Related papers: Boson Gauge Couplings at LEP
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…
The exclusive two-photon production at the LHC of pairs of W and Z bosons provides a novel and unique test-ground for the electroweak gauge boson sector. In particular it offers, thanks to high gamma-gamma center-of-mass energies, large and…
The high-energy and high-luminosity data-taking campaigns of the LEP e^+e^- collider provided the four collaborations, ALEPH, DELPHI, L3 and OPAL, with about 50000 W-boson pairs and about a thousand singly-produced W bosons. This unique…
The capability of the NLC in the $\gamma e$ collider mode to probe the CP-conserving $\gamma WW$ and $\gamma ZZ$ anomalous couplings through the use of the polarization asymmetry is examined. When combined with other measurements, very…
The discovery of Higgs boson plays a crucial role in understanding the electroweak symmetry breaking sector. From now on, solving the dynamics of this sector needs precision measurements of the couplings of the Higgs boson to the standard…
Taking into account the constraints from LEP1 and lower energy experiments, we identify the seven $SU(2)\times U(1)$ gauge invariant purely bosonic $dim=6$ operators which provide a quite general description of how New Physics could reflect…
In this note, we give a definitive basis for the dimension-eight operators leading to quartic -- but no cubic -- interactions among electroweak gauge bosons. These are often called anomalous quartic gauge couplings, or aQGCs. We distinguish…
The $WW$ production is the primary channel to directly probe the triple gauge couplings. We analyze the $e^+ e^- \rightarrow W^+ W^-$ process at the proposed Circular Electron-Positron Collider (CEPC), and find that the anomalous triple…
We briefly discuss the first direct experimental evidence from LEP2 on non-vanishing trilinear couplings among the weak vector bosons. Subsequently we review the improved Born approximation to include radiative corrections. Provided the…
The prime goal of this thesis is to study anomalous gauge boson self couplings, triple gauge boson couplings in particular, with the help of spin polarization observables of the gauge bosons $Z$ and $W^\pm$ in the presence of beam…
Direct measurements of the trilinear gauge boson couplings by the CDF and D0 collaborations at Fermilab are reviewed. Limits on the anomalous couplings were obtained at a 95 % CL from four diboson production processes: W-gamma production…
We consider the gauge-boson sector of a locally SU(2) x U(1) invariant effective Lagrangian with ten dimension-six operators added to the Lagrangian of the Standard Model. These operators induce anomalous three- and four-gauge-boson…
Electroweak boson scattering at the LHC provides a crucial avenue for probing physics beyond the Standard Model, particularly regarding deviations in quartic gauge couplings. We derive the complete set of positivity bounds for the $22$…
We study the anomalous triple gauge boson couplings (aTGC) in $ZW^\pm$ production in $3l$ + missing $E_T$ channel at the LHC for $\sqrt{s}=13$ TeV. We use cross sections, azimuthal asymmetry, forward-backward asymmetry, and polarization…
A data sample corresponding to an integrated luminosity of 232pb^-1 was collected in 1997 and 1998 by the L3 experiment at LEP in e+e- collisions at centre-of-mass energies between 181.7GeV and 188.7GeV. Pair production of fermions and…
We carry a systematic study of possible extensions of the standard model based on the gauge group SU(3)_c X SU(4)_L X U(1)_X. We consider both models with particles with exotic electric charges and models which do not contain exotic…
The anomalous $ZZ\gamma$ and $Z\gamma\gamma$ neutral triple gauge couplings occurred by dimension-eight operators are investigated through the process $\mu^+\mu^-\,\rightarrow\,\mu^+\gamma^*\mu^-\,\rightarrow\,\mu^+ Z(\nu\bar{\nu})\mu^-$ at…
We propose to probe the electroweak symmetry breaking sector by measuring the effective couplings of the top quark to gauge bosons. Using precision LEP data, we constrain the non--universal couplings of t-t-Z and t-b-W, parameterized by…
We search for anomalous trilinear gauge couplings in the ZZgamma and Zgammagamma vertices using data collected with the L3 detector at LEP at a centre-of-mass energy \sqrt{s}=189 GeV. No evidence is found and limits on these couplings and…
The data taken by DELPHI at centre-of-mass energies between 189 and 209 GeV are used to place limits on the CP-conserving trilinear gauge boson couplings Delta_g1z, lambda_gamma and Delta_kappag associated to W+W- and single W production at…