Description
Axions and axion-like particles (ALPs) are some of the best-motivated candidates for dark matter. Their coupling to photons leads to radiative decays of axion dark matter and axion-photon conversion in an external magnetic field. We discuss two methods to search for these signals by exploiting astrophysical data. The first is based on spectroscopic optical observations of a sample of five classical and ultra-faint dwarf spheroidal galaxies. We present new limits on ALPs radiative decays for ALPs masses in the eV range. The second strategy relies on the conversion of axions into photons in the Sun’s magnetic field. Leveraging the production of axions in the solar core, we report strong bounds for axion masses below 1e-4 eV from solar X-ray observations.
