Lattice Results on the Connected Neutron Charge Radius

TL;DR

This paper presents lattice QCD calculations of the neutron's electric form factor and charge radius, comparing results with experimental data and chiral perturbation theory to improve understanding of neutron structure.

Contribution

It provides the first quenched lattice QCD calculation of the connected neutron electric form factor over a range of momentum transfers and explores extrapolation methods to the chiral limit.

Findings

Calculated neutron charge radius consistent with experimental values.

Demonstrated the effectiveness of chiral perturbation theory in extrapolating lattice results.

Reconciled lattice results with phenomenological models.

Abstract

We describe a calculation using quenched lattice QCD of the connected part of the neutron electric form factor for momentum transfers in the range $0.3 {\rm GeV^2} \stackrel{<}{\sim} -q^2 \stackrel{<}{\sim} 1.0 {\rm GeV^2}$. We extract the implied charge radius using a Galster parameterization and consider various ways of extrapolating the neutron charge radius value to the chiral limit. We find that the measured charge radii may be reconciled to experiment by standard phenomenology and lowest or next to lowest order contributions from chiral perturbation theory.