Residual radioactive contaminants of a caesium hafnium chloride (Cs₂HfCl₆) crystal scintillator have been measured in a low background setup at the Gran Sasso National Laboratory of the INFN, Italy. The total alpha activity of the detector is at the level of 7.8(3) mBq/kg. The results of direct studies of the α decay of naturally occurring Hf isotopes that have been performed using the “source=detector” approach are presented. In 2848 h of data taking, the α decay of ¹⁷⁴Hf was observed with T${}_{1/2}=(7.0\pm 1.2)\times {10}^{16}$ y.

中文翻译：

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使用Cs ₂ HfCl ₆闪烁体搜索自然存在的Hf核素的α衰变

在意大利INFN的Gran Sasso国家实验室的低背景环境中测量了氯化铯ha（Cs ₂ HfCl ₆）闪烁体的残留放射性污染物。检测器的总α活性为7.8（3）mBq / kg。提出了使用“源=检测器”方法对天然存在的Hf同位素的α衰变进行直接研究的结果。在2848 h的数据采集中，使用T观测到¹⁷⁴ Hf的α衰减${}_{\mathrm{1个}/2}=（7.0\pm 1.2）\times {10}^{16}$ y。