Coherent collision integrals for neutrino transport equations

TL;DR

This paper develops quantum kinetic equations and Feynman rules for neutrino transport that incorporate flavor and particle-antiparticle coherence, enabling more accurate modeling of neutrino interactions in astrophysical environments.

Contribution

It introduces a unified framework for calculating neutrino collision rates with coherence effects, extending traditional methods to include mixing and coherence phenomena.

Findings

Derived Feynman rules for coherent neutrino scattering

Provided explicit collision integral examples for supernova neutrinos

Enhanced the computational tools for neutrino transport modeling

Abstract

We present quantum kinetic equations for neutrinos and derive Feynman rules for computing scattering rates involving coherent states. Our rules encompass both flavour- and particle-antiparticle coherence and allow writing down the scattering matrix elements and collision integrals with the same intuitive ease as with the usual non-coherent Feynman rules. Our results are useful for computing collision rates that arise routinely in the context of coherently mixing neutrinos with arbitrary masses. We give several explicit examples, including some collision integrals for coherently mixing neutrinos in supernovae.