Heavy axion-like particles and core-collapse supernovae: constraints and impact on the explosion mechanism

Abstract

Heavy axion-like particles (ALPs), with masses $m_a\gtrsim 100$ keV, coupled with photons, would be copiously produced in a supernova (SN) core via Primakoff process and photon coalescence. Using a state-of-the-art SN model, we revisit the energy-loss SN 1987A bounds on axion-photon coupling. Moreover, we point out that heavy ALPs with masses $m_a\gtrsim 100$ MeV and axion-photon coupling $g_{a\gamma }\gtrsim 4\times 10^{-9}$ GeV${}^{-1}$ would decay into photons behind the shock-wave producing a possible enhancement in the energy deposition that would boost the SN shock revival.

Comments: v2 (32 pages, 21 figure): revised version. Matches the published version on JCAP. Major changes to improve the robustness of the bound. Added two Appendices on the possible constraining criteria and on the effect of the SN progenitor mass on the bound