2016/09/30 by A. D. Dolgov, A. S. Rudenko · 4 citations
Physics and Astronomy · #Abundance (ecology) #Astrophysics #Charge (physics) #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Ecology #Electric charge #Electron #Fermion #Nuclear physics #Particle physics #Physics #Quantum mechanics #Scalar (mathematics) #Solar and Space Plasma Dynamics #hep-ph
paper · pdf · doi:10.1134/s1063776117030116
published in Journal of Experimental and Theoretical Physics 124(4), 564-569 (Pleiades Publishing) · 7 pages, 3 figures; references added; final version published in JETP
openalex publication_date 2017/04/01 · arxiv created 2017/05/16 · arxiv updated 2017/05/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The relic abundance of light millicharged particles (MCPs) with the electric charge e′ = 5 × 10–5 e and with the mass slightly below or above the electron mass is calculated. The abundance depends on the mass ratio η = m X /m e and for η < 1 can be high enough to allow MCPs to be the cosmological dark matter or to make a noticeable contribution to it. On the other hand, for η ≳ 1 the cosmological energy density of MCPs can be quite low, Ω X h 0 2 ≈ 0.02 for scalar MCPs, and Ω X h 0 2 ≈ 0.001 for spin 1/2 fermions. But even the lowest value of Ω X h 0 2 is in tension with several existing limits on the MCP abundances and parameters. However, these limits have been derived under some natural or reasonable assumptions on the properties of MCPs. If these assumptions are relaxed, a patch in the mass–charge plot of MCPs may appear, permitting them to be dark matter particles.