Search for the Standard Model Higgs Boson at LEP II

 The Higgs Boson is the last missing ingredient of the Standard Model of elektroweak interactions. The Higgs mechanism is responsible for the elektroweak symmetry breaking.
Although the Higgs Boson has not been found, indirect limits on its mass can be derived from high precision electroweak data. These fits are regularily performed by the LEP-electroweak-working-group. Direct searches at LEP I could exclude a Higgs Boson with a mass below 60 GeV.
At LEPII one can extend these searches. If the Higgs-Boson is not too heavy it can be produced in association with a Z-Boson (the corresponding Feynman-Diagram is shown at the left.)