Reconciling the Light Scalar Mesons with Breit-Wigner Resonances as well as the Quark Model

Abstract

Resonances appearing in hadronic scattering processes are described by a two-phase model. In the one phase, scattering products are observed, whereas the other phase describes confinement. A so-called ``Resonance-Spectrum Expansion'' is derived, containing expressions that resemble Breit-Wigner formulae. This method also provides a straightforward explanation for the origin of the light scalar mesons without requiring extra degrees of freedom.

Comments: LaTeX, 30 pages + 2 figures