Search for Z' resonances decaying to tt- in dilepton+jets final states in pp collisions at root s=7 TeV

Abstract

A search for resonances decaying to top quark-antiquark pairs is performed using a dilepton+jets data sample recorded by the CMS experiment at the LHC in pp collisions at ?s=7 TeV corresponding to an integrated luminosity of 5.0 fb-1. No significant deviations from the standard model background are observed. Upper limits are presented for the production cross section times branching fraction of top quark-antiquark resonances for masses from 750 to 3000 GeV. In particular, the existence of a leptophobic topcolor particle Z? is excluded at the 95% confidence level for resonance masses MZ ?<1.3 TeV for ?Z?=0.012MZ ?, and M<1.9 TeV for ?Z?=0.10MZ ?.