The expansion by regions in pi K scattering

Roland Kaiser (1, 2) , Julia Schweizer (3)

1 CPT - Centre de Physique Théorique - UMR 6207
2 CPT - Centre de Physique Théorique - UMR 7332
3 VIENNA U. - Institute for Theoretical Physics

We discuss a number of two loop (vertex) integrals relevant for pi K scattering at threshold. As such these are functions of two well separated mass scales, M_pi/M_K << 1. The method of regions allows an expansion in this mass ratio prior to the integration. In the cases considered, the coefficients in this expansion can be evaluated with elementary methods.

Mots clés: General properties of perturbation theory; Chiral symmetries; Perturbative calculations; Meson-meson interactions

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]

Roland Kaiser, Julia Schweizer. The expansion by regions in pi K scattering. 2006. ⟨hal-00021317v1⟩