相关论文: Measurement of the weak phase alpha from B0 --> a_…
Quasi two-body decays B^0(t)-> a_1^{+-}(1260) pi^{-+} identified by four charged pions determine a phase alpha_eff, which is equal to the weak phase alpha in the limit of vanishing penguin amplitudes. Applying flavor SU(3) to these decays…
We present improved measurements of the branching fractions and CP-asymmetries in the B0 --> pi+ pi-, B0 --> pi0 pi0, and B+ --> rho+ rho0 decays, which impact the determination of alpha. We find S(pi+ pi-) = -0.68 +/- 0.10 +/- 0.03 C(pi+…
We present a method for measuring the weak phase gamma using isospin analysis of three body B decays into K pi pi channels. Differential decay widths and time dependent asymmetry in B_d -> K_s pi^+pi^- mode needs to be measured into even…
From a time-dependent analysis of the decay $B^0_{d} \to \pi^+ \pi^-$ and using a model-dependent $A_P/A_T$ ratio of the penguin-to-tree amplitudes contributing to the decay, both the weak phase $\alpha$ and the strong phase shift…
In the absence of the QCD penguin contributions a measurement of the time-dependent asymmetry in the decay $B^0(t)\to \pi^+\pi^-$ gives directly the weak angle $\alpha$. Several bounds have been proposed in the literature on the magnitude…
The influence of strong and electroweak penguin amplitudes in $B/ \bar B \rightarrow \pi^+\pi^-$ is investigated in connection with the determination of the unitarity triangle angle $\alpha$ of the CKM matrix. A relation between the…
The BABAR collaboration measurements of the B -> pipi, B -> rhopi and B -> rhorho decays are presented. New results, from a 113 fb-1 data sample, on the time-dependent CP asymmetries of the longitudinally polarized component of the B0 ->…
A method is described which, under the assumption of SU(3) symmetry, allows one to determine the angle gamma=Arg(Vub^*) of the unitarity triangle from time-independent measurements of the branching ratios for the decays B^+ -> pi^0 K^+ and…
We report recent measurements of the CKM angle alpha using data collected by the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the SLAC National Accelerator Laboratory. In addition to improved constraints on alpha from the…
We report measurements of the branching fractions of neutral and charged B meson decays to final states containing a K_1(1270) or K_1(1400) meson and a charged pion. The data, collected with the BaBar detector at the SLAC National…
We present measurements of branching fractions in the b -> s s-bar s penguin-dominated decays B+ --> phi K+ and B0 --> phi K0 in a sample of approximately 89 million BBbar pairs collected by the BaBar detector at the PEP-II…
Using $471 \times 10^6 ~B \bar B$ decays recorded with the \babar\ detector at the PEP-II $e^+ e^-$ storage ring, we present the time-dependent \CP\ asymmetry measurement in the radiative penguin decay mode $B^0 \rightarrow K^0_S…
To observe CP-violating asymmetries through the interference of a weaker amplitude with a stronger one in $\bo \to D^{(*)} \pi$ and $\ob \to D^{(*)} \pi$ decays, one must collect enough events that the intensity associated with the weaker…
The extraction of the CKM angle $\alpha$ from the asymmetry in $B^0 \to \pi^+\pi^-$ vs ${\bar B^0} \to \pi^+\pi^-$ suffers from a currently unknown penguin contribution. Experimentally, one can determine the magnitude and phase of the CP…
We present a new measurement of the time-dependent CP asymmetry of B0->D*+D*- decays using (471+-5) million BBbar pairs collected with the BaBar detector at the PEP-II B Factory at the SLAC National Accelerator Laboratory. Using the…
Electromagnetic radiative penguin decays of the B meson were studied with the BaBar detector at SLAC's PEP-II asymmetric-energy B Factory. Branching fractions and isospin asymmetry of the decay B -> K* gamma, branching fractions of B ->…
The role of penguin amplitudes in CP violating $B$ decays is reviewed, emphasizing recent progress in the analysis of electroweak penguin contributions. It is shown how these terms are included in a model-independent manner when measuring…
We present a measurement of the branching fraction and time-dependent CP violation parameters in B0 --> a_1^+-(1260) pi^-+ decays. The results are obtained from the final data sample containing 772x10^6 BBbar pairs collected at the…
Using a data sample of 122 million Upsilon(4S) -> BBbar decays collected with BaBar detector at the PEP-II asymmetric B factory at SLAC, we measure the time-dependent-asymmetry parameters of the longitudinally polarized component in the B0…
Measurements of the time-dependent CP asymmetry in the decay $B^0_d (t) \to \pi^+ \pi^-$ and its charge conjugate by the BELLE and BABAR collaborations currently yield $C_{\pi \pi}^{+-} = -0.46 \pm 0.13$ and $S_{\pi \pi}^{+-} = -0.74 \pm…