相关论文: Direct CP Violation in $K_L\to\pi^+\pi^-\gamma$
Using a technique which employs a pair of solid scintillator regenerators, the E773 collaboration has measured several CP violation parameters in K meson decay at Fermilab. We report new results for the phase of eta_+-, the K_L-K_S mass…
We present a measurement of the direct CP violating asymmetry in the decay B0 -> K+pi- using 227 x 10^6 Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we observe a total signal…
The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting K_L and K_S decays into pi0pi0 and pi+pi-. The result for the CP violating parameter…
The amplitudes of $K \rightarrow \pi \gamma^* \rightarrow \pi e^+e^-$ and $K \rightarrow \pi \pi \gamma$ decays have been calculated within chiral Lagrangian approach including higher-order derivative terms and meson loops. The…
We report the first observation of a manifestly CP violating effect in the K(L)->pi+pi-e+e- decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle phi between the decay planes of the…
In 1988 the NA31 experiment presented the first evidence of direct CP violation in the $K^0\to\pi\pi$ decay amplitudes. A clear signal with a $7.2\,\sigma$ statistical significance was later established with the full data samples from the…
This is a pedagogical review of some selected topics of CP and T violation in the decays of K mesons. Diagonalization of the quark mass matrix and the emergence of the complex phase in both the standard and the left--right symmetric models…
We study the CP violating effects in the decay of $\eta\to\pi^+\pi^-\gamma$. We show that to have CP violation in the decay, one has to consider both linear and circular photon polarizations. In the standard model, the polarizations are…
We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi+/- pi-/+. Using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, we measure CP-averaged branching…
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…
We investigate in a phenomenological way, direct CP violation in the hadronic decays $B^{\pm,0} \to \pi^{+} \pi^{-} K^{\pm,0}$ where the effect of $\rho - \omega$ mixing is included. If $N_{c}^{eff}$ (the effective parameter associated with…
The likelihood of a sizable, direct CP-violating asymmetry in the decays $B^\mp\to K^\mp\eta$, is calculated within the framework of the model which originally predicted a sizeable asymmetry in $\pi^\mp\eta(\eta')$. It is shown in a…
We report an improved measurement of direct CP violation in the decay B0 --> K+pi-, and a search for CP violation in the decays B+ --> K+pi0 and B+ --> pi+pi0. The measured CP violating asymmetries are…
In perturbative QCD approach, we study the direct $CP$ violation in the decay of $\bar{B}_s^0\to\rho(\omega )\phi\to {\pi^+}{\pi^-}\phi$ via isospin symmetry breaking. An interesting mechanism involving the charge symmetry violating between…
We investigate allowed regions in observable space of B --> pi K, B_d --> pi^+pi^- and B_s --> K^+K^- decays, characterizing these modes in the Standard Model. After a discussion of a new kind of contour plots for the $B\to\pi K$ system, we…
Indirect CP violation in the $D^0$ system can be probed by measuring the parameter $A_{\Gamma}$, defined as the CP asymmetry of the effective lifetime of the $D^0$ meson decaying to a CP eigenstate. This can be significantly enhanced beyond…
Direct CP violation in the hadronic decays $\Bar{B}^{0} \to \pi^{+}\pi^{-} \pi^{0}$ is investigated near the peak of the $\rho^{0}$ taking into account the effect of $\rho - \omega$ mixing. Branching ratios for processes $B^{\pm,0} \to…
We study the determination of gamma from CP-violating observables in B -> pi+ pi- and B -> psi K_S. This determination requires theoretical input to one combination of hadronic parameters. We show that a mild assumption about this quantity…
We investigate the possibility of observing the direct CP violation in the decay modes $B^- \to D^0 D_s^-$ and $D^0 D^-$ within the Standard Model. Including the contributions arising from the tree, annihilation, QCD as well as electroweak…
We study direct CP violation in the hadronic decay $B^{\pm} \to \rho^{0}\pi^{\pm}$, including the effect of $\rho - \omega$ mixing. We find that the CP violating asymmetry is strongly dependent on the CKM matrix elements, especially the…