NNLO QCD corrections for Z+jet and related processes

by Dr Alexander Huss (ETH Zürich)

Wednesday 1 Mar 2017, 13:00 → 14:00 Europe/Brussels

E/3rd floor-E.349 - Seminar room (E.349) (Marc de Hemptinne (chemin du Cyclotron, 2, Louvain-la-Neuve))

The Drell–Yan-like production of charged lepton pairs is among the most important so-called “standard candle” processes at the LHC. It provides the opportunity to test the Standard Model prediction over a large kinematic range and delivers crucial constraints in the fit of parton distribution functions. The production of a Z boson in association with a hadronic jet still retains a large event rate and also has the advantage of introducing a direct sensitivity to the strong coupling and the gluon PDF. As such, Z+jet production provides an ideal testing ground for our understanding of both strong and electroweak interactions in a hadron-collider environment. I present our calculation of the next-to-next-to-leading order (NNLO) QCD corrections to Z+jet production, which comprise various differential distributions for 8 TeV proton–proton collisions. I further discuss how this calculation can be used to describe the inclusive Z-boson production at non-vanishing transverse momentum and related observables. To this end, the theory prediction is compared to the measurements performed by the ATLAS and CMS collaborations. Here, the inclusion of NNLO QCD effects are found to result in a substantial improvement in the agreement between theory and data for the normalised distributions.

Slides ahuss_louvain_2017.pdf