The excess of diffuse radio emission in galaxy clusters A4038 and A1664

Abstract

In this study, we investigate the potential connection between Dark matter (DM) particles and synchrotron emission in galaxy clusters, with a focus on radio relics. We explore three models beyond the standard model of particle physics and calculate emissions from DM particle candidates, comparing the results to radio observations. Our analysis centres on galaxy clusters A4038 and A1664, considering their radio properties and magnetic field characteristics. We employ the Navarro, Frenk, and White (NFW) profile to represent mass density distributions and in situ acceleration models for cosmic ray contributions. We estimate upper limits on DM cross-section annihilation 〈σv〉 for various DM particle candidates for two decay channels (bb̄ and μ+μ− decay channels). Our findings suggest that the DM is not likely the source of the excess emission, but we acknowledge the potential impact of DM on total radio emissions in galaxy clusters. Further studies are needed to refine excess emissions and assess DM’s influence on the total radio emissions. In summary, this research delves into the intricate relationship between DM particles and radio emissions in galaxy clusters, emphasizing the need for precise modelling and observation to unveil the mysteries of DM.