4 research outputs found

    B0 meson decays to rho0 K*0, f0 K*0, and rho-K*+, including higher K* resonances

    Get PDF
    We present branching fraction measurements for the decays B0 -> rho0 K*0, B0 -> f0 K*0, and B0 -> rho- K*+, where K* is an S-wave (K pi)_0* or a K*(892) meson; we also measure B0 -> f0 K_2*(1430)^0. For the K*(892) channels, we report measurements of longitudinal polarization fractions (for rho final states) and direct CP-violation asymmetries. These results are obtained from a sample of (471.0 +/- 2.8) x 10^6 BBbar pairs collected with the BaBar detector at the PEP-II asymmetric-energy e+ e- collider at the SLAC National Accelerator Laboratory. We observe rho0 K*(892)^0, rho0 (K pi)_0^{*0}, f0 K*(892)^0, and rho- K*(892)+ with greater than 5 sigma significance, including systematics. We report first evidence for f0 (K pi)_0^{*0} and f0 K_2*(1430)^0, and place an upper limit on rho- (K pi)_0^{*+}. Our results in the K*(892) channels are consistent with no direct CP-violation.Comment: 17 pages, 6 postscript figures, submitted to Phys. Rev.

    Search for CP violation in the decay τ^{-}→π^{-}K_{s}^{0}(≄Oπ^{0})Îœ_{τ}

    Get PDF
    We report a search for CP violation in the decay τ-→π-KS0(≄0π0)Μτ using a data set of 437×106 τ-lepton pairs, corresponding to an integrated luminosity of 476  fb-1, collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.36±0.23±0.11)% approximately 2.8 standard deviations from the standard model prediction of (0.36±0.01)%

    Amplitude analysis of B^{0}→K^{+}π^{-}π^{0} and evidence of direct CP violation in B→K*π decays

    Get PDF
    We analyze the decay B(0) -> K(+) pi(-) pi(0) with a sample of 4.54 x 10(8) B (B) over bar events collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the Dalitz plot. These results are combined with amplitudes measured in B(0) -> K(S)(0)pi(+)pi(-) decays to construct isospin amplitudes from B(0) -> K* pi and B(0) -> rho K decays. We measure the phase of the isospin amplitude Phi(3/2), useful in constraining the Cabibbo-Kobayashi-Maskawa unitarity triangle angle gamma and evaluate a CP rate asymmetry sum rule sensitive to the presence of new physics operators. We measure direct CP violation in B(0) -> K*(+) pi(-) decays at the level of 3 sigma when measurements from both B(0) -> K(+) pi(-) pi(0) and B(0) -> K(S)(0) pi(+) pi(-) decays are combined

    B0 meson decays to ρ0K∗0, f0K∗0, and ρ−K∗+, including higher K∗ resonances

    Get PDF
    We present branching fraction measurements for the decays B0→ρ0K*0, B0→f0K*0, and B0→ρ-K*+, where K* is an S-wave (Kπ)0* or a K*(892) meson; we also measure B0→f0K2*(1430)0. For the K*(892) channels, we report measurements of longitudinal polarization fractions (for ρ final states) and direct CP violation asymmetries. These results are obtained from a sample of (471.0±2.8)×106 BB̅ pairs collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the SLAC National Accelerator Laboratory. We observe ρ0K*(892)0, ρ0(Kπ)0*0, f0K*(892)0, and ρ-K*(892)+ with greater than 5σ significance, including systematics. We report first evidence for f0(Kπ)0*0 and f0K2*(1430)0, and place an upper limit on ρ-(Kπ)0*+. Our results in the K*(892) channels are consistent with no direct CP violation
    corecore