The Fermi-LAT observations of SN 2023ixf, a Type II supernova in the nearby
Pinwheel Galaxy, Messier 101 (M101), presents us with an excellent opportunity
to constrain MeV-scale Axion-Like Particles (ALPs). By examining the photon
decay signature from heavy ALPs that could be produced in the explosion, we
improve the existing constraints on the ALP-photon coupling by up to a factor
of ∼2 for masses ma≲3 MeV, with the exact value depending
mostly on plasma properties of the collapsing core. This study demonstrates the
relevance of core-collapse supernovae, also beyond the Magellanic Clouds, as
probes of fundamental physics.Comment: 7 pages, 2 figure