Radiative corrections to neutron beta decay and (anti)neutrino-nucleon scattering from low-energy effective field theory

TL;DR

This paper develops a systematic approach using effective field theory to accurately compute radiative corrections in neutron beta decay and neutrino-nucleon scattering, clarifying scheme dependence and separating short- and long-distance effects.

Contribution

It introduces a top-down effective field theory framework that relates low-energy constants to correlation functions, improving the precision of radiative correction calculations.

Findings

Explicit relations between low-energy constants and correlation functions.

Clarification of scheme dependence in radiative corrections.

Robust predictions of electromagnetic contributions.

Abstract

We study radiative corrections to neutron beta decay and low-energy (anti)neutrino-nucleon scattering within a top-down effective field theory approach. As it was recently shown, a few electromagnetic and electroweak low-energy coupling constants in heavy-baryon chiral perturbation theory are yet to be determined. Performing matching to the four-fermion effective field theory, we relate these low-energy constants to correlation functions of vector and axial-vector currents. Such relations allow us to explicitly clarify scheme dependence for radiative corrections to neutron decay and low-energy charged-current (anti)neutrino scattering, provide a robust prediction of leading in the electromagnetic coupling constant contributions, and achieve a clear separation between short-distance and long-distance contributions.