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Related papers: A 4th generation scenario

200 papers

A four generation supersymmetric model is proposed, in which the Tevatron ``top-quark'' events are reinterpreted as the production of $t^\prime$ which decays dominantly to $bW^+$. In this model, $m_t\simeq m_W$, and $t\rta\widetilde…

High Energy Physics - Phenomenology · Physics 2007-05-23 Howard E. Haber

While SUSY particles, if they exist at the TeV-scale, will be discovered at the Tevatron or the LHC, the determination of the SUSY-breaking scenario and its free parameters will require additional information, e.g. from a future…

High Energy Physics - Phenomenology · Physics 2010-11-19 M. Klasen

Requirement that the vacuum expectation values of Higgs fields immediately after the phase transition be large enough imposes constraints upon the parameters of the minimal supersymmetric model. In particular, one obtains the upper bound on…

High Energy Physics - Phenomenology · Physics 2009-10-22 Stanley Myint

We propose a new mechanism of TeV scale leptogenesis where the chemical potential of right-handed electron is passed on to the $B-L$ asymmetry of the Universe in the presence of sphalerons. The model has the virtue that the origin of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Narendra Sahu , Utpal Sarkar

Electroweak baryogenesis (EWBG) remains a theoretically attractive and experimentally testable scenario for explaining the cosmic baryon asymmetry. We review recent progress in computations of the baryon asymmetry within this framework and…

High Energy Physics - Phenomenology · Physics 2015-06-05 David E. Morrissey , Michael J. Ramsey-Musolf

We discuss the potential of combined LHC and ILC experiments for SUSY searches in a difficult region of the parameter space, in which all sfermion masses are above the TeV scale. Precision analyses of cross sections of light chargino…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Rolbiecki , K. Desch , J. Kalinowski , G. Moortgat-Pick

We revisit four generations within the context of supersymmetry. We compute the perturbativity limits for the fourth generation Yukawa couplings and show that if the masses of the fourth generation lie within reasonable limits of their…

High Energy Physics - Phenomenology · Physics 2010-03-19 Rohini M. Godbole , Sudhir K. Vempati , Akin Wingerter

We propose a UV completion of the inverse see-saw scenario using fermion SU(2) triplet representations. Within this framework, a variation of the standard thermal leptogenesis is achievable at the O(TeV) scale, owing to the presence of a…

High Energy Physics - Phenomenology · Physics 2013-03-14 Francois-Xavier Josse-Michaux , Emiliano Molinaro

Using firmly established experimental inputs such as epsilon_K, Delta M_d, Delta M_s, BR(B -> tau nu), gamma, V_cb along with corresponding lattice matrix elements which have been well studied and are in full QCD such as B_K, SU3 breaking…

High Energy Physics - Phenomenology · Physics 2015-05-27 Enrico Lunghi , Amarjiit Soni

Introducing heavy particles with strong couplings to the Higgs field can strengthen electroweak phase transition, through the entropy release mechanism from both bosons and fermions. We analyze the possibility of electroweak baryogenesis in…

High Energy Physics - Phenomenology · Physics 2014-03-07 Xue Chang , Ran Huo

Within the four generation Standard Model, the Higgs couplings to gluons and to photons deviate in a significant way from the predictions of the three generation Standard Model. As a consequence, large departures in several Higgs production…

High Energy Physics - Phenomenology · Physics 2016-11-26 Eric Kuflik , Yosef Nir , Tomer Volansky

We propose a new mechanism for generating small neutrino masses which predicts the relation m_\nu ~ v^4/M^3, where v is the electroweak scale, rather than the conventional seesaw formula m_\nu ~ v^2/M. Such a mass relation is obtained via…

High Energy Physics - Phenomenology · Physics 2009-10-29 K. S. Babu , S. Nandi , Zurab Tavartkiladze

We review that the heavy CP-even MSSM Higgs boson is still a viable candidate to explain the Higgs signal at 125 GeV. This is possible in a highly constrained parameter region, that will be probed by LHC searches for the CP-odd Higgs boson…

High Energy Physics - Phenomenology · Physics 2016-12-28 S. Heinemeyer

I present a general exclusion bound for the Higgs in fourth generation scenarios with a general lepton sector. Recent Higgs searches in fourth generation scenarios rule out the entire Higgs mass region between 120 and 600 GeV. That such a…

High Energy Physics - Phenomenology · Physics 2011-10-25 Linda M. Carpenter

In a model independent framework, the effects of new physics at the electroweak scale can be parametrized in terms of an effective Lagrangian expansion. Assuming the $SU(2)_L x U(1)_Y$ gauge symmetry is linearly realized, the expansion at…

High Energy Physics - Phenomenology · Physics 2014-11-21 J. Gonzalez-Fraile

If the fourth generation fermions exist, the new quarks could influence the branching ratio of the decay $B_s \to \nu \bar{\nu} \gamma$. We obtain two solutions of the fourth generation CKM factor $V^*_{t's} V_{t'b}$ from the decay of $B…

High Energy Physics - Phenomenology · Physics 2009-10-31 Yusuf Dincer

We present a simple solution to the little hierarchy problem in the MSSM: a vector-like fourth generation. With O(1) Yukawa couplings for the new quarks, the Higgs mass can naturally be above 114 GeV. Unlike a chiral fourth generation, a…

High Energy Physics - Phenomenology · Physics 2014-11-20 Peter W. Graham , Ahmed Ismail , Surjeet Rajendran , Prashant Saraswat

We propose six new benchmark scenarios for Higgs boson searches in the Minimal Supersymmetric Standard Model. Our calculations follow the recommendations of the LHC Higgs Cross Section Working Group, and benefit from recent developments in…

Recent developments on the four dimensional (4d) lattice studies of the finite temperature electroweak phase transition (EWPT) are summarized. The phase diagram is given in the continuum limit. The finite temperature SU(2)-Higgs phase…

High Energy Physics - Lattice · Physics 2015-06-25 Z. Fodor

We explore the connection between the strength of the electroweak phase transition and the properties of the Higgs boson. Our interest is in regions of parameter space that can realize electroweak baryogenesis. We do so in a simplified…

High Energy Physics - Phenomenology · Physics 2013-05-30 Timothy Cohen , David E. Morrissey , Aaron Pierce