Abstract
We study the processes , and , with the photon radiated from the initial state. About 20 000, 33 000 and 4000 fully reconstructed events, respectively, have been selected from of BABAR data. The invariant mass of the hadronic final state defines the effective center-of-mass energy, so that these data can be compared with the corresponding direct measurements. From the , and mass spectra, the cross sections for the processes , and are measured for center-of-mass energies from production threshold to 4.5 GeV. The uncertainty in the cross section measurement is typically 6%–15%. We observe a structure at 1.9 GeV in both cross sections and a resonance structure with mass and width when the final state is extracted. We observe the in all these final states and measure the corresponding branching fractions.
23 More- Received 3 February 2006
DOI:https://doi.org/10.1103/PhysRevD.73.052003
©2006 American Physical Society