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

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We present a model which employs $CP\times Z_3$ symmetries where quark mixing and charged leptons masses are explained by following some texture. To achieve neutrino mass and mixing, we write a non-renormalizable Lagrangian using type-II…

High Energy Physics - Phenomenology · Physics 2022-07-13 Joy Ganguly

Several topics on CP violation in the lepton sector are reviewed. A few theoretical aspects concerning neutrino masses, leptonic mixing, and CP violation will be covered, with special emphasis on seesaw models. A discussion is provided on…

High Energy Physics - Phenomenology · Physics 2015-06-03 G. C. Branco , R. Gonzalez Felipe , F. R. Joaquim

The necessity of the fourth family follows from the SM basics. According to flavor democracy the Dirac masses of the fourth SM family fermions are almost equal with preferable value 450 GeV, which corresponds to common (for all fundamental…

High Energy Physics - Phenomenology · Physics 2014-11-18 S. Sultansoy

The fourth generation can give the correct trend of S_{phi K^0}, S_{pi^0 K^0} < sin2phi_1/beta, as indicated by data, and the effect, being largely leading order, is robust against hadronic uncertainties. The effect on S_{eta' K^0},…

High Energy Physics - Phenomenology · Physics 2009-11-11 Wei-Shu Hou , Makiko Nagashima , Guy Raz , Andrea Soddu

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

Decays of the kind $B_s\to D_s^{\pm}K^\mp, D_s^{\ast\pm}K^\mp, ...$ and $B_d\to D^{\pm}\pi^\mp, D^{\ast\pm}\pi^\mp, ...$ allow us to probe $\phi_s+\gamma$ and $\phi_d+\gamma$, respectively, involving the angle $\gamma$ of the unitarity…

High Energy Physics - Phenomenology · Physics 2010-04-05 Robert Fleischer

Top pair events provide a source of $b\bar{b}$ pairs, which can be used to probe CP violation in heavy-flavour mixing and decay. In events where one of the $W$ bosons decays leptonically to an electron or muon, the charge of the $W$ boson…

High Energy Physics - Experiment · Physics 2016-11-17 Jacob Julian Kempster

These lectures present the phenomenology of B meson decays and their impact on our understanding of CP violation in the quark sector, with an emphasis on measurements made at the e+e- B factories. Some of the relevant theoretical ideas such…

High Energy Physics - Experiment · Physics 2007-05-23 R. V. Kowalewski

We present a supersymmetric model of quark and lepton based on $S_4\times Z_3\times Z_4$ flavor symmetry. The $S_4$ symmetry is broken down to Klein four and $Z_3$ subgroups in the neutrino and the charged lepton sectors respectively.…

High Energy Physics - Phenomenology · Physics 2009-12-04 Gui-Jun Ding

In the Standard Model, three discovered generations of leptons and quarks are known to date. However, speculations about existence of next generations have a strong foothold. In this study, we sequentially extrapolate the Standard Model to…

High Energy Physics - Phenomenology · Physics 2025-10-30 Ramkrishna Joshi , Riddhiman Roy

After the Higgs discovery, the LHC has been looking for new resonances, decaying into pairs of Standard Model (SM) particles. Recently, the CMS experiment observed an excess in the di-photon channel, with a di-photon invariant mass of about…

High Energy Physics - Phenomenology · Physics 2018-06-29 Da Liu , Jia Liu , Carlos E. M. Wagner , Xiao-Ping Wang

We analyse the CP problem in the context of a supersymmetric extension of the standard model with universal strength of Yukawa couplings. A salient feature of these models is that the CP phases are constrained to be very small by the…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. C. Branco , M. E. Gomez , S. Khalil , A. M. Teixeira

We systematically investigate general forms of mass matrices for three-generation up and down quarks, including asymmetrical ones in generation space. Viable zero matrix elements are explored which are compatible with the current…

High Energy Physics - Phenomenology · Physics 2009-11-11 Nobuhiro Uekusa , Atsushi Watanabe , Koichi Yoshioka

Most limits on the fourth generation heavy top quark (the t') are based on the assumed dominance of t' -> Wb, which is expected to be case in the minimal fourth generation framework with a single Higgs (the so called SM4). Here we show,…

High Energy Physics - Phenomenology · Physics 2015-06-05 Michael Geller , Shaouly Bar-Shalom , Gad Eilam

The observed hierarchy of the quark masses is interpreted as a signal for an underlying ``subnuclear democracy'' as the relevant symmetry of the quark mass terms. A simple breaking of the symmetry leads to a mixing between the second and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Harald Fritzsch

We investigate the $\epsilon^{\prime} /\epsilon$ for $K\to \pi\pi$ in a sequential fourth generation model. By giving the basic formulae for $\epsilon^{\prime}/\epsilon$ in this model, we analyze the numerical results which are dependent of…

High Energy Physics - Phenomenology · Physics 2019-08-17 Chao-Shang Huang , Wu-Jun Huo , Yue-Liang Wu

The special features of CP violation in the Standard Model are presented. The significance of measuring CP violation in B, K and D decays is explained. The predictions of the Standard Model for CP asymmetries in B decays are analyzed in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yosef Nir

Heavy neutral leptons are motivated by several extensions of the Standard Model and their presence induces modifications in the lepton mixing matrix, including new Dirac and Majorana CP violating phases. It has been recently shown that…

High Energy Physics - Phenomenology · Physics 2023-06-28 A. Abada , J. Kriewald , E. Pinsard , S. Rosauro-Alcaraz , A. M. Teixeira

Contributions to B - \bar B mixing from physics beyond the standard model may be detected from CP-violating asymmetries in B decays. There exists the possibility of large new contributions that cannot be detected by first generation…

High Energy Physics - Phenomenology · Physics 2009-10-31 Lincoln Wolfenstein

The observed pattern of neutrino mixing may be the result of a 2-3($ \mu- \tau$) symmetry in the leptonic sector. We consider a two Higgs doublet model with a 2-3 symmetry in the down type quark and the charged lepton sector. The breaking…

High Energy Physics - Phenomenology · Physics 2009-11-11 Alakabha Datta , Patrick J. O'Donnell