Search for the standard model Higgs boson
in 
collisions
at
161-172 GeV
The OPAL Collaboration, K. Ackerstaff 8 et al.
8 CERN, European Organisation for Particle Physics, CH-1211 Geneva 23, Switzerland
Received: 19 August 1997
Abstract
This paper describes a search for the Standard Model Higgs boson
using data from 
collisions
collected at center-of-mass
energies of 161, 170 and 172 GeV by the OPAL detector at LEP.
The data collected at these energies correspond to integrated
luminosities of 10.0, 1.0 and 9.4 pb-1, respectively. The search is sensitive to
the main final states from the
process in which the Higgs boson is produced in association with a
fermion anti-fermion pair, namely
four jets, two jets with missing energy, and
two jets produced together with a pair of electron,
muon or tau leptons.
One candidate event is observed,
in agreement with the Standard Model background expectation.
In combination with previous OPAL
searches at center-of-mass energies close to the Z0 resonance
and the revised previous OPAL searches at
161 GeV , we derive a lower limit of 69.4 GeV
for the mass of the Standard Model Higgs boson
at the 95% confidence level.
Copyright Springer-Verlag
