Title: Reviving the sterile neutrino dark matter with neutrino secret self-interactions

Speaker: Dr. Manibrata Sen, MPI Heidelberg

Gmeet Link: https://meet.google.com/atn-wjov-pji

Abstract: Sterile neutrinos with masses around a few keV have been postulated to be viable dark matter candidates. This is, however, mostly in tension with various astrophysical observations, the most stringent being the X-ray bounds. In this talk, I would like to present a testable sterile neutrino dark matter production mechanism in the early Universe. The idea is to introduce a light scalar particle that mediates self-interactions among the Standard Model neutrinos. Such interactions enable the sterile neutrinos to be more efficiently produced in the early universe, thus alleviating the tensions and allowing the sterile neutrinos to be perfectly lucrative dark matter candidates. Such secret self-interactions can be tested in future neutrino experiments like DUNE. Apart from laboratory bounds, I will also discuss how these interactions can lead to exciting signatures in the early Universe as well as core-collapse supernovae.