1. Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany;2. II. Institut für Experimentalphysik der Universität Hamburg, Germany;3. Physikalisches Institut der Universität Heidelberg, Germany
Abstract:
A search for narrow resonances in e+e? annihilation at c.m. energies between 29.90 and 31.46 GeV provides no evidence for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is 38 nb MeV, significantly below the value expected for the lowest (t,t?) bound state.