Exploring IceCube Neutrino Alerts with the HAWC Observatory

Ian Herzog

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arXiv · 2508.00090

Exploring IceCube Neutrino Alerts with the HAWC Observatory

Ian Herzog

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Abstract

While much work has gone into associating neutrino emission with various sources, very few sources have emerged. With the recent publication of IceCube Event Catalog (IceCat-1), the IceCube neutrino observatory has released a list of the most promising astrophysical neutrino events since operations began in 2010. Using the archival data from the High Altitude Water Cherenkov (HAWC) gamma-ray observatory, we perform a coincidence search for gamma rays and neutrinos using a Bayesian Block algorithm with the public IceCube alerts from IceCat-1 and the Astrophysical Multi-messenger Observatory Network (AMON). Of the 350 alerts considered, 25 detections were found, with 1 coinciding with the flaring HAWC source Markarian 421, an active galactic nuclei. We present the performance of this method and a discussion of physics implications.

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Ian Herzog. 2025-07-31. Exploring IceCube Neutrino Alerts with the HAWC Observatory. https://arxiv.org/abs/2508.00090

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