Diffuse Supernova Neutrino Background from extensive core-collapse simulations of $8$-$100 {\rm M}_\odot$ progenitors

TL;DR

This paper models the diffuse supernova neutrino background considering detailed core-collapse simulations across a wide mass range, highlighting how progenitor properties influence neutrino emissions and potential black hole formation.

Contribution

It introduces a comprehensive set of neutrino emission models from 8 to 100 solar masses, incorporating both neutron star and black hole formation scenarios based on core compactness.

Findings

Neutrino emission varies non-monotonically with progenitor mass.

Future neutrino background detections could reveal the black hole formation threshold.

High core compactness favors black hole formation.

Abstract

We revisit the diffuse supernova neutrino background in light of recent systematic studies of stellar core collapse that reveal the quantitative impacts of the progenitor conditions on the collapse process. In general, the dependence of the progenitor on the core-collapse neutrino emission is not monotonic in progenitor initial mass, but we show that it can, at first order, be characterized by the core compactness. For the first time, we incorporate the detailed variations in the neutrino emission over the entire mass range $8$-$100 {\rm M}_\odot$, based on (i) a long-term simulation of the core collapse of a $8.8 {\rm M}_\odot$ O-Ne-Mg core progenitor, (ii) over 100 simulations of iron core collapse to neutron stars, and (iii) half a dozen simulations of core collapse to black holes (the "failed channel"). The fraction of massive stars that undergo the failed channel remains uncertain, but in view of recent simulations which reveal high compactness to be conducive to collapse to black holes, we characterize the failed fraction by considering a threshold compactness above which massive stars collapse to black holes and below which the final remnant is a neutron star. We predict that future detections of the diffuse supernova neutrino background may have the power to reveal this threshold compactness, if its value is relatively small as suggested by interpretations of several recent astronomical observations.