DOI 10.1007/s100529900174
Search for charginos and neutralinos
in e+e- collisions
at centre-of-mass energies near 183GeV
and
constraints on the MSSM parameter space
The ALEPH Collaboration
R. Barate - et al.
Laboratoire de Physique des Particules (LAPP), IN2P3-CNRS,
F-74019 Annecy-le-Vieux Cedex, France
Received: 8 February 1999 / Published online: 8 September 1999
Abstract
Searches for charginos and neutralinos are performed with the data
collected by the ALEPH detector at LEP at centre-of-mass energies near
183GeV. In these searches, it is assumed that R-parity is conserved and
that the lightest neutralino is the LSP. No evidence of a signal is observed
in the 57
accumulated, which excludes chargino and associated
neutralino production up to the kinematic limit over large regions of the
MSSM parameter space. Under the assumptions of common gaugino and common
sfermion masses at the unification scale, the interplay between the chargino,
neutralino and slepton exclusion limits allows a lower bound of 27
to be
set on the mass of the lightest neutralino. Tighter constraints on the MSSM
parameter space are obtained using in addition exclusions in the Higgs sector.
Finally, the results are interpreted within the framework of minimal
supergravity.
Copyright Springer-Verlag
