Sub-PeV Neutrinos from TeV Unidentified Sources in the Galaxy
Abstract
The IceCube collaboration discovery of 28 high-energy neutrinos over the energy range 30 TeV <~ ɛν <~ 1 PeV, a 4.3σ excess over expected backgrounds, represents the first high-confidence detection of cosmic neutrinos at these energies. In light of this discovery, we explore the possibility that some of the sub-PeV cosmic neutrinos might originate 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. Modeling the TeV UnID sources as Galactic hypernova remnants, we predict sub-PeV neutrino fluxes and spectra consistent with their contributing a minority of n ν <~ 2 of the observed events. This is consistent with our analysis of the spatial distribution of the sub-PeV neutrinos and TeV UnID sources, which finds that a best-fit of one, and maximum of 3.8 (at 90% confidence), of the ≈16 non-atmospheric sub-PeV neutrinos may originate in the TeV UnID sources, with the remaining 75%-95% of events being drawn from an isotropic background. If our scenario is correct, we expect excess sub-PeV neutrinos to accumulate along the Galactic plane, within |l| <~ ± 30° of the Galactic center and in the Cygnus region, as observations by IceCube and other high-energy neutrino facilities go forward. Our scenario also has implications for radio, X-ray, and TeV observations of the TeV UnID sources.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2013
- DOI:
- 10.1088/0004-637X/774/1/74
- arXiv:
- arXiv:1305.6606
- Bibcode:
- 2013ApJ...774...74F
- Keywords:
-
- cosmic rays;
- gamma rays: general;
- ISM: supernova remnants;
- neutrinos;
- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Experiment;
- High Energy Physics - Phenomenology
- E-Print:
- Submitted to ApJ. 17 pages, 2 figures. v3: Revised analysis, conclusions