2023/12/19 by Muping Chen, Graciela B. Gelmini, Chen, Muping +5 · 1 citation
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #Cosmology and Gravitation Theories
paper · pdf · doi:10.48550/arxiv.2312.12136
Sterile neutrinos (νss) 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 νss 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 νs production mechanisms, this novel mechanism does not depend on the active-sterile mixing. The resulting νss have a distinctive spectrum and are produced with larger energies than in typical scenarios. This characteristic enables νss 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 νs decays constitutes a distinct signature of our scenario. constitutes a distinct signature of our scenario.