101. Dark Matter Searches in the Gamma-ray Extragalactic Background via Cross-correlations with Galaxy Catalogs
- Author
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Marco Regis, Alessandro Cuoco, Jun Qing Xia, Matteo Viel, Enzo Branchini, Nicolao Fornengo, USA, Cuoco, Alessandro, Xia, Jun Qing, Regis, Marco, Branchini, ENZO FRANCO, Fornengo, Nicolao, and Viel, Matteo
- Subjects
cosmology: observations ,cosmology: theory ,dark matter ,gamma-rays: diffuse backgrounds ,large-scale structure of universe ,Space and Planetary Science ,Astronomy and Astrophysics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Active galactic nucleus ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,Dark matter ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Halo occupation distribution ,Radio continuum: galaxies ,High Energy Physics - Phenomenology (hep-ph) ,diffuse background [gamma-rays] ,Settore FIS/05 - Astronomia e Astrofisica ,WIMP ,Astrophysics::Galaxy Astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,NRAO VLA Sky Survey ,Physics ,theory [cosmology] ,Astrophysics::Instrumentation and Methods for Astrophysics ,Galaxies: evolution ,Quasar ,Galaxies: starburst ,Infrared: galaxies ,Radiation mechanisms: general ,Galaxy ,High Energy Physics - Phenomenology ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Cosmology and Nongalactic Astrophysics ,observation [cosmology] - Abstract
We compare the measured angular cross-correlation between the Fermi-LAT gamma-ray sky and catalogues of extra-galactic objects with the expected signal induced by weakly interacting massive particle (WIMP) dark matter (DM). We include a detailed description of the contribution of astrophysical gamma-ray emitters such as blazars, misaligned AGN and star forming galaxies, and perform a global fit to the measured cross-correlation. Five catalogues are considered: SDSS-DR6 quasars, 2MASS galaxies, NVSS radio galaxies, SDSS-DR8 Luminous Red Galaxies and SDSS-DR8 main galaxy sample. To model the cross-correlation signal we use the halo occupation distribution formalism to estimate the number of galaxies of a given catalogue in DM halos and their spatial correlation properties. We discuss uncertainties in the predicted cross-correlation signal arising from the DM clustering and WIMP microscopic properties, which set the DM gamma-ray emission. The use of different catalogues probing objects at different redshifts reduces significantly, though not completely, the degeneracy among the different gamma-ray components. We find that the presence of a significant WIMP DM signal is allowed by the data but not significantly preferred by the fit, although this is mainly due to a degeneracy with the misaligned AGN component. With modest substructure boost, the sensitivity of this method excludes thermal annihilation cross sections at 95% C.L. for WIMP masses up to few tens of GeV. Constraining the low-redshift properties of astrophysical populations with future data will further improve the sensitivity to DM., Comment: 24 pages, 19 figures, 2 tables, 4 appendices. V2:updated to match published version in ApJS
- Published
- 2015