Modeling Axion-Like Particles in Core-collapse SNs

3D template-based $Fermi$-LAT constraints on axion-like particles

Axion-like particles (alps) may be abundantly produced in core-collapse supernovae (sne), hence the cumulative signal from all past events would contain an alp component and create a diffuse flux peaked at energies of about 50 mev.We update the calculation of this flux by including a set of core-collapse (cc)supernovae (sne) models with different progenitor masses following the expected massdistribution.This yields an improvement of roughly a factor of two for the upper limit on the alp-photon coupling constant compared to a previous analysis that accounted only for the spectral shape of the signal.The combined effect is still an improvement of the limit and in particular its statistical reliability.We also show that our results are robust against variations in the modeling of high-latitude galactic diffuse emission and systematic uncertainties of the latitudinal angle distribution (lat).