Quantum field-theoretic framework for neutrino decoherence from scattering in a medium

TL;DR

This paper introduces a quantum field-theoretic framework for neutrino decoherence caused by scattering in a medium, linking decoherence effects to scattering cross sections and exploring implications for neutrino oscillations and new physics.

Contribution

It develops a generalized Lindblad master equation for neutrino evolution that includes momentum-changing scattering processes, extending previous fixed-momentum models.

Findings

Decoherence can significantly modify neutrino oscillation patterns.

The formalism connects decoherence parameters directly to scattering cross sections.

Results provide a new way to probe physics beyond the Standard Model.

Abstract

We develop a theoretical framework for quantum field description of neutrino evolution in a medium, with a focus on quantum decoherence induced by neutrino scattering on fermions. By deriving a generalized Lindblad master equation that accounts for neutrino momentum-changing transitions, we go beyond the standard treatment that assumes fixed neutrino momentum. Our model explicitly connects decoherence parameters to scattering cross sections, offering a bridge between theoretical predictions and experimental constraints on neutrino quantum decoherence. We apply the developed formalism to several scenarios: 1) neutrino scattering on electrons, 2) neutrino scattering on protons and neutrons through non-standard interactions (NSI), 3) neutrino scattering on dark matter fermions. The obtained results demonstrate that decoherence effects can significantly alter neutrino oscillation patterns and provide a new probe for physics beyond the Standard Model.