Top decay to lepton + jets: CDF B tags and cross section

摘要

The top search in the lepton plus jets channel with the Collider Detector at Fermilab (CDF) is presented. The analysis uses a 67 pb{sup {minus}1} data sample of p{bar p} collisions at {radical}s = 1.8 TeV. Soft lepton tagging (SLT) and secondary vertex tagging (SVX) of b jets are used to reduce backgrounds. A significant excess of events over expected backgrounds is seen, and together with the excess of observed events in the dilepton (DIL) channel, firmly establish the existence of the top quark. Combining all channels, the t{bar t} production cross section is measured to be {sigma} {sub t{bar t}} = 7.6{sub -2.0}{sup +2.4} pb. The Branching of top to Wb is measured to be Br(t {yields} Wb) = 0.87{sub -0.30}{sup +0.13}(stat) {sub -0.11}{sup +0.13}(syst).