2021/03/26 by Marina Cermeño, Céline Degrande, Cermeño, Marina +3
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #High Energy Physics - Phenomenology (hep-ph) #Particle Detector Development and Performance
paper · pdf · doi:10.48550/arxiv.2103.14658
openalex publication_date 2021/03/26 · openalex created_date 2025/10/24 · openalex updated_date 2026/07/28
Conventional indirect dark matter (DM) searches look for an excess in the\nelectromagnetic emission from the sky that cannot be attributed to known\nastrophysical sources. Here, we argue that the photon polarisation is an\nimportant feature to understand new physics interactions and can be exploited\nto improve our sensitivity to DM. In particular, circular polarisation can be\ngenerated from Beyond the Standard Model interactions if they violate parity\nand there is an asymmetry in the number of particles which participate in the\ninteraction. In this work, we consider a simplified model for fermionic\n(Majorana) DM and study the circularly polarised gamma rays below 10 GeV from\nthe scattering of cosmic ray electrons on DM. We calculate the differential\nflux of positive and negative polarised photons from the Galactic Center and\nshow that the degree of circular polarization can reach up to 90%. Finally,\nonce collider and DM constraints have been taken into account, we estimate the\nrequired sensitivity from future experiments to detect this signal finding\nthat, although a distinctive peak will be present in the photon flux spectrum,\na near future observation is unlikely. However, different sources or models not\nconsidered in this work could provide higher intensity fluxes, leading to a\npossible detection by e-ASTROGAM. In the event of a discovery, we argue that\nthe polarisation fraction is a valuable characterisation feature of the new\nsector.\n