Light Meson Physics from Charm Decays at Fermilab E791

Abstract

Abstract. We present recent results on 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,From the Kππ final state, we find good evidence for the existence of the light and broad κ meson and we measure its mass and width. We also discuss recently published results on the 3π final states, especially the measurement of the f 0 parameters and the evidence for the σ meson from D + → σπ + . These results demonstrate the importance of charm decays as a new environment for the study of light meson physics.

S-wave andP-wave ππ andKπ contributions to three-body decay processes in the Resonance- Spectrum Expansion

“…In Refs. [14,15] there are similar conclusions with respect to the data of E791 [12], LASS [16] and BESII [17]. It is very fortunate that such data exist nowadays.…”

The light scalar mesons within quark models

“…[27]. The physical pole in Kπ isodoublet S-wave scattering, related to experiment [37,36], comes out at 727 − i263 MeV in Ref. [7].…”

“…However, some structures in the scattering cross section stem from the cavity which is formed by quark exchange or pair creation [27]. The most notable of such states are the low-lying resonances observed in S-wave pseudoscalar-pseudoscalar scattering [35,36,37,38].…”