Scalar mesons as simple quark+antiquark states

TL;DR

This paper revisits the Nijmegen Unitarized Meson Model, demonstrating that scalar mesons up to 1.5 GeV can be described as quark-antiquark states coupled to meson channels, explaining resonance doubling and scattering without parameter fitting.

Contribution

It shows that scalar mesons can be modeled as quark-antiquark states with flavor-symmetric couplings, capturing resonance phenomena and scattering behavior without fitting parameters.

Findings

Scalar states up to 1.5 GeV are described as quark-antiquark states.

Resonance doubling is explained by strong S-wave decay.

S-wave meson-meson scattering is well described without parameter fit.

Abstract

The Nijmegen Unitarized Meson Model and its application to scalar mesons is briefly revisited. It is shown that all scalar states up to 1.5 GeV can be described as triplet-P-zero quark+antiquark states coupled to the OZI-allowed open and closed two-meson channels consisting of pseudoscalar and vector mesons. Crucial are the manifestation of a resonance-doubling phenomenon, typical for strong S-wave decay, and the employment of truly flavor-symmetric coupling constants. Also S-wave meson-meson scattering is thus reasonably well described, without any parameter fit.