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The Constraint on FCNC Coupling of the Top Quark with a Gluon from ep Collisions

A. A. Ashimova·S. R. Slabospitsky
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Abstract

Using the constraint on the single top production cross-section obtained at the HERA collider, $σ(ep \to e t X)$, we evaluate an upper limit on oupling constant of the anomalous top quark interaction with a gluon via flavor-changing neutral current: $|κ_{tgq}/Λ| \le 0.4 {TeV}^{-1}$, BR$(t \to gq) < 13 % $

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A. A. Ashimova, S. R. Slabospitsky. 2008-08-25. The Constraint on FCNC Coupling of the Top Quark with a Gluon from ep Collisions. https://doi.org/10.1016/j.physletb.2008.08.065

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