Interactions of Neutrino Wave Packets

TL;DR

This paper investigates how neutrino wave packet sizes influence their scattering interactions, revealing that interactions become trivial for plane waves unless finite wave packet effects are included, especially in dense environments.

Contribution

It introduces a continuum limit approach for neutrino interactions and emphasizes the significance of wave packet sizes in neutrino scattering analysis.

Findings

Interactions trivial for plane waves in the continuum limit

Finite wave packet sizes are crucial for realistic neutrino scattering

Wave packet effects impact neutrino behavior in dense environments

Abstract

The low energy effective field theory of interacting neutrinos derived from the Standard Model may be framed as a pointlike interaction and thereby modeled on a lattice of neutrino momenta. We identify a path to take a continuum limit of this lattice problem in the center of momentum frame. In this limit, the weak interaction is found to become trivial between incoming plane waves describing ultrarelativistic particles, unless finite neutrino wave packet sizes are taken into consideration. We follow up with an analytic treatment of interacting neutrino wave packets, demonstrating the importance of the wave packet size for characterizing neutrino-neutrino scattering in dense environments.