论文标题
硅的宇宙激活
Cosmogenic activation of silicon
论文作者
论文摘要
$^{3} $ h，$^{7} $和$^{22} $ na通过与硅的交互作用可以在用于搜索罕见事件的探测器中产生放射性背景。通过对硅CCD和晶圆的受控辐照，具有模仿宇宙中子中子光谱的中子光束，然后直接计数，我们确定海平面的宇宙射线中子的生产率为（$ 112 \ pm 24 $ 24 $）/（kg day）的原子（kg Day），$^{3} $ h（$ 8.1 $ h（$ 8.1）（$ 8.1 $ 1.9） $^{7} $ be和（$ 43.0 \ pm 7.1 $）aroms/（kg day）$^{22} $ na。通过当前对中子以外的宇宙射线颗粒激活横截面的最佳估计来补充这些结果，我们获得了$^{3} $ h，（$^{3} $ h，（$ 9.4 \ pm 2.0 $ pm 2.0 \ pm^$ be）的$^{3} $^$^$^$^的总宇宙射线生产率（$ 124 \ pm 24 $）原子/（kg 24 $）atoms/（kg day）， 7.3 $）原子/（kg day）$^{22} $ na。这些测量结果将有助于限制背景估计，并确定在探测器制造过程中基于硅的最大探测器可以在宇宙源性背景之前保持不变的时间，这会影响下一代稀有事实搜索的灵敏度。
The production of $^{3}$H, $^{7}$Be, and $^{22}$Na by interactions of cosmic-ray particles with silicon can produce radioactive backgrounds in detectors used to search for rare events. Through controlled irradiation of silicon CCDs and wafers with a neutron beam that mimics the cosmic-ray neutron spectrum, followed by direct counting, we determined that the production rate from cosmic-ray neutrons at sea level is ($112 \pm 24$) atoms/(kg day) for $^{3}$H, ($8.1 \pm 1.9 $) atoms/(kg day) for $^{7}$Be, and ($43.0 \pm 7.1 $) atoms/(kg day) for $^{22}$Na. Complementing these results with the current best estimates of activation cross sections for cosmic-ray particles other than neutrons, we obtain a total sea-level cosmic-ray production rate of ($124 \pm 24$) atoms/(kg day) for $^{3}$H, ($9.4 \pm 2.0 $) atoms/(kg day) for $^{7}$Be, and ($49.6 \pm 7.3 $) atoms/(kg day) for $^{22}$Na. These measurements will help constrain background estimates and determine the maximum time that silicon-based detectors can remain unshielded during detector fabrication before cosmogenic backgrounds impact the sensitivity of next-generation rare-event searches.
