# AMON: TeV Gamma and Neutrino Coincidence Alerts from HAWC and IceCube subthreshold data

## TL;DR

This paper presents AMON's implementation of a joint analysis of TeV gamma-ray and neutrino subthreshold data to generate real-time coincidence alerts, enhancing multimessenger astrophysics capabilities.

## Contribution

It introduces a novel joint-likelihood analysis combining HAWC gamma-ray data and IceCube neutrino data for real-time multimessenger alerts.

## Key findings

- Successful implementation of joint-likelihood analysis
- Real-time coincidence alerts with 0.2° angular resolution
- Potential to increase multimessenger observation rates

## Abstract

The era of multimessenger astrophysics has arrived with the simultaneous operation of large cosmic-ray, gamma-ray, neutrino, and gravitational-wave observatories. In just the past two years, an electromagnetic (EM) counterpart was detected for a gravitational wave event, and evidence for an EM counterpart of high energy neutrinos has been identified. These measurements have had a major impact on our view of the non-thermal universe, but understanding cosmic accelerators require a substantial increase in the number of multimessenger observations. The Astrophysical Multimessenger Observatory Network (AMON) is designed for high-statistics searches of sub-threshold transient alerts from gamma-ray and neutrino detectors. Within AMON, we have implemented a joint-likelihood analysis of TeV gamma-ray measurements from the High Altitude Water Cherenkov (HAWC) Observatory and neutrinos from the IceCube Neutrino Observatory. AMON is ready to produce real-time coincidence alerts using HAWC "hotspots" and IceCube astrophysical neutrino events. These alerts will be distributed to AMON follow-up partners with a median anticipated delay of six hours, which corresponds to a full transit in the field of view of HAWC. The alerts will have an angular resolution of ${\sim}0.2^{\circ}$, making them well-suited for deep electromagnetic follow-up observations.