skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Prospects for annihilating Dark Matter towards Milky Way's dwarf galaxies by the Cherenkov Telescope Array

Journal Article · · Journal of Cosmology and Astroparticle Physics
 [1]; ;  [2]
  1. IRFU/DSM, CEA Saclay, F-91191 Gif-sur-Yvette (France)
  2. Institut d'Astrophysique de Paris, UMR 7095 (CNRS and UPMC, Sorbonne Universités), 98 bis Boulevard Arago, Paris F-75014 (France)

We derive the Cherenkov Telescope Array (CTA) sensitivity to dark matter (DM) annihilation in several primary channels, over a broad range of DM masses. These sensitivities are estimated when CTA is pointed towards a large sample of Milky Way's dwarf spheroidal galaxies (dSphs) with promising J -factors and small statistical uncertainties. This analysis neglects systematic uncertainties, which we estimate at the level of at least 1 dex. We also present sensitivities on the annihilation cross section from a combined analysis of 4 dSphs. We assess the CTA sensitivity by: i ) using, for each dSph, a recent determination of the J -factor and its statistical error; ii ) considering the most up-to-date cosmic ray background; and iii ) including both spatial and spectral terms in the likelihood analysis. We find that a joint spectral and spatial analysis improves the CTA sensitivity, in particular for primary channels with sharp features in the γ-ray energy spectrum and for dSphs with steep J -factor profiles, as deduced from the internal kinematics. The greatest sensitivities are obtained for observations of Ursa Minor among the classical dSphs and of Ursa Major II for ultra-faint dSphs.

OSTI ID:
22679465
Journal Information:
Journal of Cosmology and Astroparticle Physics, Vol. 2016, Issue 09; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
Country of Publication:
United States
Language:
English