature peaks was slightly larger for the low energy X rays than 60 Co gamma rays. Furthermore, in the supralinear region the ratio increased with dose for CaSO 4 :Tm, showing that the growth rate and the dose responses were larger for 60 Co gamma rays compared with those for the low energy X rays.