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Related papers: CP Conserving and Violating Contributions to $K_L\…

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The rare decay $K_L\to\pi^0\nu\bar\nu$ is dominated by direct CP violation and can be computed with extraordinarily high precision. In principle also a CP conserving contribution to this process can arise within the Standard Model. We…

High Energy Physics - Phenomenology · Physics 2009-10-09 Gerhard Buchalla , Gino Isidori

We study the CP conserving and violating contributions to the decay of $\knng$ in the standard model. In our analysis, we use the form factors for $K\to\gamma$ transitions calculated directly in the entire physical range of momentum…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. Q. Geng , C. C. Lih , C. C. Liu

The decay $K_L \to \gamma \nu \bar{\nu}$ is investigated beyond the standard model. Interestingly, the upper limit of the CP-conserving and CP-violating branching ratios of the decay, induced from the possible extensions of the standard…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ji-Hao Jiang , Dao-Neng Gao , Mu-Lin Yan

Data indicate that $\Delta I=1/2$ transitions account for 4.5-4.7% of both CP conserving and CP violating $K \to 2\pi$ decays, as well as CP conserving radiative $K \to \pi\pi\gamma$ processes. Observed $K \to \pi\pi\gamma/\pi\pi$ branching…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michael D. Scadron , George Rupp , Eef van Beveren

A brief review of CP violation in $K$ and $B$ decays is given. While the observables $\varepsilon$ and Re$(\varepsilon'/\varepsilon)$ describing CP violation in neutral $K$ decays do not allow a powerful test of the CKM mechanism of CP…

High Energy Physics - Phenomenology · Physics 2009-10-30 Robert Fleischer

The recent Belle and Babar measurements of the branching ratios $B^- \to \pi^+ \pi^- K^-$ and $B^- \to K^+ K^- K^-$ and $B^\pm \to \chi_{c0} K^\pm$ have renewed interests in these decays as another mean to look for direct CP violation in B…

High Energy Physics - Phenomenology · Physics 2017-08-23 T. N. Pham

We report observations of CP violation in the decays B0 -> K+pi- and B0 -> pi+pi- in a sample of 383 million Y(4S) -> BBbar events. We find 4372 +/- 82 B0 -> K+pi- decays and measure the direct CP-violating charge asymmetry Akpi = -0.107…

High Energy Physics - Experiment · Physics 2019-08-14 B. Aubert

We calculate the different contributions to the decay $K_{L}\to \pi ^{0}\nu \bar{\nu}$ that arise if the neutrinos are massive. In spite of a chiral enhancement factor, we find that these contributions are negligibly small. Compared to the…

High Energy Physics - Phenomenology · Physics 2010-02-03 Gilad Perez

We present an updated analysis of the rare decay $K_{L}\to\pi^{0}\mu^{+}\mu^{-}$ within the Standard Model. In particular, we present the first complete calculation of the two-photon CP-conserving amplitude within Chiral Perturbation…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gino Isidori , Christopher Smith , Rene Unterdorfer

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…

High Energy Physics - Phenomenology · Physics 2009-10-28 Carl Carlson , Greg Dorata , Marc Sher

Motivated by recent Belle measurement of the branching ratios $B^- \to \pi^+ \pi^- K^-$ and $B^- \to K^+ K^- K^-$ and $B^\pm \to \chi_{c0} K^\pm$, we investigate the CP violating asymmetry in the partial widths for the decays $B^- \to \pi^+…

High Energy Physics - Phenomenology · Physics 2015-06-25 S. Fajfer , R. J. Oakes , T. N. Pham

We update the theoretical analysis of the CP-violating asymmetry in the decay K_L -> pi+ pi- e+ e-, relying on chiral perturbation theory and on the most recent phenomenological information. With the experimentally determined magnetic…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. Ecker , H. Pichl

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…

High Energy Physics - Phenomenology · Physics 2010-11-01 Hai-Yang Cheng

We search and find no evidence for CP violation in tau decays into the K pi nu final state. We provide confidence limits on the imaginary part of the coupling constant Lambda, describing a relative contribution of the CP violating processes…

High Energy Physics - Experiment · Physics 2010-04-08 G. Bonvicini , CLEO Collaboration

In the framework of perturbative QCD approach, we calculate the branching ratio and CP asymmetry for $B_{s}^0(\bar{B}_{s}) \to \pi^{\pm} K^\mp$ and $B_{s}(\bar{B}_{s})\to \pi^{0}\bar{K}^{0}(K^{0})$ decays. Besides the usual factorizable…

High Energy Physics - Phenomenology · Physics 2014-11-18 Xian-Qiao Yu , Ying Li , Cai-Dian Lü

We have collected a 43 event sample of the decay $K_L\to e^+e^-\mu^+\mu^-$ with negligible backgrounds and measured its branching ratio to be $(2.62 \pm 0.40 \pm 0.17)\times 10^{-9} $. We see no evidence for CP violation in this decay. In…

High Energy Physics - Experiment · Physics 2008-11-26 Alavi-Harati

We consider various contributions to the nonresonant decay $B^\pm\rightarrow \pi^+\pi^-\pi^\pm$, both of the long-distance and short-distance types with the former providing for most of the branching ratio, predicted to be…

High Energy Physics - Phenomenology · Physics 2010-11-01 Deshpande , Eilam , He , Trampetic

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…

High Energy Physics - Phenomenology · Physics 2009-10-30 Dong-Sheng Du , Mao-Zhi Yang

In the Minimal Supersymmetric Standard Model (MSSM) with complex parameters, one-loop corrections to the decay of a stop into a bottom-quark and a chargino can lead to a CP violating decay rate asymmetry. We perform a detailed numerical…

High Energy Physics - Phenomenology · Physics 2009-09-23 Sebastian M. R. Frank

We analyze the decay $K_L \to \pi^0 \nu \bar \nu$ in a model independent way. If lepton flavor is conserved the final state is (to a good approximation) purely CP even. In that case this decay mode goes mainly through CP violating…

High Energy Physics - Phenomenology · Physics 2009-10-30 Yuval Grossman , Yosef Nir
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