Temperature dependence of luminescence from scintillator LSO:Ce under VUV excitation

Abstract

Luminescence properties of LSO:Ce, including the excitation spectra in 130–370 nm and the emission spectra in 350–500 nm as well as decay times were studied by synchrotron radiation at different temperature between 79 and 295 K. The temperature dependence of the VUV (178 nm) excitation band was different from that of the UV (264, 296 and 364 nm) ones of LSO:Ce luminescence (436 nm). The former had no thermo-quenching and the latter thermo-quenching was evident for both single crystal and powder sample. Not only the excitation spectra, but also the VUV excited emission spectra showed a temperature dependent behavior. The difference can be ascribed to a different energy transfer process in the LSO:Ce material under VUV and UV excitation. When the temperature rises from 79 to 295 K, the VUV excited luminescence decay times vary in the range of 27.6–32.4 ns for single crystal and from 29.8 to 25.5 ns for powder sample.