NUCLEON PARTON DISTRIBUTIONS AT LOW NORMALIZATION POINT IN THE LARGE N-C LIMIT

At large N-c the nucleon can be viewed as a soliton of the effective c hiral lagrangian. This picture of nucleons allows for a consistent non -perturbative calculation of the leading-twist parton distributions at a low normalization point. We derive general formulae for the polariz ed and unpolarized distributions (singlet and non-singlet) in the chir al quark-soliton model. The consistency of our approach is demonstrate d by checking the baryon number, isospin and total momentum sum rules, as well as the Bjorken sum rule. We present numerical estimates of th e quark and antiquark distributions and find reasonable agreement with parameterizations of the data at a low normalization point. In partic ular, we obtain a sizeable fraction of antiquarks, in agreement with t he phenomenological analysis.