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Related papers: The "4th generation", B-CP anomalies & the LHC

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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

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

The rare decays of $\Lambda_b$ baryon governed by the quark level transitions $ b \to s$, are investigated in the fourth quark generation model popularly known as SM4. Recently it has been shown that SM4, which is a very simple extension of…

High Energy Physics - Phenomenology · Physics 2015-03-17 R. Mohanta , A. K. Giri

We study some rare decays of $B_s$ meson governed by the quark level transitions $ b \to s$, in the fourth generation model popularly known as SM4. Recently it has been shown that SM4, which is a simple extension of the SM3, can…

High Energy Physics - Phenomenology · Physics 2013-05-30 R. Mohanta , A. K. Giri

We extend our recent work and study implications of the Standard Model with four generations (SM4) for rare B and K decays. We again take seriously the several 2-3 $\sigma$ anomalies seen in B, $B_s$ decays and interpret them in the context…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amarjit Soni , Ashutosh Kumar Alok , Anjan Giri , Rukmani Mohanta , Soumitra Nandi

We show that, if a fourth generation is discovered at the Tevatron or LHC, one could study CP violation in b' \to s decays. Asymmetries could reach 30% for b'\to sZ for m_{b'} \lesssim 350 GeV, while it could be greater than 50% for b'\to…

High Energy Physics - Phenomenology · Physics 2010-04-30 Abdesslam Arhrib , Wei-Shu Hou

We estimate the CP asymmetry A_{CP}(q^2) in the decays B --> X_s mu+ mu- and B --> X_d mu+ mu- in the standard model (SM) with an additional fourth generation. We use a parametrization that allows us to explore the complete parameter space…

High Energy Physics - Phenomenology · Physics 2010-02-08 Ashutosh Kumar Alok , Amol Dighe , Shamayita Ray

Using existing experimental information from K, B and D decays as well as electroweak precision tests and oblique parameters, we provide constraints and correlations on the parameters of the 4X4 mixing matrix for the Standard Model with…

High Energy Physics - Phenomenology · Physics 2011-07-04 Soumitra Nandi , Amarjit Soni

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

A 4th generation could be consistent with the recently measured $\Delta m_{B_s}$ as well as ${\cal B}(b\to s\ell^+\ell^-)$, which are SM-like, but generate large $\sin2\Phi_{B_s} \simeq -0.5$ to -0.7. The sign is determined by the hint for…

High Energy Physics - Phenomenology · Physics 2017-08-23 George W. S. Hou

We study D0-D0 mixing in the presence of a fourth generation of quarks. In particular, we calculate the size of the allowed CP violation which is found at the observable level well beyond anything possible with CKM dynamics. We calculate…

High Energy Physics - Phenomenology · Physics 2015-03-14 Andrzej J. Buras , Björn Duling , Thorsten Feldmann , Tillmann Heidsieck , Christoph Promberger , Stefan Recksiegel

A supersymmetric model with four generations is proposed, in which the top quark is approximately degenerate in mass with the $W^{\pm}$ gauge boson, $m_t\simeq m_W$, leading to values of $R_b$ in better agreement with the present…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Carena , H. E. Haber , C. E. M. Wagner

We study extensions of the standard model with a strongly coupled fourth generation. This occurs in models where electroweak symmetry breaking is triggered by the condensation of at least some of the fourth-generation fermions. With focus…

High Energy Physics - Phenomenology · Physics 2010-05-12 Gustavo Burdman , Leandro Da Rold , Oscar Eboli , Ricardo Matheus

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

The first evidence of new strong interactions may be a sufficiently massive fourth family observed at the LHC. The fourth family masses, of the leptons in particular, are constrained by the electroweak precision data, and this leads to…

High Energy Physics - Phenomenology · Physics 2009-11-11 B. Holdom

In top-pair events where at least one of the tops decays semi-leptonically, the identification of the lepton charge allows to tag not only the top charge but also that of the subsequent b quark. In cases where the b also decays…

High Energy Physics - Phenomenology · Physics 2013-06-12 Oram Gedalia , Gino Isidori , Fabio Maltoni , Gilad Perez , Michele Selvaggi , Yotam Soreq

The generalization of the MSSM to the case of four chiral fermion generations (4GMSSM) can lead to significant changes in the phenomenology of the otherwise familiar Higgs sector. In most of the 3GMSSM parameter space, the lighter CP-even…

High Energy Physics - Phenomenology · Physics 2013-05-29 R. C. Cotta , J. L. Hewett , A. Ismail , M. -P. Le , T. G. Rizzo

The CP violation in $K$ and B decays are discussed with the emphasize on the precise prediction for $\epsilon'/\epsilon$ and the new physics effects from a class of models with additional Higgs doublets and fermions. The contributions from…

High Energy Physics - Phenomenology · Physics 2017-08-23 Yue-Liang Wu , Yu-Feng Zhou

The LHCb experiment will search for New Physics in Bs mixing. The Bs mixing phase will be extracted from the measurement of the time-dependent CP asymmetry in exclusive Bs decays governed by the b -> ccbar s quark-level transition. Large…

High Energy Physics - Experiment · Physics 2007-10-30 LHCb collaboration , Johan Blouw

We study a warped extra-dimension scenario where the Standard Model fields lie in the bulk, with the addition of a fourth family of fermions. We concentrate on the flavor structure of the Higgs couplings with fermions in the flavor anarchy…

High Energy Physics - Phenomenology · Physics 2015-05-28 Mariana Frank , Beste Korutlu , Manuel Toharia
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