EGRET Excess of Diffuse Galactic Gamma Rays as Tracer of Dark Matter

Abstract

The public data from the EGRET space telescope on diffuse Galactic gamma rays in the energy range from 0.1 to 10 GeV are reanalyzed with the purpose of searching for signals of Dark Matter annihilation (DMA). The analysis confirms the previously observed excess for energies above 1 GeV in comparison with the expectations from conventional Galactic models. In addition, the excess was found to show all the key features of a signal from Dark Matter Annihilation (DMA): a) the excess is observable in all sky directions and has the same shape everywhere, thus pointing to a common source; b) the shape corresponds to the expected spectrum of the annihilation of non-relativistic massive particles into - among others - neutral ${\pi }^0$ mesons, which decay into photons. From the energy spectrum of the excess we deduce a WIMP mass between 50 and 100 GeV, while from the intensity of the excess in all sky directions the shape of the halo could be reconstructed. The DM halo is consistent with an almost spherical isothermal profile with substructure in the Galactic plane in the form of toroidal rings at 4 and 14 kpc from the center. These rings lead to a peculiar shape of the rotation curve, in agreement with the data, which proves that the EGRET excess traces the Dark Matter.

29 pages, 15 figures, accepted by A&A

References in corpus (34)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• A Universal Density Profile from Hierarchical Clustering
• Supersymmetric Dark Matter
• High-Energy-Physics Event Generation with PYTHIA 6.1
• Propagation of cosmic-ray nucleons in the Galaxy
• Non-Baryonic Dark Matter - Observational Evidence and Detection Methods
• The Ghost of Sagittarius and Lumps in the Halo of the Milky Way
• EGRET Observations of the Extragalactic Gamma Ray Emission
• Diffuse continuum gamma rays from the Galaxy
• Observability of Gamma Rays from Dark Matter Neutralino Annihilations in the Milky Way Halo
• Diffuse Galactic continuum gamma rays. A model compatible with EGRET data and cosmic-ray measurements
• Earth-mass dark-matter haloes as the first structures in the early Universe
• A Low Latitude Halo Stream around the Milky Way
• The Structural Evolution of Substructure
• The Present and Future Mass of the Milky Way Halo
• A Geometric Determination of the Distance to the Galactic Center
• Cosmological dark matter annihilations into gamma-rays - a closer look
• One Ring to Encompass them All: A giant stellar structure that surrounds the Galaxy
• Spectral Gamma-ray Signatures of Cosmological Dark Matter Annihilation
• Internal Alignment of the Halos of Disk Galaxies in Cosmological Hydrodynamic Simulations
• Exploring Halo Substructure with Giant Stars: Spectroscopy of Stars in the Galactic Anticenter Stellar Structure
• The Galactic Center as a Dark Matter Gamma-Ray Source
• High Energy Gamma--Radiation from the Galactic Center due to Neutralino Annihilation
• Dark halo properties from rotation curves
• Luminous and Dark Matter in the Milky Way
• Bar-Induced Evolution of Dark Matter Cusps
• Annihilation Radiation from a Dark Matter Spike at the Galactic Centre
• On the nature of the ring-like structure in the outer Galactic disk
• Neutralino Annihilation at the Galactic Center Revisited
• Particle Dark Matter Constraints from the Draco Dwarf Galaxy
• Diffractive Interaction and Scaling Violation in pp->pi^0 Interaction and GeV Excess in Galactic Diffuse Gamma-Ray Spectrum of EGRET
• Gamma Rays from Neutralino Annihilation
• The Highest-Energy Photons Seen by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory
• Evidence for Dark Matter Annihilation from Galactic Gamma Rays?

