Georg Viehhauser

Abstract:

We have searched for lepton flavor violating decays of the τ lepton using final states with an electron or a muon and one or two π0 or η mesons but no neutrinos. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 4.68 fb−1. No evidence for signals was found, resulting in much improved limits on the branching fractions for the one-meson modes and the first upper limits for the two-meson modes. © 1997 The American Physical Society.

Abstract:

We have searched for the decay of the [Formula presented] lepton into seven charged particles and zero or one [Formula presented]. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 4.61 [Formula presented]. No evidence for a signal is found. Assuming all the charged particles are pions, we set an upper limit on the branching fraction [Formula presented] at the 90% confidence level. This limit represents a significant improvement over the previous limit. © 1997 The American Physical Society.

Abstract:

Using the CLEO-II data set we have searched for the decays B0→D(*)+D(*)-. We observe one candidate signal event for the decay B0→D*+D*- with an expected background of 0.022±0.011 events. This yield corresponds to a branching fraction of B(B0→D*+D*-)=[5.3+7.1-3.7(stat)±1.0(syst)]×10-4 and an upper limit of B(B0→D*+D*-)<2.2×10-3 at the 90% C.L. We see no significant excess of signal above the expected background level in the other modes, and we calculate the 90% C.L. upper limits on the branching fractions to be B(B0→D*±D*∓)<1.8×10-3 and B(B0→D+D-)<1.2×10-3. © 1997 The American Physical Society.

Abstract:

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we determine the ratio [Formula presented] for the mean charged multiplicity observed in [Formula presented] events, [Formula presented], to the mean charged multiplicity observed in [Formula presented] events, [Formula presented]. We find [Formula presented] [Formula presented] for jet-jet masses less than 7 GeV. © 1997 The American Physical Society.

Abstract:

We use the CLEO detector at the Cornell e+e− storage ring, CESR, to search for the two-photon production of the glueball candidate fj(2220) in its decay to K8K8. We present a restrictive upper limit on the product of the two-photon partial width and the K8K8 branching fraction, (γγγBK8K8)fj(2220). We use this limit to calculate a lower limit on the stickiness, which is a measure of the two-gluon coupling relative to the two-photon coupling. This limit on stickiness indicates that the fj(2220) has substantial glueball content. © 1997 The American Physical Society.