Z-Boson Production in Association with a Jet at Next-To-Next-To-Leading Order in Perturbative QCD

Abstract

We present the first complete calculation of Z-boson production in association with a jet in hadronic collisions through next-to-next-to-leading order in perturbative QCD. Our computation uses the recently-proposed N -jettiness subtraction scheme to regulate the infrared divergences that appear in the real-emission contributions. We present phenomenological results for 13 TeV protonproton collisions with fully realistic fiducial cuts on the final-state particles. The remaining theoretical uncertainties after the inclusion of our calculations are at the percent-level, making the Z+jet channel ready for precision studies at the LHC Run II.

Color-singlet production at NNLO in MCFM

“…The corresponding two-loop soft functions are also known for zero-jettiness [71,72] and for general Njettiness [73]. The first process calculated at NNLO using this method was pp → W +jet [16], followed by calculations of the pp → Higgs+jet [8] and pp → Z +jet [18] processes, and by detailed phenomenological studies of these processes at this order [74][75][76]. pp → H and pp → Z were also calculated using this method [4].…”

“…For NNLO calculations, this was expanded by using a hybrid g/MPI version of MCFM for use on computing clusters to facilitate the numerical NNLO calculations of Ref. [18]. Using the hybrid version of MCFM we can calculate NNLO distributions efficiently within a reasonable timescale.…”

NNLO QCD corrections for $Z$ boson plus jet production

“…This comparison uncovered an error in the numerical code used in [7], which alters their published results. After correction of this error, the code developed in [7] agrees with our results.…”

“…A second calculation of Z+jet production at NNLO precision has been presented by Boughezal et al [7] using a different subtraction scheme. In coordination with the authors of [7], we performed an in-depth comparison, by running our code with their settings (cuts, parton distributions, scale choice).…”

“…In coordination with the authors of [7], we performed an in-depth comparison, by running our code with their settings (cuts, parton distributions, scale choice). This comparison uncovered an error in the numerical code used in [7], which alters their published results. After correction of this error, the code developed in [7] agrees with our results.…”