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arXiv · 1511.01708

Search for Galactic disk and halo components in the arrival directions of high-energy astrophysical neutrinos

Sergey Troitsky
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Abstract

Arrival directions of 40 neutrino events with energies >~100 TeV, observed by the IceCube experiment, are studied. Their distribution in the Galactic latitude and in the angular distance to the Galactic Center allow to search for the Milky-Way disk and halo-related components, respectively. No statistically significant evidence for the disk component is found, though even 100% disk origin of the flux is allowed at the 90% confidence level. Contrary, the Galactic Center-Anticenter dipole anisotropy, specific for dark-matter decays (annihilation) or for interactions of cosmic rays with the extended halo of circumgalactic gas, is clearly favoured over the isotropic distribution (the probability of a fluctuation of the isotropic signal is ~2%).

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Sergey Troitsky. 2015-11-05. Search for Galactic disk and halo components in the arrival directions of high-energy astrophysical neutrinos. https://doi.org/10.1134/s0021364015240133

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