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arXiv · 2105.13378

Hot spots in the neutrino flux created by cosmic rays from Cygnus and Vela?

Abstract

An analysis of 7.5 years of data in the high-energy starting event sample has been recently published by the IceCube collaboration. The hottest spot in a search for neutrino sources was found far above the Galactic plane and is thus, at first sight, difficult to reconcile with a Galactic origin. In this work, we calculate the cosmic ray (CR) density around nearby, young supernova remnants assuming anisotropic diffusion. Combining the obtained CR densities with the matter distribution deduced from extinction maps, we find two prominent hot spots: The one close to the most significant point in the IceCube search for point sources is created by CRs from the Cygnus loop and has an intensity corresponding to two to four neutrino events. Another, more extended one may be caused by CRs from Vela if CR trajectories are sufficiently disturbed by the magnetic field in the shell around the superbubble Loop I.

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M. Bouyahiaoui, M. Kachelriess, D. V. Semikoz. 2022-08-30. Hot spots in the neutrino flux created by cosmic rays from Cygnus and Vela?. https://doi.org/10.1103/physrevd.106.063004

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