We derive bounds on anomalous ZWW couplings, assuming that the residual apparent small discrepancy between the experimental and the MSM values of the ratio
R
b
=
Γ
b
/
Γ
h
of the Z widths into
b
b
...and into hadrons is entirely due to the “heavy” quark component of the
Zb
b
vertex. The
m
1
2 dependence of this quantity selects the Goldstone
H
± (or longitudinal
W
±) components of the anomalous couplings, and greatly reduces the number of involved parameters. For Λ of order 1 TeV we find the conservative 1 − σ bound −0.40⩽ (
f
w
M
Z
2/2
Λ
2−0.04
f
B
M
Z
2/2
Λ
2) ⩽ −0.15, that would lead to observable effects at LEP2.
We consider the production of chargino and charged Higgs boson pairs at future linear colliders for c.m. energies in the one TeV range. Working in the MSSM under the assumption of a "moderately" ...light SUSY scenario, we compute the leading (double) and next-to leading (linear) supersymmetric logarithmic terms of the so-called "Sudakov expansion" at one loop. We show that a combined analysis of the slopes of the chargino and of the charged Higgs production cross sections would offer a simple possibility for determining $\tan\beta$ for large ($\gtrsim 10$) values and an allowed strip in the ($M_2,\mu$) plane. This could provide a strong consistency test of the considered supersymmetric model.
We consider a large number of pair production processes at future colliders (LHC, ILC) for values of the c.m. energy in the TeV range, where a logarithmic expansion of Sudakov kind would provide a ...reliable description of Split supersymmetric electroweak effects. We calculate all the leading and next to leading terms of the expansions, that would differ drastically in the considered domain from those of an extreme "light" scenario. We imagine then two possible competitive future situations, at LHC and at ILC, where the determination of the energy dependence of the cross sections of certain processes could reveal a "signal" of the correct supersymmetric scheme.
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