Related papers: Unitarity Constraints on Dimension-Six Operators
We study non-standard top quark couplings in the effective field theory approach. All nine dimension-six operators that generate anomalous couplings between the electroweak gauge bosons and the third-generation quarks are included. We…
On the verge of conclusive checks on the Standard Model by the LHC, we discuss some of the basic assumptions. The reason for this analysis stems from a recent proposal of an Electroweak Model based on a nonlinearly realized gauge group…
Triggering the electroweak symmetry breaking may not be the only key role played by the Higgs boson in particle physics. In a recently proposed warped five-dimensional $SO(5)\otimes U(1)$ gauge-Higgs unification model the Higgs boson can…
In this paper we express the effect of new physics on gauge boson self energy corrections through non-renormalizable dimension six operators. Using the precision electroweak data we then determine a lower bound on the scale ${\l}$…
We consider modifications of the Higgs potential due to new physics at high energy scales. These upset delicate cancellations predicted by the Standard Model for processes involving Higgs bosons and longitudinal gauge bosons, and lead to a…
We set constraints on the trilinear Higgs boson self-coupling, $\lambda_3$, by combining the information coming from the $W$ mass and leptonic effective Weinberg angle, electroweak precision observables, with the single Higgs boson analyses…
We derive bounds on Higgs and gauge--boson anomalous interactions using the CDF data for the process $p \bar{p} \to \gamma\gamma\gamma + X$. We use a linearly realized $SU_L(2) \times U_Y(1)$ invariant effective Lagrangian to describe the…
We compute a unitarity bound for higgs mass using one--loop corrected s--wave partial amplitude for $Z_L Z_L \rightarrow Z_L Z_L$ scattering. We use the equivalence theorem and show that the higgs mass has to be less than $\approx 600$ GeV…
Tree-level unitarity constraints on the masses of the Higgs bosons in the general Two Higgs Doublet Model (THDM) are studied. We first consider the case where the Higgs potential is invariant under a discrete symmetry transformation, and…
The effective Lagrangian formalism provides a way to study the new physics effects at the electroweak scale. We study the Higgs pair production via the vector-boson fusion (VBF) at the Large Hadron Collider within the framework of the…
Weak vector boson scattering (VBS) is a sensitive probe of new physics effects in the electroweak symmetry breaking. Currently, experimental results at the LHC are interpreted in the effective field theory approach, where possible…
The quartic Higgs-gauge-boson coupling $g_{hhWW}$ is sensitive to the electroweak symmetry breaking mechanism, however, it is challenging to be measured at the large hadron collider. We show that the coupling can be well probed at future…
We investigate unitarity of $W^+W^-$ scattering in the context of theory space models of the form $U(1)\times {[SU(2)]}^N\times SU(2)_{N+1}$, which are broken down to $U(1)_{EM}$ by non-linear $\Sigma$ fields, without the presence of a…
We compute the energy scales of perturbative unitarity violation in various $2 \to 4$ vector boson scattering (VBS) processes and compare them to lower multiplicity processes. The final states include $h^4$, $V_L V_L h h$, and $V_L^4$,…
We study scattering of the electroweak gauge bosons in 5D warped models. Within two different models we determine the precise manner in which the Higgs boson and the vector resonances ensure the unitarity of longitudinal vector boson…
We reconsider the constraints on Universal Extra Dimensions (UED) models arising from precision electroweak data. We take into account the subleading contributions from new physics (expressed in terms of the X,Y ... variables), as well as…
We explore the sensitivity of future muon colliders to CP-violating interactions in the Higgs sector, specifically focusing on the process $\mu^- \mu^+ \to h \bar{\nu_{l}} \nu_{l} \to b\bar{b} \bar{\nu_{l}}\nu_{l}$. Using a…
The triviality and vacuum stability bounds on the Higgs-boson mass were revisited in presence of weakly-coupled new interactions parameterized in a model-independent way by effective operators of dimension 6. It was shown that for the scale…
In five dimensional models of Higgsless electroweak symmetry breaking, tree level unitarity in gauge boson scattering is restored by the exchange of gauge boson Kaluza-Klein modes instead of a Higgs boson. Unitarity of scattering amplitudes…
We derive the causality and unitarity constraints on dimension 6 and dimension 8 Gluon field strength operators in the Standard Model Effective Field Theory (SMEFT). In the first part of the paper, we use the 'amplitude analysis' i.e.…