Baryon Octet Electromagnetic Form Factors in a confining NJL model

Abstract

Electromagnetic form factors of the baryon octet are studied using a Nambu--Jona-Lasinio model which utilizes the proper-time regularization scheme to simulate aspects of colour confinement. In addition, the model also incorporates corrections to the dressed quarks from vector meson correlations in the t-channel and the pion cloud. Comparison with recent chiral extrapolations of lattice QCD results shows a remarkable level of consistency. For the charge radii we find the surprising result $r_E^p<r_E^{{\Sigma }^{+}}$ and $|r_E^n|<|r_E^{{\Xi }^0}|$, whereas the magnetic radii have a pattern largely consistent with a naive expectation based on the dressed quark masses.

Comments: 7 pages, 4 figures