Measurements of Top-Quark Pair Differential Cross-Sections in the eμ Channel in pp Collisions at √s̅ = 13 TeV Using the ATLAS Detector

Measurements of the production cross section of a Z boson in association with jets in proton–proton collisions at √s̅ = 13 TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb⁻¹ collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for events containing a Z boson decaying to electrons or muons and produced in association with up to seven jets with p_T > 30 GeV and |y| < 2.5. Predictions from different Monte Carlo generators based on leading-order and next-to-leading-order matrix elements for up to two additional partons interfaced with parton shower and fixed-order predictions at next-to-leading order and next-to-next-to-leading order are compared with the measured cross sections. Good agreement within the uncertainties is observed for most of the modelled quantities, in particular with the generators which use next-to-leading-order matrix elements and the more recent next-to-next-to-leading-order fixed-order predictions. © 2017, CERN for the benefit of the ATLAS collaboration.