Large Diameter Bulk Crystal Growth and Scintillation Characterization of Thallium-Based Ternary Halide Crystals for Detection and Imaging

TL;DR

This study reports on the growth and characterization of large diameter thallium-based ternary halide crystals, demonstrating their potential for gamma-ray detection and imaging due to high density and good scintillation properties.

Contribution

It presents new growth techniques and performance data for several large thallium-based halide crystals, including doped variants, for scintillation applications.

Findings

TlMgCl3 shows the best crystal quality and energy resolution.

Decay constants range from 0.45 to 0.55 microseconds.

Crystals exhibit linear gamma-ray response above 100 keV.

Abstract

Scintillators cover an important wide range of applications in detection and imaging. In this paper we are presenting growth and performance results of several advanced large diameter thallium-based ternary halide crystals are presented. Intrinsic crystals of TlMgCl3, TlCaCl3, TlCaBr3, and TlCa(Cl,Br)3, as well as europium-doped TlCa2Br5 and TlCa(Cl,Br)3 are melt-grown by the Bridgman method. These compounds have high Zeff due to thallium and expected to have high physical densities. The best crystal quality and energy resolution (FWHM) at 662 keV are observed for intrinsic TlMgCl3. The primary decay constants for these compounds are in the range of 0.45 to 0.55 microseconds. All of these compounds have proportional or linear response to gamma-ray above 100 keV.