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Dark matter and pulsar signals for Fermi LAT, PAMELA, ATIC, HESS and WMAP data

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 نشر من قبل Danny Marfatia
 تاريخ النشر 2009
  مجال البحث فيزياء
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We analyze new diffuse gamma-ray data from the Fermi Gamma-ray Space Telescope, which do not confirm an excess in the EGRET data at galactic mid-latitudes, in combination with measurements of electron and positron fuxes from PAMELA, Fermi and HESS within the context of three possible sources: dark matter (DM) annihilation or decay into charged leptons, and a continuum distribution of pulsars. We allow for variations in the backgrounds, consider several DM halo profiles, and account for systematic uncertainties in data where possible. We find that all three scenarios represent the data well. The pulsar description holds for a wide range of injection energy spectra. We compare with ATIC data and the WMAP haze where appropriate, but do not fit these data since the former are discrepant with Fermi data and the latter are subject to large systematic uncertainties. We show that for cusped halo profiles, Fermi could observe a spectacular gamma-ray signal of DM annihilation from the galactic center while seeing no excess at mid-latitudes.



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