Cooling the Shock: New Supernova Constraints on Dark Photons

TL;DR

This paper investigates how dark photons could influence supernova explosions by providing a new cooling mechanism, leading to novel constraints on dark photon properties based on supernova observations.

Contribution

It introduces a new supernova-based method to constrain dark photon parameters, especially in the 0.1-0.4 MeV mass range, surpassing previous bounds from SN1987A.

Findings

Dark-photon cooling can significantly affect supernova dynamics.

New constraints on dark photon mass and coupling are established.

Supernova observations can probe dark photons down to 0.01 MeV.

Abstract

During the accretion phase of a core-collapse supernova (SN), dark-photon (DP) cooling can be largest in the gain layer below the stalled shock wave. In this way, it could counter-act the usual shock rejuvenation by neutrino energy deposition and thus prevent the explosion. This peculiar energy-loss profile derives from the resonant nature of DP production. The largest cooling and thus strongest constraints obtain for DP masses of 0.1-0.4 MeV, a range corresponding to the photon plasma mass in the gain region. Electron-capture SNe, once observationally unambiguously identified, could provide strong bounds even down to nearly 0.01 MeV. For a coupling strength so small that neutrino-driven explosions are expected to survive, the DP cooling of the core is too small to modify the neutrino signal, i.e., our new argument supersedes the traditional SN1987A cooling bound.