Can Dark Matter Annihilation Dominate the Extragalactic Gamma-Ray Background?

Abstract

Annihilating dark matter (DM) has been discussed as a possible source of gamma-rays from the galactic center (GC) and contributing to the extragalactic gamma-ray background (EGB). Assuming universality of the density profile of DM halos, we show that it is quite unlikely that DM annihilation is a main constituent of EGB, without exceeding the observed gamma-ray flux from the GC. This argument becomes stronger when we include enhancement of the density profiles by supermassive black holes or baryon cooling. The presence of substructure may loosen the constraint, but only if a very large cross section as well as the rather flat profile are realized.

4 pages, 2 figures, accepted by PRL

Cited by in corpus (24)

• Gamma Ray Signals from Dark Matter: Concepts, Status and Prospects
• Dark Matter Candidates: A Ten-Point Test
• Neutrino Constraints on the Dark Matter Total Annihilation Cross Section
• Upper Bound on the Dark Matter Total Annihilation Cross Section
• Constraining Very Heavy Dark Matter Using Diffuse Backgrounds of Neutrinos and Cascaded Gamma Rays
• High Energy Cosmic Rays from the Decay of Gravitino Dark Matter
• Dark matter annihilation or unresolved astrophysical sources? Anisotropy probe of the origin of cosmic gamma-ray background
• Gamma-Rays from Decaying Dark Matter
• Testing MeV dark matter with neutrino detectors
• The Gamma-Ray-Flux Probability Distribution Function from Galactic Halo Substructure
• TASI 2008 Lectures on Dark Matter
• Muon Fluxes From Dark Matter Annihilation
• Dark stars: Implications and constraints from cosmic reionization and extragalactic background radiation
• Angular Signatures of Dark Matter in the Diffuse Gamma Ray Background
• Dark matter annihilation from intermediate-mass black holes: Contribution to the extragalactic gamma-ray background
• Black Holes as Dark Matter Annihilation Boosters
• Gamma-Rays from Dark Matter Mini-Spikes in M31
• Dark Matter: the Connection with Gamma-Ray Astrophysics
• Cosmic constraints rule out s-wave annihilation of light dark matter
• Astrophysics in 2005
• On the Tremaine-Gunn Limit with Mass-Varying Particles
• Theory and Phenomenology of Dirac Leptogenesis
• Cosmic Neutrino Bound on the Dark Matter Annihilation Rate in the Late Universe
• Prompt cusps in hierarchical dark matter halos: Implications for annihilation boost