Speaker
Description
Core-collapse supernovae can be a copious source of sterile neutrinos, hypothetical particles that mix with active neutrinos. We develop two-dimensional stellar core-collapse models that incorporate the mixing between tau neutrinos and heavy sterile neutrinos---those with the mass of 150--200 MeV---to investigate signatures of sterile neutrinos in supernova observables. We find that the decay channel of a sterile neutrino into a pion and a tau neutrino can enhance the explosion energy and the synthesized nickel mass. Although the inclusion of sterile neutrinos considered in this study slightly reduce the neutrino and gravitational-wave signals, we find that they are still detectable for a Galactic event. Furthermore, we point out that if sterile neutrinos are as massive as $\sim200$ MeV, they produce high-energy tau antineutrinos with energies of $\sim80$ MeV, the detection of which can be a smoking signature of the sterile neutrinos and where Hyper-Kamiokande should play a pivotal role.
