2025/06/09 by Ye Xu, Xu, Ye
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2506.07395
openalex publication_date 2025/06/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is assumed that superheavy dark matter particles (SHDM, ϕ) with O(ZeV) mass may decay to relativistic milli-charged particles (MCPs, χ) via a channel ϕ→χχ. The downward-going MCPs passing through the atmosphere can be searched for at the Pierre Auger observatory (Auger). The massless hidden photon model is taken for MCPs to interact with nuclei, so that we evaluated the numbers and fluxes of expected MCPs at Auger assuming 14 years of Auger data. The hybrid data of Auger was fitted with the flux of UHE MCPs exceeding GZK-cutoff energy. Then the corresponding upper limits on ε2 are calculated at 90% C. L.. These results indicate that MCPs can be searched for with ε2\gtrsim 3.73×10-5 at Auger, when mϕ=2×1021 eV and τϕ=1027 s. And a new region of 1010 eV < mMCP < 1011.6 eV and ε > 2.02×10-2 is ruled out in the mMCP-ε plane with 14 years of Auger data. These results indicate potential existence of MCPs and SHDM in the Universe.