Search for the standard model higgs boson in e+ e- collisions at s**(1/2) = 161-GeV

This paper describes a search for the Standard Model Higgs boson using data from e^+e^- 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 Z^0 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.

electron positron: colliding beams
electron positron: annihilation
Higgs particle: search for
Higgs particle: mass
lower limit
Z0: associated production
Higgs particle: decay modes
Z0: decay modes
OPAL
experimental results

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