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′ constraints. Simple estimates of the
Z′ constraints from different reactions are derived. They make the physical origin of these constraints transparent. The results existing in the literature are summarized and compared with the estimates. The consequence of model assumptions on the
Z′ constraints is discussed. The paper starts with an overview of
Z′ parameters and the possible links between them by model assumptions. It continues with a discussion of
Z′ limits and
Z′ measurements in different reactions at
e
+
e
− and
μ
+
μ
− colliders. It follows an overview of the corresponding limits at proton colliders. Possible
Z′ constraints from other reactions as
ep collisions, atomic parity violation, neutrino scattering and cosmology are briefly mentioned.
Simple estimates for
Z′ exclusion limits and
Z′ model measurements in
pp(p
p)
collisions are derived. Due to the properties of the structure functions, the
Z′ exclusion limits depend only ...logarithmically on the
Z′ couplings to fermions and on the integrated luminosity. The predicted scaling of
Z′ exclusion limits and errors of
Z′ measurements with the c.m. energy and luminosity allows an easy extrapolation of existing analyses to other colliders.
Werner Heisenberg's work is the foundation for many topics of present research. This is also true for the search for extra gauge bosons. The prospects of future colliders in this search are shortly ...mentioned.
Model independent constraints on extra neutral gauge bosons are obtained from partial decay widths of the
Z
1 and forward-backward and left-right asymmetries at the
Z
1 peak. Constraints on the
ZZ′ ...mixing angle in
E
6 models are considered as special cases.
Physics with e+e− linear colliders Accomando, E.; Andreazza, A.; Ballestrero, A. ...
Physics reports,
06/1998, Letnik:
299, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The physics potential of
e
+
e
− linear colliders is summarized in this report. These machines are planned to operate in the first phase at a center-of-mass energy of 500
GeV, before being scaled up ...to about 1
TeV. In the second phase of the operation, a final energy of about 2
TeV is expected. The machines will allow us to perform precision tests of the heavy particles in the Standard Model, the top quark and the electroweak bosons. They are ideal facilities for exploring the properties of Higgs particles, in particular in the intermediate mass range. New vector bosons and novel matter particles in extended gauge theories can be searched for and studied thoroughly. The machines provide unique opportunities for the discovery of particles in supersymmetric extensions of the Standard Model, the spectrum of Higgs particles, the supersymmetric partners of the electroweak gauge and Higgs bosons, and of the matter particles. High precision analyses of their properties and interactions will allow for extrapolations to energy scales close to the Planck scale where gravity becomes significant. In alternative scenarios, i.e. compositeness models, novel matter particles and interactions can be discovered and investigated in the energy range above the existing colliders up to the TeV scale. Whatever scenario is realized in Nature, the discovery potential of
e
+
e
− linear colliders and the high precision with which the properties of particles and their interactions can be analyzed, define an exciting physics program complementary to hadron machines.
The present status of calculations of four fermion final states is reviewed. Problems arising in higher orders are pointed out. Special attention is paid to results obtained in the semi-analytical ...approach and their limitations and perspectives.
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