相关论文: Determining alpha and gamma - theory
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…
When collaborating with an AI system, we need to assess when to trust its recommendations. If we mistakenly trust it in regions where it is likely to err, catastrophic failures may occur, hence the need for Bayesian approaches for…
We have measured the branching fraction and photon energy spectrum for the radiative penguin process b -> s gamma. We find BR(b -> s gamma) = (3.21 +- 0.43 +- 0.27 +0.18 -0.10) 10^(-4), where the errors are statistical, systematic, and from…
Using the soft-collinear effective theory we derive the factorization theorem for the decays B-> M1 M2 with M{1,2}= pi,K, rho,K*, at leading order in Lambda/E_M and Lambda/mb. The results derived here apply even if alpha_s(E_M Lambda) is…
We present a general parametrization of $B^\pm\to\pi^\pm K, \pi^0K^\pm$ and $B_d\to\pi^0 K, \pi^\mp K^\pm$ decays, taking into account both electroweak penguin and rescattering effects. This formalism allows -- among other things -- an…
We discuss how to extract the weak phase alpha from present data on B--> rho+- pi-+ decays. Introducing alpha_{eff} and constraining the difference from alpha using flavor SU(3), one arrives at alpha=(95+- 16) degrees, if a testable…
Charmless B->PP decays are studied using flavor SU(3) symmetry. Amplitude with charming penguin topology is considered for two cases: with zero and with arbitrary strong phase. Two sets of data (an older and the most recent one) are used in…
We present results of a unitary triangle fit based on the scan method. This frequentist approach employs Gaussian uncertainties for experimental quantities, but makes no arbitrary assumptions about the distribution of theoretical errors.…
Various strategies for extracting or constraining the weak phase gamma with controlled theoretical uncertainties are reviewed. Measurements of the rates for the hadronic decays B^+- -> pi K provide largely model-independent information on…
We summarise the most recent results of the Belle experiment about flavour changing neutral current (FCNC) radiative and (semi-) leptonic B decays. In particular, we report about the first observation of the decays B->K*l+l-, B->phi K…
We give an overview of various determinations of $\gamma/\phi_3$ with the help of $B_s$ decays into charmed final states, distinguishing between transitions with tree and penguin contributions and pure tree decays. In the corresponding…
We study the effects of electroweak penguin (EWP) amplitudes in $B$ meson decays into two charmless pseudoscalars in the approximation of retaining only the dominant EWP operators $Q_9$ and $Q_{10}$. Using flavor SU(3) symmetry, we derive a…
Radiative penguin decays provide an indirect probe for physics beyond the Standard Model and contribute to the determination of the CKM matrix elements. Copious quantities of B mesons produced at the B-Factories permit precision…
The angle gamma of the standard CKM unitarity triangle can be determined from B -> D K decays with a very small irreducible theoretical error, which is only due to second-order electroweak corrections. We study these contributions and…
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…
We report on dispersive and finite energy sum rule analyses of the electroweak penguin matrix elements < (pi pi) | Q_{7,8} | K > in the chiral limit. We accomplish the correct perturbative matching (scale and scheme dependence) at NLO in…
In this report, experimental prospects for the inclusive analysis of the radiative B decays and electroweak penguin decays at the super B factories are presented.
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,…
Self-consistent random phase approximation (RPA) approaches in the relativistic framework are applied to calculate the isospin symmetry-breaking corrections $\delta_c$ for the $0^+\to0^+$ superallowed transitions. It is found that the…
We propose a new method to extract the CKM phase angle \gamma (\equiv \phi_3) from the isospin analysis in B \to K \pi decays. Unlike previously proposed methods, we do not employ flavor SU(3) symmetry, so that this method is free from the…