Sterile neutrinos are natural extensions to the standard model of particle physics and provide a possible portal to the dark sector. We report a new search for the existence of sub-MeV sterile neutrinos using the decay-momentum reconstruction technique in the decay of ${}^7\mathrm{Be}$. The experiment measures the total energy of the ${}^7\mathrm{Li}$ daughter atom from the electron capture decay of ${}^7\mathrm{Be}$ implanted into sensitive superconducting tunnel junction (STJ) quantum sensors. This first experiment presents data from a single STJ operated at a low count rate for a net total of 28 days, and provides exclusion limits on sterile neutrinos in the mass range from 100 to 850 keV that improve upon previous work by up to an order of magnitude.

中文翻译：

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Be7衰变在超导量子传感器中对亚MeV无菌中微子的存在的限制

无菌中微子是粒子物理学标准模型的自然延伸，并为暗区提供了可能的门户。我们报告了使用衰变动量重建技术在衰变过程中寻找亚甲乙型（MeV）无菌中微子的新发现。${}^7是$。实验测量的是${}^7里$ 电子捕获衰变的子原子 ${}^7是$植入敏感的超导隧道结（STJ）量子传感器中。该第一个实验提供了来自单个STJ的数据，该STJ在低计数率下操作了总共28天，并提供了质量范围从100到850 keV的无菌中微子的排除极限，该极限在以前的工作中提高了大约一个数量级。大小。