@article{10902/14004, year = {2014}, month = {11}, url = {http://hdl.handle.net/10902/14004}, abstract = {A search is presented for standard model (SM) production of four top quarks (tt¯tt¯) in pp collisions in the lepton + jets channel. The data correspond to an integrated luminosity of 19.6 fb-1 recorded at a centre-of-mass energy of 8 TeV with the CMS detector at the CERN LHC. The expected cross section for SM tt¯tt¯ production is sSMtt¯tt¯˜1fb. A combination of kinematic reconstruction and multivariate techniques is used to distinguish between the small signal and large background. The data are consistent with expectations of the SM, and an upper limit of 32 fb is set at a 95% confidence level on the cross section for producing four top quarks in the SM, where a limit of 32 ± 17 fb is expected.}, publisher = {Springer Verlag}, publisher = {Journal of High Energy Physics, Vol. 2014, Num. 11, Art. Num. 154}, title = {Search for standard model production of four top quarks in the lepton + jets channel in pp collisions at √s = 8 TeV}, author = {Khachatryan, Vladimir and Brochero Cifuentes, Javier Andrés and Cabrillo Bartolomé, José Iban and Calderón Tazón, Alicia and Duarte Campderros, Jorge and Fernández García, Marcos and Gómez Gramuglio, Gervasio and Graziano, Alberto and López Virto, María Amparo and Marco de Lucas, Jesús and Marco de Lucas, Rafael José and Martínez Rivero, Celso and Matorras Weinig, Francisco and Muñoz Sánchez, Francisca Javiela and Piedra Gómez, Jonatan and Rodrigo Anoro, Teresa and Rodríguez Marrero, Ana Yaiza and Ruiz Jimeno, Alberto and Scodellaro, Luca and Vila Álvarez, Iván and Vilar Cortabitarte, Rocío}, }