EffectiveK-factors for gg H WW at the LHC

A simulation of the search for the Standard Model Higgs boson at the LHC, inthe channel gg -> H -> WW -> lnu lnu, is described. Higher-order QCDcorrections are taken into account by using a reweighting procedure, whichallows us to combine event rates obtained with the PYTHIA Monte Carlo programwith the most up-to-date theoretical predictions for the transverse-momentumspectra of the Higgs signal and its corresponding WW background. With thismethod the discovery potential for Higgs masses between 140 and 180 GeV isrecalculated and the potential statistical significance of this channel isfound to increase considerably. For a Higgs mass of 165 GeV asignal-to-background ratio of almost 2:1 can be obtained. A statisticalsignificance of five standard deviations might already be achieved with anintegrated luminosity close to 0.4 fb^{-1}. Using this approach, anexperimental effective K-factor of about 2.04 is obtained for the consideredHiggs signature, which is only about 15 % smaller than the theoreticalinclusive K-factor.Comment: 16 pages, 8 eps figures, comparison of jet veto efficiencies between PYTHIA and HERWIG added, to appear on JHE