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arXiv · 1509.03522

Evidence for the Galactic contribution to the IceCube astrophysical neutrino flux

A. Neronov·D. V. Semikoz
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Abstract

We show that the Galactic latitude distribution of IceCube astrophysical neutrino events with energies above 100~TeV is inconsistent with the isotropic model of the astrophysical neutrino flux. Namely, the Galactic latitude distribution of the events shows an excess at low latitudes |b|<10 degrees and a deficit at high Galactic latitude |b|> 50 degrees. We use Monte-Carlo simulations to show that the inconsistency of the isotropic signal model with the data is at > 3 sigma level, after the account of trial factors related to the choice of the low-energy threshold and Galactic latitude binning in our analysis.

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A. Neronov, D. V. Semikoz. 2015-09-11. Evidence for the Galactic contribution to the IceCube astrophysical neutrino flux. https://doi.org/10.1016/j.astropartphys.2015.11.002

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