Matt Kistler homepage.  Matthew Kistler  Core Collapse Astrophysics with a Five Megaton Neutrino Detector

The legacy of solar neutrinos suggests that large neutrino detectors should be sited underground.  However, to instead go underwater bypasses the need to move mountains, allowing much larger contained water Cherenkov detectors.  Reaching a scale of ~5 Megatons would permit observations of "mini-bursts" of neutrinos from supernovae in the nearby universe on a yearly basis.  Importantly, these mini-bursts would be detected over backgrounds without the need for corroborating optical evidence of a supernova, guaranteeing the beginning of time-domain MeV neutrino astronomy.  The ability to identify, to the second, every core collapse would allow a continuous "death watch" of all stars within ~5 Mpc, making previously-impossible tasks practical.  These include the abilities to promptly detect otherwise-invisible prompt black hole formation, provide advance warning for supernova shock-breakout searches, define tight time windows for gravitational-wave searches, and identify "supernova impostors" by the non-detection of neutrinos.