| Name: | Subhadip Bouri |
| Affiliation: | Indian Institute of Science |
| Conference ID : | ASI2024_367 |
| Title : | The First Search for High-Energy Neutrino Emission from Galaxy Mergers |
| Authors : | Subhadip Bouri1, Priyank Parashari1, Ranjan Laha1, Mousumi Das2 |
| Authors Affiliation: | 1 Subhadip Bouri, Priyank Parashari, Ranjan Laha Indian Institute of Science, Bangalore -560012, India
2 Mousumi Das Indian Institute of Astrophysics, Bangalore - 560034, India |
| Mode of Presentation: | Poster |
| Abstract Category : | High Energy Phenomena, Fundamental Physics and Astronomy |
| Abstract : | IceCube collaboration's discovery of diffuse high-energy astrophysical neutrinos has opened up a new and complementary way to probe the Universe. Although there is detection of neutrino flux from two high energy point sources, TXS 0506+056 and NGC 1068, we do not yet know the source classes which mainly contribute to the diffuse flux. The presence of the high-energy neutrino flux implies that there are possible hadronic accelerators in the Universe. A knowledge of these astrophysical production sites will accelerate our knowledge of both astrophysics and particle physics (both Standard Model and beyond the Standard Model physics). Many possible sources of these neutrinos, like active galactic nuclei, pulsars, etc., have been studied in the literature. Using the published IceCube data set, we conduct the first study on whether galaxy mergers can be the sources of the TeV-PeV astrophysical neutrinos. Galaxy mergers can host very high-energy hadronic and photohadronic processes, which may lead to these neutrino emissions. We perform an unbinned maximum-likelihood-ratio analysis for six galaxy merger catalogs with 10 years of public IceCube muon-track data. We analyze the significance of each galaxy merger location in the catalogs and find that none of the galaxy mergers in all catalogs has a large global significance. We also study the correlation of all-sky diffuse astrophysical neutrinos with the catalogs by stacking the sources together. Our stacking analyses show no significant correlation between the galaxy mergers and IceCube neutrinos with the current data set. We conclude that known galaxy mergers from the catalogs do not contribute significantly to the diffuse neutrino flux detected by IceCube. Our study implies strong constraints on very high-energy hadronic cosmic-ray acceleration in galaxy mergers. Near future search of neutrinos from galaxy mergers can either discover their neutrino production or produce more stringent constraints on their very high-energy hadronic acceleration mechanism. |
