Speaker
Description
Gamma-ray observations of astrophysical neutrino sources are crucial to understanding particle acceleration and neutrino production in extreme cosmic environments. The Cherenkov Telescope Array Observatory (CTAO), currently under construction, will cover 20 GeV–300 TeV, providing unprecedented sensitivity to both steady and transient gamma-ray emitters.
Within the CTAO Neutrino Target of Opportunity (NToO) program, follow-up studies were initially based on alerts from IceCube. In this work, we compare the prospects of using IceCube and KM3NeT, whose ARCA detector greatly improves sensitivity to high-energy neutrinos from the Southern Hemisphere. Using the open-source code FIRESONG, we simulate populations of steady and flaring extragalactic neutrino sources to assess CTAO’s ability to detect their gamma-ray counterparts.
Our results show that the combined CTAO–KM3NeT approach significantly outperforms CTAO–IceCube follow-up, particularly for sources in the Southern Hemisphere. This study provides the first quantitative assessment of CTAO’s potential to detect very-high-energy gamma-ray counterparts of both steady and transient neutrino sources, highlighting the key role of KM3NeT in enabling comprehensive Southern-sky multi-messenger astronomy.