Effects of Inelastic Neutrino-Nucleus Scattering on Supernova Dynamics and Radiated Neutrino Spectra

TL;DR

This study calculates inelastic neutrino-nucleus scattering rates in supernovae, showing increased neutrino opacity and spectral modifications, which impact neutrino detection but do not significantly alter supernova dynamics.

Contribution

It provides detailed reaction rates for INNS under supernova conditions using advanced nuclear models, integrated into core-collapse simulations.

Findings

INNS increases neutrino opacities in supernova matter.

High-energy neutrino tail is strongly reduced during shock breakout.

Expected neutrino detection rates decrease by up to 60% due to INNS.

Abstract

Based on the shell model for Gamow-Teller and the Random Phase Approximation for forbidden transitions, we have calculated reaction rates for inelastic neutrino-nucleus scattering (INNS) under supernova (SN) conditions, assuming a matter composition given by Nuclear Statistical Equilibrium. The rates have been incorporated into state-of-the-art stellar core-collapse simulations with detailed energy-dependent neutrino transport. While no significant effect on the SN dynamics is observed, INNS increases the neutrino opacities noticeably and strongly reduces the high-energy tail of the neutrino spectrum emitted in the neutrino burst at shock breakout. Relatedly the expected event rates for the observation of such neutrinos by earthbound detectors are reduced by up to about 60%.