Measurement of sigma(e^+e^- --> psi(3770) --> hadrons) at E_{cm}=3773 MeV

TL;DR

This paper reports a precise measurement of the cross section for e^+e^- annihilation into hadrons via the psi(3770) resonance at 3773 MeV, providing insights into its decay properties.

Contribution

The study presents the first high-precision measurement of the psi(3770) production cross section and its electronic width at a specific energy.

Findings

Measured cross section: (6.38+-0.08^{+0.41}_{-0.30}) nb

Difference between hadronic and D D-bar cross sections is negligible

Extracted electronic width: (0.204+-0.003^{+0.041}_{-0.027}) keV

Abstract

We measure the cross section for e^+e^- -> \psi(3770) -> hadrons at Ecm=3773 MeV to be (6.38+-0.08^{+0.41}_{-0.30}) nb using the CLEO detector at the CESR e^+e^- collider. The difference between this and the e^+e^- -> \psi(3770) -> DD-bar cross section at the same energy is found to be (-0.01+-0.08^{+0.41}_{-0.30}) nb. With the observed total cross section, we extract \Gamma_ee(\psi(3770))=(0.204+-0.003^{+0.041}_{-0.027}) keV. Uncertainties shown are statistical and systematic, respectively.