Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV
BMWFW (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MES (Bulgaria) ; CERN ; CAS (China) ; MOST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; CSF (Croatia) ; RPF (Cyprus) ; SENESCYT (Ecuador) ; MoER (Estonia) ; ERC IUT (Estonia) ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; CNRS/IN2P3 (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; OTKA (Hungary) ; NIH (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; MSIP (Republic of Korea) ; NRF (Republic of Korea) ; LAS (Lithuania) ; MOE (Malaysia) ; UM (Malaysia) ; BUAP (Mexico) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; LNS (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MBIE (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Dubna) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; MESTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; Swiss Funding Agencies (Switzerland) ; MST (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; STAR (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; SFFR (Ukraine) ; STFC (United Kingdom) ; DOE (USA) ; NSF (USA) ; Marie-Curie programme ; European Research Council (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of the Czech Republic ; Council of Science and Industrial Research, India ; HOMING PLUS programme of the Foundation for Polish Science ; European Union, Regional Development Fund ; Mobility Plus programme of the Ministry of Science and Higher Education ; National Science Center (Poland) ; Thalis programme - EU-ESF ; Aristeia programme - EU-ESF ; Greek NSRF ; National Priorities Research Program by Qatar National Research Fund ; Programa Clarin-COFUND del Principado de Asturias ; Rachadapisek Sompot Fund for Postdoctoral Fellowship (Thailand) ; Chulalongkorn University (Thailand) ; Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand) ; Welch Foundation ; EPLANET (European Union) ; National Science Center (Poland): Harmonia 2014/14/M/ST2/00428 ; National Science Center (Poland): Opus 2013/11/B/ST2/04202 ; National Science Center (Poland): 2014/13/B/ST2/02543 ; National Science Center (Poland): 2014/15/B/ST2/ 03998 ; National Science Center (Poland): Sonata-bis 2012/07/E/ST2/01406 ; Welch Foundation: C-1845 ; The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark (Delta m(t) = m(t) - m((t) over bar)) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and at least four jets in the final state. The analysis is based on data corresponding to an integrated luminosity of 19.6 fb(-1) collected by the CMS experiment at the LHC, and yields a value of Delta m(t) = 0.15 0.19 (stat) +/- 0.09(syst) GeV, which is consistent with the SM expectation. This result is significantly more precise than previously reported measurements. (C) 2017 The Author(s). Published by Elsevier B.V.