Measurement of branching fractions and charge asymmetries for exclusive B decays to charmonium
Physical Review Letters 94:14 (2005)
Abstract:
We report measurements of branching fractions and charge asymmetries of exclusive decays of neutral and charged B mesons into two-body final states containing a charmonium state and a light strange meson. The charmonium mesons considered are J/ψ, ψ(2S) and χc1, and the light meson is either K or K*. We use a sample of about 124 × 106 BB̄ pairs collected with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center. © 2005 The American Physical Society.Limit on the B0→ρ0ρ0 branching fraction and implications for the Cabibbo-Kobayashi-Maskawa Angle α
Physical Review Letters 94:13 (2005)
Abstract:
We search for the decay B0 → ρ0ρ 0 in a data sample of about 227 × 106 Γ(4S) → B B̄ decays collected with the BABAR detector at the PEP-II asymmetric-energy e+ e- collider at SLAC. We find no significant signal and set an upper limit of 1.1 × 10-6 at 90% C.L. on the branching fraction. As a result, the uncertainty due to penguin contributions on the Cabibbo-Kobayashi-Maskawa unitarity angle α measured in B → ρρ decays is decreased to 11° at 68% C.L. © 2005 The American Physical Society.Study of the B- → J/ΨK -π+π- decay and measurement of the B - → X(3872)K- branching fraction
Physical Review D - Particles, Fields, Gravitation and Cosmology 71:7 (2005) 1-7
Abstract:
We study the decay B- → J/ΨK -π+π- using 117×106 BB̄ events collected at the Y(4S) resonance with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring. We measure the branching fractions ℬ (B- → J/ΨK -π+π-) = (116±7(stat.) ±9(syst.))×10-5 and ℬ (B- → X(3872)K-) × ℬ (X(3872) → J/Ψπ+π -) = (1.28±0.41)×10-5 and find the mass of the X(3872) to be 3873.4±1.4 MeV/c2. We search for the h c narrow state in the decay B- → hcK -, hc → J/Ψπ+π- and for the decay B- → J/ΨD0π-, with D0 → K-π+. We set the 90% C.L. limits ℬ(B- → hcK-) × ℬ(h c → J/Ψπ+π-)<3. 4×10-6 and ℬ(B- → J/ΨD 0π-)<5.2×10-5. © 2005 The American Physical Society.Search for the decay B+ → K+ νν̄
Physical Review Letters 94:10 (2005)
Abstract:
We search for the rare flavor-changing neutral-current decay B+ → K+ νν̄ in a data sample of 82 fb-1 collected with the BABAR detector at the PEP-II S-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-B decay. Using these two independent samples we obtain a combined limit of ℬ(B+ →K+ νν̄) ≤ 5.2 × 10-5 at the 90% confidence level In addition, by selecting for pions rather than kaons, we obtain a limit of ℬ(B+ → π+ νν̄) < 1.0 × 10-4 using only the hadronic B reconstruction method. © 2005 The American Physical Society.Measurement of the B̄0 → D *+ℓ-ν̄ℓ decay rate and
Physical Review D - Particles, Fields, Gravitation and Cosmology 71:5 (2005) 1-8