相关论文: Direct CP Violation in $K_L\to\pi^+\pi^-\gamma$

In perturbative QCD approach, based on the first order of isospin symmetry breaking, we study the direct $CP$ violation in the decay of $\bar{B}_s^0\to\rho(\omega )K^{*0}\to {\pi^+}{\pi^-}K^{*0}$. An interesting mechanism is applied to…

Within the framework of Standard Model, the exclusive decay mode $B\to \pi \gamma \gamma $ is studied. Although the usual short distance contribution is small compared to the similar $B\to K\gamma\gamma$ mode, the process offers the…

We report measurements of the branching fraction and CP violation parameters in B0 -> D+D- decays. The results are based on a data sample that contains 535 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance, with the Belle detector…

We report on a search for the decay K_L -> pi^0 nu nubar, carried out as a part of E799-II, a rare K_L decay experiment at Fermilab. Within the Standard Model, the K_L -> pi^0 nu nubar decay is dominated by direct CP violating processes,…

We investigate CP violation in the decay process $\bar B_{s} \rightarrow V V \rightarrow K^{+}K^{-}K^{+}K^{-}$ within the framework of perturbative QCD, where V represents vector mesons $\phi$, $\rho$, and $\omega$. We analyze the mixing…

New physics contributions to the $Z$ penguin are revisited in the light of the recently-reported discrepancy of the direct CP violation in $K\to\pi\pi$. Interference effects between the standard model and new physics contributions to…

We search for CP violation in a sample of $4.7\times10^4$ Cabibbo-suppressed $D^0 \to K^+ K^- \pi^+ \pi^-$ decays. We use 470{\rm fb}^{-1} of data recorded by the BaBar detector at the PEPII asymmetric-energy $e^+e^-$ storage rings running…

CP violation in $B$ decays is reviewed in the Standard Model (SM) and beyond the SM. The present explanation of CP violation in terms of a phase in the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be tested through a variety of CP asymmetries…

The amplitudes of the K^{\pm} \to 3\pi and K \to 2\pi decays are expressed in terms of different combinations of one and the same set of CP-conserving and CP-odd parameters. Extracting the magnitudes of these parameters from the data on K…

We calculate the branching ratio and direct CP asymmetry in nonleptonic two body B decays B^+- ->\pi^+- \eta'. It is shown that the tree diagram and gluon fusion mechanism via penguin diagram have comparable contributions to these decays…

In the standard model, direct CP-violating asymmetries for $B^\pm \to \pi^\pm K$ are roughly 2% based on perturbative calculation. Rescattering effects might enhance it to at most (20-25)%. We show that lepton-number-violating couplings in…

Evidence of CP violation in the charm sector has been observed recently by the LHCb and CDF Collaborations. The issue of whether it can be accommodated within the standard model (SM) is examined in this talk. We conclude that the CP…

We present measurements of the time-dependent CP-violation parameters S and C in B^0 --> eta' K^0 decays. The data sample corresponds to 384 million B Bar pairs produced by e^+ e^- annihilation at the Y(4S). The results are S = 0.58 +- 0.10…

The general production {\it and} decay mechanism of $\ttbar$ in future high-energy $\epem$ colliders has been investigated in a model-independent way, focusing on an observation of possible CP violation. Angular asymmetries sensitive to CP…

We discuss direct CP violation in three-body decays of $B$ meson such as $B^\pm \to K^\pm\pi^+\pi^-$, which involves various intermediate resonance states, such as $B^\pm \to K^*_i \pi^\pm$ and $B^\pm \to \rho K^\pm$, where $K^*_i$…

The decay $K_L\rightarrow \pi^o\nu\overline{\nu}$ is an excellent probe of the nature of CP violation. It is almost entirely CP-violating, and hadronic uncertainties are negligible. Experiments which hope to detect the decay are currently…

We present a measurement of the time-dependent CP-violating asymmetry in $B^0 \to K^{*}_0\gamma$ decays with $K^{*}_0\to K^{0}_s\pi^0$ based on 232 million $\Upsilon(4\mathrm{S})\to B\bar{B}$ decays collected with the BaBar detector at the…

In the perturbative QCD (PQCD) approach we study the direct $CP$ violation in $B^+_{c}\rightarrow D_{(s)}^+\rho^0(\omega) \rightarrow D_{(s)}^+\pi^+\pi^-$ via the $\rho-\omega$ mixing mechanism. We find that the $CP$ violation can be…

A Dalitz-plot analysis of Bd(t) -> rho pi -> pi+ pi- pi0 decays allows one to obtain the CP-violating phase \alpha. In addition, one can extract the various tree (T) and penguin (P) amplitudes contributing to these decays. By comparing the…

We study both CP conserving and violating contributions to the decay $K_L\to\pi^+\pi^-\nu\bar{\nu}$. We find that the decay branching ratio is dominated by the CP conserving part. In the standard CKM model, we estimate that for $m_t\sim…