2015/11/30 by Michal Czakon, David Heymes, Alexander Mitov · 1 citation
Physics and Astronomy · #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevlett.116.082003
published as Phys. Rev. Lett. 116, 082003 (2016) · Updated version matching the version published in PRL. Data files with all results attached
arxiv created 2016/03/16 · arxiv updated 2016/03/17
We present the first complete next-to-next-to-leading order (NNLO) QCD predictions for differential distributions in the top-quark pair production process at the LHC. Our results are derived from a fully differential partonic Monte Carlo calculation with stable top quarks which involves no approximations beyond the fixed-order truncation of the perturbation series. The NNLO corrections improve the agreement between existing LHC measurements [V. Khachatryan et al. (CMS Collaboration), Eur. Phys. J. C 75, 542 (2015)] and standard model predictions for the top-quark transverse momentum distribution, thus helping alleviate one long-standing discrepancy. The shape of the top-quark pair invariant mass distribution turns out to be stable with respect to radiative corrections beyond NLO which increases the value of this observable as a place to search for physics beyond the standard model. The results presented here provide essential input for parton distribution function fits, implementation of higher-order effects in Monte Carlo generators as well as top-quark mass and strong coupling determination.