DOI 10.1007/s100529900079
The 
process in
the standard and SUSY models
at high energies
G.J. Gounaris1 - P.I. Porfyriadis1 - F.M. Renard2
1 Department of Theoretical Physics, University of Thessaloniki,
GR-54006, Thessaloniki, Greece
2 Physique
Mathématique et Théorique,
UMR 5825
Université Montpellier II,
F-34095 Montpellier Cedex 5, France
Received: 3 February 1999 / Pulished online: 30 June 1999
Abstract
We study the helicity amplitudes of the process
at high energy, which
in the standard and SUSY models first arise at the
one-loop order. In the standard model (SM), the diagrams involve
W, charged-quark, and lepton loops, while in SUSY, we also have
contributions from chargino-, charged-sfermion, and Higgs-loop
diagrams. The SUSY contributions are most important in the region
above the threshold for producing the supersymmetric
partners; there, they interfere most effectively with
the primarily imaginary SM amplitudes. Simple expressions for
the relevant one-loop functions are given which provide a
direct overview of the behaviour of the helicity amplitudes
in the whole parameter space at high energies.
The various characteristics of a large set of
observables are studied in detail.
Copyright Springer-Verlag
