Constraints on axion-like particles from X-ray observations of Hydra galaxy cluster

Understand

Axion-like particles (ALPs) belong to a class of new pseudoscalar particles that generically couple to photons, opening the possibility of oscillations from photons into ALPs in an external magnetic field.

• Having witnessed the turbulence of their magnetic fields, these oscillations are expected to imprint irregularities in a limited energy range of the spectrum of astrophysical sources.
• In this study, Chandra observations of the Hydra galaxy cluster are used to constrain the value of the coupling of ALPs to photons.
• We consider the conversion of X-ray photons from the central source Hydra A in the magnetic field of the cluster.