Structure of the Light Scalar Mesons from a Coupled Channel Analysis of the s-wave pi pi - k kbar Scattering

Abstract

The analysis of the poles of the $\pi \pi$ scattering amplitude is shown to favour a dynamical origin of the sigma meson: it is created by a strongly attractive $\pi \pi$ interaction in the $J^{PC}=0^{++}I=0$ channel. In the limit $N_c\to \infty$, the $\sigma$ meson disappears, contrary to the case of conventional $q\bar{q}$ states. Implications for the search of the scalar $q\bar{q}$ and glueball states are discussed.

Comments: 8 pages, 6 PostScript figures, Contribution to the Workshop on Hadron Spectroscopy, Frascati, March 8-12, 1999