Speaker: Dra. Maria Petropavlova

Institution: Institute of Experimental and Applied Physics, Czech Technical University in Prague

Title: Constraints on Neutrino Secret Interactions from Multi-messenger neutrinos scattering on CνB

Date: Miércoles 9 de abril, 14:30 hrs (Chile Continental)

Abstract: We present new constraints on neutrino secret interactions (νSI) using high-energy and ultra high-energy astrophysical neutrinos as probes of new physics beyond the Standard Model. By studying neutrinos from established sources, such as SN1987A, NGC 1068, TXS 0506+056, PKS 0735+178, and the extreme-energy KM3-230213A event, we explore the potential interactions of Dirac neutrinos with a massive spin-one boson during their propagation through the Cosmic Neutrino Background (CνB). Notably, the KM3-230213A event allows us to probe an entirely new scale of interaction strength and reveals sensitivity to heavier mediator masses previously beyond reach.

Our analysis covers both ultra-relativistic and non-relativistic regimes, deriving exclusion limits on the νSI coupling constant across the full mediator mass range. We examine flavor-universal and flavor-non-universal coupling scenarios, the latter are often addressed in discussions about cosmological tensions such as H₀ and S₈ discrepansies. This work contributes to the ongoing development of the theoretical framework for νSI and illustrates the potential of multi-messenger neutrino observations to probe fundamental aspects of neutrino interactions.