New signature of dark matter annihilations: Gamma rays from intermediate-mass black holes

2005/09/19 by Gianfranco Bertone, Andrew R. Zentner, Joseph Silk · 7 citations
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph #hep-ph

paper · pdf · doi:10.1103/physrevd.72.103517

published as Phys.Rev.D72:103517,2005 · 11 pages, 5 figures

arxiv created 2005/09/19 · openalex publication_date 2005/11/16 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31

Abstract

We study the prospects for detecting gamma rays from dark matter (DM) annihilations in enhancements of the DM density (mini-spikes) around intermediate-mass black holes (IMBH) with masses in the range 10²\ensuremath\lesssimM/M_\ensuremath\bigodot\ensuremath\lesssim10⁶. Focusing on two different IMBH formation scenarios, we show that, for typical values of mass and cross section of common DM candidates, mini-spikes, produced by the adiabatic growth of DM around pregalactic IMBHs, would be bright sources of gamma rays, which could be easily detected with large field-of-view gamma-ray experiments such as GLAST, and further studied with smaller field-of-view, larger-area experiments like Air Cherenkov Telescopes CANGAROO, HESS, MAGIC, and VERITAS. The detection of many gamma-ray sources not associated with a luminous component of the Local Group, and with identical cutoffs in their energy spectra at the mass of the DM particle, would provide a potential smoking-gun signature of DM annihilations and shed new light on the nature of intermediate and supermassive black holes.

Citations

• Can Dark Matter Annihilation Dominate the Extragalactic Gamma-Ray Background?
• Neutralino annihilation intoγrays in the Milky Way and in external galaxies
• Intermediate-Mass Black Holes
• The Physics of Galaxy Clustering. I. A Model for Subhalo Populations

Cited by

• Gamma-ray constraints on dark matter annihilation into charged particles
• Revealing dark matter substructure with anisotropies in the diffuse gamma-ray background
• Gamma rays from dark matter minispikes in the Andromeda Galaxy M31
• Black holes in our galactic halo: compatibility with FGST and PAMELA data and constraints on the first stars
• Galactic antiproton spectrum at high energies: Background expectation versus exotic contributions
• Dark matter annihilation or unresolved astrophysical sources? Anisotropy probe of the origin of the cosmic gamma-ray background
• A luminosity constraint on the origin of unidentified high energy sources