Top Mass and Decay Properties

In 1995 the top quark was discovered at the Tevatron proton-antiproton collider at Fermilab by the CDF and DØ collaborations [2, 3]. It is the most massive known elementary particle and the Tevatron collider is so far the only place to study the top quark. At the Tevatron collider, with a center-of-mass energy of √ s = 1.96 TeV, most top quarks are pair-produced via the strong interaction. In the standard model the top quark decays predominantly into a W boson and a b quark, with a branching ratio close to 100%. Different decay channels are distinguished according to the decay mode of the W -boson. Because of the difficult identification of τ -leptons all analyses presented in this article make no use of τ -leptons.