Rapidity distributions are presented for events containing either a Z boson or a photon with a single jet in proton-proton collisions produced at the CERN LHC. The data, collected with the CMS detector at root s = 7 TeV, correspond to an integrated luminosity of 5.0 fb(-1). The individual rapidity distributions of the boson and the jet are consistent within 5% with expectations from perturbative QCD. However, QCD predictions for the sum and the difference in rapidities of the two final-state objects show discrepancies with CMS data. In particular, next-to-leading-order QCD calculations, and two common Monte Carlo event generators using different methods to match matrix-element partons with parton showers, appear inconsistent with the data as well as with each other.
Rapidity distributions in exclusive Z plus jet and gamma plus jet events in pp collisions at root s=7 TeV
ABBRESCIA, Marcello;Colaleo, A.;DE PALMA, Mauro;MARANGELLI, Bartolomeo;MY, Salvatore;NUZZO, Salvatore Vitale;POMPILI, ALEXIS;SELVAGGI, Giovanna;Venditti, R.;
2013-01-01
Abstract
Rapidity distributions are presented for events containing either a Z boson or a photon with a single jet in proton-proton collisions produced at the CERN LHC. The data, collected with the CMS detector at root s = 7 TeV, correspond to an integrated luminosity of 5.0 fb(-1). The individual rapidity distributions of the boson and the jet are consistent within 5% with expectations from perturbative QCD. However, QCD predictions for the sum and the difference in rapidities of the two final-state objects show discrepancies with CMS data. In particular, next-to-leading-order QCD calculations, and two common Monte Carlo event generators using different methods to match matrix-element partons with parton showers, appear inconsistent with the data as well as with each other.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
