We report on the calculation of the full next-to-leading-order QCD corrections to the production of $t\overline{t}b\overline{b}$ final states at the LHC, which deliver a serious background contribution to the production of a Higgs boson (decaying into a $b\overline{b}$ pair) in association with a $t\overline{t}$ pair. While the corrections significantly reduce the unphysical scale dependence of the leading-order cross section, our results predict an enhancement of the $t\overline{t}b\overline{b}$ production cross section by a $K$ factor of about 1.8.

• Received 1 May 2009

DOI:https://doi.org/10.1103/PhysRevLett.103.012002