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Related papers: The CP-violating asymmetry in K_L -> pi+ pi- e+ e-

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We investigate the possible sizes of all the CP-violating asymmetries offered by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated by…

High Energy Physics - Phenomenology · Physics 2023-07-21 Diganta Das , Jaydeb Das , Girish Kumar , Niladribihari Sahoo

The decay bar B -> bar K* (-> bar K pi) l+ l- offers great opportunities to explore the physics at and above the electroweak scale by means of an angular analysis. We investigate the physics potential of the seven CP asymmetries plus the…

High Energy Physics - Phenomenology · Physics 2011-03-23 Christoph Bobeth , Gudrun Hiller , Giorgi Piranishvili

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…

High Energy Physics - Phenomenology · Physics 2010-02-17 O. Leitner , X. -H. Guo , A. W. Thomas

We present measurements of CP-violating asymmetries in the decay B0 -> a_1(1260)^{+-} pi^{-+} with a_1(1260)^{+-} -> pi^{-+} pi^{+-} pi^{+-}. The data sample corresponds to 384 million B B-bar pairs collected with the BaBar detector at the…

High Energy Physics - Experiment · Physics 2007-05-23 F. Palombo

We update the CP-violating asymmetries in K^+ -> 3 pi. In particular we study Delta g_C and Delta g_N -the asymmetries in the slope g. We emphasize its complementarity to the direct CP-violation parameter epsilon_K' and the large…

High Energy Physics - Phenomenology · Physics 2007-05-23 Elvira Gamiz , Joaquim Prades , Ignazio Scimemi

The difference between the CP asymmetries of the $B^0 \to K^+ \pi^-$ and $B^+ \to K^+ \pi^0$ decays has been recently confirmed with an evidence larger than $5\sigma$'s. We discuss it as a possible signal of new physics associated with new…

High Energy Physics - Phenomenology · Physics 2009-11-18 S. Khalil , A. Masiero , H. Murayama

Direct CP violations in $B_{l4}$ decays ($B^\pm \to \pi^+\pi^- l^\pm {\nu}_l$) are investigated within the Standard Model (SM) and also in its extensions. In the decay processes, we include various excited states as intermediate states…

High Energy Physics - Phenomenology · Physics 2016-08-25 C. S. Kim , Jake Lee , W. Namgung

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…

High Energy Physics - Experiment · Physics 2008-11-26 BaBar Collaboration , B. Aubert

We study rare exclusive B decays based on the quark-level transition b->s(d)l^+l^-, where l=e or mu, in the context of supersymmetric theories with minimal flavour violation. We present analytic expressions for various mixing matrices in…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Krüger , J. C. Romão

We present a measurement of the time-dependent CP-violating asymmetries in neutral B decays to the $\pi^+\pi^-$ CP eigenstate, and an updated measurement of the charge asymmetry in $B^0\to K^+\pi^-$ decays. In a sample of 33 million…

High Energy Physics - Experiment · Physics 2008-11-26 The BABAR Collaboration , H. Aubert

Four topics in theory of CP violation are reviewed. (a) CP violation in $B$ decays: We describe a new clean way of constraining the angle $\gamma$ of the unitarity triangle and how new CP violation in decay amplitudes can signal new…

High Energy Physics - Phenomenology · Physics 2009-09-25 Yosef Nir

The electroweak CP violating rate asymmetries in the decay $b \to d l^+ l^-$ are reexamined in detail and updated. In particular, the rate asymmetries are studied when one of the final state leptons is polarised. We find an estimate for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. S. Babu , K. R. S. Balaji , I. Schienbein

We point out that, if the direct CP asymmetries in the $D \to \pi^+ \pi^-$ and $D \to K^+ K^-$ decays are unequal, the indirect CP asymmetries as measured in these modes are necessarily unequal. This nonuniversality of indirect CP…

High Energy Physics - Phenomenology · Physics 2014-06-04 Amol Dighe , Diptimoy Ghosh , Bhavik P. Kodrani

We investigate the CP violating asymmetry, the forward backward asymmetry and the CP violating asymmetry in the forward-backward asymmetry for the inclusive B->X_d \ell^+\ell^- decays for the \ell=e,\mu \tau channels in the standard model.…

High Energy Physics - Phenomenology · Physics 2009-11-10 Zeynep Deniz Eygi , Gursevil Turan

Rare kaon decays are an important testing ground of the electroweak flavor theory: They can provide new signals of CP-violating phenomena. The interplay of long-distance QCD effects in strangeness-changing transitions can be analyzed with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fabrizio Gabbiani

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…

High Energy Physics - Phenomenology · Physics 2010-11-01 C. Q. Geng , I. J. Hsu , Y. C. Lin

I briefly review CP violation in the B system, concentrating on B -> pi K decays. I discuss how to deal with electroweak-penguin contributions to these decays using flavour SU(3). With these, I show that the entire unitarity triangle can be…

High Energy Physics - Phenomenology · Physics 2014-11-17 Maxime Imbeault

We present a novel method to search for a new CP-violating phase in b -> ss~ss~s transition using B -> phi phi Xs decays, where Xs represents a final state with a specific strange flavor such as K+/-, K*+/-, or K+/-pi-/+. Direct CP…

High Energy Physics - Phenomenology · Physics 2009-11-10 Masashi Hazumi

CP violation leads to a difference between the parameters $g^+$ and $g^-$ describing the energy distributions of the charged pions produced in the $K^+ \to\pi^0 \pi^0 \pi^+$ and $K^- \to \pi^0\pi^0 \pi^-$ decays. We study the difference…

High Energy Physics - Phenomenology · Physics 2009-11-11 Göran Fäldt , Evgeny Shabalin

We calculate the direct CP violating asymmetry parameter, $a_{CP}$, for $B \to \pi^{+} \pi^{-} \pi$ and $B \to \pi^{+} \pi^{-} K$ decays, in the case where $\rho^0-\omega$ mixing effects are taken into account. We find that the direct CP…

High Energy Physics - Phenomenology · Physics 2010-02-17 O. Leitner , Xin-Heng Guo , A. W. Thomas