The Luminescent Decay of Various Crystals for Particles of Different Ionization Density

Abstract

New measurements of the decay of the luminescence produced in LiI(Eu), NaI(Tl), KI(Tl), CsBr(Tl) and three CsI crystals of varying thallium concentration have been made for particles with different ionization densities. The decay time of the luminescence is found to depend on the average ionization density ρ. In all cases except LiI(Eu) two components are found in the decay. The dependence of the decay times and efficiency, the relative voltage pulse height per unit energy, on thallium concentration for different particles has been studied in CsI. The ratio ρe'/ρα' has been found to increase with the average Z of the crystal where ρe' and ρα' are the average decay times for electrons and alpha particles respectively.