Sterile neutrinos (ν _s s) are well-motivated and actively searched for hypothetical neutral particles that would mix with the Standard Model active neutrinos. They are considered prime warm dark matter (DM) candidates, typically when their mass is in the keV range, although they can also be hot or cold DM components. We discuss in detail the characteristics and phenomenology of ν _s s that minimally couple only to active neutrinos and are produced in the evaporation of early Universe primordial black holes (PBHs), a process we called “PBH sterile neutrinogenesis”. Contrary to the previously studied ν_s production mechanisms, this novel mechanism does not depend on the active-sterile mixing. The resulting ν _s s have a distinctive spectrum and are produced with larger energies than in typical scenarios. This characteristic enables ν _s s to be WDM in the unusual 0.3 MeV to 0.3 TeV mass range, if PBHs do not matter-dominate the Universe before evaporating. When PBHs matter-dominate before evaporating, the possible coincidence of induced gravitational waves associated with PBH evaporation and astrophysical X-ray observations from ν_s decays constitutes a distinct signature of our scenario.

中文翻译：

---

原初黑洞惰性中微子发生：惰性中微子暗物质的产生与耦合无关


惰性中微子（ ν _s s) 积极主动地寻找可能与标准模型活性中微子混合的假设中性粒子。通常当它们的质量在 keV 范围内时，它们被认为是主要的暖暗物质 (DM) 候选者，尽管它们也可以是热或冷的 DM 成分。我们详细讨论了特征和现象学ν _s它们只与活跃中微子最低限度地耦合，并在早期宇宙原始黑洞（PBH）蒸发时产生，我们将这一过程称为“PBH惰性中微子发生”。与之前研究的相反_νs生产机制，这种新颖的机制不依赖于活性无菌混合。所结果的ν _s其具有独特的光谱，并且产生的能量比典型情况下更大。这一特性使得ν _s如果 PBH 在蒸发之前不是物质主宰宇宙的话，那么在不寻常的 0.3 MeV 到 0.3 TeV 质量范围内就会成为 WDM。当 PBH 在蒸发前以物质为主时，与 PBH 蒸发相关的感应引力波和天体物理 X 射线观测可能是一致的。 _νs衰变构成了我们场景的独特特征。