STUDY OF COMPTON ELECTRONS IN HALIDE SCINTILLATORS USING CCT

Abstract

Cerium doped Lanthanum halide scintillators are applicable in gamma ray spectroscopy and other applications on a vast scale due to their excellent energy resolution and high stopping power. Present work is based on a technique which is well known as Compton Coincidence Technique (CCT). It was proposed by Valentine and Rooney in 1994, to measure the intrinsic energy resolution of scintillating material. We measured the intrinsic resolution of Compton electron in 3 different scintillators, namely, 1″ × 1″ cylindrical Lanthanum halides (LaBr3:Ce, LaCl3:Ce) and 2"×2" NaI:Tl detector with HPGe as a reference detector. Intrinsic energy resolution was measured by the advanced digital data acquisition system PIXIE-4 which makes the whole measurement setup quite compact having inbuilt spectroscopic amplifier. To measure the intrinsic energy resolution of these scintillators, we have employed the Wide Angle Compton Coincidence Technique (WACCT) for an energy range from 45 keV up to 1.33 MeV. The obtained results shows that nonproportionality is a major reason of entire energy resolution of these halide scintillators and intrinsic resolution mainly arises due to scattering of electrons inside the scintillators. The effect of variation of energy resolution with energy gating width was also measured to optimize its value for a particular detector