Speaker
Description
Strong self-interaction among the active neutrinos mediated by a neutrinophilic scalar is a well-motivated target of particle physics and cosmological probes. In this talk, I will present precision electroweak constraints on models for neutrino self-interaction, pointing out the importance of neutrino charged-current coupling correction and its impact on the Fermi constant measurements. This effect was overlooked previously and allows us to derive the leading constraint on the neutrinophilic couplings for the mediator mass above a few hundred MeV. Further, I will talk about a UV completion including a TeV-scale $SU(2)_L$ triplet scalar and show that the simplified model constraints continue to hold for a wide range of parameter space. These results serve as a useful road map for future explorations of the self-interacting neutrino paradigm.