SUSY dark matter annihilation in the Galactic halo

Abstract

Neutralino annihilation in the Galactic halo is the most definite observational signature proposed for indirect registration of the SUSY Dark Matter (DM) candidate particles. The corresponding annihilation signal (in the form of gamma-rays, positrons and antiprotons) may be boosted for one or three orders of magnitude due to the clustering of cold DM particles into the small-scale and very dense self-gravitating clumps. We discuss the formation of these clumps from the initial density perturbations and their successive fate in the Galactic halo. Only a small fraction of these clumps, $\sim 0.1$%, in each logarithmic mass interval $\Delta \log M\sim 1$ survives the stage of hierarchical clustering. We calculate the probability of surviving the remnants of dark matter clumps in the Galaxy by modelling the tidal destruction of the small-scale clumps by the Galactic disk and stars. It is demonstrated that a substantial fraction of clump remnants may survive through the tidal destruction during the lifetime of the Galaxy. The resulting mass spectrum of survived clumps is extended down to the mass of the core of the cosmologically produced clumps with a minimal mass. The survived dense remnants of tidally destructed clumps provide an amplification (boosting) of the annihilation signal with respect to the diffuse DM in the Galactic halo. We describe the anisotropy of clump distribution caused by the tidal destruction of clumps in the Galactic disk.

arXiv comment11 pages, prepared for Proceedings of the 1st International Kaidalov Workshop on the Phenomenology of High Energy Particle Physics

References in corpus (39)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Formation and evolution of galaxy dark matter halos and their substructure
• Earth-mass dark-matter haloes as the first structures in the early Universe
• The first WIMPy halos
• Damping scales of neutralino cold dark matter
• The Small-Scale Power Spectrum of Cold Dark Matter
• The Dynamics of Sinking Satellites Around Disk Galaxies: A Poor Man's Alternative to High-Resolution Numerical Simulations
• Effects of cold dark matter decoupling and pair annihilation on cosmological perturbations
• Small-scale clumps in the galactic halo and dark matter annihilation
• Updated Post-WMAP Benchmarks for Supersymmetry
• Dark Matter from Early Decays
• Two measures of the shape of the Milky Way's dark halo
• Anisotropy of the cosmic gamma-ray background from dark matter annihilation
• Early supersymmetric cold dark matter substructure
• Amplification of Cosmological Inhomogeneities by the QCD Transition
• The surface brightness of dark matter: unique signatures of neutralino annihilation in the Galactic halo
• Dark Matter Annihilation in Substructures Revised
• On the Self-Consistent Response of Stellar Systems to Gravitational Shocks
• The survival and disruption of CDM micro-haloes: implications for direct and indirect detection experiments
• Luminous and Dark Matter in the Milky Way
• Galactic Substructure and Direct Detection of Dark Matter
• Adiabatic Invariants in Stellar Dynamics: II. Gravitational shocking
• Destruction of small-scale dark matter clumps in the hierarchical structures and galaxies
• EGRET Excess of Diffuse Galactic Gamma Rays as Tracer of Dark Matter
• Remnants of dark matter clumps
• Dark Matter Halos with Cores from Hierarchical Structure Formation
• Analytical Approach to Subhaloes Population in Dark Matter Haloes
• Formation and internal structure of superdense dark matter clumps and ultracompact minihaloes
• On mini-halo encounters with stars
• Superdense cosmological dark matter clumps
• Constraints on diffuse neutrino background from primordial black holes
• Analysis of galactic tides and stars on CDM microhalos
• Angular Signatures of Dark Matter in the Diffuse Gamma Ray Background
• Anisotropy of dark matter annihilation with respect to the Galactic plane
• Annihilations of superheavy dark matter in superdense clumps
• Dense DM clumps seeded by cosmic string loops and DM annihilation
• Neutralino Annihilations and the Gas Temperature in the Dark Ages
• Earth-mass dark halos are torn into dark mini-streams by stars
• Small-scale structure of cold dark matter

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