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arXiv · hep-ex/0012029

First Measurement of the Ratio B(t-->Wb)/B(t-->Wq) and Associated Limit on the CKM Element Vtb

CDF Collaboration
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Abstract

We present the first measurement of the ratio of branching fraction R= B(t-->wb)/B(t-->Wq) from ppbar collisions at sqrt(s)=1.8 TeV. The data set corresponds to 109 pb-1 of data recorded by the Collider Detector at Fermilab during the 1992-1995 Tevatron run. We measure R=0.94+.31-.24 (stat+syst) or R>0.61 (0.56) at 90 (95) %C.L., in agreement with the standard model predictions. This measurement yields a limit of the Cabibbo-Kobayashi-Maskawa quark mixing matrix element Vtb under the assumption of three generation unitarity.

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CDF Collaboration. 2000-12-11. First Measurement of the Ratio B(t-->Wb)/B(t-->Wq) and Associated Limit on the CKM Element Vtb. https://doi.org/10.1103/physrevlett.86.3233

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