Chiral extrapolation of octet-baryon charge radii

TL;DR

This paper uses heavy-baryon chiral perturbation theory with finite-range regularization to extrapolate lattice-QCD charge radii of octet-baryons, achieving good agreement with experimental data for some baryons and predicting others for future measurement.

Contribution

It introduces a novel application of finite-range regularization in chiral extrapolation of lattice-QCD data for octet-baryon charge radii, improving convergence and estimating quenching effects.

Findings

Charge radii of proton, neutron, and Sigma- agree with experiments.

Predicted charge radii of other octet-baryons are provided for future tests.

Finite-range regularization enhances chiral extrapolation accuracy.

Abstract

The charge radii of octet-baryons obtained in quenched lattice-QCD calculations are extrapolated within heavy-baryon chiral perturbation theory. Finite-range regularization (FRR) is applied to improve the convergence of the chiral expansion and to provide estimates of quenching artifacts. Lattice values of quark distribution radii and baryon charge radii for $\mpi^2$ in the range (0.1, 0.7)$\gev^2$ are described very well with FRR. Upon estimating corrections for both finite-volume and quenching effects, the obtained charge radii of the proton, neutron and $\Sigma^-$ are in good agreement with experimental measurements. The predicted charge radii of the remaining octet-baryons have not yet been measured and present a challenge to future experiments.