The narrowing search for the Higgs boson

In the Standard Model mass of a particle arises from spontaneous symmetry breaking. A byproduct of this mechanism is a particle called the Higgs boson. In a paper appearing in Phys. Rev. Lett. 102, 021802 (Published January 15, 2009), the CDF collaboration reports a search for the Higgs boson, via its expected decay to two W bosons. Based on a large amount of data (3 inverse femtobarns), they see no sign of the Higgs boson, and constrain its production cross section to less than ten times the prediction of the Standard Model. In fact, for the resonance energy of twice the W mass, or 160 GeV, they put an upper bound on the cross section for the decay to be less than twice the Standard Model prediction.