Damping of supernova neutrino transitions in stochastic shock-wave density profiles

Abstract

Supernova neutrino flavour transitions during shock-wave propagation are known to encoderelevant information not only about the matter density profile but also about unknownneutrino properties, such as the mass hierarchy (normal or inverted) and the mixing angleθ13. While previous studies have focused on ‘deterministic’ density profiles, we investigate theeffect of possible stochastic matter density fluctuations in the wake of supernovashock-waves. In particular, we study the impact of small-scale fluctuations on the electron(anti)neutrino survival probability, and on the observable spectra of inverse beta-decayevents in future water–Cherenkov detectors. We find that such fluctuations, evenwith relatively small amplitudes, can have significant damping effects on theflavour transition pattern, and can partly erase the shock-wave imprint on theobservable time spectra, especially for .