INFN - Laboratori Nazionali di Frascati, May 1995

From: The Second DAFNE Physics Handbook

Chapter 10: Two Photon Initiated Processes

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.

Low-energy photon-photon collisions
in chiral perturbation theory

S. Bellucci, J. Gasser and M.E. Sainio

INFN-Laboratori Nazionali di Frascati, P.O.Box 13, I-00044 Frascati, Italy

Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5,
CH-3012 Bern, Switzerland

Dept. of Theoretical Physics, University of Helsinki, P.O. Box 9 (Siltavuorenpenger 20 C), FIN-00014 Helsinki, Finland

We discuss aspects of the processes

in the framework of chiral perturbation theory (CHPT).

• 1 Introduction
• 2 Notation
• 3 Low-energy expansion
• 4 The cross section
• 5 The cross section
• 6 Pion polarizabilities
  • 6.1 Data on pion polarizabilities
  • 6.2 Chiral expansion of and
  • On the determination of polarizabilities from data on
• 7 Improvements at DANE
• References