Structure of the nucleon in chiral perturbation theory

Abstract

We discuss a renormalization scheme for relativistic baryon chiral perturbation theory which provides a simple and consistent power counting for renormalized diagrams. The method involves finite subtractions of dimensionally regularized diagrams beyond the standard modified minimal subtraction scheme of chiral perturbation theory to remove contributions violating the power counting. This is achieved by a suitable renormalization of the parameters of the most general effective Lagrangian. As applications we discuss the mass of the nucleon, the $\sigma$ term, and the scalar and electromagnetic form factors.Comment: Invited talk given by S. Scherer at the Fourth International Conference on Perspectives in Hadronic Physics, Trieste, Italy, 12 -16 May 2003, 8 pages, 7 figure