Evidence for production of single top quarks and first direct measurement of |Vtb|
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Updated: Jul 14, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
V M Abazov1, B Abbott, M Abolins
1Joint Institute for Nuclear Research, Dubna, Russia.
Abstract:
The D0 Collaboration presents first evidence for the production of single top quarks at the Fermilab Tevatron pp[over ] collider. Using a 0.9 fb(-1) dataset, we apply a multivariate analysis to separate signal from background and measure sigma(pp[over ]-->tb+X,tqb+X)=4.9+/-1.4 pb. The probability to measure a cross section at this value or higher in the absence of a signal is 0.035%, corresponding to a 3.4 standard deviation significance. We use the cross section measurement to directly determine the Cabibbo-Kobayashi-Maskawa matrix element that describes the Wtb coupling and find 0.68<|V(tb)|=1 at 95% C.L. within the standard model.
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