2019/02/28 by Jia Liu, Xiao-Ping Wang, Wei Xue · 5 citations
Physics and Astronomy · #Astrophysics #Atomic physics #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Dark fluid #Dark matter #Dark photon #Fermion #Galaxies: Formation, Evolution, Phenomena #Hot dark matter #Light dark matter #Particle physics #Photon #Physics #Quantum mechanics #Scalar field dark matter #Thermalisation #Warm dark matter #astro-ph.HE #hep-ph
paper · pdf · doi:10.1103/physrevd.100.123012
published in Physical review. D/Physical review. D. 100(12) (American Physical Society) · 8 pages; version published in PRD
arxiv created 2019/12/16 · openalex publication_date 2019/12/17 · arxiv updated 2019/12/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We propose a novel mechanism with two component dark matter models. The subdominant dark matter can thermalize the dominant one in galaxies, and leads to core density profiles. Using ultralight dark photons and GeV-TeV Dirac fermions as an example, we couple the two dark matter candidates with a U(1) interaction. This mechanism differs from self-interacting dark matter, due to three effects: (1) higher occupation numbers, (2) forward-backward scattering cancellation, and (3) the multiple scatterings required for the heavy dark matter. Furthermore, the Bullet Cluster bound is evaded due to the reduced Bose enhancement factor. Unlike the fuzzy dark matter solution to the small structure problems which have tension with Lyman-\ensuremathα, the ultralight dark photons with mass \ensuremath\gtrsim10^\ensuremath-21 eV can have a core profile through interactions with \ensuremathψ and are not constrained by other astrophysical observations.