Composition of the Fermi-LAT isotropic gamma-ray background intensity: Emission from extragalactic point sources and dark matter annihilations

Abstract

A new estimation of the isotropic diffuse gamma-ray background (IGRB) observed by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) has been presented for 50 months of data, in the energy range 100 MeV-820 GeV and for different modelings of the Galactic foreground. We attempt here the interpretation of the Fermi-LAT IGRB data in terms of the gamma-ray unresolved emission from different extragalactic populations. We find very good fits to the experimental IGRB, obtained with theoretical predictions for the emission from active galactic nuclei and star-forming galaxies. In addition, we probe a possible emission coming from the annihilation of weakly interacting dark matter (DM) particles in the halo of our Galaxy. We set stringent limits on its annihilation cross section into gamma rays, which are about the thermal relic value for a wide range of DM masses. We also identify regions in the DM mass and annihilation cross section parameter space which can significantly improve the fit to the IGRB data. Our analysis is conducted within the different IGRB data sets obtained from different models for the Galactic emission, which is shown to add a significant ambiguity on the IGRB interpretation.

17 pages, 9 figures, 5 tables. This version matches the published version, minor changes only

References in corpus (22)

• The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV
• Concentration, Spin and Shape of Dark Matter Haloes as a Function of the Cosmological Model: WMAP1, WMAP3 and WMAP5 results
• The Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived From First-Year Fermi Large Area Telescope Data
• The Imprint of The Extragalactic Background Light in the Gamma-Ray Spectra of Blazars
• Constraints on the Galactic Halo Dark Matter from Fermi-LAT Diffuse Measurements
• Gamma Ray Signals from Dark Matter: Concepts, Status and Prospects
• The Fermi-LAT high-latitude Survey: Source Count Distributions and the Origin of the Extragalactic Diffuse Background
• Star-forming galaxies as the origin of diffuse high-energy backgrounds: Gamma-ray and neutrino connections, and implications for starburst history
• Constraints on Dark Matter Annihilation in Clusters of Galaxies with the Fermi Large Area Telescope
• Updated CMB constraints on Dark Matter annihilation cross-sections
• Galactic masers and the Milky Way circular velocity
• Inverse Compton constraints on the Dark Matter e+e- excesses
• Indirect Dark Matter Detection from Dwarf Satellites: Joint Expectations from Astrophysics and Supersymmetry
• Search for dark matter annihilation signatures in H.E.S.S. observations of Dwarf Spheroidal Galaxies
• Cosmic Gamma-Ray Background from Star-Forming Galaxies
• Statistics of Cosmological Black Hole Jet Sources: Blazar Predictions for GLAST
• Diffuse gamma-ray emission from galactic pulsars
• Evidence of cross-correlation between the CMB lensing and the gamma-ray sky
• Fermi-LAT gamma-ray anisotropy and intensity explained by unresolved Radio-Loud Active Galactic Nuclei
• BL Lac Contribution to the Extragalactic Gamma-Ray Background
• Constraining Dark Matter in Galactic Substructure
• Diffuse gamma-ray constraints on dark matter revisited. I: the impact of subhalos

Cited by in corpus (76)

