Measurement of the inclusive t¯t production cross section in the lepton + jets channel in pp collisions at ffiffi ps = 7 TeV with the ATLAS detector using support vector machines

A measurement of the top quark pair-production cross section in the lepton þ jets decay channel is presented. It is based on 4.6 fb−1 of ffiffiffisp ¼ 7 TeV pp collision data collected during 2011 by the ATLAS experiment at the CERN Large Hadron Collider. A three-class, multidimensional event classifier based on support vector machines is used to differentiate t¯t events from backgrounds. The t¯t production cross section is found to be σt¯t ¼ 168.5 0.7ðstatÞ þ6.2 −5.9 ðsystÞ þ3.4 −3.2 ðlumiÞ pb. The result is consistent with the Standard Model prediction based on QCD calculations at next-to-next-to-leading ord ; BSF-NSF ; CEA-DRF ; Cantons of Bern and Geneva ; EU-ESF ; GenT Programmes Generalitat Valenciana, Spain ; GridKA ; INFN-CNAF ; La Caixa Banking Foundation ; MIZŠ ; MNE ; NDGF CC-IN2P3 ; Norwegian Financial Mechanism 2014-2021 ; PROMETEO ; RGC ; UNCE ; Wallenberg Foundation ; U.S. Department of Energy ; Alexander von Humboldt-Stiftung ; Alabama Space Grant Consortium ; Brookhaven National Laboratory ; CRC Health Group ; Canarie ; Karlsruhe Institute of Technology ; H2020 Marie Skłodowska-Curie Actions ; Multiple Sclerosis Scientific Research Foundation ; CERN ; Compute Canada ; Göran Gustafssons Stiftelser ; Natural Sciences and Engineering Research Council of Canada ; National Research Council Canada ; Canada Foundation for Innovation ; Science and Technology Facilities Council ; Leverhulme Trust ; European Research Council ; European Cooperation in Science and Technology ; Australian Research Council ; National Stroke Foundation ; Neurosurgical Research Foundation ; Helmholtz-Gemeinschaft ; Minerva Foundation ; Deutsche Forschungsgemeinschaft ; Agence Nationale de la Recherche ; Japan Society for the Promotion of Science ; Ministry of Education, Culture, Sports, Science and Technology ; Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung ; Danmarks Grundforskningsfond IN2P3-CNRS ; Fundação de Amparo à Pesquisa do Estado de São Paulo ; National Natural Science Foundation of China ...