Lunch Seminars

Truth and beauty together: Evidence for s-channel single top production

by Yun-Tse Tsai (University of Rochester)

US/Central
F-108 (ANL, Bldg. 362)

F-108

ANL, Bldg. 362

Description
Single top quarks at the Tevatron are produced via the electroweak interaction from the decay of an off-shell W boson in the s-channel, or fusion of a virtual W boson with a b quark in the t-channel. In particular, the s-channel production rate is comparatively low at the LHC, and the much larger background contamination at the LHC would make it very difficult to measure the s-channel cross section. In this talk, I will present the analysis that led to the first evidence for s-channel single top-quark production. The measurement is based on 9.7/fb ppbar collisions at sqrt{s} = 1.96 TeV collected with the D0 detector. Both the s and t-channel cross sections are simultaneously measured without assuming the standard model prediction for either, and the CKM quark mixing matrix element |Vtb|, which describes the Wtb coupling, is directly determined.
Poster