Impact of Dark Photon Emission on Massive Star Evolution and Pre-Supernova Neutrino Signal

TL;DR

This paper investigates how dark photon emission affects the late-stage evolution of a 15 solar mass star and its pre-supernova neutrino signals, revealing potential observational signatures of dark matter particles.

Contribution

It provides the first detailed analysis of dark photon effects on massive star evolution and pre-supernova neutrino emissions, including semi-analytical estimates and numerical simulations.

Findings

Dark photon emission accelerates silicon burning, reducing neutrino emission before collapse.

Certain dark photon parameters can increase neutrino emission due to shell burning episodes.

Strong couplings may cause thermonuclear runaway, potentially disrupting the star.

Abstract

We study the effects of additional cooling due to the emission of a dark matter candidate particle, the dark photon, on the final phases of the evolution of a $15\,M_\odot$ star and resulting modifications of the pre-supernova neutrino signal. For a substantial portion of the dark photon parameter space the extra cooling speeds up Si burning, which results in a reduced number of neutrinos emitted during the last day before core collapse. This reduction can be described by a systematic acceleration of the relevant timescales and the results can be estimated semi-analytically in good agreement with the numerical simulations. Outside the semi-analytic regime we find more complicated effects. In a narrow parameter range, low-mass dark photons lead to an increase of the number of emitted neutrinos because of additional shell burning episodes that delay core collapse. Furthermore, relatively strong couplings produce a thermonuclear runaway during O burning, which could result in a complete disruption of the star but requires more detailed simulations to determine the outcome. Our results show that pre-supernova neutrino signals are a potential probe of the dark photon parameter space.