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arXiv · 2609.22577

Resolving the Galactic Center Region's Gamma-Ray Emission and Searching for its Neutrino Counterpart with HAWC and IceCube

S. Yun-Carcamo·R. Babu·for the HAWC·IceCube collaborations
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Abstract

The Galactic Center (GC) is a prime candidate for petaelectronvolt cosmic-ray acceleration, with gamma-ray emission observed by the High Altitude Water Cherenkov (HAWC) Observatory extending beyond 100 TeV. We present an analysis of the GC using ~2860 days of HAWC data, with increased exposure and improved sensitivity relative to previous results. The best-fit gamma-ray emission model includes a point source (HAWC J1745-2857) and a Galactic diffuse emission component. Assuming a hadronic origin, we construct the corresponding neutrino signal template and search for it in 12 years of IceCube muon-track data. No significant neutrino excess is found, and we report the first upper limit on the high-energy neutrino flux associated with the multi-component spatial model of the GC derived from HAWC data. The limit is approximately 12 times the nominal neutrino flux predicted from the HAWC gamma-ray model under a hadronic interpretation, and therefore it does not yet test the optically thin hadronic scenario.

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S. Yun-Carcamo, R. Babu, for the HAWC, IceCube collaborations. 2026-09-18. Resolving the Galactic Center Region's Gamma-Ray Emission and Searching for its Neutrino Counterpart with HAWC and IceCube. https://arxiv.org/abs/2609.22577

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