Search for Neutrinos from the Galactic 4FGL Sources with the Pion-bump Signature with IceCube

TL;DR

This study searches for neutrinos from 56 Galactic sources with pion-bump signatures using 13 years of IceCube data, aiming to identify specific cosmic-ray acceleration sites within the Milky Way.

Contribution

It is the first comprehensive search for neutrinos from 4FGL sources with pion-bump features, utilizing extensive IceCube data to probe Galactic cosmic-ray accelerators.

Findings

No significant neutrino signals detected from the sources.

Constraints placed on neutrino fluxes from these sources.

Results inform models of cosmic-ray acceleration in the Galaxy.

Abstract

The IceCube Neutrino Observatory, located at the South Pole, covers a cubic kilometer of Antarctic ice, and is designed to detect astrophysical neutrinos in the TeV-PeV energy range. While IceCube has recently identified a diffuse flux of neutrinos originating from the Galactic Plane, specific sources of astrophysical neutrinos within the Milky Way remain elusive. Hadronic gamma-rays, produced through the decay of neutral pions, are expected to display a characteristic "pion bump" or "spectral break" around 200 MeV. Recent studies by the Fermi-LAT Collaboration highlight 56 sources from the 4FGL Catalog exhibiting a spectral break in the MeV energy range. Detecting astrophysical neutrinos from these sources would provide compelling evidence for cosmic-ray acceleration in their vicinity. In this analysis, we search for astrophysical neutrino emission from 56 sources showing characteristics of a pion bump using 13 years of IceCube data. Our findings could enhance our understanding of potential cosmic-ray acceleration sites in the galaxy.