Recent progress in the development of CsI(Tl) crystal-Si-photodiode spectrometric detection assemblies

Highly sensitive spectrometric γ-detection assemblies are developed using a comprehensive approach (optimization of crystal growth conditions as well as of treatment and packing of scintillators, creation of low-noise charge-sensitive preamplifiers and shapers). The detection assemblies with CsI(Tl)⩽100 cm3 have a sensitivity of about 20 pulse/s(mcR/h), their energy resolution with respect to 137Cs γ-line being ⩽8.5%. The assemblies with lesser scintillator volumes (1-5 cm3) provide a resolution lower than 6% with respect to 137Cs and ⩽40% with respect to 241Am.