# Gamma-Ray Puzzles in Cygnus X: Implications for High-Energy Neutrinos

## TL;DR

This paper models gamma-ray and neutrino emissions from Cygnus X, suggesting it could be a detectable source of high-energy neutrinos, revealing potential PeV accelerators in our galaxy.

## Contribution

It adapts a starburst galaxy cosmic ray interaction model to Cygnus X, estimating neutrino fluxes and comparing them with observations and sensitivities.

## Key findings

- Neutrino flux from Cygnus Cocoon could be detectable with current instruments.
- Gamma-ray emission models match observations from Fermi and ground-based observatories.
- Cygnus X may host PeV energy accelerators in the Galactic disk.

## Abstract

The Cygnus X region contains giant molecular cloud complexes and populous associates of massive young stars. The discovery of spatially extended, hard gamma-ray emission in Cygnus X by both Milagro and Fermi indicates that Cygnus X is also a potential source of high-energy Galactic neutrinos. Here, we adapt our single-zone model for cosmic ray interactions in the central molecular zones of starburst galaxies for use in Cygnus X. We calculate the potential neutrino flux corresponding to the hard gamma-ray emission from the "Cygnus Cocoon" and to the soft, diffuse interstellar gamma-ray emission. We check our results by comparing the corresponding gamma-ray emission against the Fermi interstellar emission model and Milagro, ARGO-YBJ, and HAWC observations. In comparing our results against a recent IceCube analysis and the current sensitivity limits, we find that neutrino emission from the Cocoon has a large enough flux that it could plausibly be detected, provided hadronic interactions are occurring at sufficiently high energies. High-energy neutrinos from Cygnus X would provide direct evidence for the presence of as yet unidentified PeV energy accelerators in the Galactic disk.