Prospects for Detecting Gamma Rays from Annihilating Dark Matter in Dwarf Galaxies in the Era of DES and LSST

Abstract

Among the most stringent constraints on the dark matter annihilation cross section are those derived from observations of dwarf galaxies by the Fermi Gamma-Ray Space Telescope. As current (e.g., Dark Energy Survey, DES) and future (Large Synoptic Survey Telescope, LSST) optical imaging surveys discover more of the Milky Way's ultra-faint satellite galaxies, they may increase Fermi's sensitivity to dark matter annihilations. In this study, we use a semi-analytic model of the Milky Way's satellite population to predict the characteristics of the dwarfs likely to be discovered by DES and LSST, and project how these discoveries will impact Fermi's sensitivity to dark matter. While we find that modest improvements are likely, the dwarf galaxies discovered by DES and LSST are unlikely to increase Fermi's sensitivity by more than a factor of ~2-4. However, this outlook may be conservative, given that our model underpredicts the number of ultra-faint galaxies with large potential annihilation signals actually discovered in the Sloan Digital Sky Survey. Our simulation-based approach focusing on the Milky Way satellite population demographics complements existing empirically-based estimates.

6 pages, 3 figures, submitted to Phys. Rev. D

References in corpus (12)

• Dark Matter Constraints from Observations of 25 Milky Way Satellite Galaxies with the Fermi Large Area Telescope
• Hundreds of Milky Way Satellites? Luminosity Bias in the Satellite Luminosity Function
• The Luminosity Function of the Milky Way Satellites
• Precise constraints on the dark matter content of Milky Way dwarf galaxies for gamma-ray experiments
• The Invisibles: A Detection Algorithm to Trace the Faintest Milky Way Satellites
• The Most Dark Matter Dominated Galaxies: Predicted Gamma-ray Signals from the Faintest Milky Way Dwarfs
• Indirect Dark Matter Detection from Dwarf Satellites: Joint Expectations from Astrophysics and Supersymmetry
• Too Many, Too Few, or Just Right? The Predicted Number and Distribution of Milky Way Dwarf Galaxies
• H.E.S.S. constraints on Dark Matter annihilations towards the Sculptor and Carina Dwarf Galaxies
• Stringent Constraints On The Dark Matter Annihilation Cross Section From Subhalo Searches With The Fermi Gamma-Ray Space Telescope
• Dark matter in the classical dwarf spheroidal galaxies: a robust constraint on the astrophysical factor for gamma-ray flux calculations
• Dark Matter annihilation in Draco: new considerations of the expected gamma flux

Cited by in corpus (11)

• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data
• A Comprehensive Search for Dark Matter Annihilation in Dwarf Galaxies
• Indication of Gamma-ray Emission from the Newly Discovered Dwarf Galaxy Reticulum II
• Sensitivity Projections for Dark Matter Searches with the Fermi Large Area Telescope
• Snake in the Clouds: A new nearby dwarf galaxy in the Magellanic bridge
• On The Gamma-Ray Emission From Reticulum II and Other Dwarf Galaxies
• Ships Passing in the Night: Spectroscopic Analysis of Two Ultra-Faint Satellites in the Constellation Carina
• Search for Gamma-ray Emission from Dark Matter Annihilation in the Large Magellanic Cloud with the Fermi Large Area Telescope
• Indirect Dark Matter Detection for Flattened Dwarf Galaxies
• Analysis of Fermi-LAT data from Tucana-II: Possible constraints on the Dark Matter models with an intriguing hint of a signal