Abstract

We developed a manifestly Lorentz covariant chiral quark model for the study of baryons as bound states of constituent quarks in an extension of our previous approach. The investigations are related to the ongoing and planned experiments on improved measurements of the elastic baryon form factors and their decay characteristics. The approach is based on a non-linear chirally symmetric Lagrangian, which involves effective degrees of freedom-constituent quarks and the chiral (meson) fields. In a first step, this Lagrangian can be used to perform a dressing of the constituent quarks by a cloud of light pseudoscalar mesons and other heavy states using the calculational technique developed by Becher and Leutwyler. We calculate the dressed transition operators with a proper chiral expansion which are relevant for the interaction of quarks with external fields in the presence of a virtual meson cloud. These operators are used in the calculation of baryon matrix elements. (c) 2005 Elsevier B.V. All rights reserved.