Generalized Electric Polarizability of the Proton from Skyrme Model

Abstract

We calculate the electric polarizability $\alpha(q^2)$ of the proton in virtual Compton scattering using the Skyrme model. The $q^2$ dependence of the polarizability is comparable with the predictions obtained from the non-relativistic quark model and the linear sigma model. The chiral behaviors of our $\alpha(0)$ and $d^2\alpha(0)/d^2q^2$ agree with the results of the chiral perturbation theory. The discrepancy can be traced back to the contribution of the intermediate $\Delta$ state degenerate with the $N$ which is a characteristic of a large-$N_C$ model.