# ANTARES neutrino search for time and space correlations with IceCube high-energy neutrino events

## TL;DR

This study searches for transient astrophysical neutrino sources by analyzing ANTARES and IceCube data for coincident events, finding no significant correlations but setting limits on potential source properties.

## Contribution

It introduces a combined analysis of ANTARES and IceCube data to constrain transient neutrino sources, providing new upper limits and spectral index constraints.

## Key findings

- No significant time-space correlations found.
- Upper limits set on neutrino fluence from IceCube directions.
- Spectral index constraints for potential transient sources.

## Abstract

In the past years, the IceCube Collaboration has reported in several analyses the observation of astrophysical high-energy neutrino events. Despite a compelling evidence for the first identification of a neutrino source, TXS 0506+056, the origin of the majority of these events is still unknown. In this paper, a possible transient origin of the IceCube astrophysical events is searched for using neutrino events detected by the ANTARES telescope. The arrival time and direction of 6894 track-like and 160 shower-like events detected over 2346 days of livetime are examined to search for coincidences with 54 IceCube high-energy track-like neutrino events, by means of a maximum likelihood method. No significant correlation is observed and upper limits on the one-flavour neutrino fluence from the direction of the IceCube candidates are derived. The non-observation of time and space correlation within the time window of 0.1 days with the two most energetic IceCube events constrains the spectral index of a possible point-like transient neutrino source, to be harder than $-2.3$ and $-2.4$ for each event, respectively.