Closing in on the Higgs Boson
The Standard Model describes the unification of electromagnetic and weak interactions. It has been thoroughly tested over the past forty years, and represents one of the major successes of modern physics. This theory predicted the existence and the masses of the weak bosons. The last remaining piece of the puzzle is the Higgs boson whose existence is crucial for our understanding of the origin of particle masses.
Direct searches at LEP put a lower limit on the mass of the Higgs boson and, together with precision measurements, constrained it to <~200 GeV. Recently, the Tevatron and LHC experiments have excluded the existence of a Higgs boson with higher masses. In particular, results from the LHC experiments obtained with the full data set narrowed down the allowed mass range of the Higgs boson to the region between 115 and 130 GeV.
I will discuss searches for the SM Higgs boson with the D0 experiment at the Tevatron, highlighting the most important techniques. I will also draw a parallel with current and future searches at the LHC, showing what we can learn from our Tevatron experience. I will emphasize the future direction of the LHC experiments in light of a discovery consistent with the signature of the Higgs boson.