It has been proposed that two resonances could coincide in the early universe at temperatures $T \sim 0.2 ... 0.5$ GeV: one between two nearly degenerate GeV-scale sterile neutrinos, producing a large lepton asymmetry through freeze-out and decays; another between medium-modified active neutrinos and keV-scale sterile neutrinos, converting the lepton asymmetry into dark matter. Making use of a framework which tracks three sterile neutrinos of both helicities as well as three separate lepton asymmetries, and scanning the parameter space of the GeV-scale species, we establish the degree of fine-tuning that is needed for realizing this scenario.

中文翻译：

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通过重合共振的无菌中微子暗物质

有人提出，在早期宇宙中，两个共振可能在温度 $T \sim 0.2 ... 0.5 $ GeV 中重合：两个几乎退化的 GeV 级惰性中微子之间的一个，通过冻结和衰变产生大的轻子不对称性；另一种介于中等修饰活性中微子和 keV 级惰性中微子之间，将轻子不对称性转化为暗物质。利用一个跟踪三个螺旋的惰性中微子以及三个独立的轻子不对称性的框架，并扫描 GeV 尺度物种的参数空间，我们建立了实现这种情况所需的微调程度。