Light Scalar Mesons $\sigma(500)$, $f_0(980)$ and $\kappa$ in Charm Meson Decays

TL;DR

This paper analyzes charm meson decays to study light scalar mesons, providing evidence and measurements for the $\sigma(500)$, $_0(980)$, and $\kappa$ mesons, highlighting charm decays as a new tool in light meson research.

Contribution

It presents new experimental evidence and measurements of light scalar mesons in charm decays, expanding the understanding of these mesons in a novel decay environment.

Findings

Evidence for the $\kappa$ meson with measured mass and width.

Strong evidence for the $\sigma(500)$ meson with measured parameters.

Results on the $_0(980)$ parameters from charm decay data.

Abstract

We present recent results on scalar light mesons based on Dalitz plot analyses of charm decays from Fermilab experiment E791. Scalar mesons are found to have large contributions to the decays studied, $D^+\to K^-\pi^+\pi^+$ and $D^+, D_s^+\to\pi^-\pi^+\pi^+$. From the first decay, we find good evidence for the existence of the light and broad $\kappa$ meson and we measure its mass and width. We find strong evidence for the $\sigma(500)$ meson from $D^+\to\pi^-\pi^+\pi^+$ decay and measure its mass and width. We also present the results obtained for the $f_0(980)$ parameters through the $D^+_s \to\pi^-\pi^+\pi^+$ decay. These results demonstrate the importance of charm decays as a new environment for the study of light meson physics.