Chiral Perturbation Theory with Photons and Leptons

Abstract

I discuss a low-energy effective field theory which permits the full treatment of isospin-breaking effects in semileptonic weak interactions. In addition to the pseudoscalars and the photon, also the light leptons have to be included as dynamical degrees of freedom in an appropriate chiral Lagrangian. I describe the construction of the local action at next-to-leading order.

Comments: 6pages, Latex, Talk given at the 8th International Symposium on Meson-Nucleon Physics and the Structure of the Nucleon, Zuoz, Switzerland, August 15-21, 1999