Georg Viehhauser

Abstract:

We have measured the branching fractions for B → D®X, B → D®X, and B → D®Xℓ+v. From these results and some previously measured branching fractions, we obtain B(b → cc®s) = (21.9 ± 3.7)%, B(b → sg) < 6.8% at 90% C.L., and B(D0 → K− π+ = (3.69 ± 0.20)%. Implications for the “B semileptonic decay problem” (measured branching fraction being below theoretical expectations) are discussed. With the increase in the value of B(b → cc®s) due to B → DX, the discrepancy is no longer statistically compelling. © 1998 American Physical Society.

Abstract:

The CLEO II detector at the e+e− storage ring CESR has been used to search for two-photon production of the fJ(2220) decaying into π+π−. No evidence for a signal is found in 4.77fb−1 of data and a 95% C.L. upper limit on [τγγBπ+π−]fJ(2220) of 2.5 eV is set. If this result is combined with the BES Collaboration's measurement of fJ(2220)→π+π− in radiative J/Ψ decay and the recent CLEO result for [τγγBK0SK0S]fJ(2220), a 95% C.L. lower limit on the stickiness of 102 is obtained. This result for the stickiness provides further support for a substantial neutral parton content in the fJ(2220). © 1998 The American Physical Society.

Abstract:

We have studied semileptonic B meson decays with a p-wave charm meson in the final state using 3.29×10⁶BB^¯ events collected with the CLEO II detector at the Cornell Electron-Positron Storage Ring.We find a value for the exclusive semileptonic product branching fraction B(B⁻→D1⁰ℓ⁻ν^¯ℓ)B(D1⁰→D*+π⁻) = (0.373±0.085±0.052±0.024)% and an upper limit for B(B⁻→D2^*0ℓ-ν^¯ℓ)B(D2^*0→D*+π⁻)<0.16% (90% C.L.).Furthermore, we present the first measurement of the q² spectrum for B⁻→D1⁰ℓ⁻ν^¯ℓ. © 1998 The American Physical Society.

Abstract:

Using a data sample with an integrated luminosity of 3.9 fb^-1 collected in e⁺e^- annihilation with the CLEO-II detector at the Cornell Electron Storage Ring, we have measured the branching ratios for the decay modes Ds⁺→(η,η′)π⁺ and Ds⁺→(η,η′)ρ⁺ relative to Ds⁺→φ⁺. These decay modes are among the most common hadronic decays of the Ds⁺ , and can be related by factorization to the semileptonic decays Ds⁺ →(η,η′)ℓ⁺νl. The results obtained are compared with previous CLEO results and with the branching ratios measured for the related semileptonic decays. We also report results on the Cabibbo-suppressed decays of the D⁺ to the same final states. © 1998 The American Physical Society.

Abstract:

Using data recorded by the CLEO-II detector at CESR, we report new measurements of the branching fractions for the decays of the charmed baryon Λc+ into pK-π+π0, pK0, pK0π+π-, and pK0π0, all measured relative to pK-π+. The relative branching fractions are 0.67±0.04±0.11,0.46±0.02±0.04,0.52±0.04±0.05, and 0.66±0.05±0.07, respectively. © 1998 The American Physical Society.