Georg Viehhauser

Abstract:

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we present new measurements of the branching fractions for D⁺→KSK⁺ and D⁺ → KSπ⁺. These results are combined with other CLEO measurements to extract the ratios of isospin amplitudes and phase shifts for D→KK and D→Kπ. © 1997 The American Physical Society.

Abstract:

Using the CLEO II detector at the Cornell Electron Storage Ring operated at [Formula presented] we have determined the Michel parameters ρ, ξ, and δ in [Formula presented] decay as well as the τ neutrino helicity parameter [Formula presented] in [Formula presented] decay. From a data sample of [Formula presented] produced τ pairs we analyzed events of the topologies [Formula presented] and [Formula presented] We obtain [Formula presented] [Formula presented] [Formula presented] and [Formula presented] where we have used the previously determined sign of [Formula presented] [ARGUS Collaboration, H. Albrecht et al., Z. Phys. C 58, 61 (1993); Phys. Lett. B 349, 576 (1995)]. We also present the Michel parameters as determined from the electron and muon samples separately. All results are in agreement with the standard model [Formula presented] interaction. © 1997 The American Physical Society.

Abstract:

The branching fractions for [Formula presented] [Formula presented] and [Formula presented] are measured using data collected with the CLEO detector at the CESR [Formula presented] collider: [Formula presented]=0.1776[Formula presented]0.0006[Formula presented]0.0017, [Formula presented]=0.1737[Formula presented]0.0008[Formula presented]0.0018, and [Formula presented]=0.1152[Formula presented]0.0005[Formula presented]0.0012, where the first error is statistical, the second systematic, and [Formula presented] refers to either a charged [Formula presented] or [Formula presented]. Also measured is the [Formula presented] mass, [Formula presented]=(1778.2[Formula presented]1.4) MeV. Lepton universality is affirmed by the relative branching fractions [Formula presented]/[Formula presented]=0.9777[Formula presented]0.0063[Formula presented]0.0087, [Formula presented]/[Formula presented]=0.6484[Formula presented]0.0041[Formula presented]0.0060) and the charged-current gauge coupling-constant ratios [Formula presented]=1.0026[Formula presented]0.0055, [Formula presented]=0.9990[Formula presented]0.0098). The [Formula presented] mass result may be recast as a [Formula presented] neutrino mass limit, [Formula presented]60 MeV at 95% C.L. © 1997 The American Physical Society.

Abstract:

Using data collected in the region of the γ\(4S\) resonance with the CLEO II detector operating at the Cornell Electron Storage Ring (CESR), we present the first observation of B mesons decaying into the charmed strange baryons Ξc⁰ and Ξc⁺. We find 79+/-27 Ξc⁰ and 125+/-28 Ξc⁺ candidates from B decays, leading to product branching fractions of B\(B^¯⤏c⁰X\)B\(c⁰⤏Ξ^-π⁺\) = \(0.144+/-0.048+/-0.021\)×10-3 and B\(B^¯⤏Ξ+cX\)B\(Ξ+C⤏Ξ^-π⁺π⁺\) = \(0.453+/-0.096+ 0.085- 0.065\)×10⁻³. © 1997 The American Physical Society.

Abstract:

We report new measurements of the differential and total branching ratios for inclusive [Formula presented] decay to [Formula presented], [Formula presented], and [Formula presented] and the first measurement of the same quantities for inclusive [Formula presented] decay to [Formula presented]. Here [Formula presented] is the mixture of [Formula presented] and [Formula presented] from [Formula presented] decay. Furthermore, since more than one charm particle (or antiparticle) of the same kind can be produced in [Formula presented] decay, here “inclusive [Formula presented] branching ratio” is used to mean the average number of charm particles and their antiparticles of a certain species produced in [Formula presented] decay. We obtain the following results (the first error is statistical, the second systematic of this analysis, the third propagated from other measurements): [Formula presented] [Formula presented] [Formula presented][Formula presented] [Formula presented] The following ratio of branching ratios is not affected by most of the systematic errors: [Formula presented][Formula presented] We also report the first measurement of the momentum-dependent [Formula presented] polarization and a new measurement of the [Formula presented] polarization in inclusive [Formula presented] decay. Using these measurements and other CLEO results and making some additional assumptions, we calculate the average number of [Formula presented] and [Formula presented] quarks produced in [Formula presented] decay to be [Formula presented]. © 1997 The American Physical Society.