UNIGE document Scientific Article
previous document  unige:39115  next document
add to browser collection

Observation of single top quark production and measurement of |Vtb| with CDF

CollaborationWith : Clark, Allan Geoffrey / Garcia Navarro, Jose Enrique / Lister, Alison / Wu, Xin
Published in Physical Review. D. 2010, vol. 82, no. 11, p. 112005
Abstract We report the observation of electroweak single top quark production in 3.2  fb−1 of pp collision data collected by the Collider Detector at Fermilab at s√=1.96  TeV. Candidate events in the W+jets topology with a leptonically decaying W boson are classified as signal-like by four parallel analyses based on likelihood functions, matrix elements, neural networks, and boosted decision trees. These results are combined using a super discriminant analysis based on genetically evolved neural networks in order to improve the sensitivity. This combined result is further combined with that of a search for a single top quark signal in an orthogonal sample of events with missing transverse energy plus jets and no charged lepton. We observe a signal consistent with the standard model prediction but inconsistent with the background-only model by 5.0 standard deviations, with a median expected sensitivity in excess of 5.9 standard deviations. We measure a production cross section of 2.3+0.6−0.5(stat+sys)  pb, extract the value of the Cabibbo-Kobayashi-Maskawa matrix element |Vtb|=0.91+0.11−0.11(stat+sys)±0.07  (theory), and set a lower limit |Vtb|>0.71 at the 95% C.L., assuming mt=175  GeV/c2.
Full text
(ISO format)
CDF COLLABORATION. Observation of single top quark production and measurement of |Vtb| with CDF. In: Physical Review. D, 2010, vol. 82, n° 11, p. 112005. https://archive-ouverte.unige.ch/unige:39115

164 hits



Deposited on : 2014-08-04

Export document
Format :
Citation style :