32 research outputs found
Model Independent Constraints at Future Colliders}
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
collider. Analytical exclusion limits are derived in the Born approximation.
The limits obtained with radiative corrections are always worse than those
calculated at the Born level. Polarized beams are only useful for degrees of
polarization essentially larger than 50\%. Known discovery limits on extra
bosons predicted by popular models are reproduced as special cases. The
constraints are compared to those predicted by four fermion contact
interactions.Comment: 10 Latex pages, uses epsf.sty, 5 uuencoded figures obtainable via
anonymous ftp from convex.ifh.de in /pub/preprint/ as file desy93-154.uu,
DESY 93-15
Experimental Constraints on the Scale of New Physics in Top Condensate Models
We obtain mass limits on the extra neutral gauge boson which is predicted in
a model with hidden gauge symmetry and dynamical breaking of the electroweak
symmetry by a top quark condensate. For typical model assumptions, present LEP
data exclude masses below 3\,TeV. With LEP200 or an electron-positron collider
of a c.m. energy of 500 GeV masses below 15\,TeV or 50\,TeV could be excluded,
respectively. Such high mass limits allow the calculation of the observables
used in the analysis in the context of the Nambu-Jona-Lasinio model.Comment: 7 pages, 2 figures(appended as PS files), DESY 93-111, LMU-04/9
Searching for a W' at the Next-Linear-Collider using Single Photons
We examine the sensitivity of the process e+e- -> nu nubar + gamma to
additional W-like bosons which arise in various models. The process is found to
be sensitive to W' masses up to several TeV.Comment: 8 pages, 8 figures, Latex. To appear in proceedings of "MRST '99:
High Energy Physics at the Millenium", May 10-12, 1999, Carleton U., Ottawa
(AIP
Model-Independent Limits from Electron-Electron Collisions
Model independent constraints on the mass of an extra neutral gauge boson and
its couplings to charged leptons are given for the option of a future
linear collider. Analytic exclusion limits are derived in the Born
approximation. The results are compared with those of the mode. The
influence of radiative corrections is discussed.Comment: 7 pages, LaTeX, 4 Figures, uuencoded Postscriptfile, MPI-Ph/94-23,
LMU-04/9
THE PROCESS AT LEP AND NLC
The cross sections for the reaction
and for similar four fermion production processes at LEP~1, LEP~2 and the NLC
are calculated. Due to the extraordinary symmetry properties of the process,
very compact analytical formulae describe the double differential distributions
in the invariant masses of the and pairs. The total
cross sections may be obtained with two numerical integrations.Comment: 10 pages (LaTeX), 1 table, 4 figures (not included, a uuencoded file
containing the LaTeX and all postscript files is available via anonymous ftp
from convex.ifh.de as /pub/preprint/desy94-185.uu), DESY 94-18