Measurement Of Top Quark Antiquark Pair Production In Association With A Z Boson With A Trilepton Final State In Pp Collisions At 8 Tev Center Of Mass Energy

Download or read book Measurement of Top Quark-antiquark Pair Production in Association with a Z Boson with a Trilepton Final State in Pp Collisions at 8 TeV Center of Mass Energy written by Ian Christopher MacNeill and published by . This book was released on 2015 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for Z boson production with associated top-antitop pairs is performed with a final state which contains trileptons and b-tagged jets. The measurement is performed on the complete dataset of pp collisions at a center-of-mass energy of 8 TeV collected at the CMS detector, for a total instantaneous luminosity of 19.5 fb−1. A cross section is calculated for this final state and compared to the standard model prediction. The cross section for tt̄Z production is measured to be sigma=194+105/−89 fb. The measured cross section to theoretical cross section ratio is 0.94+0̇̇̇·51/−43. The process is measured with a significance of 2.33. This measurement is then combined with an outside 4 lepton channel measurement for an equivalent cross section measurement of sigma=200+90/−76 fb and a significance of 3.1.