We present the first measurement of nuclear recoils from solar 8B neutrinos via coherent elastic neutrino-nucleus scattering with the XENONnT dark matter experiment. The central detector of XENONnT is a low-background, two-phase time projection chamber with a 5.9 t sensitive liquid xenon target. A blind analysis with an exposure of 3.51  t×yr resulted in 37 observed events above 0.5 keV, with (26.4+1.4−1.3) events expected from backgrounds. The background-only hypothesis is rejected with a statistical significance of 2.73⁢𝜎. The measured 8B solar neutrino flux of (4.7+3.6−2.3)×106  cm−2 s−1 is consistent with results from the Sudbury Neutrino Observatory. The measured neutrino flux-weighted CE⁢𝜈⁢NS cross section on Xe of (1.1+0.8−0.5)×10−39  cm2 is consistent with the Standard Model prediction. This is the first direct measurement of nuclear recoils from solar neutrinos with a dark matter detector.

中文翻译：

---

通过 XENONnT 的相干弹性中微子-核散射发现 Solar8BNeutrinos 的第一个迹象


我们首次通过 XENONnT 暗物质实验通过相干弹性中微子-核散射测量了太阳 8B 中微子的核反冲。XENONnT 的中心探测器是一个低本底、两相时间投影室，带有一个 5.9 t 敏感的液体氙靶。暴露量为 3.51 t×yr 的盲法分析导致 37 个观察到的事件高于 0.5 keV，其中 （26.4+1.4−1.3） 个事件预期来自背景。仅背景假设被拒绝，统计显著性为 2.73σ。测得的 8B 太阳中微子通量为 （4.7+3.6−2.3）×106 cm−2 s−1 与萨德伯里中微子天文台的结果一致。测得的中微子通量加权 CEνNS 在 Xe 上的横截面为 （1.1+0.8−0.5）×10−39 cm2 与标准模型预测一致。这是首次使用暗物质探测器直接测量太阳中微子的核反冲。