Analysis of the Very Inner Milky Way Dark Matter Distribution and Gamma-Ray Signals

Abstract

We analyze the possibility that the HESS gamma-ray source at the Galactic Center could be explained as the secondary flux produced by annihilation of TeV Dark Matter (TeVDM) particles with locally enhanced density, in a region spatially compatible with the HESS observations themselves. We study the inner 100 pc considering (i) the extrapolation of several density profiles from state-of-the-art N-body + Hydrodynamics simulations of Milky Way-like galaxies, (ii) the DM spike induced by the black hole, and (iii) the DM particles scattering off by bulge stars. We show that in some cases the DM spike may provide the enhancement in the flux required to explain the cut-off in the HESS J1745-290 gamma-ray spectra as TeVDM. In other cases, it may helps to describe the spatial tail reported by HESS II at angular scales < 0.54 degrees towards Sgr A.

6 pages, 3 figures, 1 table. Accepted for publication in Physical Review D - Rapid Communications

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• Background Modelling in Very-High-Energy gamma-ray Astronomy
• A Tale of Tails: Dark Matter Interpretations of the Fermi GeV Excess in Light of Background Model Systematics
• Baryonic and dark matter distribution in cosmological simulations of spiral galaxies
• Dark matter dynamics in Galactic center
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Cited by in corpus (3)

• Dark matter spikes in the vicinity of Kerr black holes
• Dependence of accessible dark matter annihilation cross-sections on the density profiles of dwarf spheroidal galaxies with the Cherenkov Telescope Array
• On the possible enhancement of the dark matter density distribution at the galactic center