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. These new interactions are stronger than the weak interactions and hence can be tested in future neutrino experiments. Apart from laboratory bounds, these interactions also lead to exciting signatures in the early Universe as well as core-collapse supernovae.
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