论文标题
在SNO+水相中的中子蛋白捕获的测量
Measurement of neutron-proton capture in the SNO+ water phase
论文作者
论文摘要
SNO+实验从2017年9月至2019年7月收集了数据作为低阈值水切伦科夫探测器的数据。使用AM-BEBE校准源对Neutron捕获产生的2.2-MEV $γ$的测量结果与4.4-mev $γ$γ$γ$γ$γ$相同。分析4.4 meV $γ$和2.2 meV捕获$γ$之间的延迟重合,显示了中子检测效率的中心效率约为50%,并且在检测器内部区域的水平上有所不同,据我们所知,这是在纯水水Cherenkov检测器中获得的最高效率。此外,测量中子捕获时间常数并将其转换为$ 336.3^{+1.2} _ { - 1.5} $ MB的热中子蛋白捕获截面。
The SNO+ experiment collected data as a low-threshold water Cherenkov detector from September 2017 to July 2019. Measurements of the 2.2-MeV $γ$ produced by neutron capture on hydrogen have been made using an Am-Be calibration source, for which a large fraction of emitted neutrons are produced simultaneously with a 4.4-MeV $γ$. Analysis of the delayed coincidence between the 4.4-MeV $γ$ and the 2.2-MeV capture $γ$ revealed a neutron detection efficiency that is centered around 50% and varies at the level of 1% across the inner region of the detector, which to our knowledge is the highest efficiency achieved among pure water Cherenkov detectors. In addition, the neutron capture time constant was measured and converted to a thermal neutron-proton capture cross section of $336.3^{+1.2}_{-1.5}$ mb.