Related papers: Revisiting Kaon Physics in General $Z$ Scenario
Recently, the LHCb and CDF collaborations reported a surprisingly large difference between the direct CP asymmetries, Delta A_CP, in the D0 -> K+ K- and D0 -> pi+ pi- decay modes. An interesting question is whether this measurement can be…
The measured B -> pi pi, pi K branching ratios exhibit puzzling patterns. We point out that the B -> pi pi hierarchy can be nicely accommodated in the Standard Model (SM) through non-factorizable hadronic interference effects, whereas the B…
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…
With the wealth of new data from the B-factories, b -> d penguin decays become available for study, in addition to their b -> s counterparts that have proven an indespensable tool for the exploration of new-physics effects in flavour…
The quantities $\epsilon_K^\prime$ and $\epsilon_K$ measure the amount of direct and indirect CP violation in $K\to \pi\pi$ decays, respectively. Using the recent lattice results from the RBC and UKQCD Collaborations and a new compact…
CP violation due to interference between $K_L$ and $K_S$ decays into $\pi ^+\pi^-\gamma$ is analyzed in the Standard Model. The CP-violating parameter $\epsilon'_{+- \gamma}$, which is the difference between $\eta_{+-\gamma}$ and…
We consider several hints for new physics involving CP-asymmetries in B-decays and interpret them in terms of generic contributions to effective Wilson coefficients. The effects we focus on are: the differences in the fitted value of sin(2…
The recent observation of B_d -> pi^0 pi^0 at the B factories with a surprisingly large branching ratio represents a challenge for theory, and complements the amazingly small B_d -> pi^+ pi^- rate. We point out that all puzzling B -> pi pi…
We investigate the effect of an extra fourth quark generation and FCNC mediated $Z$ and $Z'$ bosons on the rare decay mode $B^- \to \phi \pi^-$. In the standard model, this mode receives only $b \to d$ penguin contributions and therefore,…
Direct CP violation in B^0-> K^+\pi^- decay has emerged at -10% level, but the asymmetry in B^+ -> K^+\pi^0 mode is consistent with zero. This difference points towards possible New Physics in the electroweak penguin operator. We point out…
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…
The high precision to which the standard model has been confirmed implies that new physics effects have to be small in the observed processes. Together with the outstanding precision expected from present and future collider experiments…
We study penguin-mediated $\bar{B}_{d(s)}\to\bar{K}^{*0}(K^{*0})\phi$ transitions, proposing a new optimised observable $L_{K^*\phi}$ from the ratio of the corresponding branching ratios of these decays, with limited hadronic uncertainties…
Recently, the standard model prediction of $\epsilon'/\epsilon$ was improved, and a discrepancy from the experimental results was reported at the $2.9\sigma$ level. We study the chargino contributions to $Z$ penguin especially with the…
A new experimental analysis of $B\to K\pi$ decays provides finite experimental values for the contributions from interference terms between the dominant penguin amplitude and the color-favored and color-suppressed tree amplitudes. These…
Recent CP violation results in B decays suggest that Z penguins may have large weak phase. This can be realized by the four generation (standard) model. Concurrently, B to Xs l+ l- and Bs mixing allow for sizable Vt's* Vt'b only if it is…
Recently, we have seen interesting progress in the exploration of CP violation in B^0_d -> pi^+ pi^-: the measurements of mixing-induced CP violation by the BaBar and Belle collaborations are now in good agreement with each other, whereas…
It is stressed that a measurement of the electric dipole amplitude for direct photon emission in $\kpm$ decays through its interference with inner bremsstrahlung is important for differentiating among various models. Effects of amplitude CP…
We scrutinize the penguin dominated $ B_s \to K^+ K^-$ decay mode involving $b \to s$ quark level transition in family non-universal $Z^ \prime$ and vector-like down quark model. There is discrepancy in the standard model branching ratio…
The precision of the CP phases $2\beta$ and $2\beta_s$ determined from the mixing-induced CP asymmetries in $B_d\to J/\psi K_S$ and $B_s\to J/\psi \phi$, respectively, is limited by the unknown long-distance contribution of a penguin…