Constraints on flavor-dependent long-range interactions of high-energy astrophysical neutrinos

TL;DR

This paper investigates how flavor-dependent long-range interactions of neutrinos could influence their flavor composition after traveling cosmic distances, using current and future neutrino observatories to set constraints.

Contribution

It introduces a method to constrain flavor-dependent long-range neutrino interactions using astrophysical neutrino flavor measurements from IceCube and IceCube-Gen2.

Findings

Current measurements limit the strength of long-range neutrino interactions.

Future experiments will significantly improve sensitivity to these interactions.

Constraints depend on the precision of flavor composition and oscillation parameters.

Abstract

Astrophysical neutrinos with energy in the TeV-PeV range traverse megaparsecs (Mpc) to gigaparsecs (Gpc) scale distances before they reach the Earth. Tiny physics effects that get accumulated over these large propagation paths during their journey may become observable at the detector. If there is some new interaction between neutrinos and the background matter, that can potentially affect the propagation of the astrophysical neutrinos. One such possible case is the flavor-dependent long-range interaction of neutrinos, which can affect the standard neutrino flavor transition, modifying the flavor composition of the astrophysical neutrinos at Earth. Using the present-day and future projection of the flavor-composition measurements of IceCube and IceCube-Gen2 along with the present and future measurement of the oscillation parameters, we explore the sensitivity of these experiments to probe long-range neutrino interaction with matter.