Title :
Dependence of scintillation characteristics in the CsI(Tl) crystal on Tl+ concentrations under electron and alpha particles excitations
Author :
Hamada, Margarida M. ; Costa, Fabio E. ; Pereira, Maria C C ; Kubota, Shinzou
Author_Institution :
CNEN, Inst. de Pesquisas Energeticas e Nucl., Sao Paulo, Brazil
fDate :
8/1/2001 12:00:00 AM
Abstract :
This paper reports the emission spectra, pulse heights, and decay curves of CsI(TI) crystals with a Tl+ concentration ranging from 10-6 to 10-2 mol under electron and alpha particle excitations. Larger pulse heights from the crystals with Tl+ concentration of more than 10-3 mol were observed for a higher ionization density of alpha particle excitation compared with those of electron excitation. This enhancement may be explained in terms of the higher scintillation efficiency for higher Tl + concentration. Decay curves under electron and alpha particle excitations were compared with the decay curve under pulsed UV excitation. The observed decay curves were explained in terms of the sum of the three energy transfer processes to create excited states (Tl+)*: the prompt process, the Vk diffusion process to Tl0, and the electron release process from Tl0 to Tl++. Here, Tl0 and Tl++ were produced through (Tl++electron)→Tl0 and [Tl++hole (or Vk)]→Tl++
Keywords :
alpha-particle detection; caesium compounds; cathodoluminescence; electron detection; ionoluminescence; scintillation; solid scintillation detectors; thallium; CsI(Tl) crystal; CsI:Tl; Tl+ concentrations; alpha particles excitation; decay curves; diffusion process; electron excitation; electron release process; emission spectra; excited states; ionization density; pulse heights; scintillation characteristics; Alpha particles; Charge carrier processes; Crystals; Diffusion processes; Electron emission; Energy exchange; Ionization; Physics; Pulse measurements; Quantum computing;
Journal_Title :
Nuclear Science, IEEE Transactions on
