O. Guillot-Noel, J. T. M. de Haas, P. Dorenbos, C. W. E. van Eijk, K. Krämer and H. U. Güdel
Optical and scintillation properties of cerium-doped LaCl₃, LuBr₃ and LuCl₃
J. Lumin. 85, 21-35 (1999)                 

Abstract: The optical and scintillation properties of LaCl₃ : 0.57% Ce, LuBr₃ : 0.021%, 0.46%, 0.76% Ce and LuCl₃ : 0.45% Ce are studied under optical, X- and g-ray excitation. The highest light yield of 40000±4000 photons per MeV (ph/MeV) of absorbed g-ray energy was measured for LaCl₃ : 0.57% Ce. An energy resolution (FWHM over peak position) of, respectively, 7.0±0.5%, 6.0±0.1%, 7.8±0.3%, 6.5±0.5% and 18.0±0.5% was observed for the 662 keV full absorption peak. The scintillation decay curves can be described with three components: 20±2, 330±30 ns and 2.2±0.2 ms for LaCl₃ : 0.57%; 32±3, 450_¯550 ns and >5 ms for LuBr₃ : 0.76%; 50±5, 250_¯350 ns and >4 ms for LuCl₃ : 0.45%.