Nucleon axial-vector form factor and radius from radiatively-corrected antineutrino scattering data

TL;DR

This paper refines the extraction of the nucleon axial-vector form factor and radius from recent antineutrino scattering data by applying radiative corrections, facilitating better comparison with lattice QCD predictions.

Contribution

It introduces radiative correction procedures to extract $G_A$ and its radius from experimental data, improving the accuracy of these fundamental quantities.

Findings

Radiative corrections significantly affect the extracted $G_A$ and radius.

Comparison with lattice QCD shows consistency within uncertainties.

The work highlights the importance of corrections for future neutrino scattering analyses.

Abstract

The nucleon axial-vector form factor, $G_A$, is critical to determine the electroweak interactions of leptons with nucleons. Important examples of processes influenced by $G_A$ are elastic (anti)neutrino-nucleon scattering and muon capture by the proton. Sparse experimental data results in a large uncertainty on the momentum dependence of $G_A$ and has motivated the consideration of new experimental probes and first-principles lattice quantum chromodynamics (QCD) evaluations. The comparison of new and precise theoretical predictions for $G_A$ with future experimental data necessitates the application of radiative corrections to experimentally-observable processes. We apply these corrections in the extraction of $G_A$ and the associated axial-vector radius from the recent MINERvA antineutrino-hydrogen data, compare the effects from radiative corrections to other uncertainties in neutrino scattering experiments, and discuss the comparison of lattice QCD evaluations to experimental measurements.