2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/36977A search for the Standard Model Higgs boson with the OPAL detector at LEP was reported. The analysis was based on the full data sample collected at center-of-mass energies of 192-209 GeV in 1999 and 2000, corresponding to an integrated luminosity of approximately 426 /pb. The data shows an excess in a range of 95-120 GeV. The data slightly favour the hypothesis that a signal is present, but also that the data are consistent with the background hypothesis. A lower bound of 109.7 GeV is obtained on the Higgs boson mass at the 95% confidence level.4 pages, 5 figures, to be published in the proceedings of XXXVI th Rencontres de Moriond Electroweak Interactions and Unified TheoriesHigh Energy Physics - Experimenttext