INFN - Laboratori Nazionali di Frascati, May 1995

From: The Second DAFNE Physics Handbook

Chapter 4: Other Approaches to Low Energy Dynamics

Eds. L. Maiani, G. Pancheri, N. Paver

Supported by the INFN, by the EC under the HCM contract number CHRX-CT920026 and by the authors home institutions.

Generalized Chiral Perturbation Theory

M. Knecht and J. Stern

Division de Physique Théorique , Institut de Physique Nucléaire
F-91406 Orsay Cedex, France

Abstract:

The Generalized Chiral Perturbation Theory enlarges the framework of the standard PT, relaxing certain assumptions which do not necessarily follow from QCD or from experiment, and which are crucial for the usual formulation of the low energy expansion. In this way, the experimental tests of the foundations of the standard PT become possible. Emphasize is put on physical aspects rather than on formal developements of GPT

• 1 Introduction
• 2 Expansion of Goldstone Boson masses
• 3 Expansion of the effective Lagrangian
• 4 Examples of differences between standard and generalized PT
• 5 Values of the low energy constants
• 6 Experimental tests
• References