Related papers: Top couplings and top partners
We discuss associated production of a Higgs boson with a pair of $t {\bar t}$ quarks at a future high energy $e^+e^-$ collider. The process $e^+e^-\to t {\bar t}h$ is particularly sensitive to the presence of new physics and we consider the…
An SU(2) vectorlike singlet quark with a charge either +2/3 (t') or -1/3 (b') is predicted in many extensions of the Standard Model. The mixing of these quarks with the top or bottom lead to Flavor Changing Yukawa Interactions and Neutral…
The recent ATLAS and CMS experiments show the first observations of a new particle in the search for the Standard Model Higgs boson at the LHC. We revisit the scenario that high-dimensional operators of fermions must be present due to the…
If a TeV-scale charged gauge boson (W') is discovered at the Large Hadron Collider (LHC), it will become imperative to determine its chiral couplings to standard model (SM) fermions in order to learn about the underlying theory containing…
Inclusive Standard Model Higgs boson pair production and subsequent decay to same-sign dileptons via weak gauge W bosons at the CERN Large Hadron Collider has the capability to determine the Higgs boson self-coupling, lambda. The large top…
We study methods of extracting new physics signals in final states with a top-quark pair plus large missing energy at the LHC. We consider two typical examples of such new physics: pair production of a fermionic top partner (a $T'$ in…
The strength of the Yukawa coupling of the leptons and quarks with the Higgs boson is uniquely determined by the Higgs mechanism for generating masses in the Standard Model. The top-Higgs coupling can be measured directly in the process…
We obtain constraints on the mixing of vector-like quarks coupling predominantly to the third generation. We consider all (seven) relevant types of vector-like quarks, individually. The constraints are derived from oblique corrections and Z…
It now appears phenomenologically that the third family of fundamental fermions may be essentially different fron the first two. Particularly the high value (174GeV?) of the top quark mass suggests a special role. In the standard model all…
New vectorlike quarks are predicted in many new physics scenarios beyond the Standard Model~(SM) and could potentially be discovered at the LHC. Based on a simplified model including a singlet vectorlike top partner with charge $2/3$, we…
Collisions of particles at the energy frontier can reveal new particles and forces via localized excesses. However, the initial observation may be consistent with a large variety of theoretical models, especially in sectors with new top…
We investigate the production of Higgs particles in association with the supersymmetric scalar partners of the top quark at proton colliders. In the minimal supersymmetric extension of the Standard Model, the cross sections for the…
In this paper, we examine the interactions of the top quarks with the $Z$ boson using the top quark pair production associated with neutrino pair ($t\bar{t}\nu_{l}\bar{\nu_{l}}$) at the LHC. In particular, potential constraints on the…
We consider a theory with composite top quarks but an elementary Higgs boson. The hierarchy problem can be solved by supplementing TeV scale top compositeness with either supersymmetry or Higgs compositeness appearing at the multi-TeV…
The search and the probe of the fundamental properties of Higgs boson(s) and, in particular, the determination of their charge conjugation and parity (CP) quantum numbers, is one of the main tasks of future high-energy colliders. We…
The experiments at the LHC are searching for many different final states that can hint to the presence of new physics beyond the Standard Model. One of the most interesting and promising sectors for these searches is that of the top quark,…
Cai, Cheng, and Terning suggested a model in which the left-handed top quark is identified with a gaugino of an extended gauge group, and its superpartner is a spin-1 particle. We perform a phenomenological analysis of this model, with a…
We discuss the phenomenology of many Higgs doublet model - the model where each Higgs isodoublet couples with each own quark and lepton with relatively big Yukawa coupling constants. Namely, we discuss the discovery potential of the Higgs…
In most extensions of the Standard Model, heavy charged Higgs bosons at the LHC are dominantly produced in association with heavy quarks. An up-to-date determination of the next-to-leading order total cross section in a type-II…
We study the phenomenology of new heavy vector-like fermions that couple to the third generation quarks via Yukawa interactions, covering all the allowed representations under the standard model gauge groups. We first review tree and loop…