1305.6606 (D. B. Fox et al.)

Sub-PeV Neutrinos from TeV Unidentified Sources in the Galaxy    [PDF]

D. B. Fox, K. Kashiyama, P. Meszaros

The IceCube collaboration discovery of 28 high-energy neutrinos over the energy range 30 TeV <~ e_nu <~ 1 PeV, a 4.3-sigma excess over expected backgrounds, represents the first high-confidence detection of cosmic neutrinos at these energies. In light of this discovery, we construct a model for generating sub-PeV cosmic neutrinos in our Galaxy's TeV unidentified (TeV UnID) sources. While typically resolved at TeV energies, these sources lack prominent radio or X-ray counterparts, and so have been considered promising sites for hadron acceleration within our Galaxy. We find that the flux and power-law spectrum of the Sub-PeV neutrinos are consistent with predictions for the TeV UnID sources, which we model as Galactic hypernova remnants; in our model, the ~1.5 PeV cutoff in the neutrino spectrum indicates acceleration of hadrons to E_max >~ 10 PeV. Exploring the spatial distribution of the Sub-PeV neutrinos and TeV UnID sources, we find that a best-fit of two, and maximum of 6.4 (at 90%-confidence), of the Sub-PeV neutrinos may originate in the Galaxy's TeV UnID sources, with the remaining 60% to 90% of events being drawn from an isotropic background. If our scenario is correct, we expect a track-type IceCube Sub-PeV neutrino to be found in coincidence with one of the TeV UnID sources within the next 0.5 to 3.5 years of IceCube observations. Our scenario can be further tested via observations of Sub-PeV neutrinos from ANTARES and other neutrino facilities, and has implications for radio, X-ray, and TeV observations of the TeV UnID sources.

View original: http://arxiv.org/abs/1305.6606