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Related papers: Precision Constraints on Extra Fermion Generations

200 papers

Apart from offering explanations not only for the distinctive fermion mass and mixing patterns but also for the actual values of the mass and mixing parameters, the dual colour solution to the generation puzzle gives numerous detailed…

High Energy Physics - Phenomenology · Physics 2007-05-23 HM Chan

This paper studies models with extended electroweak gauge sectors of the form SU(2) x SU(2) x U(1) x [SU(2) or U(1)]. We establish the general behavior of corrections to precision electroweak observables in this class of theories and…

High Energy Physics - Phenomenology · Physics 2016-09-06 R. S. Chivukula , H. -J. He , J. Howard , E. H. Simmons

There have been a great deal of works on the precision test of the standard model (SM) because of the incredibly precise data obtained at the LEP and the new measurements of $M_W$ and $m_t$ at the Fermilab Tevatron as well as the recent…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kyungsik Kang , Sin Kyu Kang

The Born approximation, based on $\bar\alpha \equiv\alpha (m_Z)$ instead of $\alpha$, reproduces all electroweak precision measurements within their $(1\sigma)$ accuracy. The low upper limits for the genuinely electroweak corrections…

High Energy Physics - Phenomenology · Physics 2015-06-25 V. A. Novikov , L. B. Okun , M. I. Vysotsky

We argue that in dynamical models of fermion masses, which explain the three mass scales of the generations of fermions with three separate heavy scales above the electroweak symmetry breaking scale, the off diagonal CKM matrix elements…

High Energy Physics - Phenomenology · Physics 2009-09-25 Nick Evans

Extra spatial dimensions are proposed by recent theories that postulate the scale of gravity to be of the same order as the electroweak scale. A sizeable interaction between gravitons and Standard Model particles is then predicted. Effects…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

In 5 dimensions the electroweak symmetry can be broken by boundary conditions, leading to a new type of Higgsless theories. These could in principle improve on the 4D case by extending the perturbative domain to energies higher than $4 \pi…

High Energy Physics - Phenomenology · Physics 2008-11-26 Riccardo Barbieri , Alex Pomarol , Riccardo Rattazzi

We summarize the status of calculations of the electroweak radiative corrections to W and Z boson production via the Drell-Yan mechanism at hadron colliders. To fully exploit the precision physics potential of the high-luminosity…

High Energy Physics - Phenomenology · Physics 2009-11-07 U. Baur , D. Wackeroth

We review the current status of precision electroweak measurements and the constraints they impose on new physics. We perform a model independent analysis using the STU-formalism of Ref. 1, and then discuss how the Z-pole data from LEP and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tatsu Takeuchi , Will Loinaz , Aaron K. Grant

We explore the scenario in which the breaking of the electroweak symmetry is due to the simultaneous presence and interplay of a dynamical sector and an unnatural elementary Higgs. We introduce a low energy effective Lagrangian and…

High Energy Physics - Phenomenology · Physics 2014-11-20 M. Antola , M. Heikinheimo , F. Sannino , K. Tuominen

The status of precision calculations for the processes e+e- --> WW --> 4 fermions is reviewed, paying particular attention to questions of gauge invariance and recent progress concerning photonic radiative corrections.

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Dittmaier

This paper studies the electroweak production of all possible four fermion states in e+ e- collisions. Since the methods employed to evaluate the complete matrix elements and phase space are very general, all four fermion final states in…

High Energy Physics - Phenomenology · Physics 2009-10-28 F. A. Berends , R. Kleiss , R. Pittau

We present a new scenario for the baryon number violation that may take place in models with large extra dimensions. Our idea is interesting because leptogenesis with a low reheating temperature requires an alternative source of the B+L…

High Energy Physics - Phenomenology · Physics 2009-11-07 Tomohiro Matsuda

Conventional scenarios of electroweak (EW) baryogenesis are strongly constrained by experimental searches for CP violation beyond the SM. We propose an alternative scenario where the EW phase transition and baryogenesis occur at…

High Energy Physics - Phenomenology · Physics 2019-05-01 Alfredo Glioti , Riccardo Rattazzi , Luca Vecchi

We study the physics of spontaneously broken family symmetries acting on the third generation. Massless familons (or Majorons) $f$ associated with such broken symmetries are motivated especially by cosmological scenarios with decaying tau…

High Energy Physics - Phenomenology · Physics 2016-08-25 Jonathan L. Feng , Takeo Moroi , Hitoshi Murayama , Erhard Schnapka

We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may…

High Energy Physics - Phenomenology · Physics 2009-11-07 Thomas Appelquist , Bogdan A. Dobrescu , Adam R. Hopper

It now seems plausible that the observed baryon asymmetry may have been produced at the electroweak phase transition. We review the considerations which lead to this conclusion, focusing on the obstacles to making reliable estimates. These…

High Energy Physics - Phenomenology · Physics 2008-02-03 Michael Dine

A brief review of the recent developments in the physics from extra dimensions is given with a focus on the effects of Kaluza-Klein excitations in the Standard Model sector. It is shown that the current accurate data on the Fermi constant…

High Energy Physics - Phenomenology · Physics 2014-11-17 Pran Nath

We discuss electroweak constraints on TeV scale extensions of the standard model. To obtain model-independent results, effective theory approach is adopted. Constraints are given on arbitrary linear combinations of a set of dimension-6…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhenyu Han

We review the recent discussion in the literature of one family extended technicolour models with techni-fermion mass spectra compatible with the experimental data for the precision parameters S,T,U,V, W and X and ETC interactions…

High Energy Physics - Phenomenology · Physics 2010-11-01 Nick Evans