This paper presents studies of the performance of several jet-substructure techniques, which are used to identify hadronically decaying top quarks with high transverse momentum contained in large-radius jets. The efficiency of identifying top quarks is measured using a sample of top-quark pairs and the rate of wrongly identifying jets from other quarks or gluons as top quarks is measured using multijet events collected with the ATLAS experiment in 20.3 fb−1 of 8 TeV proton-proton collisions at the Large Hadron Collider. Predictions from Monte Carlo simulations are found to provide an accurate description of the performance. The techniques are compared in terms of signal efficiency and background rejection using simulations, covering a larger range in jet transverse momenta than accessible in the dataset. Additionally, a novel technique is developed that is optimized to reconstruct top quarks in events with many jets.
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172.Dipartimento di FisicaSapienza Università di RomaRomaItaly
173.INFN Sezione di Roma Tor VergataRomaItaly
174.Dipartimento di FisicaUniversità di Roma Tor VergataRomaItaly
175.INFN Sezione di Roma TreRomaItaly
176.Dipartimento di Matematica e FisicaUniversità Roma TreRomaItaly
177.Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies - Université Hassan IICasablancaMorocco
178.Centre National de l’Energie des Sciences Techniques NucleairesRabatMorocco
179.Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA-MarrakechMarrakechMorocco
180.Faculté des Sciences, Université Mohamed Premier and LPTPMOujdaMorocco
181.Faculté des sciencesUniversité Mohammed VRabatMorocco
182.DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energies Alternatives)Gif-sur-YvetteFrance
183.Santa Cruz Institute for Particle PhysicsUniversity of California Santa CruzSanta CruzU.S.A.
184.Department of PhysicsUniversity of WashingtonSeattleU.S.A.
185.Department of Physics and AstronomyUniversity of SheffieldSheffieldU.K.
186.Department of PhysicsShinshu UniversityNaganoJapan
188.Department of PhysicsSimon Fraser UniversityBurnabyCanada
189.SLAC National Accelerator LaboratoryStanfordU.S.A.
190.Faculty of Mathematics, Physics & InformaticsComenius UniversityBratislavaSlovak Republic
191.Department of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of SciencesKosiceSlovak Republic
192.Department of PhysicsUniversity of Cape TownCape TownSouth Africa
193.Department of PhysicsUniversity of JohannesburgJohannesburgSouth Africa
194.School of PhysicsUniversity of the WitwatersrandJohannesburgSouth Africa
195.Department of PhysicsStockholm UniversityStockholmSweden
196.The Oskar Klein CentreStockholmSweden
197.Physics DepartmentRoyal Institute of TechnologyStockholmSweden
198.Departments of Physics & Astronomy and ChemistryStony Brook UniversityStony BrookU.S.A.
199.Department of Physics and AstronomyUniversity of SussexBrightonU.K.
200.School of PhysicsUniversity of SydneySydneyAustralia
201.Institute of PhysicsAcademia SinicaTaipeiTaiwan
202.Department of PhysicsTechnion: Israel Institute of TechnologyHaifaIsrael
203.Raymond and Beverly Sackler School of Physics and AstronomyTel Aviv UniversityTel AvivIsrael
204.Department of PhysicsAristotle University of ThessalonikiThessalonikiGreece
205.International Center for Elementary Particle Physics and Department of PhysicsThe University of TokyoTokyoJapan
206.Graduate School of Science and TechnologyTokyo Metropolitan UniversityTokyoJapan
207.Department of PhysicsTokyo Institute of TechnologyTokyoJapan
208.Department of PhysicsUniversity of TorontoTorontoCanada
209.TRIUMFVancouverCanada
210.Department of Physics and AstronomyYork UniversityTorontoCanada
211.Faculty of Pure and Applied Sciences, and Center for Integrated Research in Fundamental Science and EngineeringUniversity of TsukubaTsukubaJapan
212.Department of Physics and AstronomyTufts UniversityMedfordU.S.A.
213.Department of Physics and AstronomyUniversity of California IrvineIrvineU.S.A.
214.INFN Gruppo Collegato di UdineSezione di TriesteUdineItaly
215.ICTPTriesteItaly
216.Dipartimento di Chimica, Fisica e AmbienteUniversità di UdineUdineItaly
217.Department of Physics and AstronomyUniversity of UppsalaUppsalaSweden
218.Department of PhysicsUniversity of IllinoisUrbanaU.S.A.
219.Instituto de Física Corpuscular (IFIC) and Departamento de Física Atómica, Molecular y Nuclear and Departamento de Ingeniería Electrónica and Instituto de Microelectrónica de Barcelona (IMB-CNM), University of Valencia and CSICValenciaSpain
220.Department of PhysicsUniversity of British ColumbiaVancouverCanada
221.Department of Physics and AstronomyUniversity of VictoriaVictoriaCanada
222.Department of PhysicsUniversity of WarwickCoventryU.K.
223.Waseda UniversityTokyoJapan
224.Department of Particle PhysicsThe Weizmann Institute of ScienceRehovotIsrael
225.Department of PhysicsUniversity of WisconsinMadisonU.S.A.
226.Fakultät für Physik und AstronomieJulius-Maximilians-UniversitätWürzburgGermany
227.Fakultät für Mathematik und Naturwissenschaften, Fachgruppe PhysikBergische Universität WuppertalWuppertalGermany
228.Department of PhysicsYale UniversityNew HavenU.S.A.
229.Yerevan Physics InstituteYerevanArmenia
230.Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3)VilleurbanneFrance
231.Department of PhysicsKing’s College LondonLondonU.K.
232.Novosibirsk State UniversityNovosibirskRussia
233.Department of PhysicsCalifornia State UniversityFresnoU.S.A.
234.Department of PhysicsUniversity of FribourgFribourgSwitzerland
235.Departament de Fisica de la Universitat Autonoma de BarcelonaBarcelonaSpain
236.Departamento de Fisica e Astronomia, Faculdade de CienciasUniversidade do PortoPortoPortugal
237.Tomsk State UniversityTomskRussia
238.Universita di Napoli ParthenopeNapoliItaly
239.Institute of Particle Physics (IPP)TorontoCanada
240.Department of PhysicsSt. Petersburg State Polytechnical UniversitySt. PetersburgRussia
241.Institucio Catalana de Recerca i Estudis Avancats, ICREABarcelonaSpain
242.Department of PhysicsNational Tsing Hua UniversityHsinchuTaiwan
243.Department of PhysicsThe University of Texas at AustinAustinU.S.A.
244.Institute of Theoretical PhysicsIlia State UniversityTbilisiGeorgia
245.Georgian Technical University (GTU)TbilisiGeorgia
