First observation of the decays B0 → D*- p̄π+ and B0 → D*-pn̄
Physical Review Letters 86:13 (2001) 2732-2736
Abstract:
Decay modes of the B0 of the type B → DNN̄X were observed. Measurements imply that DNN̄X final states may contribute substantially to the total observed B → barvon rate. Branching fractions were accurately measured.Measurement of the relative branching fraction of upsilon(4S) to charged and neutral B-meson pairs.
Phys Rev Lett 86:13 (2001) 2737-2741
Abstract:
We analyze 9.7x10(6) B_B pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Upsilon(4S) resonance. We measure the rates for B0-->J/psiK((*)0) and B+-->J/psiK((*)+) decays and use the world-average B-meson lifetime ratio to extract the relative widths f(+-) / f(00) = gamma(Upsilon(4S)-->B+B-) / gamma(Upsilon(4S)-->B0 B-0)) = 1.04+/-0.07(stat)+/-0.04(syst). With the assumption that f(+-)+f(00) = 1, we obtain f(00) = 0.49+/-0.02(stat)+/-0.01(syst) and f(+-) = 0.51+/-0.02(stat)+/-0.01(syst). This production ratio and its uncertainty apply to all exclusive B-meson branching fractions measured at the Upsilon(4S) resonance.Measurement of the lambda(+)(c) lifetime.
Phys Rev Lett 86:11 (2001) 2232-2236
Abstract:
The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties.Measurement of the Λc + lifetime
Physical Review Letters 86:11 (2001) 2232-2236
Abstract:
The lifetime of the lowest-mass charm bryon is measured to provide a window for the nonperturbative sector of heavy quark decay. The data are obtained in a colliding beam environment in the CLEO II.V detector at the Cornell Electron Storage Ring. In this environment, the event topologies and backgrounds are very different from those encountered in high energy fixed-target experiments.First observation of the sigma(*+)(c) baryon and a new measurement of the sigma(*+)(c) mass.
Phys Rev Lett 86:7 (2001) 1167-1170