Cited by in corpus (62)

• Cosmic-ray propagation and interactions in the Galaxy
• Global properties of the HI distribution in the outer Milky Way
• Gamma Ray Signals from Dark Matter: Concepts, Status and Prospects
• Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy
• Dark Matter Candidates: A Ten-Point Test
• Baryonic Pinching of Galactic Dark Matter Halos
• Dark matter in the Milky Way, II. the HI gas distribution as a tracer of the gravitational potential
• Dark Matter Evidence, Particle Physics Candidates and Detection Methods
• Fermi Large Area Telescope Measurements of the Diffuse Gamma-Ray Emission at Intermediate Galactic Latitudes
• A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro
• Cosmic Ray Protons in the Inner Galaxy and the Galactic Center Gamma-Ray Excess
• Constraints on Scalar Dark Matter from Direct Experimental Searches
• Dark Matter Searches with Astroparticle Data
• The Blazar Sequence and the Cosmic Gamma-Ray Background Radiation in the Fermi Era
• Kinematical and chemical vertical structure of the Galactic thick disk II. A lack of dark matter in the solar neighborhood
• Relic density and CMB constraints on dark matter annihilation with Sommerfeld enhancement
• Remnants of dark matter clumps
• Cold Dark Matter as Compact Composite Objects
• Gamma ray astrophysics: the EGRET results
• Small-scale clumps of dark matter
• The Likely Cause of the EGRET GeV Anomaly and its Implications
• Angular Signatures of Annihilating Dark Matter in the Cosmic Gamma-Ray Background
• Microlensing towards the SMC: a new analysis of OGLE and EROS results
• Source population synthesis and the Galactic diffuse gamma-ray emission
• Physical laboratory at the center of the Galaxy
• SUSY-QCD Corrections to Dark Matter Annihilation in the Higgs Funnel
• Fermi Gamma-ray Space Telescope: High-Energy Results from the First Year
• Secondary radiation from the Pamela/ATIC excess and relevance for Fermi
• Low Mass Dark Matter and Invisible Higgs Width In Darkon Models
• Is the dark matter interpretation of the EGRET gamma excess compatible with antiproton measurements?
• Search for Dark Matter
• Dark stars: Implications and constraints from cosmic reionization and extragalactic background radiation
• The supersymmetric interpretation of the EGRET excess of diffuse Galactic gamma rays
• Supersymmetry on the Run: LHC and Dark Matter
• Probing Dark Matter Dynamics via Earthborn Neutrinos at IceCube
• The Spectral Shape of the Gamma-ray Background from Blazars
• Comprehensive Constraints on a Spin-3/2 Singlet Particle as a Dark Matter Candidate
• Constraints on the TeV source population and its contribution to the galactic diffuse TeV emission
• Supersymmetry and LHC
• Non-thermal X-rays from the Ophiuchus galaxy cluster and dark matter annihilation
• Gravitational potential of a homogeneous circular torus: new approach
• Antiproton signatures from astrophysical and dark matter sources at the galactic center
• Galactic diffuse gamma rays --- recalculation based on the new measurements of cosmic electron spectrum
• Beyond the Standard Model
• Understanding limitations in the determination of the diffuse Galactic gamma-ray emission
• Spheroidal and torsional modes of quasistatic shear oscillations in the solid globe models of nuclear physics and pulsar astrophysics
• Astrophysics in 2006
• The diffuse GeV-TeV $\gamma$-ray emission of the Cygnus region
• Cosmic constraints rule out s-wave annihilation of light dark matter
• Condensation of Galactic Cold Dark Matter
• The diffuse Galactic gamma-rays from dark matter annihilation
• Diffuse $\gamma$-rays and $\bar{p}$ flux from dark matter annihilation -- a model for consistent results with EGRET and cosmic ray data
• A new Determination of the Extragalactic Background of Diffuse Gamma Rays taking into account Dark Matter Annihilation
• Light Superpartners at Hadron Colliders
• Dark matter annihilation at cosmological redshifts: possible relic signal from annihilation of weakly interacting massive particles
• SUSY interpretation of the Egret GeV anomaly, Xenon-10 dark matter search limits and the LHC
• The Futile Search for Galactic Disk Dark Matter
• Fundamental physics in space with the Fermi Gamma-ray Space Telescope
• SUSY dark matter annihilation in the Galactic halo
• Helium reionization in the presence of self-annihilating clumpy dark matter
• Perspective of Galactic dark matter subhalo detection on Fermi from the EGRET observation
• Impact of Sommerfeld enhancement on helium reionization via WIMP dark matter