Local dark matter clumps and the cosmic ray positron excess

Abstract

It has been proposed that the excess in cosmic ray positrons at approximately 8 GeV, observed on both flights of the HEAT balloon experiment, may be associated with the annihilation of dark matter within the Milky Way halo. In this paper we demonstrate how the self-annihilation of neutralino dark matter within local substructure can account for this excess, and estimate the annihilation cross-section for several benchmark minimal supersymmetric (MSSM) models. We also demonstrate the effect on the permitted parameter space as tidal stripping effects and destruction of substructure by mergers becomes increasingly severe.

arXiv commentFull-effects of diffusion of the positrons in the ISM have now been incorporated. (Submitted to MNRAS)

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Cited by in corpus (15)

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• The PAMELA and ATIC Excesses From a Nearby Clump of Neutralino Dark Matter
• Searches for Cosmic-Ray Electron Anisotropies with the Fermi Large Area Telescope
• Small-scale clumps of dark matter
• Cosmic ray lepton puzzle in the light of cosmological N-body simulations
• Dark Matter Indirect Signatures
• On prospects for dark matter indirect detection in the Constrained MSSM
• Analysis of galactic tides and stars on CDM microhalos
• Astrophysical Uncertainties in the Cosmic Ray Electron and Positron Spectrum From Annihilating Dark Matter
• Cosmic ray electron anisotropies as a tool to discriminate between exotic and astrophysical sources
• The Galactic positron flux and dark matter substructures
• Constraints on the Dark Matter Annihilations by Neutrinos with Substructure Effects Included
• Numerical Simulations of the Dark Universe: State of the Art and the Next Decade
• Antimatter and Gamma-rays from Dark Matter Annihilation
• Explaining AMS-02 positron excess and muon anomalous magnetic moment in dark left-right gauge model