Uncovering axionlike particles in supernova gamma-ray spectra
Francesca Calore, Pierluca Carenza, Christopher Eckner, Maurizio Giannotti, Giuseppe Lucente, Alessandro Mirizzi, Francesco Sivo
Abstract
A future Galactic supernova (SN) explosion can lead to a gamma-ray signal induced by ultralight axionlike particles (ALPs) thermally produced in the SN core and converted into high-energy photons in the Galactic magnetic field. The detection of such a signal is in the reach of the Large Area Telescope aboard the Fermi Gamma-Ray Space Telescope. The observation of gamma-ray emission from a future SN has a sensitivity to ${g}_{a\ensuremath{\gamma}}\ensuremath{\gtrsim}4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}\text{ }\text{ }{\mathrm{GeV}}^{\ensuremath{-}1}$ for a SN at fiducial distance of 10 kpc and would allow us to reconstruct the ALP-photon coupling within a factor of $\ensuremath{\sim}2$, mainly due to the uncertainties on the modeling of the Galactic magnetic field.