相关论文: Model-Independent Z' Constraints from Measurements…
Model independent constraints on the mass of extra neutral gauge bosons and their couplings to charged leptons are given for LEP~II and a 500\,GeV $e^+e^-$ collider. Analytical exclusion limits are derived in the Born approximation. The…
Model independent constraints on the mass of an extra neutral gauge boson and its couplings to charged leptons are given for the $e^-e^-$ option of a future linear collider. Analytic exclusion limits are derived in the Born approximation.…
Constraints on extra neutral gauge bosons are obtained from $e^+e^-\rightarrow f\bar f$ at NLC energies. Model independent limits on the $Z'f\bar f$ couplings and lower limits on the $Z'$ mass are discussed. Typical GUTs with $M_{Z'}$ up to…
Many models beyond the Standard Electroweak Theory, top-down or bottom-up, contain extensions of the gauge symmetry group by extra U(1)' factors which can be understood or treated as subgroups of E(6). A brief overview of such models is…
The phenomenological constraints on extra neutral gauge bosons at present and at future colliders are reviewed. Special attention is paid to the influence of radiative corrections, systematic errors, and kinematic cuts on the Z'…
We examine the decay of $Z_1$ in electrons with recent data from LEP. The partial width $\Gamma(Z_1\to e^-e^+)$ is studied in the framework of a left-right symmetric model with standard electroweak corrections. Processes measured near the…
We explore the possibility of deriving model independent limits on the anomalous trilinear electroweak gauge boson couplings from high energy $e^+e^-\to W^+W^-$, by combining the cross sections for the different initial and final states…
Extra neutral gauge bosons arise in many extensions of the Standard Model. If one were to be discovered it would be necessary to measure its properties so that we could understand its origins. In this report we find that Z' couplings can be…
We study how the recent experimental results constrain the gauge sectors of U(1) extensions of the standard model using a novel representation of the parameter space. We determine the bounds on the mixing angle between the massive gauge…
We analyze various models with an extra U(1) gauge symmetry in addition to the Standard Model (SM) gauge group at low energies, and impose limits on the mass of the neutral Z' boson, M_Z', predicted in all such models, and on the Z-Z'…
We discuss electroweak precision constraints on dimension-6 operators in the effective theory beyond the standard model. We identify the combinations of these operators that are constrained by the pole observables (the W and Z masses and…
We investigate the effects of extra neutral gauge bosons on the high $Q^2$ region of the $e^+p \to e^+ X$ cross section at $\sqrt{s}=300$ GeV. We found that the only models with electroweak strength coupling, typical of extended gauge…
In a truly model-independent approach, we reexamine a minimal extension of the Standard Model (SM) through the introduction of an additional $U(1)$ symmetry leading to a new neutral gauge boson ($Z'$), allowing its kinetic mixing with the…
We tested several models in which the Standard Model (SM) gauge group is extended by an additional U(1) gauge symmetry, against available electroweak precision data to impose limits on the mass of the neutral Z' boson, M_Z', predicted in…
Indirect precision data are used to constrain the masses of possible extra Z^prime bosons and their mixings with the ordinary Z. We study a variety of Z^prime bosons as they appear in E_6 and left-right unification models, the sequential Z…
At LEP~1, cross sections and cross section asymmetries may be analysed model independently. Cross sections depend on four, asymmetries on two free parameters. As an example, I discuss the model independent $Z$ boson mass determination from…
We review the status of heavy neutral gauge bosons, Z', with emphasis on constraints that arise in supersymmetric models, especially those motivated from superstring compactifications. We first summarize the current phenomenological…
A model of a light $Z'$ boson is constructed and phenomenological bounds are derived. This $Z'$ boson arises from a very simple extension to the Standard Model, and it is constrained to be light because the vacuum expectation values which…
The Abelian $Z'$ boson decay width is calculated in a model-independent approach. The analysis takes into consideration the special relations between the $Z'$ couplings to the Standard model fields proper to the renormalizable theories. The…
We study constraints on additional $Z'$ bosons predicted in the supersymmetric (SUSY) $E_6$ models by using the updated results of electroweak experiments -- $Z$-pole experiments, $m_W$ measurements and low-energy neutral current (LENC)…