Estimating the core compactness of massive stars with Galactic supernova neutrinos

TL;DR

This paper demonstrates that neutrino signals from Galactic supernovae can reveal the inner mass density structure of progenitor stars, with simulations showing a correlation between neutrino emissions and core compactness.

Contribution

It introduces a method to infer progenitor core compactness from neutrino observations, supported by 20 supernova simulations across various initial masses.

Findings

Neutrino emissions during accretion correlate with progenitor compactness.

The ratio of early neutrino events can indicate the progenitor's inner structure.

Flavor mixing introduces uncertainties in the neutrino-based inferences.

Abstract

We suggest the future detection of neutrinos from a Galactic core-collapse supernova can be used to infer the progenitor's inner mass density structure. We present the results from 20 axisymmetric core-collapse supernova simulations performed with progenitors spanning initial masses in the range 11--30Msun, and focus on their connections to the progenitor compactness. The compactness is a measure of the mass density profile of the progenitor core and recent investigations have suggested its salient connections to the outcomes of core collapse. Our simulations confirm a correlation between the neutrinos emitted during the accretion phase and the progenitor's compactness, and that the ratio of observed neutrino events during the first hundreds of milliseconds provides a promising handle on the progenitor's inner structure. Neutrino flavor mixing during the accretion phase remains a large source of uncertainty.