• Resolving the Extragalactic $\gamma$-ray Background above 50 GeV with Fermi-LAT
• A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics
• Evidence against star-forming galaxies as the dominant source of IceCube neutrinos
• The nature of the Diffuse Gamma-Ray Background
• Sensitivity Projections for Dark Matter Searches with the Fermi Large Area Telescope
• Probing the origin of ultra-high-energy cosmic rays with neutrinos in the EeV energy range using the Pierre Auger Observatory
• The $\gamma$-ray Emission of Star-Forming Galaxies
• Indirect Detection of Dark Matter Using MeV-Range Gamma-Ray Telescopes
• Constraints on decaying dark matter from the extragalactic gamma-ray background
• Constraints on Stupendously Large Black Holes
• Multimessenger constraints on the dark matter interpretation of the Fermi-LAT Galactic center excess
• Indirect dark matter searches in Gamma- and Cosmic Rays
• Modeling evolution of dark matter substructure and annihilation boost
• Black Holes and WIMPs: All or Nothing or Something Else
• High-energy gamma-ray and neutrino backgrounds from clusters of galaxies and radio constraints
• Robust Constraints and Novel Gamma-Ray Signatures of Dark Matter That Interacts Strongly With Nucleons
• Examining The Fermi-LAT Third Source Catalog In Search Of Dark Matter Subhalos
• Dark matter vs. astrophysics in the interpretation of AMS-02 electron and positron data
• Deciphering Contributions to the Extragalactic Gamma-Ray Background from 2 GeV to 2 TeV
• High-Energy Neutrinos and Gamma-Rays from Non-Relativistic Shock-Powered Transients
• Particle dark matter searches outside the Local Group
• WIMP searches with gamma rays in the Fermi era: challenges, methods and results
• A Case for Radio Galaxies as the Sources of IceCube's Astrophysical Neutrino Flux
• The TeV Diffuse Cosmic Neutrino Spectrum and the Nature of Astrophysical Neutrino Sources
• Unveiling the Gamma-ray Source Count Distribution Below the Fermi Detection Limit with Photon Statistics
• The Gamma-ray Blazar Quest: new optical spectra, state of art and future perspectives
• Mapping Extragalactic Dark Matter Annihilation with Galaxy Surveys: A Systematic Study of Stacked Group Searches
• Active Galactic Nuclei and the Origin of IceCube's Diffuse Neutrino Flux
• Realistic estimation for the detectability of dark matter sub-halos with Fermi-LAT
• Galactic dark matter search via phenomenological astrophysics modeling
• Radio Galaxies Dominate the High-Energy Diffuse Gamma-Ray Background
• Constraints on Dark Matter Annihilation/Decay from the Isotropic Gamma-Ray Background
• Deriving the contribution of blazars to the Fermi-LAT Extragalactic $\gamma$-ray background at $E>10$ GeV with efficiency corrections and photon statistics
• Where do IceCube neutrinos come from? Hints from the diffuse gamma-ray flux
• Gamma Rays From Dark Matter Subhalos Revisited: Refining the Predictions and Constraints
• The origin of the cosmic gamma-ray background in the MeV range
• Testing gamma-ray models of blazars in the extragalactic sky
• Dark Matter Decay to a Photon and a Neutrino: the Double Monochromatic Smoking Gun Scenario
• Gamma-ray luminosity function of BL Lac objects and contribution to the extragalactic gamma-ray background
• Source-count Distribution of Gamma-Ray Blazars
• Constraining Galactic dark matter with gamma-ray pixel counts statistics
• Analyzing the Gamma-ray Sky with Wavelets
• Constraining decaying very heavy dark matter from galaxy clusters with 14 year Fermi-LAT data
• Extreme & High Synchrotron Peak Blazars beyond 4FGL: The 2BIGB $\gamma$-ray catalogue
• TeV Dark Matter Searches in the Extragalactic Gamma-Ray Sky
• Novel Gamma-Ray Signatures of PeV-Scale Dark Matter
• Constraining particle dark matter using local galaxy distribution
• Machine learning methods for constructing probabilistic Fermi-LAT catalogs
• 3FGL J1924.8-1034 : A Spatially-Extended Stable Unidentified GeV Source?
• Measurements and implications of cosmic ray anisotropies from TeV to trans-EeV energies
• New determination of the production cross section for $\gamma$ rays in the Galaxy
• Flat spectrum radio quasars and BL Lacs dominate the anisotropy of the unresolved gamma-ray background
• Gamma Ray Signals from Cosmic Ray Scattering on Axion-Like Particles
• Searching for dark matter annihilation from individual halos: uncertainties, scatter and signal-to-noise ratios
• High-Energy Gamma Rays and Neutrinos from Nearby Radio Galaxies
• Search for heavy dark matter from dwarf spheroidal galaxies: leveraging cascades and subhalo models
• Gamma-ray image reconstruction of the Andromeda galaxy
• Harnessing the Population Statistics of Subhalos to Search for Annihilating Dark Matter
• Constraints on ultracompact minihalos from the extragalactic gamma-ray background observation
• Lower Bound on the Cosmic TeV Gamma-ray Background Radiation
• Multimessenger TeV Dark Matter: a mini review
• Gamma-rays from kilonovae and the cosmic gamma-ray background
• A complete sample of LSP blazars fully described in $\gamma$-rays. New $\gamma$-ray detections and associations with Fermi-LAT
• Addressing $\gamma$-ray emissions from dark matter annihilations in 45 milky way satellite galaxies and in extragalactic sources with particle dark matter models
• Observing small-scale $\gamma$-ray anisotropies with the Cherenkov Telescope Array
• Dark Matter in Leptophilic Higgs Models After the LHC Run-I
• Isotropic diffuse gamma-ray background: unveiling Dark Matter components beyond the contribution of astrophysical sources
• Decaying Fermionic Dark Matter Search with CALET
• Searching for dark matter subhalos in the Fermi-LAT catalog with Bayesian neural networks
• The Dawn of Multi-Messenger Astronomy
• Characterizing the Expected Behavior of Non-Poissonian Template Fitting
• The Galactic Isotropic $\gamma$-ray Background and Implications for Dark Matter
• An Interpretation of the Cosmic Ray $e^{+}+e^{-}$ Spectrum from 10 GeV to 3 TeV Measured by CALET on the ISS
• Isotropic diffuse and extragalactic $\gamma$-ray background: emission from extragalactic sources vs dark matter annihilating particles
• Extragalactic Searches for Dark Matter Annihilation
• The Anisotropies and Origins of Ultrahigh Energy Cosmic Rays