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Related papers: Extra Quarks and Bileptons in BSM Physics in a $33…

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We calculate a number of observables related to particle-antiparticle mixing and the branching ratios for the most interesting rare and CP-violating K and B decays in the Standard Model (SM3) extended by a fourth generation of quarks and…

High Energy Physics - Phenomenology · Physics 2010-12-01 Andrzej J. Buras , Björn Duling , Thorsten Feldmann , Tillmann Heidsieck , Christoph Promberger , Stefan Recksiegel

331 models constitute an extension of the Standard Model (SM) obtained by enlarging the SM gauge group $SU(3)_\text{C}\times SU(2)_\text{L}\times U(1)_Y$ to the group $SU(3)_\text{C}\times SU(3)_\text{L}\times U(1)_X$. We investigate how a…

High Energy Physics - Phenomenology · Physics 2019-01-14 Sébastien Descotes-Genon , Marta Moscati , Giulia Ricciardi

We study a two-Higgs doublet model extended with an additional singlet scalar (2HDM+S), and provide a brief introduction to the model and its parameters. Constraints are applied to the parameter space of this model in order to accommodate a…

High Energy Physics - Phenomenology · Physics 2019-09-25 Stefan von Buddenbrock , Alan S. Cornell , Elie D. R. Iarilala , Mukesh Kumar , Bruce Mellado , Xifeng Ruan , Esra Mohammed Shrif

We explore the low energy phenomenology of an F-theory based SU(5) model which, in addition to the known quarks and leptons, contains Standard Model singlets, and vector-like color triplets and SU(2) doublets. Depending on their masses and…

High Energy Physics - Phenomenology · Physics 2017-09-27 George K. Leontaris , Qaisar Shafi

Many models of physics beyond the Standard Model (SM) contain enhanced couplings to third generation particles. The predicted signatures include vector-like quarks and $t\bar{t}$ resonances. We present a review of non-SUSY based searches…

High Energy Physics - Experiment · Physics 2018-03-19 Mareike Meyer

We investigate the experimentally allowed parameter space of an extension of the standard model (SM3) by one additional family of fermions. Therefore we extend our previous study of the CKM like mixing constraints of a fourth generation of…

High Energy Physics - Phenomenology · Physics 2010-12-13 Otto Eberhardt , Alexander Lenz , Jürgen Rohrwild

We studied the signatures at the LHC of the electroweak SU(2) lepton doublet which embeds a doubly charged lepton. The doubly charged lepton pair and single production rates, which are different from the triplet case, are studied and all…

High Energy Physics - Phenomenology · Physics 2014-06-11 Teng Ma , Bin Zhang , Giacomo Cacciapaglia

The production and decay of exotic leptons are discussed in the context of the vector singlet, vector doublet and fer\-mion mirror-fer\-mion models, at c.m. energies $\sqrt{s}=190GeV$ (LEP II) and $\sqrt{s}=500GeV$ (NLC). The model…

High Energy Physics - Phenomenology · Physics 2009-09-25 F. M. L. Almeida , J. H. Lopes , J. A. Martins Simões , P. P. Queiroz Filho , A. J. Ramalho

Motivated by the $R_K$ and $R_{K^*}$ anomalies from B decays, we extend the minimal supersymmetric model with a non-universal anomaly-free $U(1)^\prime$ gauge symmetry, coupling non-universally to the lepton sector as well as the quark…

High Energy Physics - Phenomenology · Physics 2018-12-12 Guang Hua Duan , Xiang Fan , Mariana Frank , Chengcheng Han , Jin Min Yang

Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons, leading to multiple photon-induced processes. This proceeding presents searches for physics beyond the Standard Model enabled by photon-photon…

High Energy Physics - Experiment · Physics 2023-07-17 Klaudia Maj

We develop a ${\rm SU}(3)_C\otimes {\rm SU}(3)_L\otimes {\rm U}(1)_X$ model where the number of fermion generations is fixed by cancellation of gauge anomalies, being a type of 3-3-1 model with new charged leptons. Similarly to the…

High Energy Physics - Phenomenology · Physics 2018-04-04 E. R. Barreto , A. G. Dias , J. Leite , C. C. Nishi , R. L. N. Oliveira , W. C. Vieira

The Standard Model has three generations of fermions and although it does not contain any explicit reason for this, the existence of additional generations is now very constrained by experiment. Present measurements are saturating…

High Energy Physics - Phenomenology · Physics 2014-12-17 Alfredo Aranda , Jose A. R. Cembranos

The rare decays {$B^- \to \tau \bar\nu$}, \mbox{$B \to \tau^+ \tau^-$}, {$b \to X \nu \bar\nu$} and \mbox{$b \to X \tau^+ \tau^-$} all contain third generation leptons in the final state, and hence are sensitive to new physics that couples…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dafne Guetta , Enrico Nardi

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

We establish some signatures of the extra bilepton boson ${X^0}$ predicted in the ${SU (3)_C \times SU (3)_L \times U (1)_X}$ model with right-handed neutrinos. We analyze the process $p + p \longrightarrow X^0 +X^{0*} + {\hbox…

High Energy Physics - Phenomenology · Physics 2008-10-15 E. Ramirez Barreto , Y. A. Coutinho , J. Sa Borges

We show that it is possible to implement soft superweak CP violation in the context of a 331 model with only three triplets. All CP violation effects come from the exchange of singly and doubly charged scalars. We consider the implication…

High Energy Physics - Phenomenology · Physics 2016-09-06 J. C. Montero , V. Pleitez , O. Ravinez

We investigate the leading effects of extending the Standard Model of electroweak interactions by an extra iso-singlet up- and down- type quark pair on various distributions and total branching ratio of the inclusive B-> X_s l^+ l^- (l…

High Energy Physics - Phenomenology · Physics 2014-11-17 Mohammad R. Ahmady , Makiko Nagashima , Akio Sugamoto

If new leptons exist close to the electroweak scale, they can be produced in pairs at LHC through standard or new interactions. We study the production of heavy lepton pairs in SM extensions with: (i) a Majorana or Dirac lepton triplet, as…

High Energy Physics - Phenomenology · Physics 2009-12-22 J. A. Aguilar-Saavedra

We investigate the sensitivity of top pair production to the properties of different Beyond the Standard Model theories embedding a new neutral boson. We include six-fermion decay, and account for the full tree-level Standard Model ttbar…

High Energy Physics - Phenomenology · Physics 2016-12-12 Lucio Cerrito , Declan Millar , Stefano Moretti , Francesco Spanò

We propose an extension of the standard model with an extra U(1)' abelian symmetry, three Higgs doublets and one Higgs singlet, where the new U(1)' charges are flavour non-universal. As a result, the model introduces an enlarger particle…

High Energy Physics - Phenomenology · Physics 2018-08-29 R. Martinez , F. Ochoa , J. M. Quimbayo