Related papers: Exotic Quarks in Twin Higgs Models
New almost-degenerate charged and neutral heavy leptons are a feature of a number of theories of physics beyond the Standard Model. The prospects for detecting these at the Large Hadron Collider using a time-of-flight technique are…
Many new-physics models, especially those with a color-triplet top-quark partner, contain a heavy color-octet state. The "naturalness" argument for a light Higgs boson requires that the color-octet state be not much heavier than a TeV, and…
Standard theories of electroweak interactions are based on the concept of a gauge symmetry broken by the Higgs mechanism. If they are placed in an environment with a sufficiently high temperature, the symmetry gets restored. It turns out…
We extend the fraternal twin Higgs scenario to include a novel dark matter candidate as well as a mechanism for generating a matter/antimatter asymmetry in both sectors. A spontaneous breaking of twin color results in quark degrees of…
We consider a scenario of a composite Higgs arising from a strong sector. We assume that the lowest lying composite states are the Higgs scalar doublet and a massive vector triplet, whose dynamics below the compositeness scale are described…
A study of two-Higgs-doublet models (2HDM) in the decoupling limit reveals the existence of parameter configurations with a large triple-Higgs self-coupling as the only low-energy trace of a departure from a Standard Model (SM) Higgs…
Precise measurements of the properties of the top quark test the Standard Model (SM) and can be used to constrain new physics models. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the SM,…
A search is performed for electroweak production of a vector-like top quark partner T of charge 2/3 in association with a standard model top or bottom quark, using 2.3 inverse femtobarns of proton-proton collision data at sqrt(s) = 13 TeV…
A large enhancement of a factor of 1.5 - 2 in Higgs production and decay in the diphoton channel, with little deviation in the ZZ channel, can only plausibly arise from a loop of new charged particles with large couplings to the Higgs. We…
Using a four fermion interaction Lagrangian, we demonstrate that the spontaneous breaking of vector symmetries requires the existence of a light (comparing with the heavy fermion mass) scalar particle and the low energy effective theory…
In this paper, we construct an effective model that describes the electroweak symmetry breaking sector by means of composite Higgs-like scalars, following the ideas of Minimal Walking Technicolor (MWT). We argue that, because of the general…
A search for exotic decays of the Higgs boson (H) with a mass of 125 GeV to a pair of light pseudoscalars $\mathrm{a}_1$ is performed in final states where one pseudoscalar decays to two b quarks and the other to a pair of muons or $\tau$…
We find the exchange symmetry between left and right handed top quark in composite Higgs model with partial compositeness is efficient to soften the Higgs potential and reduce fine tuning. This symmetry can keep the Higgs potential in top…
If electroweak symmetry breaking arises via strong dynamics, electroweak precision tests and flavour physics experiments suggest that the minimal model should closely resemble the Standard Model at the LHC. I describe two directions going…
In this thesis, we discuss theoretical properties of various Higgs sectors, and we analyze constraints from current experimental data, and then we study collider signatures in each Higgs sector. In Part I, we focus on the phenomenology of…
This paper reviews some of the most recent results from the CDF and DZERO experiments on the searches for Standard Model and Non-Standard Model Higgs bosons, and other new phenomena at the Tevatron. Both experiments examine data from proton…
We present the result of a search for charged Higgs decays of the top quark, produced in $p\bar{p}$ collisions at $\surd s =$ 1.8 TeV. When the charged Higgs is heavy and decays to a tau lepton, which subsequently decays hadronically, the…
We know there is new physics at the electroweak scale, but we don't know what it is. Right now, the top quark is our only window on to this physics. In almost all models of electroweak symmetry breaking, top either couples strongly to new…
We calculate the oblique electroweak corrections and confront them with the experiments in a composite Higgs version of the standard model. A vector-like weak doublet and a singlet fermion are added to the standard model without elementary…
Heavy vector-like quarks (VLQs) appear in many models of beyond the Standard Model physics. Direct experimental searches require these new quarks to be heavy, $\gsim$ 800-1000 GeV. We perform a global fit of the parameters of simple VLQ…