NLO QCD corrections to the production of ttZ in gluon fusion

We compute the O(αs) QCD corrections to the partonic process gg→ttZ at the LHC. This partonic channel is the dominant component of the scattering process pp→ttZ, which will be important for measuring the ttZ electroweak couplings. We perform this calculation using a newly developed numerical technique for obtaining loop corrections. The O(αs) corrections increase the total cross section by up to 75% for reasonable choices of the renormalization and factorization scales. Inclusion of these contributions decreases the residual scale dependence of the cross section coming from uncalculated higher order terms to ±5%