Branching Transport Model of Alkali-Halide Scintillators

TL;DR

This study investigates the scintillation decay dynamics in NaI(Tl) crystals, revealing temperature-dependent nonexponential components linked to carrier transport mechanisms, and models the linear temperature dependence of light output.

Contribution

The paper introduces a branching transport model explaining nonexponential decay components and their temperature dependence in NaI(Tl) scintillators.

Findings

Identified two main nonexponential decay components with Arrhenius temperature dependence.

Demonstrated a linear relationship between temperature and total light output.

Provided a model linking carrier transport mechanisms to scintillation decay behavior.

Abstract

We measure the time dependence of the scintillator light-emission pulses in NaI(Tl) crystals at different temperatures, after activation by gamma rays. We confirm that there are two main nonexponential components to the time decay and find that their amplitude ratio shows Arrhenius temperature dependence. We explain these nonexponential components as arising from two competing mechanisms of carrier transport to the Tl activation levels. The total light output of the NaI(Tl) detectors shows a linear temperature dependence explained by our model.