This paper reports on successful growth and performance evaluation of two large diameter Cs2HfCl6 (CHC) and Cs2HfCl4Br2 (CHCB), both recently developed scintillator crystals. The discovery of Cs2HfCl6 (CHC) as a scintillator has lately generated much interest in this material and its family, which belongs to the K2PtCl6 cubic crystal structure. CHC is an intrinsic scintillator that is non-hygroscopic, has no self-radioactivity, provides excellent energy resolution, and has excellent non-proportionality. CHC has a moderate density of 3.9 g/cm3 and an effective atomic number of 58. Reported in this paper are transparent crack-free single crystal CHC and CHCB boules of one inch in diameter, both grown using the vertical Bridgman method. Samples retrieved from the boules, sized 23mm dia. x 30mm and 23mm dia. x 26mm, respectively, are characterized for their optical and scintillation properties. Energy resolutions of 3.5% and 3.7% (FWHM) at 662 keV, respectively, are reported. Results comparable to previously reported results for smaller crystals have been obtained. Studies on light yield, decay time, non-proportionality, as well as detector characterization are also reported.

中文翻译：

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先进的高性能大直径 Cs2HfCl6 (CHC) 和混合卤化物闪烁体

本文报告了最近开发的两种大直径 Cs2HfCl6 (CHC) 和 Cs2HfCl4Br2 (CHCB) 的成功生长和性能评估。Cs2HfCl6 (CHC) 作为闪烁体的发现最近引起了人们对该材料及其家族的极大兴趣，它属于 K2PtCl6 立方晶体结构。CHC 是一种本征闪烁体，不吸湿，没有自放射性，提供出色的能量分辨率，并且具有出色的非比例性。CHC 具有 3.9 g/cm3 的中等密度和 58 的有效原子序数。本文报道的是直径为 1 英寸的透明无裂纹单晶 CHC 和 CHCB 晶锭，均使用垂直布里奇曼方法生长。从晶锭中取出的样品，直径为 23 毫米。x 30 毫米和 23 毫米直径。x 26mm，分别为 以它们的光学和闪烁特性为特征。据报道，在 662 keV 下的能量分辨率分别为 3.5% 和 3.7% (FWHM)。已获得与先前报道的较小晶体结果相当的结果。还报告了对光输出、衰减时间、非比例性以及检测器特性的研究。