Eur. Phys. J. C (2002) 23: 707-718
https://doi.org/10.1007/s100520200902

Theoretical physics

Isospin breaking in low-energy charged pion–kaon elastic scattering

Centre de Physique Théorique, CNRS-Luminy, case 907, 13288, Marseille Cedex 09, France

^* e-mail: nehme@cpt.univ-mrs.fr

Received: 19 November 2001
Revised: 21 December 2001
Published online: 5 April 2002

Abstract

We use chiral perturbation theory to evaluate the scattering amplitude for the process at leading and next-to-leading orders in the chiral counting and in the presence of isospin breaking effects. We also discuss the influence of the latter on the combination of the -wave scattering lengths which is relevant for the 2S–2P energy level shift of atoms.