The charge radii of octet-baryons obtained in quenched lattice-QCD calculations are extrapolated within heavy-baryon chiral perturbation theory. Finite-range regularization 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 $m_{\pi }^2$ in the range $(0.1,0.7){\mathrm{GeV}}^2$ are described very well with finite-range regularization. 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.

• Received 6 October 2008

DOI:https://doi.org/10.1103/PhysRevD.79.094001