论文标题
在Hafnium中寻找稀有和诱发的核衰变
A search for rare and induced nuclear decays in hafnium
论文作者
论文摘要
使用改良的超低背景高纯度检测器对Hafnium Foil进行测量，并在实验室Nazionale del Gran Sasso进行了优化的样品对检测器几何形状。除了对在310天内收集的数据分析以搜索可能发生在天然HF同位素中的稀有过程外，还详细研究了库存HF箔的放射性。首先，所有天然HF同位素对女儿核素的第一个激发状态的α衰变的限制在$ 10^{16} $ -10} $ -10^{18} $ a（90％C.L.）的范围内建立。其次，执行了$^{174} $ hf的正电子捕获模式和电子捕获模式，产生半寿命限制$ 10^{16} $ - $ 10^{18} $ a（90％C.L.）。最后，研究了新型暗物质引起的同位素hafnium同位素的核激发。对于带有1个TEV/$ C^2 $质量的暗物质，对无弹性暗物质的领先限制 - Nucleon横截面设置为在428 kev $ <Δ<Δ<$ 473 kev范围内的质量分裂。
A measurement of hafnium foil using a modified ultra-low-background high purity detector with optimized sample-to-detector geometry was performed at Laboratori Nazionale del Gran Sasso. Radiopurity of the stock Hf foil was studied in detail, in addition to an analysis of data collected over 310 days to search for rare processes that can occur in natural Hf isotopes. Firstly, limits on alpha decays of all natural Hf isotopes to the first excited state of the daughter nuclides were established in the range of $10^{16}$-$10^{18}$a (90% C.L.). Secondly, a search for modes of double electron capture and electron capture with positron emission in $^{174}$Hf was performed, yielding half-life limits $10^{16}$-$10^{18}$a (90% C.L.). Lastly, novel dark matter-induced nuclear excitations in hafnium isotopes were investigated. For dark matter with 1 TeV/$c^2$ mass, leading limits on the inelastic dark matter--nucleon cross section are set for mass splittings in the range 428 keV $< δ<$ 473 keV.
