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.
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We present measurements of CP-violating asymmetries in the decay B0 -> a_1(1260)^{+-} pi^{-+} with a_1(1260)^{+-} -> pi^{-+} pi^{+-} pi^{+-}. The data sample corresponds to 384 million B B-bar pairs ...collected with the BaBar detector at the PEP-II asymmetric B-factory at SLAC. We measure the CP-violating asymmetry A^{a_1 \pi}_{CP}=-0.07+-0.07+-0.02, the mixing-induced CP violation parameter S_{a_1 \pi}= 0.37 +-0.21+-0.07, the direct CP violation parameter C_{a_1 \pi}=-0.10+-0.15+-0.09, and the parameters \Delta C_{a_1 \pi}=0.26+-0.15+-0.07 and \Delta S_{a_1\pi}=-0.14+-0.21+-0.06. From these measured quantities we determine the angle \alpha_{\rm eff}= 78.6^{\circ} +- 7.3^{\circ}.
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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.
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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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We present updated measurements of time-dependent CP asymmetries in fully-reconstructed neutral B decays to several CP eigenstates containing a charmonium meson. The measurements use a data sample of ...(383 +/- 4) x 10^6 Y(4S)-> BBbar decays collected with the BABAR detector at the PEP-II B factory. We determine sin2beta = 0.714 +/- 0.032 (stat) +/- 0.018 (syst) and |lambda| = 0.952 +/- 0.022 (stat) +/- 0.017 (syst).
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A search for lepton flavor violating decays of the $\tau$ lepton to a lighter mass lepton and a pseudoscalar meson has been performed using 339 fb$^{-1}$ of $e^+e^-$ annihilation data collected at a ...center-of-mass energy near 10.58 GeV by the BaBar detector at the SLAC PEP-II storage ring. No evidence of signal has been found, and upper limits on the branching fractions are set at $10^{-7}$ level.
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We present updated measurements of \CP-violating asymmetries in the decays $\Bz\to\Dstarpm\Dmp$ and $\Bz\to\Dp\Dm$ using $(383\pm 4) \times 10^{6} \BB$ pairs collected by the \babar detector at the ...PEP-II $B$ factory. We determine the time-integrated \CP asymmetry ${\mathcal{A}}_{\Dstarpm\Dmp}=0.12\pm 0.06\pm 0.02$, and the time-dependent asymmetry parameters to be $C_{\Dstarp\Dm} =0.18\pm 0.15\pm 0.04$, $S_{\Dstarp\Dm}=-0.79\pm 0.21\pm 0.06$, $C_{\Dstarm\Dp} =0.23\pm 0.15\pm 0.04$, $S_{\Dstarm\Dp} =-0.44\pm 0.22\pm 0.06$, $C_{\Dp\Dm} =0.11\pm 0.22\pm 0.07$, and $S_{\Dp\Dm} =-0.54\pm 0.34\pm 0.06$, where the first uncertainty is statistical and the second is systematic.
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We perform an amplitude analysis of B+- -> phi(1020) K*(892)+- decay with a sample of about 384 million BBbar pairs recorded with the BABAR detector. Overall, twelve parameters are measured, ...including the fractions of longitudinal f_L and parity-odd transverse f_perp amplitudes, branching fraction, strong phases, and six parameters sensitive to CP-violation. We use the dependence on the Kpi invariant mass of the interference between the JP=1- and 0+ Kpi components to resolve the discrete ambiguity in the determination of the strong and weak phases. Our measurements of f_L=0.49+-0.05+-0.03, f_perp=0.21+-0.05+-0.02, and the strong phases point to the presence of a substantial helicity-plus amplitude from a presently unknown source.
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We present evidence for D0-anti-D0 mixing in D0 --> K+pi- decays from 384 fb^{-1} of e+e- colliding-beam data recorded near sqrt(s) 10.6 GeV with the BaBar detector at the PEP-II storage rings at ...SLAC. We find the mixing parameters x'^2 = -0.22 +- 0.30 (stat.) +- 0.21 (syst.) x 10^{-3} and y' = 9.7 +- 4.4 (stat.) +- 3.1 (syst.) x 10^{-3}, and a correlation between them of -0.94. This result is inconsistent with the no-mixing hypothesis with a significance of 3.9 standard deviations. We measure R_D, the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates, to be 0.303 +- 0.016 (stat.) +- 0.010 (syst.)%. We find no evidence for \CP violation.
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The Beijing Spectrometer (BESIII) collaboration uses \(e^+e^-\) collisions in the tau-charm energy region to study a broad spectrum of topics. These include studies of light mesons and light baryons, ...studies of charmonium, including exotic mesons and baryons containing charmonium, studies of charmed mesons and baryons, studies of QCD and tau physics, as well as searches for new physics. The following is a Snowmass white paper that outlines the BESIII accomplishments and potential in each of these areas.
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