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arXiv · 0705.1315

Multi-year search for a diffuse flux of muon neutrinos with AMANDA-II

IceCube Collaboration·A. Achterberg
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Abstract

A search for TeV - PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent livetime of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with non-thermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E^{2}Φ_{90% C.L.} < 7.4 x 10^{-8} GeV cm^{-2} s^{-1} sr^{-1} is placed on the diffuse flux of muon neutrinos with a Φ\propto E^{-2} spectrum in the energy range 16 TeV to 2.5 PeV. This is currently the most sensitive Φ\propto E^{-2} diffuse astrophysical neutrino limit. We also set upper limits for astrophysical and prompt neutrino models, all of which have spectra different than Φ\propto E^{-2}.

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IceCube Collaboration, A. Achterberg. 2008-04-13. Multi-year search for a diffuse flux of muon neutrinos with AMANDA-II. https://doi.org/10.1103/physrevd.76.042008%2010.1103%2Fphysrevd.77.089904

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