Event shapes and azimuthal correlations in Z + jets events in pp collisions at s√=7 TeV

Measurements of event shapes and azimuthal correlations are presented for events where a Z boson is produced in association with jets in proton–proton collisions. The data collected with the CMS detector at the CERN LHC at View the MathML sources=7 TeV correspond to an integrated luminosity of 5.0 fb−15.0 fb−1. The analysis provides a test of predictions from perturbative QCD for a process that represents a substantial background to many physics channels. Results are presented as a function of jet multiplicity, for inclusive Z boson production and for Z bosons with transverse momenta greater than 150 GeV, and compared to predictions from Monte Carlo event generators that include leading-order multiparton matrix-element (with up to four hard partons in the final state) and next-to-leading-order simulations of Z+1-jetZ+1-jet events. The experimental results are corrected for detector effects, and can be compared directly with other QCD models.