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