Measurements of the cross sections for e+e-→hadrons at 3.650, 3.6648, 3.773 GeV and the branching fraction for ψ (3770)→non-D(D)over-bar

Using the BES-II detector at the BEPC Collider, we measured the lowest order cross sections and the R values (R = sigma(0)(e+e--> hadrons)/sigma(0)(e+e-->mu+mu-)) for inclusive hadronic event production at the centre-of-mass energies of 3.650, 3.6648 and 3.773 GeV. The results lead to R-uds = 2.218 +/- 0.019 +/- 0.089 which is the average of these measured at 3.650 GeV and 3.6648 GeV, and R = 3.746 +/- 0.037 +/- 0.187 at root s = 3.773 GeV. We determined the lowest order cross section for psi (3770) production to be sigma(B)(psi)((3770)) = (9.323 +/- 0.253 +/- 0.801) nb at 3.773 GeV, the branching fractions for psi (3770) decays to be BF(psi (3770) -> D-0(D) over bar (0)) = (49.5 +/- 1.3 +/- 3.8)%, BF(psi (3770) -> D+D-) = (35.7 +/- 1.1 +/- 3.4)% and BF(psi (3770) -> D (D) over bar) = (85.5 +/- 1.7 +/- 5.8)%, which result in the total non-D (D) over bar branching fraction of psi(3770) decay to be BF(psi (3770) -> non-D (D) over bar) = (14.5 +/- 1.7 +/- 5.8)%. (c) 2006 Elsevier B.V. All rights reserved.