In Search Of The Standard Model Higgs Boson

A search for the Standard Model Higgs boson is conducted using data from the L3 detector at CERN's LEP collider during the year 2000. The integrated luminosity collected was 217.4 <italic>pb</italic><super>&minus;1</super> of electron-positron collisions at center-of-mass energies from 200 to 209 GeV. Presented here is a search for <italic>e</italic><super>+</super><italic> e</italic><super>&minus;</super> &rarr; <italic>hZ</italic>, where the Higgs decays into b quarks and the Z boson decays into undetected neutrinos. Also presented are combined results from the other L3 channels. The L3 combined results are consistent with the Standard Model background. Preliminary results from the LEP-wide combination are also shown. The lower limit on the Standard Model Higgs mass is found to be <display- math> <fd> <fl>m<inf>h</inf>&gt;114.1<hsp sp='0.167'><rm>GeV<hsp sp='0.167'> at<hsp sp='0.167'>95&percnt;<hsp sp='0.167'>C.L.</rm></fl> </fd> </display-math>In the LEP combination, an excess of data events is observed near <italic>m_h</italic> &sim; 115.6 GeV. Whether this is due to a statistical fluctuation or to Higgs production cannot be determined from the available set of data.