Improved scintillation proportionality and energy resolution of LaBr3LaBr_3:Ce at 80 K

Using highly monochromatic synchrotron X-rays in the energy range from 10.5 keV to 100 keV the temperature dependence of nonproportionality and energy resolution of LaBr3 scintillators doped with 5% Ce3+ were studied at 80K, 295K, and 450K. Improvement of the proportionality and better energy resolution was observed on lowering the temperature. This effect suggests that the already outstanding energy resolution of LaBr3:Ce can be improved even further. It also may provide new clues to better understand the processes that cause nonproportionality of inorganic scintillator response.Comment: 5 pages, 2 figures submitted for publication at Nucl. Instr. Meth.