We investigate a consistent scenario of time-varying neutrino masses, and discuss its impact on cosmology, beta decay, and neutrino oscillation experiments. Such time-varying masses are assumed to be generated by the coupling between a sterile neutrino and an ultralight scalar field, which in turn affects the light neutrinos by mixing. We demonstrate how various cosmological bounds, such as those coming from big bang nucleosynthesis, the cosmic microwave background, as well as large scale structures, can be evaded in this model. This scenario can be further constrained using multiple terrestrial experiments. In particular, for beta-decay experiments like KATRIN, nontrivial distortions to the electron spectrum can be induced, even when time-variation is fast and it gets averaged. Furthermore, the presence of time-varying masses of sterile neutrinos will alter the interpretation of light sterile neutrino parameter space in the context of the reactor and gallium anomalies. In addition, we also study the impact of such time-varying neutrino masses on results from the BEST collaboration, which have recently strengthened the gallium anomaly. If confirmed, we find that the time-varying neutrino mass hypothesis could give a better fit to the recent BEST data.

中文翻译：

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通过无菌中微子门户对宇宙学友好的时变中微子质量

我们研究了随时间变化的中微子质量的一致情景，并讨论了它对宇宙学、β衰变和中微子振荡实验的影响。假设这种随时间变化的质量是由无菌中微子和超轻标量场之间的耦合产生的，这反过来又通过混合影响轻中微子。我们展示了如何在这个模型中避开各种宇宙学界限，例如来自大爆炸核合成的那些、宇宙微波背景以及大尺度结构。可以使用多个地面实验进一步限制这种情况。特别是，对于像 KATRIN 这样的 β 衰变实验，即使时间变化很快并且被平均，也可以引起电子光谱的非平凡失真。此外，随时间变化的无菌中微子质量的存在将改变在反应堆和镓异常情况下对轻无菌中微子参数空间的解释。此外，我们还研究了这种随时间变化的中微子质量对 BEST 合作结果的影响，最近加强了镓异常。如果得到证实，我们发现时变中微子质量假说可以更好地拟合最近的 BEST 数据。