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Related papers: Fourth Lepton Family is Natural in Technicolor

200 papers

Condensates of colored fermions driving electroweak symmetry breaking could give rise to a light pseudoscalar that would show up in the Higgs search at the LHC. The branching ratios of its decay will distinguish it from the Higgs and…

High Energy Physics - Phenomenology · Physics 2012-03-07 B. Holdom

We demonstrate that the inclusion of a realistic lepton sector can relax significantly the upper bound on top partner masses in minimal composite Higgs models, induced by the lightness of the Higgs boson. To that extend, we present a…

High Energy Physics - Phenomenology · Physics 2015-05-13 Adrian Carmona , Florian Goertz

We provide a complete extension of Minimal Walking Technicolor able to account for the standard model fermion masses. The model is supersymmetric at energies greater or equal to the technicolor compositeness scale. We integrate out, at the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Matti Antola , Stefano Di Chiara , Francesco Sannino , Kimmo Tuominen

Composite Higgs models provide a natural, non-supersymmetric solution to the hierarchy problem. In these models, one or more sets of heavy top-partners are typically introduced. Some of these new quarks can be relatively light, with a mass…

High Energy Physics - Phenomenology · Physics 2014-11-21 Guenther Dissertori , Elisabetta Furlan , Filip Moortgat , Pascal Nef

As the Higgs boson properties settle, the constraints on the Standard Model extensions tighten. We consider all possible new fermions that can couple to the Higgs, inspecting sets of up to four chiral multiplets. We confront them with…

High Energy Physics - Phenomenology · Physics 2016-02-17 Nicolas Bizot , Michele Frigerio

The nonbaryonic dark matter of the Universe can consist of new stable charged species, bound in heavy neutral "atoms" by ordinary Coulomb interaction. Stable $\bar U$ (anti-$U$)quarks of 4th generation, bound in stable colorless ($\bar U…

High Energy Physics - Phenomenology · Physics 2014-02-04 M. Yu. Khlopov , R. M. Shibaev

We consider large classes of chiral extensions of the Standard Model, including new quark generations that do not involve additional neutrinos as well as lepton generations without quarks. An analysis of renormalization flows of Yukawa and…

High Energy Physics - Phenomenology · Physics 2015-05-28 Alexander Knochel , Christof Wetterich

Very little is known about the mass spectrum of fermions in the standard model. In this talk, I point out that in the simplest extension of the standard model, in which all right-handed fields are singlets, it is quite possible that a…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marc Sher

A natural, non-supersymmetric solution to the hierarchy problem generically requires fermionic partners of the top quark with masses not much heavier than 500 GeV. We study the pair production and detection at the LHC of the top partners…

High Energy Physics - Phenomenology · Physics 2010-03-03 Roberto Contino , Geraldine Servant

We investigate the phenomenology of minimal four-family MSSM supergravity theories containing an additional generation of heavy fermions along with their superpartners. We demand: gauge coupling constant unification at high energy scales;…

High Energy Physics - Phenomenology · Physics 2011-01-27 J. F. Gunion , Douglas W. McKay , H. Pois

A new mechanism is presented for the generation of quark and lepton masses, based on a heavy fourth family and a new sector of massless fermions. The massless fermions have only discrete chiral symmetries and they are confined by the…

High Energy Physics - Phenomenology · Physics 2009-10-22 B. Holdom

We explore a scenarios where topcolor-like dynamics operates in the presence of fourth generation matter fields. Using the Minimal Walking Technicolor as a concrete basis for model building, we construct explicit models and confront them…

High Energy Physics - Phenomenology · Physics 2011-02-08 Hidenori S. Fukano , Kimmo Tuominen

It is a challenge to explain why neutrinos are so light compared to other leptons. Small neutrino masses can be explained if right-handed fermions propagate in large extra dimensions. Fermions propagating in the bulk would have implications…

High Energy Physics - Phenomenology · Physics 2009-11-30 Douglas M. Gingrich

We consider the possibility that a massive fourth family neutrino, predicted by a recently proposed minimal technicolor theory, could be the source of the dark matter in the universe. The model has two techniflavors in the adjoint…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kimmo Kainulainen , Kimmo Tuominen , Jussi Virkajarvi

We investigate the possibility of a fourth sequential generation in the lepton sector. Assuming neutrinos to be Majorana particles and starting from a recent - albeit weak - evidence for a non-zero admixture of a fourth generation neutrino…

High Energy Physics - Phenomenology · Physics 2012-05-03 Alexander Lenz , Heinrich Päs , Dario Schalla

We evaluate the LHC discovery potential for the fourth family Standard Model neutrinos in the process $pp\to Z/h\to\nu_{4}{\bar{\nu}_{4}}\to W\mu W\mu$. We show that, depending on their masses, the simultaneous discovery of both the Higgs…

High Energy Physics - Phenomenology · Physics 2009-01-06 T. Cuhadar-Donszelmann , M. Karagoz Unel , V. E. Ozcan , S. Sultansoy , G. Unel

We propose a channel for the possible discovery of new charged leptons at the Large Hadron Collider. The proposed final state contains three same-sign leptons, making this new channel practically back- groundless. The method is illustrated…

High Energy Physics - Experiment · Physics 2010-05-12 V. E. Ozcan , S. Sultansoy , G. Unel

Recently proposed Little Higgs models present a viable solution to the naturalness problem of the Standard Model. An additional discrete symmetry, called T-parity, has been included in the simplest Little Higgs models to evade the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Debajyoti Choudhury , Dilip Kumar Ghosh

If the standard model of quarks and leptons is extended to include three singlet right-handed neutrinos, then the resulting fermion structure admits an infinite number of anomaly-free solutions with just one simple constraint. Well-known…

High Energy Physics - Phenomenology · Physics 2017-01-18 Corey Kownacki , Ernest Ma , Nicholas Pollard , Mohammadreza Zakeri

The spin-charge-family theory, proposed by the author as a possible new way to explain the assumptions of the standard model, predicts at the low energy regime two decoupled groups of four families of quarks and leptons. In two successive…

High Energy Physics - Phenomenology · Physics 2013-07-10 Norma Susana Mankoc Borstnik