相关论文: Probing new physics in B -> phi pi decay
We underline the theoretical interest of the vector-vector penguin decay $B_s \to \phi \phi$, very clean from the experimental point of view. The CP-violation asymmetry $A_{CP}^{mix}$ comes from the interference of mixing and decay…
In this work we study the CP violation for $\bar{B^0}\to J/\psi K_s$ and $\bar{B^0}\to \phi K_s$ up to leading and next-to-leading order QCD corrections in the standard model, two-Higgs-doublet model and the minimal supersymmetric extension…
We investigate the CP-averaged branching ratios, the polarization fractions, the relative phases, and the CP-violating asymmetries of the penguin-dominated $B \to \phi K_1(1270) $ and $ \phi K_1(1400)$ decays in the perturbative QCD(pQCD)…
Measurements of CP violation in $B^0_d\to J/\psi K_{\rm S}^0$ and $B^0_s\to J/\psi \phi$ decays play key roles in testing the quark-flavour sector of the Standard Model. The theoretical interpretation of the corresponding observables is…
Measurements of the branching fraction ratio ${\cal{B}(\phi \to \mu^+ \mu^-)/\cal{B}(\phi\to e^+e^-)}$ with ${D_{s}^{+} \to \pi^{+} \phi}$ and ${D^{+} \to \pi^{+} \phi}$ decays, denoted $R^{s}_{\phi \pi}$ and $R^{d}_{\phi \pi}$, are…
If physics beyond the standard model is present in B decays, experimental measurements seem to suggest that it principally affects those processes with significant b->s penguin amplitudes. It was recently argued that, in general, such…
We present recent results from the \babar Collaboration on radiative decays. These include searches for new physics via measurements of several observables such as the time-dependent $CP$ asymmetry in $B^0 \to K^0_S \pi^- \pi^+ \gamma$…
The exclusive semileptonic $B\to \pi(\rho) e\nu$ decays are studied in the framework of the relativistic quark model based on the quasipotential approach in quantum field theory. The large recoil momentum of the final $\pi(\rho)$ meson…
The pure penguin process $B\to \phi K^*$ is one of the most important probes of physics beyond the Standard Model. Recently BaBar and Belle have measured the unexpectedly large transverse polarization in the decays $B\to \phi K^*$, which…
We study charmless pure annihilation type radiative B decays within the QCD factorization approach. After adding the vertex corrections to the naive factorization approach, we find that the branching ratios of $\bar{B}^0_d\to\phi\gamma$,…
A search for the decays B --> rho(770) gamma and B0 --> omega(782)gamma is performed on a sample of 211x10^6 Y(4S)->BBbar events collected by the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. No evidence for the decays…
Some discrepancies between theory and experiment in the B -> pi K decays suggest the possibility of a new physics contribution with the structure of an electroweak penguin amplitude. If such a scenario is realised in nature, the branching…
Using a dataset corresponding to an integrated luminosity of 3.0 fb$^{-1}$ collected in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV, the $B_s^0 \to \phi \phi$ branching fraction is measured to be \[ \mathcal{B}(B_s^0 \to \phi…
Motivated by recent CLEO measurements of $B\to\pi K$ modes, we investigate their implications for the CKM angle $\gamma$ and a consistent description of these decays within the Standard Model. Interestingly it turns out that already the…
We evaluate $B\to K\pi$ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that…
The $b \to s$ penguin amplitude affects a number of $B$ meson decays to two pseudoscalar ($P$) mesons in which potential anomalies are being watched carefully, though none has yet reached a statistically compelling level. These include (a)…
The QCD factorization (QCDF) method usually contains infrared divergences which introduce large model dependence to its predictions on charmless B decays. The amplitudes of charmless B decays can be decomposed into "tree" and "penguin"…
Using 65 million $\Upsilon(4S)\to B\bar{B}$ events collected with the BABAR detector at the PEP-II $e^{+}e^{-}$ storage ring at the Stanford Linear Accelerator Center, we measure the color-favored branching fractions ${\cal B}(\bar{B^{0}}…
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…
In the study of two-body charmless B decays as a mean of looking for direct CP-violation and measuring the CKM mixing parameters in the Standard Model, the short-distance penguin contribution with its absorptive part generated by charm…