DOI 10.1007/s100529800875
Search for anomalous production of di-lepton events
with missing
transverse momentum in e+e- collisions
at
and 172 GeV
The OPAL Collaboration
K.Ackerstaff8 - et al.
8 CERN, European Organisation for Particle Physics, CH-1211 Geneva 23, Switzerland
Received: 12 September 1997 / Published online: 24 April 1998
Abstract
Events containing two charged leptons and significant
missing transverse momentum are selected from
a data sample corresponding to a total integrated luminosity of 20.6 pb-1
at centre-of-mass energies of 161 GeV and 172 GeV.
The observed number of events, four at 161 GeV and nine at 172 GeV,
is consistent with the number expected from Standard Model processes,
predominantly arising from 
production with each W decaying
leptonically.
This topology is also an experimental
signature for the pair production of new particles that decay
to a charged lepton accompanied by one or more
invisible particles.
Further event selection criteria are described that optimise
the sensitivity to particular new physics channels.
No evidence for new phenomena is observed and limits
on the production
of scalar charged lepton pairs and other new particles are presented.
Copyright Springer-Verlag
