Related papers: Weak phase alpha from B^0-> a_1^{+-}(1260) pi^{-+}
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…
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 suggest two methods (based on flavor SU(3) symmetry) to determine the CKM angle $\gamma$ using the decays $B_d$, $B^+ \to K \eta (\eta')$ and $B_s \to \pi \eta (\eta')$, respectively. Rescattering effects are partly included -- we…
We discuss implications of recent experimental data for B decays into two pseudoscalar mesons, with emphasis on those with $\eta$ and $\eta'$ in the final states. Applying a U-spin argument, we show that tree and penguin amplitudes, both in…
Electroweak penguin (EWP) amplitudes are studied model-independently in $B$ meson decays to charmless final states consisting of a vector meson ($V$) and a pseudoscalar meson ($P$). A set of SU(3) relations is derived between EWP…
Penguin contributions, being not negligible in general, can hide the information on the CKM angle alpha coming from the measurement of the time-dependent B0(t) -> pi+pi- CP-asymmetry. Nevertheless, we show that this information can be…
We present a method to measure the CKM phase $\alpha$ and the tree and penguin (strong and electroweak) amplitudes in $B \rightarrow \pi \pi$ decays, based on isospin consideration and the weak assumption that all tree amplitudes have a…
Isospin and flavor SU(3) set stringent bounds on penguin pollution in $B^0(t)\to \rho^+\rho^-$, providing a theoretically precise determination of $\alpha\equiv \phi_2 $, $\alpha = (91\pm 7_{\rm exp}\pm 3_{\rm th})^\circ$. Isospin breaking…
The decays of $B$ mesons to a pair of charmless pseudoscalar ($P$) mesons are analyzed within a framework of flavor SU(3). Symmetry breaking is taken into account in tree ($T$) amplitudes through ratios of decay constants; exact SU(3) is…
Phases of elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be obtained using decays of $B$ mesons to $\pi^+ \pi^-$, $\pi^\pm K^\mp$, and $\pi^+ K^0$ or $\pi^- \overline{K}^0$. For $B^0~{\rm or}~ \overline{B}^0 \to \pi^+ \pi^-$,…
Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…
A new way of determining the phases of weak amplitudes in charged $B$ decays based on SU(3) symmetry is proposed. The CP violating phase $\gamma$ can now be determined without the previous difficulty associated with electroweak penguins.
The ratio of partial decay rates for charged and neutral $B$ mesons to $K \pi$ final states provides information on the weak phase $\gamma \equiv {\rm Arg} (V_{ub}^*)$ when augmented with information on the CP-violating asymmetry in the…
In the presence of penguin contributions, the indirect CP asymmetry in B^0(t) --> pi^+ pi^- measures sin 2alpha_{eff}, where alpha_{eff} deviates from the true value of the CKM phase alpha by an amount theta, i.e. alpha_{eff} = alpha +…
In charmless nonleptonic B decays to \pi\pi or \rho\rho, the "color allowed" and "color suppressed" tree amplitudes can be studied in a systematic expansion in \alphas(mb) and \Lambda/mb. At leading order in this expansion their relative…
The 2.5 sigma discrepancy between theory and experiment observed in the difference Delta ACP = ACP(B- --> pi0 K-) - ACP(Bb0 --> pi+ K-) can be explained by a new electroweak (EW) penguin amplitude. Motivated by this result, we have analyzed…
Current data of charmless B meson decays to two pseudoscalar mesons (PP) and one vector and one pseudoscalar mesons (VP) are analyzed within the framework of flavor SU(3) symmetry, a working principle that we have tested by allowing…
Recently Ciuchini, Pierini and Silvestrini proposed a method for constraining CKM parameters in B->K pi pi and B_s-> K pi pi through phase measurements of amplitudes involving I=3/2 K*pi final states. We show that complementary information…
The unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix has been well established by both direct and indirect measurements without any evidence of discrepancy. The CKM weak phase $\alpha$ is directly measured using an isospin analysis…
Based on the most recent data in charmless B decays including the very recently reported large direct CP violations, it is shown that the weak phase gamma can well be extracted without two-fold ambiguity even only from two decay modes…