相关论文: Difficulties in Obtaining Weak Phases from $b\to d…
We reanalyze the decay $B_d\to\pi^+\pi^-$ without assuming dominance of QCD penguins with internal top-quark exchanges. In that case the weak phase of the $\bar b \to\bar d$ QCD penguin amplitude is not related in a simple way to the CKM…
The decay rates for $B^0 \to K^+ \pi^-$, $B^+ \to K^0 \pi^+$, and the charge-conjugate processes were found to provide information on the weak phase $\gamma \equiv {\rm Arg}(V_{ub}^*)$ when the ratio $r$ of weak tree and penguin amplitudes…
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…
Several new strategies to extract CKM phases, including a determination of $\gamma$ from $B_{s(d)}\to J/\psi K_S$ decays and a general approach, which makes use of the angular distributions of certain $B_{d,s}$ modes, such as $B_d\to J/\psi…
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.
There are variety of methods which directly test for the presence of new physics in the b -> s flavour-changing neutral current (FCNC), but none which cleanly probe new physics in the b -> d FCNC. One possible idea is to compare the weak…
An analysis of $B \to K\pi$ decays is given, assuming a small elastic $\pi K $ rescattering phase difference.Using factorization model only for the tree-level and electroweak penguin amplitudes, we show that the strong penguin amplitude,…
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…
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…
We present strategies for determining electroweak penguins from experimental data. Using the CKM-angle $\gamma$ as one of our central inputs and making some reasonable approximations, we show that the $\bar b\to\bar s$ electroweak penguin…
We discuss a method for extracting CP phases from pairs of B decays which are related by flavor SU(3). One decay (B0 -> M1 M2) receives a significant bbar -> dbar penguin contribution. The second (B' -> M1' M2') has a significant bbar ->…
It is shown that the weak phase gamma=arg(-V_{ud}V^*_{ub}V_{cb}V_{cd}^*) can be determined using only untagged decays B/Bbar--> D K_S. In order to reduce the uncertainty in gamma, we suggest combining information from B^{+-}--> DK^{+-} and…
The decays $B_d\to\pi^+\pi^-$ and $B_s\to K^+K^-$ provide an interesting strategy to extract the CKM angle $\gamma$ at ``second-generation'' $B$-physics experiments of the LHC era. A variant for ``first-generation'' experiments can be…
Determinations of the CKM phase $\gamma$ from weak nonleptonic $B$ decays are affected by electroweak (EW) penguins and rescattering effects. In this talk it is explained how the EW penguin effects can be controlled with the help of SU(3)…
Recent results from CLEO on $B\to K\pi$ indicate that the phase $\gamma$ may be substantially different from that obtained from other fit to the KM matrix elements in the Standard Model. We show that $\gamma$ extracted using $B\to K\pi,…
We propose two independent methods to determine the CKM phase $\gamma$ and the tree and penguin amplitudes using neutral $B$ decays, assuming that the phase $\beta$ is known. Based on flavor SU(3) symmetry and SU(3) breaking effect, one…
The theoretical precision of the measurement of the $B^0_{d,s}$-$\bar B^0_{d,s}$ mixing phases $\phi_{d,s}$ through the benchmark decays $B^0_d\to J/\psi K_S$, $B^0_s\to J/\psi \phi$ and $B^0_s\to J/\psi f_0(980)$ is limited by doubly…
Electroweak penguin operators become important when $m_t \approx 174$ GeV. We discuss their implications for measuring CP violating phases $\alpha$, $\beta$ and $\gamma$.
The most common decay used for measuring 2beta_s, the phase of Bs-Bsbar mixing, is Bs -> J/psi phi. This decay is dominated by the colour-suppressed tree diagram, but there are other contributions due to gluonic and electroweak penguin…
We show that the CP phase \gamma can be obtained from measurements of Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)-. These decays are related by flavor SU(3) in the limit where spectator-quark contributions are small. If the…