Effect of surface of single crystals ZnSe(Te) and Csl(TI) on dynamic characteristics of spectrometric parameters of detection blocks

Evaluation was made of changes in scintillation and dynamic characteristics of detection blocks of 'scintillator- photodiode' type based on crystals ZnSe(Te) and CsI(Tl) after long-term storage of unprotected crystals under normal climatic conditions, as well as after action of water vapor. It is shown that changes of energy resolution of large CsI(Tl) crystal are not significant; only the radiation noise threshold is changed due to the phosphorescence of the disturbed surface layer of the crystal. For single crystals ZnSe(Te), which are used for spectrometry of charged particles and short-range gamma-radiation as thin plates, both dynamic noise threshold and spectrometric characteristics are changed. Possibilities to restore the initial crystal properties are discussed, and ways to protect the crystal surface from environmental effects are considered.