Investigation of scintillation characteristics for CsI:TI and Nal:TI crystals under different surface treatment conditions

Abstract

The influence of mechanical and chemical methods of CsI:TI and Nal:TI crystals surface treatment on their scintillation characteristics at registration of short-range ionizing radiation has been investigated. It is shown that application of ultrathin silicon dioxide powder obtained by sol-gel method and organosilicon liquids at the polishing stage provides the near-surface layer of CsI:TI and NaI:TI crystals with minimum light yield nonuniformity. After grinding of the crystal surface, the stability of scintillation characteristics can be achieved by the surface treatment with tetraethoxy silane and oligo-(siloxane hydride) liquid. Application of thin-film organosilicon coating on the CsI:TI crystal surface turned to the radiation source has improved the pulse-height resolution by 3-5 % in the absolute value at registration of X-ray radiation with E = 5.9 keV.