Baryon chiral perturbation theory

Abstract

We provide a short introduction to the one-nucleon sector of chiral perturbation theory and address the issue of power counting and renormalization. We discuss the infrared regularization and the extended on-mass-shell scheme. Both allow for the inclusion of further degrees of freedom beyond pions and nucleons and the application to higher-loop calculations. As applications we consider the chiral expansion of the nucleon mass to order $\mathcal{O}(q^6)$ and the inclusion of vector and axial-vector mesons in the calculation of nucleon form factors. Finally, we address the complex-mass scheme for describing unstable particles in effective field theory.

Comments: 13 pages, 8 figures, invited talk given at the Third International Conference on Hadron Physics, TROIA'11, 22 - 25 August 2011, Canakkale, Turkey