Abstract Europium doped potassium strontium iodide is a very promising scintillator for national security applications due to its ease of growth and excellent scintillation properties. For this work the fast crystal growth and scintillation properties of 1-inch diameter single crystals of KSr 2 I 5 :Eu 2+ (KSI:Eu) were investigated. We focused our efforts on optimizing the growth parameters required to produce one-inch diameter crystals without decreasing the previously reported fast pulling rate of 5 mm/h. Cracking was minimized by replacing the quartz ampoules with carbon coated quartz ampoules; thus, several crack free single crystals of KSI with varying Eu 2+ concentrations were grown, including a O 1″ by 6″ long boule with 2.5% Eu. The maximum achievable performance of each crystal was measured using small 0.012 cm 3 specimens. The volumetric dependencies of the light yield, energy resolution and decay time were evaluated using KSI:Eu 2% specimens with volumes ranging from 0.012 cm 3 to 18 cm 3 . For large volumes (≥ 9 cm 3 ), the performance was comparable to other high performing scintillators, with light yields up to 78,200 ph/MeV and energy resolutions as good as 3.2% at 662 keV. The initial version of a hermetic package has been developed, and the stability of the sealed crystal is promising.

中文翻译：

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探索 KSr 2 I 5 :Eu 闪烁体晶体 II：Ø 25 mm 晶体的生长条件和 Eu 2+ 浓度效应

摘要 掺铕的碘化锶钾由于其易于生长和优良的闪烁特性，是一种非常有前途的国家安全应用闪烁体。对于这项工作，研究了 1 英寸直径 KSr 2 I 5 :Eu 2+ (KSI:Eu) 单晶的快速晶体生长和闪烁特性。我们集中精力优化生产一英寸直径晶体所需的生长参数，同时不降低先前报道的 5 毫米/小时的快速提拉速率。通过用碳涂层石英安瓿代替石英安瓿，裂纹被最小化；因此，生长了几种具有不同 Eu 2+ 浓度的 KSI 无裂纹单晶，包括具有 2.5% Eu 的 O 1" x 6" 长晶锭。使用小型 0.012 cm 3 样品测量每个晶体可达到的最大性能。使用体积范围为 0.012 cm 3 至 18 cm 3 的 KSI:Eu 2% 样品评估光输出、能量分辨率和衰减时间的体积依赖性。对于大体积（≥ 9 cm 3 ），其性能可与其他高性能闪烁体相媲美，光产额高达 78,200 ph/MeV，能量分辨率在 662 keV 时高达 3.2%。密封封装的初始版本已经开发出来，密封晶体的稳定性很有希望。