2021/04/30 by Maíra Dutra, Vinícius Oliveira, C. A. de S. Pires +1 · 1 citation
Physics and Astronomy · #hep-ph #astro-ph.HE #hep-th
paper · pdf · doi:10.1007/jhep10(2021)005
23 pages, 4 figures. References added, matches published version
arxiv created 2021/10/12 · arxiv updated 2021/10/14
We discuss a model where a mixed warm and hot keV neutrino dark matter rises naturally. We arrange active and sterile neutrinos in the same SU(3)L multiplet, with the lightest sterile neutrino being dark matter. The other two heavy sterile neutrinos, through their out-of-equilibrium decay, contribute both to the dilution of dark matter density and its population, after freeze-out. We show that this model features all ingredients to overcome the overproduction of keV neutrino dark matter, and explore the phenomenological implications for Big Bang Nucleosynthesis and the number of relativistic degrees of freedom.