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

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.