Luminescence and scintillation properties of Na-activated CsI-CsBr crystals

摘要

Scintillation properties, excitation, photo- and radioluminescence spectra of CsI(Na) and CsI-CsBr(Na) crystals containing from 0.5 x 10(-2) to 3.0 x 10(-2) mol% NaI are studied at 300 and 85 K. Based on a comparison of the luminescence characteristics (measured at 85 K) and the scintillation properties of both crystal types, it is shown that the presence of Br impurity in CsI(Na) crystals favors the incorporation of Na into the CsI lattice and hinders the formation of complex centers and activator aggregation. As a result, the CsI-CsBr(Na) crystal surface becomes resistant to atmospheric factors and the energy resolution of CsI-CsBr(Na) based detectors is comparable to that of NaI(Tl) crystals. (C) 2001 Elsevier Science Ltd. All rights reserved. [References: 6]