Prediction of the diffuse neutrino flux from cosmic ray interactions near Supernova Remnants

TL;DR

This study estimates the high-energy neutrino flux from 21 Galactic supernova remnants using gamma-ray data, suggesting that unresolved remnants could significantly contribute to the diffuse neutrino background detected by IceCube.

Contribution

First to derive a diffuse neutrino flux from a large sample of Galactic supernova remnants using gamma-ray and radio data, highlighting their potential role in the observed neutrino background.

Findings

Only the strongest SNRs could be detected as point sources by IceCube or KM3NeT.

The total diffuse neutrino flux from all SNRs is about 2.5 times higher than resolved sources.

Diffuse flux from SNRs at energies above 10 TeV can rival the interstellar medium contribution.

Abstract

In this paper, we present high-energy neutrino spectra from 21 Galactic supernova remnants (SNRs), derived from gamma-ray measurements in the GeV-TeV range. We find that only the strongest sources, i.e. G40.5-0.5 in the north and Vela Junior in the south could be detected as single point sources by IceCube or KM3NeT, respectively. For the first time, it is also possible to derive a diffuse signal by applying the observed correlation between gamma-ray emission and radio signal. Radio data from 234 supernova remnants listed in Green's catalog are used to show that the total diffuse neutrino flux is approximately a factor of 2.5 higher compared to the sources that are resolved so far. We show that the signal at above 10 TeV energies can actually become comparable to the diffuse neutrino flux component from interactions in the interstellar medium. Recently, the IceCube collaboration announced the detection of a first diffuse signal of astrophysical high-energy neutrinos. Directional information cannot unambiguously reveal the nature of the sources at this point due to low statistics. A number of events come from close to the Galactic center and one of the main questions is whether at least a part of the signal can be of Galactic nature. In this paper, we show that the diffuse flux from well-resolved SNRs is at least a factor of 20 below the observed flux.