Thermoluminescence and scintillation properties of LuAP and YAP

In this communication we report on the application of low temperature therm oluminescence (ltTL) associated with shallow traps in the research on scint illation properties of cerium doped LuAP and YAP crystals. We show that exi stence of shallow traps and their interference with the scintillation proce ss readily explain changes in Light yield and time profiles with temperatur e. The analysis of two major glow peaks at 183 and 270 K of LuAP:Ce yields trap parameters: The activation energy E=0.507 eV; the frequency factor s=3 .65x10(12) s(-1) and E=0.786 eV; s=1.77X10(13) s(-1), respectively. A glow curve of YAP:Ce also shows two major glow peaks at 108 K and 154 K, althoug h this case is more complex and involves a distribution in the energies. As suming a Gaussian distribution with the standard deviation sigma congruent to 0.018 eV we find trap parameters to be: E=0.30 eV (the mean); s=5X10(12) s(-1) and E=0.5 eV; s=7X10(14) s(-1) respectively. Then using the obtained trap parameters we calculate examples of time profiles and light yield cha racteristics to compare them to the experimental results. (C) 2000 Publishe d by Elsevier Science S.A. All rights reserved.