Eur. Phys. J. C 10, 499-513
DOI 10.1007/s100529900131
The
process at high energies
and the search for virtual SUSY effects
G.J. Gounaris1 - J. Layssac2 - P.I. Porfyriadis1 - F.M. Renard2
1 Department of Theoretical Physics, Aristotle
University of Thessaloniki,
GR-54006, Thessaloniki, Greece
2 Physique
Mathématique et Théorique,
UMR 5825,
Université Montpellier II,
F-34095 Montpellier Cedex 5, France
Received: 26 April 1999 / Published online: 8 September 1999
Abstract
We study the helicity amplitudes and the observables
of the process at high energy.
As in the case of the
process
studied before, the relevant diagrams in the standard model (SM)
involve W, charged-quark, and lepton loops, while in SUSY we also have
contributions from charginos and charged-sfermion or Higgs-loop
diagrams. Above 250 GeV, the dominant SM amplitudes are
themselves dominated by the W loop, and
as for
, they are
helicity conserving and almost purely imaginary.
We discuss the complementary information provided
by
for the identification of possible nonstandard effects. This process, together
with
, should provide very
useful information on the nature of possible
new physics particles, above the threshold of their
direct production.
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