Chiral quark soliton model with Pauli-Villars regularization

Abstract

The Pauli-Villars regularization scheme is often used for evaluating parton distributions within the framework of the chiral quark soliton model with the inclusion of the vacuum polarization effects. Its simplest version with a single subtraction term should, however, be taken with some caution, since it does not fully get rid of divergences contained in scalar and psuedoscalar quark densities appearing in the soliton equation of motion. To remedy this shortcoming, we propose here its natural extension, i.e., the Pauli-Villars regularization scheme with multisubtraction terms. We also carry out a comparative analysis of the Pauli-Villars regularization scheme and more popular proper-time one. It turns out that some isovector observables such as the isovector magnetic moment of the nucleon are rather sensitive to the choice of the regularization schemes. In the process of tracing the origin of this sensitivity, a noticeable difference of the two regularization schemes is revealed.