MCTP HET BROWN BAG SEMINAR | Not-so-sterile Neutrinos and New Leptonic Interactions

The Standard Model supplemented with three light sterile neutrinos is a well-motivated, minimal model that accounts for dark matter, baryogenesis, and neutrino masses. However, in such theories the sterile neutrinos turn out to be too sterile: their feeble interactions with the Standard Model generically result in an under-abundance of dark matter and baryons, and the theory is only consistent with cosmological observations with substantial tuning of model parameters. I show how new interactions coupled to Standard Model leptons greatly enhance the baryon and dark matter abundances, eliminating the need for tuning among parameters, and giving generic predictions for probing models of not-so-sterile neutrinos at the LHC and intensity frontier experiments.