Freeze-in and freeze-out of sterile neutrino dark matter

Autor: Coy, Rupert, Schmidt, Michael A.
Rok vydání: 2022
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1088/1475-7516/2022/08/070
Popis: A sterile neutrino with a keV-scale mass is a compelling dark matter candidate. We propose a new production mechanism involving the decay and annihilation of a complex scalar singlet with a Higgs portal coupling which develops a vacuum expectation value. The interactions of the resulting pseudo Nambu-Goldstone boson may thermalise the dark sector. We determine the region of parameter space where dark sector thermalisation is reached and discuss the most relevant cosmological observables. The scenario can be considered as the combination of a freeze-in of the dark sector followed by relativistic freeze-out.
Comment: 41 pages, 9 figures; v2: Version accepted by JCAP, extended discussions of sterile neutrino and pNGB couplings and of DM decay channels in section 2, corrected Eqs. 70 and 72, minor modifications to Figs. 6 and 7, typos fixed; results qualitatively unchanged; v3: corrected error in pNGB coupling to neutrinos in Eq. 14 and related discussion; discussion of sterile neutrino DM production unchanged
Databáze: arXiv