The exact sources of high-energy neutrinos detected by the IceCube neutrino observatory still remain a mystery. In this talk, I will explore the hypothesis that galaxy mergers may serve as sources for these high-energy neutrinos. Galaxy mergers can host very high-energy hadronic and photohadronic processes, which may produce very high-energy neutrinos. I will discuss that we perform an unbinned maximum-likelihood-ratio analysis utilizing the galaxy merger data from six catalogs and 10 years of public IceCube muon-track data to quantify any correlation between these mergers and neutrino events. First, we perform the single source search analysis, which reveals that none of the considered galaxy mergers exhibit a statistically significant correlation with high-energy neutrino events detected by IceCube. Furthermore, we conduct a stacking analysis with three different weighting schemes to understand if these galaxy mergers can contribute significantly to the diffuse flux of high-energy astrophysical neutrinos detected by IceCube. We find that upper limits (at 95% c.l.) of the all-flavour high-energy neutrino flux, associated with galaxy mergers considered in this study, at 100 TeV with spectral index Γ=−2 are 2.57×10^−18, 8.51×10^−19, and 2.36×10^−18 GeV^−1cm^-2s^−1sr^−1 for the three weighting schemes. I will discuss preliminary results on gamma-ray counterparts from the galaxy mergers.
Wednesday
2 Oct/24
11:30
-
12:30
(Europe/Zurich)
First Search for High-Energy Neutrino and Gamma-Ray Emission from Galaxy Mergers
Where:
4/2-011 - TH common room at CERN