Associated production of heavy Higgs boson with top quarks

Abstract

Associated production of a heavy Higgs boson ( m H > 100 GeV) with top quarks at Juratron energies is studied. It is natural to differentiate between the “light” (2 m t < m H < 2 m W) and “heavy” ( m H > 2 m W) Higgs search. It is assumed that the mass value of the top quarks is in the interval m t ≈ 30–80 GeV. m W is the W-boson mass. If m H < 2 m W a dangerous background is given by the QCD production of four top quarks. We have calculated the cross sections for both the Higgs production and the background reaction. The disappointing result found is that the background is overwhelmingly large. However the Higgs search in this mass region is not hopeless. The associated production of the Higgs boson with a W-boson may have a clear experimental signature, its background given by the reaction p + p → W + t + t might be suppressed. The difficulty with this mechanism is that the rate is rather low. If m H > 2 m W the background is different and its contribution is expected to be small. The associated production of a Higgs boson with a pair of top quarks might be a useful method in the Higgs search in this case.