Year: 2007
Type: article
Abstract: Weakly interacting massive particles with electroweak scale masses (neutralinos, etc.) remain in kinetic equilibrium with other particle species until temperatures approximately in the range of 10 MeV to 1 GeV, leading to the formation of dark matter substructure with masses as small as ${10}^{\ensuremath{-}4}{M}_{\ensuremath{\bigodot}}$ to ${10}^{\ensuremath{-}12}{M}_{\ensuremath{\bigodot}}$. However, if dark matter consists of particles with MeV scale masses, as motivated by the observation of 511 keV emission from the galactic bulge, such particles are naturally expected to remain in kinetic equilibrium with the cosmic neutrino background until considerably later times. This would lead to a strong suppression of small scale structure with masses below about ${10}^{7}{M}_{\ensuremath{\bigodot}}$ to ${10}^{4}{M}_{\ensuremath{\bigodot}}$. This cutoff scale has important implications for present and future searches for faint local group satellite galaxies and for the missing satellites problem. We also summarize current constraints on the MeV dark matter scenario.
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: HIGH ENERGY PHYSICS RESEARCH: EXPERIMENTAL, THEORETICAL, PHENOMENOLOGY, MATHEMATICAL, ASTROPHYSICAL TESTS OF FUNDAMENTAL PHYSICS (ATP 2000), G222768804, G3611376298, A New Look at Dark Matter in the Universe, HIGH ENERGY PHYSICS RESEARCH EXPERIMENTAL, THEORETICAL, PHENOMENOLOGY, MATHEMATICAL, COLLABORATIVE RESEARCH: Structure Formation on Small Scales and the Nature of Cold Dark Matter
OpenAlex ID: W2030226271