Gamma-ray Constraints on Dark Matter Annihilation into Charged Particles

Abstract

Dark matter annihilation into charged particles is necessarily accompanied by gamma rays, produced via radiative corrections. Internal bremsstrahlung from the final state particles can produce hard gamma rays up to the dark matter mass, with an approximately model-independent spectrum. Focusing on annihilation into electrons, we compute robust upper bounds on the dark matter self annihilation cross section $<{\sigma }_{A}v{>}_{e^{+}{e}^{-}}$ using gamma ray data from the Milky Way spanning a wide range of energies, $\sim 10^{-3}-10^4$ GeV. We also compute corresponding bounds for the other charged leptons. We make conservative assumptions about the astrophysical inputs, and demonstrate how our derived bounds would be strengthened if stronger assumptions about these inputs are adopted. The fraction of hard gamma rays near the endpoint accompanying annihilation to $e^{+}{e}^{-}$ is only a factor of $\alt 10^2$ lower than for annihilation directly to monoenergetic gamma rays. The bound on $<{\sigma }_{A}v{>}_{e^{+}{e}^{-}}$ is thus weaker than that for $<{\sigma }_{A}v{>}_{\gamma \gamma }$ by this same factor. The upper bounds on the annihilation cross sections to charged leptons are compared with an upper bound on the {\it total} annihilation cross section defined by neutrinos.

7 pages, 4 figures; version accepted for publication in Phys. Rev. D

References in corpus (28)

• A Theory of Dark Matter
• The WIMPless Miracle: Dark Matter Particles without Weak-scale Masses or Weak Interactions
• LHC Signals for a SuperUnified Theory of Dark Matter
• New Positron Spectral Features from Supersymmetric Dark Matter - a Way to Explain the PAMELA Data?
• New Gamma-Ray Contributions to Supersymmetric Dark Matter Annihilation
• Heavy Dark Matter Through the Higgs Portal
• Evidence Of Dark Matter Annihilations In The WMAP Haze
• Neutrino Constraints on the Dark Matter Total Annihilation Cross Section
• Pre-launch estimates for GLAST sensitivity to Dark Matter annihilation signals
• The Most Dark Matter Dominated Galaxies: Predicted Gamma-ray Signals from the Faintest Milky Way Dwarfs
• Upper Bound on the Dark Matter Total Annihilation Cross Section
• Fitting the Gamma-Ray Spectrum from Dark Matter with DMFIT: GLAST and the Galactic Center Region
• Gamma-ray continuum emission from the inner Galactic region as observed with INTEGRAL/SPI
• Model-Independent Bound on the Dark Matter Lifetime
• Conservative Constraints on Dark Matter Annihilation into Gamma Rays
• Model-independent dark matter annihilation bound from the diffuse gamma ray flux
• Testing MeV dark matter with neutrino detectors
• Electroweak Bremsstrahlung in Dark Matter Annihilation
• Early Annihilation and Diffuse Backgrounds in 1/v WIMP models
• Searching for Dark Matter with X-ray Observations of Local Dwarf Galaxies
• Radio constraints on dark matter annihilation in the galactic halo and its substructures
• Constraining Supersymmetric Dark Matter With Synchrotron Measurements
• Dark Matter Signatures in the Anisotropic Radio Sky
• Angular Signatures of Dark Matter in the Diffuse Gamma Ray Background
• Dark matter annihilation from intermediate-mass black holes: Contribution to the extragalactic gamma-ray background
• Toward a Minimum Branching Fraction for Dark Matter Annihilation into Electromagnetic Final States
• Cosmic constraints rule out s-wave annihilation of light dark matter
• Constraints on the Dark Matter Annihilations by Neutrinos with Substructure Effects Included

Cited by in corpus (36)

• CMB constraints on Dark Matter models with large annihilation cross-section
• Decaying Dark Matter can explain the electron/positron excesses
• Gamma-ray and radio tests of the e+e- excess from DM annihilations
• Gamma-ray Constraints on Decaying Dark Matter and Implications for IceCube
• The Case for a 700+ GeV WIMP: Cosmic Ray Spectra from PAMELA, Fermi and ATIC
• Primordial Black Holes as Dark Matter: Almost All or Almost Nothing
• WMAP7 and future CMB constraints on annihilating dark matter: implications for GeV-scale WIMPs
• Constraining Very Heavy Dark Matter Using Diffuse Backgrounds of Neutrinos and Cascaded Gamma Rays
• Bounds on Cross-sections and Lifetimes for Dark Matter Annihilation and Decay into Charged Leptons from Gamma-ray Observations of Dwarf Galaxies
• Gamma-ray and Radio Constraints of High Positron Rate Dark Matter Models Annihilating into New Light Particles
• Indirect Detection of Dark Matter Using MeV-Range Gamma-Ray Telescopes
• Constraints on leptonically annihilating Dark Matter from reionization and extragalactic gamma background
• Consistent Scenarios for Cosmic-Ray Excesses from Sommerfeld-Enhanced Dark Matter Annihilation
• Dark Matter Sees The Light
• Gamma Rays from Clusters and Groups of Galaxies: Cosmic Rays versus Dark Matter
• Flavored Dark Matter in Direct Detection Experiments and at LHC
• Indirect Dark Matter Detection Limits from the Ultra-Faint Milky Way Satellite Segue 1
• Implications of the Fermi-LAT diffuse gamma-ray measurements on annihilating or decaying Dark Matter
• Radio and gamma-ray constraints on dark matter annihilation in the Galactic center
• Dark Matter Annihilation Signatures from Electroweak Bremsstrahlung
• Conservative Constraints on Dark Matter from the Fermi-LAT Isotropic Diffuse Gamma-Ray Background Spectrum
• Constraints on WIMP and Sommerfeld-Enhanced Dark Matter Annihilation from HESS Observations of the Galactic Center
• Prospects for Detecting Neutrino Signals from Annihilating/Decaying Dark Matter to Account for the PAMELA and ATIC results
• Lifetime Constraints for Late Dark Matter Decay
• CMSSM Spectroscopy in light of PAMELA and ATIC
• Leading QCD Corrections for Indirect Dark Matter Searches: a Fresh Look
• Prospects for indirect MeV Dark Matter detection with Gamma Rays in light of Cosmic Microwave Background Constraints
• Probing dark matter models with neutrinos from the Galactic center
• Gamma-ray signatures of annihilation to charged leptons in dark matter substructure
• Sommerfeld-Enhanced Annihilation in Dark Matter Substructure: Consequences for Constraints on Cosmic-Ray Excesses
• Multi-messenger constraints on dark matter annihilation into electron-positron pairs
• Neutrino Masses, Leptogenesis and Decaying Dark Matter
• Hidden MeV-Scale Dark Matter in Neutrino Detectors
• Dark matter annihilation and non-thermal Sunyaev-Zel'dovich effect: I. galaxy cluster
• A New Approach to Searching for Dark Matter Signals in Fermi-LAT Gamma Rays
• An Interpretation of the Cosmic Ray $e^{+}+e^{-}$ Spectrum from 10 GeV to 3 TeV Measured by CALET on the ISS