DOI: 10.1140/epjc/s2002-01111-5
Search for an LSP gluino at LEP with the DELPHI detector
The DELPHI Collaboration(Received: 6 November 2002 / Published online: 15 January 2003 )
Abstract
In some supersymmetric models, the gluino (
) is predicted to be light
and stable. In that case, it would hadronize to form R-hadrons.
In these models, the missing energy signature of the lightest
supersymmetric particle is no longer valid, even if R-parity is conserved.
Therefore, such a gluino is not constrained by hadron collider results,
which looked for the decay
.
Data collected by the DELPHI detector in 1994 at 91.2 GeV have been analysed to
search for
events. No deviation from Standard Model
predictions is observed and a gluino mass between 2 and 18
GeV/c2 is
excluded at the 95% confidence level in these models. Then, R-hadrons produced
in the squark decays were searched for in the data collected by DELPHI
at the centre-of-mass energies of 189 to 208 GeV, corresponding to an
overall integrated luminosity of 609
pb-1.
The observed number of events is in agreement with the Standard
Model predictions. Limits at 95% confidence level are derived on the squark
masses from the excluded regions in the plane (
,
):




© Società Italiana di Fisica, Springer-Verlag 2003