Measurements of the tt production cross section in lepton+jets final states in pp collisions at 8 TeV and ratio of 8 to 7 TeV cross sections

© 2017, CERN for the benefit of the CMS collaboration. A measurement of the top quark pair production (tt¯) cross section in proton–proton collisions at the centre-of-mass energy of 8TeV is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of...

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Bibliographic Details
Main Authors: The CMS Collaboration, Apyan, Aram, Barbieri, Richard Alexander, Baty, Austin Alan, Bierwagen, Katharina, Brandt, Stephanie Akemi, Busza, Wit, Cali, Ivan Amos, Demiragli, Zeynep, Di Matteo, Leonardo, Gomez-Ceballos, Guillelmo, Goncharov, Maxim, Gulhan, Doga Can, Iiyama, Yutaro, Innocenti, Gian Michele, Klute, Markus, Kovalskyi, Dmytro, Lai, Y.S., Lee, Y.-J., Levin, A., Luckey Jr, P David, Marini, Andrea Carlo, McGinn, Christopher Francis, Mironov, Camelia Maria, Narayanan, S., Niu, Xinmei, Paus, Christoph M. E., Ralph, D., Roland, Christof, Roland, Gunther, Salfeld-Nebgen, Jakob Maxillian Henry, Stephans, George S. F., Sumorok, Konstanty C, Varma, Mukund Madhav, Velicanu, Dragos Alexandru, Veverka, Jan, Wang, J., Wang, T.W., Wyslouch, Boleslaw, Yang, M., Zhukova, Victoria
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Published: Springer Nature 2022
Online Access:https://hdl.handle.net/1721.1/132150.2
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Summary:© 2017, CERN for the benefit of the CMS collaboration. A measurement of the top quark pair production (tt¯) cross section in proton–proton collisions at the centre-of-mass energy of 8TeV is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.6fb-1. This analysis is performed in the tt¯ decay channels with one isolated, high transverse momentum electron or muon and at least four jets, at least one of which is required to be identified as originating from hadronization of a b quark. The calibration of the jet energy scale and the efficiency of b jet identification are determined from data. The measured tt¯ cross section is 228.5±3.8(stat)±13.7(syst)±6.0(lumi) pb. This measurement is compared with an analysis of 7TeV data, corresponding to an integrated luminosity of 5.0fb-1, to determine the ratio of 8TeV to 7TeV cross sections, which is found to be 1.43±0.04(stat)±0.07(syst)±0.05(lumi). The measurements are in agreement with QCD predictions up to next-to-next-to-leading order.