论文标题
$^7 $ be $ l/k $捕获比率的直接测量在基于TA的超导隧道连接
Direct measurement of the $^7$Be $L/K$ capture ratio in Ta-based superconducting tunnel junctions
论文作者
论文摘要
我们报告了$^7 $的$ l/k $轨道电子捕获（EC）比率的高统计测量值嵌入了低温TA中。薄TA膜形成了高分辨率超导隧道连接（STJ）辐射探测器的一部分，该探测器用于识别来自不同衰减通道的信号。测得的$ L/K $捕获比为0.070（7）明显大于此数量的唯一测量和包括中等效应的理论预测。该值是与核与核和原子物理学以及Novae和其他天体物理场景中的LI产生的1S和2S轨道重叠的独特敏感探针。这是第一个使用STJ进行核能检测的实验，为使用稀有同位素开放了一种新的实验途径，用于低能精度测量。
We report a high-statistics measurement of the $L/K$ orbital electron capture (EC) ratio in $^7$Be embedded in cryogenic Ta. The thin Ta film formed part of a high-resolution superconducting tunnel junction (STJ) radiation detector that was used to identify the signals from different decay channels. The measured $L/K$ capture ratio of 0.070(7) is significantly larger than the only previous measurement of this quantity and the theoretical predictions that include in-medium effects. This value is a uniquely sensitive probe of the 1s and 2s orbital overlaps with the nucleus, and is of relevance to nuclear and atomic physics, as well as Li production in novae and other astrophysical scenarios. This is the first experiment that uses STJs for nuclear-recoil detection, opening a new experimental avenue for low-energy precision measurements with rare isotopes.
