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تسجيل مستخدم جديدIceCube Search for Dark Matter Annihilation in nearby Galaxies and Galaxy Clusters
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We present the results of a first search for self-annihilating dark matter in nearby galaxies and galaxy clusters using a sample of high-energy neutrinos acquired in 339.8 days of live time during 2009/10 with the IceCube neutrino observatory in its 59-string configuration. The targets of interest include the Virgo and Coma galaxy clusters, the Andromeda galaxy, and several dwarf galaxies. We obtain upper limits on the cross section as a function of the weakly interacting massive particle mass between 300 GeV and 100 TeV for the annihilation into b bbar, W+W-, tau+tau-, mu+mu-, and u u bar. A limit derived for the Virgo cluster, when assuming a large effect from subhalos, challenges the weak interacting massive particle interpretation of a recently observed GeV positron excess in cosmic rays.
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