New scintillator compositions

摘要

Single crystals of LaBr_3:1% Pr and CeBr_3:1% Pr have been grown by the vertical Bridgman technique. Crystals of these scintillators can be used in the fabrication of gamma-ray spectrometers. The LaBr_3:1% Pr and CeBr_3:1% Pr crystals we have grown had light outputs of ～73,000 and ～50,000 photons/MeV, respectively, and principal decay constants of 11 μs and 26 ns, respectively. There were a number of emission peaks observed for these compounds. The emission wavelength range for the LaBr_3:1% Pr and CeBr_3:1% Pr scintillators were from about 400 to 800 nm. The CeBr_3:1% Pr scintillator had a dominating emission peak due to CeBr_3 at 390 nm. These two materials had energy resolutions of 9 and 7% FWHM, respectively, for 662 keV photons at room temperature. In this paper, we will report on our results to date for vertical Bridgman crystal growth and characterization of Pr-doped LaBr_3 and Pr-doped CeBr_3 crystals. We will also describe the special handling and processing procedures developed for these scintillator compositions.