Thermoluminescence of Photostimulable Materials after X Irradiation below Room Temperature

Thermoluminescence glow peaks in the temperature range 100 to 400 K are investigated for BaFX (X = Cl, Br) crystals after X irradiation at 100 K. A prominent glow peak of BaFCI around 210 K is found to be composed of a few recombination roots, that is, the peak corresponds to the recombination of hole trapped centres such as an O - centre and a dissociated Cl 2 - centre with the F (F - ) centre and the O 2- -F(Cl - ) pair defect. Another small glow peak around 270 K is likely to occur from thermal dissociation of the O 2- -F(Cl - ) pair defect. The main glow peak of BaFBr:O 2- at 170 K may be attributed to a recombination of an O - centre with the F(Br - ) centre.