相关论文: B-> rho pi, rho rho, pi pi: hunting for alpha
The hypothesis of the smallness of penguin contribution to charmless strangeless $B_d (\bar B_d)$ decays allows to determine with high accuracy the value of angle $\alpha$ from the currently available $B \to \rho\rho$, $B \to \pi\pi$ and…
The decay mode B -> rho pi is currently studied as a channel allowing, in principle, to measure without ambiguities the angle alpha of the unitarity triangle. It is also investigated by the CLEO Collaboration where a branching ratio larger…
The role of the decay mode B->rho pi for the determination of the unitarity angle alpha is critically examined in view of the smaller than expected ratio B(B->rho+/- pi-/+)/B(B->rho0 pi+/-) found by the CLEO collaboration.
We present recent measurements of the unitarity triangle angle phi2(alpha) using B -> pi pi, B -> rho rho, and B -> rho pi decays. The measurements are based on data samples collected with the Belle and BaBar detectors at the KEKB and…
The measurements of the angle alpha (phi2) of the unitarity triangle at the B factories are reviewed. The value of alpha determined by combining the results obtained in the B to pi pi, B to rho pi, and B to rho rho modes by both the BABAR…
The decays B_{d,s}^0 --> K^{(*)} K-bar^{(*)} can be used to measure the angle alpha of the CKM unitarity triangle. The theoretical error from SU(3) breaking is expected to be small, so that the determination of alpha is clean. Moreover,…
We reconsider two classical proposals for the determination of the angle gamma of the unitarity triangle: B^\pm => chi_{c0} \pi^\pm => \pi^+\pi^-\pi^\pm and B_s => rho^0 K_S => \pi^+ \pi^- K_S. We point out the relevance, in both cases, of…
We discuss new, theoretically clean strategies to determine the angle $\gamma$ of the unitarity triangle from $B_d\to DK_{S(L)}$, $B_s\to D\eta^{(')}, D\phi, ...$ decays, and point out that the $B_s\to DK_{S(L)}$ and $B_d\to D\pi^0,…
We show how B -> pi pi decays can be used to search for new physics in the b -> d flavour-changing neutral current. One needs one piece of theoretical input, which we take to be a prediction for P/T, the ratio of the penguin and tree…
Theoretical errors in the extraction of alpha from B -> pi^+ pi^-, rho^+ rho^-, rho pi decays are usually given in terms of upper bounds on alpha_eff-alpha obtained from isospin or from SU(3) relations, where alpha_eff is measured through…
Theoretically motivated smallness of the penguin amplitude in $B \to \pi \pi$ decays allowes to calculate the value of the unitarity triangle angle $\alpha (\phi_2)$ with good accuracy. The relatively large branching ratio of the decay into…
It has been pointed out by Gronau and Rosner that the angle gamma of the unitarity triangle could be determined by combining future results on B_s and B_d decays to K pi. Here we show that it is important to include in the analysis the…
After a brief look at the well-known standard approaches to determine the angle gamma of the unitarity triangle, we focus on two kinds of strategies, employing $B\to\pi K$ modes, and U-spin-related B decays. Interesting "puzzles", which may…
A method is proposed for the determination of the unitarity angle alpha through tree penguin interference. The modes needed would be of the form B0/B0-bar -> rho0 M and B0/B0-bar -> omega M where M is spin-0 uu-bar/dd-bar meson, for…
Defining a most economical parametrization of time-dependent B-> rho^\pm pi^\mp decays, including a measurable phase alpha_{eff} which equals the weak phase alpha in the limit of vanishing penguin amplitudes, we propose two ways for…
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 review recent results of the BABAR and BELLE Collaborations on the the alpha and gamma angles of the unitary triangle, on the B to K pi pi Dalitz-plot analyses, and on the searches for baryonic B decays and for B to DD decays.
We present results from an analysis of B0 to rho+rho- decays using 383.6 million BB-bar pairs collected by the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. The measurements of the B0 to rho+rho- branching fraction,…
An improved flavor SU(3) method is presented for determining the weak angle $\gamma$ of the unitarity triangle using decay rates for $B^+\to K\pi, B^+\to K^+\bar K^0$ and $B^+\to \pi^+\eta$ (or $B^0\to K\pi$ and $B_s\to K \pi$), their…
The potential of constraints on the angle alpha of the Unitarity Triangle from studies of B0 -> pi+ pi- pi0 decays is reviewed. The experimental inputs needed for an isospin analysis are starting to become available. The precision of…