Search for the Standard Model Higgs boson

Abstract Using a data sample corresponding to about 1 233 000 hadronic Z decays collected by the ALEPH experiment at LEP, the reaction e + e − → HZ ∗ has been used to search for the standard model Higgs boson, in association with missing energy when Z ∗ → v v , or with a pair of energetic leptons when Z ∗ → e + e − or μ + μ − . No signal was found and, at the 95% confidence level, m H exceeds 58.4 GeV/ c 2 .