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

200 papers

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

Discovering CP-violating effects in the Higgs sector would constitute an indisputable sign of physics beyond the Standard Model. We derive constraints on the CP-violating Higgs-boson couplings to top and bottom quarks as well as to tau…

High Energy Physics - Phenomenology · Physics 2013-11-28 Joachim Brod , Ulrich Haisch , Jure Zupan

The existence of fourth family follows from the basics of the Standard Model. Because of the high masses of the fourth family quarks, their anomalous decays could be dominant, if certain criteria are met. This will drastically change the…

High Energy Physics - Phenomenology · Physics 2014-11-21 M. Sahin , S. Sultansoy , S. Turkoz

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harald Fritzsch , Zhi-zhong Xing

A viable formulation of gauge theory with extra generations in terms of quaternionic fields is presented. For the theory to be acceptable, the number of generations should be equal to or greater than 4. The quark-lepton mass matrices are…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. S. Lim

We demonstrate that the observed baryon asymmetry in the Universe can be accommodated in the extended Standard Model with sequential fourth generation fermions (SM4). We first construct the dimension-6 effective operators of the type…

High Energy Physics - Phenomenology · Physics 2026-05-28 Hsiang-nan Li

We study a two-Higgs-doublet model with four generalised CP symmetries in the scalar sector. Electroweak symmetry breaking leads automatically to spontaneous breaking of two of them. We require that these four CP symmetries can be extended…

High Energy Physics - Phenomenology · Physics 2008-12-18 M. Maniatis , A. von Manteuffel , O. Nachtmann

We study CP asymmetries in rare B decays within supersymmetry with a U(2)^3 flavour symmetry, motivated by the SUSY flavour and CP problems, the hierarchies in the Yukawa couplings and the absence so far of any direct evidence for SUSY.…

High Energy Physics - Phenomenology · Physics 2015-05-30 Riccardo Barbieri , Paolo Campli , Gino Isidori , Filippo Sala , David M. Straub

Possible anomalous single productions of the fourth standard model generation up and down type quarks at CERN Large Hadron Collider are studied. Namely, $p p \to u_4 (d_4) X$ with subsequent $u_4\to bW^{+}$ process followed by leptonic…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. Ciftci

The non-minimal flavour violating interactions of mirror quarks and new heavy gauge bosons in the Littlest Higgs model with T-parity (LHT) give rise to naturally large CP-violating effects in the B_s system. In view of a large new CP phase…

High Energy Physics - Phenomenology · Physics 2010-01-15 Monika Blanke , Andrzej J. Buras , Stefan Recksiegel , Cecilia Tarantino

Non-leptonic B_s decays into CP eigenstates that are caused by \bar b -> \bar cc\bar s quark-level transitions, such as B_s -> D_s^+D^-_s, J/psi eta^(') or J/psi phi, provide a powerful tool to search for ``new physics'', as the…

High Energy Physics - Phenomenology · Physics 2011-03-23 Patricia Ball , Robert Fleischer

In this presentation an account of the multi-lepton (electrons and muons) anomalies at the LHC is given. These include the excess production of opposite sign leptons with and without b-quarks, including a corner of the phase-space with a…

High Energy Physics - Phenomenology · Physics 2021-09-09 Bruce Mellado

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 give a description of why the existence of a fourth generation is likely to provide enough CP violation for baryogenesis, and trace how this observation came about. We survey the current experimental and theoretical pursuits and outline…

High Energy Physics - Phenomenology · Physics 2011-08-05 George W. S. Hou

A recent study [1] has shown that a simplified model predicting a heavy scalar of mass 270 GeV ($H$) that decays to a Standard Model (SM) Higgs boson in association with a scalar singlet of mass 150 GeV ($S$) can accommodate several…

High Energy Physics - Phenomenology · Physics 2019-10-18 Stefan von Buddenbrock , Alan S. Cornell , Yaquan Fang , Abdualazem Fadol Mohammed , Mukesh Kumar , Bruce Mellado , Kehinde G. Tomiwa

In this talk, we first make some brief comments on the phase-convention dependence of the CP-violating parameter \epsilon_B. A simple framework is then presented for analyzing new physics contributions to B^0-\bar{B}^0 mixing and their…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zhi-zhong Xing

We study various FCNC involving heavy quarks in the Standard Model (SM) with a sequential fourth generation. After imposing $B\to X_s\gamma$, $B\to X_sl^+l^-$ and $Z\to b\bar{b}$ constraints, we find ${\cal B}(Z\to s\bar{b}+\bar{s}b)$ can…

High Energy Physics - Phenomenology · Physics 2010-02-03 Abdesslam Arhrib , Wei-Shu Hou

We study the effects of sequential fourth quark generation in rare "B -> K(K*) l^+ l^-" decays induced by "b -> s" transition and in "B_s^0 - bar{B}_s^0" mixing. Using the experimental values on branching ratios of the "B -> X_s gamma" and…

High Energy Physics - Phenomenology · Physics 2009-01-07 T. M. Aliev , A. Ozpineci , M. Savci

The CP-violation necessary for the generation of the baryon asymmetry of the Universe $Y_B$ in the "flavoured" leptogenesis scenario can arise from the "low energy" PMNS neutrino mixing matrix $U$ and/or from the "high energy" part of…

High Energy Physics - Phenomenology · Physics 2010-09-20 E. Molinaro , S. T. Petcov

We study effects of beyond the Standard Model physics coupling third generation quarks to leptons of the first two generations. We parametrize these effects by dimension-six effective operators, and we also consider related simplified UV…

High Energy Physics - Phenomenology · Physics 2020-08-26 Daniel Stolarski , Alberto Tonero