Search for Extended Sources of Neutrino Emission in the Galactic Plane with IceCube

TL;DR

This study uses 10 years of IceCube data to search for extended neutrino sources in the Galactic plane, finding no significant emission but setting constraints on hadronic cosmic-ray interactions.

Contribution

First dedicated search for extended neutrino sources in the Galactic plane using a decade of IceCube data, focusing on regions with gamma-ray evidence of cosmic-ray acceleration.

Findings

No significant neutrino emission detected from studied regions.

Most significant excess is 2.6σ at a specific gamma-ray source location.

Constraints placed on hadronic emission models in the Galactic plane.

Abstract

The Galactic plane, harboring a diffuse neutrino flux, is a particularly interesting target to study potential cosmic-ray acceleration sites. Recent gamma-ray observations by HAWC and LHAASO have presented evidence for multiple Galactic sources that exhibit a spatially extended morphology and have energy spectra continuing beyond 100 TeV. A fraction of such emission could be produced by interactions of accelerated hadronic cosmic rays, resulting in an excess of high-energy neutrinos clustered near these regions. Using 10 years of IceCube data comprising track-like events that originate from charged-current muon neutrino interactions, we perform a dedicated search for extended neutrino sources in the Galaxy. We find no evidence for time-integrated neutrino emission from the potential extended sources studied in the Galactic plane. The most significant location, at 2.6$\sigma$ post-trials, is a 1.7$^\circ$ sized region coincident with the unidentified TeV gamma-ray source 3HWC J1951+266. We provide strong constraints on hadronic emission from several regions in the Galaxy.