Measurement of DD Decays from the psi(3770) Resonance

Abstract

We measure the production cross section of e^+ e^− → ψ(3770) → DD near the peak of the ψ(3770) resonance. The (69.80 ± 0.03) pb^{−1} of e^+ e^− annihilation data used were collected in 2010 over a center-of-mass energy range of 3.735 GeV to 3.870 GeV. From previously observed e^+ e^− → DD cross section measurements, this shape cannot be explained by a single Breit-Wigner. Instead, in this analysis we fitted the cross section by including interference effects from non-resonant DD production, and measured the mass and width of the ψ(3770) more precisely than previous results.