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arXiv · 1603.06733

Galactic and extragalactic contributions to the astrophysical muon neutrino signal

A. Neronov·D. V. Semikoz
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Abstract

Spectral and anisotropy properties of IceCube astrophysical neutrino signal reveal an evidence for a significant Galactic contribution to the neutrino flux in Southern hemisphere. We check if the Galactic contribution is detectable in the astrophysical muon neutrino flux observed from a low positive declinations region of the Northern sky. Estimating the Galactic neutrino flux in this part of the sky from gamma-ray and Southern sky neutrino data, we find that the Northern sky astrophysical muon neutrino signal shows an excess over the Galactic flux. This points to the presence of an additional hard spectrum (extragalactic or large scale Galactic halo) component of astrophysical neutrino flux. We show that the Galactic flux component should still be detectable in the muon neutrino data in a decade long IceCube exposure.

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A. Neronov, D. V. Semikoz. 2016-03-22. Galactic and extragalactic contributions to the astrophysical muon neutrino signal. https://doi.org/10.1103/physrevd.93.123002

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