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Related papers: CP Violation in Fourth Generation Quark Decays

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Within the Standard model with the 4th generation quarks b' and t' we have analyzed CP-violating flavor changing neutral current processes t -> cX; b'-> sX, b'-> bX,t'-> cX, and t'-> tX, with X=Z,H,gamma,g, by constructing and employing…

High Energy Physics - Phenomenology · Physics 2014-11-20 G. Eilam , B. Melic , J. Trampetic

Analytic expressions for the angular distributions of the $b$-quarks associated with single $t$-quark production in $p \bar p \to W^* \to t \bar b \to b \bar b W$ and of the leptons from the subsequent decay $W \to l\nu$ are obtained in the…

High Energy Physics - Phenomenology · Physics 2009-11-07 E. Christova , S. Fichtinger , S. Kraml , W. Majerotto

In order to observe a signal of possible CP violation in top-quark couplings, we study top-quark production and decay under the conditions of the Tevatron upgrade. Transverse energy asymmetries sensitive to CP violation are defined.…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Grzadkowski , B. Lampe , K. J. Abraham

We study a decay rate asymmetry of the top quark in the supersymmetric standard model, taking into account the constraints from the electric dipole moments of the neutron and the electron. One CP-violating phase contained in the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Mayumi Aoki , Noriyuki Oshimo

Combining the measured B_s mixing with b \to s\ell^+\ell^- rate data, we find a sizable 4 generation t' quark effect is allowed, for example with m_{t'} \sim 300 GeV and V_{t's}^*V_{t'b} \sim 0.025 e^{\pm i 70^\circ}, which could underly…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wei-Shu Hou , Makiko Nagashima , Andrea Soddu

The Standard Model predicts a very small CP violation phase $\sin2\Phi^{\rm SM}_{B_s} \simeq -0.04$%= \arg M_{12} \simeq \arg\,(V^*_{ts}V_{tb})^2$ in $B_s$--$\bar B_s$ mixing. %, i.e. of order $\lambda^2\eta$. Any finite value of…

High Energy Physics - Phenomenology · Physics 2014-11-20 W. S. Hou , C. Y. Ma

LHCb collaboration measured CPV at the level of one percent in the difference of assymetries in $D^0(\bar D^0)\to \pi^+ \pi^-, K^+ K^-$ decays. If confirmed on a larger statistics and final systematics this would mean New Physics…

High Energy Physics - Phenomenology · Physics 2012-04-06 A. N. Rozanov , M. I. Vysotsky

The phase convention independent measure of CP violation for three generations of leptons is evaluated at different energy scales. Unlike in the quark sector, this quantity does not vary much between the weak and the grand unification…

High Energy Physics - Phenomenology · Physics 2014-11-17 Cheng-Wei Chiang

CP violation in H^\pm decays into the three possible decay modes into ordinary particles, 1) H^\pm \to tb, 2) H^\pm \to \nu \tau and 3) H^\pm \to W^\pm h^0 is considered. Analytic expressions and numerical results for the CP violating decay…

High Energy Physics - Phenomenology · Physics 2009-04-14 Ekaterina Christova , Helmut Eberl , Elena Ginina

The distributions of the single decay b-quarks and leptons from e^+e^- \to t\bar t assuming CP violation are reviewed. Different asymmetries, sensitive independently to CP violation in the production and in the decay, and sensitive to the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ekaterina Christova

It is shown that in the approximation of $|\frac{q}{p}|$=1 the CP violation in $B^0_{d,s} \to l^+ l^-$ decays vanishes in SM. In a 2HDM with CP violating phases and MSSM the CP asymmetries depend on the parameters of models and can be as…

High Energy Physics - Phenomenology · Physics 2009-10-31 Chao-Shang Huang , Liao Wei

We show that a fourth family of quarks with $m_{t'}$ in the range of (400 - 600) GeV provides a rather simple explanation for the several indications of new physics that have been observed involving CP asymmetries of the b-quark. The…

High Energy Physics - Phenomenology · Physics 2010-01-21 Amarjit Soni , Ashutosh Kumar Alok , Anjan Giri , Rukmani Mohanta , Soumitra Nandi

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

The baryon asymmetry of the Universe requires CP violation, but the Standard Model falls short by a factor of $10^{-10}$ or more. Starting from a clue at the $B$ factories, we point out that the large Yukawa couplings of the sequential…

High Energy Physics - Phenomenology · Physics 2008-10-27 Wei-Shu Hou

CP violating effects in top quark pair production at the future 2 TeV $p\bar p$ Tevatron and 14 TeV $pp$ LHC colliders are investigated. We study three kinds of CP violating sources:the supersymmetric CP-odd phase of the stop trilinear soft…

High Energy Physics - Phenomenology · Physics 2009-10-31 Hong-Yi Zhou

A decay rate asymmetry of the top quark is discussed within the framework of the supersymmetric standard model. Although new sources of CP violation in this model are severely constrained from the electric dipole moments of the neutron and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mayumi Aoki

Results are presented on a search for CP violation in the production and decay of top quark-antiquark pairs in the lepton+jets channel. The search is based on data from proton-proton collisions at 13 TeV, collected with the CMS detector,…

High Energy Physics - Experiment · Physics 2023-06-21 CMS Collaboration

How to account for the matter predominance of our Universe is a fundamental issue at the core of our existence. One condition is CP violation, but the Standard Model falls short by more than $10^{-10}$. Taking cue from a recent result from…

High Energy Physics - Phenomenology · Physics 2008-10-24 George W. S. Hou

We investigate the possibilities of searching for non-standard CP violation in $pp\to t\bar{t}X$ at multiple TeV collision energies. A general kinematic analysis of the underlying partonic production processes $gg\to t\bar{t}$ and…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Bernreuther , A. Brandenburg

We show that simultaneous precision measurement of the CP-violating phase in time-dependent Bs --> J/psi phi study and the Bs --> mu+ mu- rate, together with measuring m_t' by direct search at the LHC, would determine V_{t's}^*V_{t'b} and…

High Energy Physics - Phenomenology · Physics 2015-03-19 Wei-Shu Hou , Masaya Kohda , Fanrong Xu
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