Using 226 million $B\bar{B}$ events recorded on the $\Upsilon(4S)$ resonance with the BABAR detector at the SLAC $e^+e^-$ PEPII storage rings, we reconstruct $B^- \to D^{*0} e^-\bar{\nu}_e$ decays ...using the decay chain $D^{*0} \to D^0\pi^0$ and $D^0 \to K^-\pi^+$. From the $w$ dependence of their differential rate, and using the form factor description by Caprini et al., we obtain the results $\rho_{A_1}^2 = 1.16\pm 0.06 \pm 0.08$, $F(1)\cdot|V_{cb}| =(35.9\pm 0.6 \pm 1.4)\cdot 10^{-3}$, and ${\cal{B}}(B^- \to D^{*0}e^-\bar{\nu}_e) = (5.56\pm 0.08\pm 0.41)%$.
We present measurements of the branching fraction and time-dependent CP asymmetries in B0->J/Psi pi0 decays based on 466 million Y(4S)->BBbar events collected with the BaBar detector at the SLAC ...PEP-II asymmetric-energy B factory. We measure the CP asymmetry parameters S=-1.23 +/- 0.21 +/- 0.04 and C=-0.20 +/- 0.19 +/- 0.03, where the measured value of S is 4.0 standard deviations from zero including systematic uncertainties. The branching fraction is determined to be B(B0->J/Psi pi0)=(1.69 +/- 0.14 +/- 0.07)*10^{-5}.
We present the results of searches for B decays to charmless final states involving phi, fzero(980), and charged or neutral rho mesons. The data sample corresponds to 384 million BBbar pairs ...collected with the babar detector operating at the PEP-II asymmetric-energy epem collider at SLAC. We find no significant signals and determine the following 90% confidence level upper limits on the branching fractions, including systematic uncertainties: B(B0->phiphi) < 2.0 x 10^-7, B(B+->phirho+) < 30 x 10^-7, B(B0->phirho0) < 3.3 x 10^-7, B(B0-phif0) x B(f0->pi+pi-) < 3.8 x 10^-7, and B(B0->f0f0) x B(f0->pi+pi-) x B(f0->K+K-) < 2.3 x 10^-7
BaBar silicon vertex tracker: Status and prospects Re, V.; Bondioli, M.; Bruinsma, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2006, Volume:
569, Issue:
1
Journal Article
We present a search for the lepton flavor violating decay B+ --> K+ tau-/+ mu+/- using 383 million B Bbar events collected by the BABAR experiment. The branching fraction for this decay can be ...substantially enhanced in new physics models. The kinematics of the tau from the signal B decay are inferred from the K+, mu, and other B in the event, which is fully reconstructed in one of a variety of hadronic decay modes, allowing the signal B candidate to be fully reconstructed. We observe no excess of events over the expected background and set a limit of B(B+ --> K+ tau mu) < 7.7 x 10^-5 at 90% confidence level, where the branching fraction is for the sum of the K+ tau- mu+ and K+ tau+ mu- final states.
We analyze the decay B0 --> K+ K- K0 using 383 million B-Bbar events collected by the BaBar detector at SLAC to extract CP violation parameter values over the Dalitz plot. Combining all K+ K- K0 ...events, we find A_CP = -0.015 +/- 0.077 +/- 0.053 and beta_eff = 0.352 +/- 0.076 +/- 0.026 rad, corresponding to a CP violation significance of 4.8 sigma. A second solution near pi/2 - beta_eff is disfavored with a significance of 4.5 sigma. We also report A_CP and beta_eff separately for decays to phi(1020) K0, f0(980) K0, and K+ K- K0 with m_{K+ K-} > 1.1 GeV/c^2.
A search for the neutrinoless, lepton-flavor violating decay of the tau lepton into three charged leptons has been performed using 376 fb^{-1} of data collected at an e^+e^- center-of-mass energy ...around 10.58 GeV with the BaBar detector at the PEP-II storage rings. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (4-8) x 10^{-8} at 90% confidence level.
We report the results of a CP violation analysis of the decay B+/- --> D(pipipi0)K+/-, where D(pipipi0) indicates a neutral D meson detected in the final state pi+pi-pi0, excluding K_S pi0. The ...analysis makes use of 324 million e+e- --> BB events recorded by the BaBar experiment at the PEP-II e+e- storage ring. By analyzing the pi+pi-pi0 Dalitz plot distribution and the B+/- --> D(pipipi0)K+/- branching fraction and decay rate asymmetry, we calculate parameters related to the phase gamma of the CKM unitarity triangle. We also measure the magnitudes and phases of the components of the D0 --> pi+pi-pi0 decay amplitude.
We present measurements of the branching fractions for the decays B+/- --> a1(1260)+/- pi0 and B+/- --> a1(1260)0 pi+/- from a data sample of 232 * 10^6 BB pairs produced in e+e- annihilation through ...the Y(4S) resonance. We measure the branching fraction B(B+/- --> a1(1260)+/- pi0) * B(a1(1260)+/- --> pi- pi+ pi+/-) = (13.2 +/- 2.7 +/- 2.1) * 10^-6 with a significance of 4.2 sigma, and the branching fraction B(B+/- --> a1(1260)0 pi+/-) * B(a1(1260)0 --> pi- pi+ pi0) = (20.4 +/- 4.7 +/- 3.4) * 10^-6 with a significance of 3.8 sigma, where the first error quoted is statistical and the second is systematic.
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