Next-to-leading order QCD corrections to tt¯Z production at the LHC

We present a calculation of the full next-to-leading order QCD corrections to the scattering process pp→tt¯Z. This channel will be used to measure the tt¯Z electroweak couplings at the Large Hadron Collider. These couplings cannot be directly measured in current experiments. To obtain these results, we utilize a novel, completely numerical approach to performing higher order QCD calculations. We find that for reasonable values of the renormalization and factorization scales the QCD corrections increase the leading order result by 35%, while reducing the theoretical error arising from uncalculated higher order corrections to approximately ±10%.