Search for excited leptons in ??? final states in proton-proton collisions at ?s=13 TeV

Abstract

A search is presented for excited electrons and muons in ??? final states at the LHC. The search is based on a data sample corresponding to an integrated luminosity of 35.9 fb ?1 of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector in 2016. This is the first search for excited leptons at s = 13 TeV. The observation is consistent with the standard model background prediction, and the most stringent exclusion limits to date are set on the excited lepton mass and the compositeness scale, at 95% confidence level. Excited electrons and muons are excluded for masses below 3.9 and 3.8 TeV, respectively, under the assumption that the excited lepton mass equals the compositeness scale. The best observed limit on the compositeness scale is obtained with an excited lepton mass of around 1.0 TeV, excluding values below 25 TeV for both excited electrons and muons.[Figure not available: see fulltext.]. © 2019, The Author(s). ; California Earthquake Authority, CEA Secretaría de Educación Superior, Ciencia, Tecnología e Innovación, SENESCYT Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, FAPERJ State Fund for Fundamental Research of Ukraine, SFFR CS Fund, CSF Fundação para a Ciência e a Tecnologia, FCT Joint Institute for Nuclear Research, JINR Ministry of Education - Singapore, MOE Pakistan Atomic Energy Commission, PAEC Consejo Nacional de Ciencia y Tecnología, CONACYT National Science and Technology Development Agency, ????: Thailand Ministry for Business Innovation and Employment, MBIE Ministry of Science and Technology, MOST Institute for Research in Fundamental Sciences, IPM Missouri University of Science and Technology, MST Hispanics in Philanthropy, HIP European Regional Development Fund, FEDER Benemérita Universidad Autónoma de Puebla, BUAP Deutsche Forschungsgemeinschaft, DFG National Research Foundation of Korea, NRF Secretaría de Estado de Investigación, Desarrollo e Innovación, SEIDI Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, FAPERGS Ministry of Science, ICT and Future Planning, MSIP Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie, BMBWF Ministry of Science,Technology and Research, MoSTR U.S. Department of Energy, USDOE Academy of Finland Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES Norwegian Sequencing Centre, NSC Türkiye Atom Enerjisi Kurumu, TAEK Mountain Equipment Co-operative, MEC Research Promotion Foundation, ???? National Science Foundation, NSF Science and Technology Facilities Council, STFC Helmholtz-Gemeinschaft, HGF Austrian Science Fund, FWF Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP Secretaría de Educación Pública, SEP Fonds De La Recherche Scientifique - FNRS, FNRS National Academy of Sciences of Ukraine, NASU National Natural Science Foundation of China, NSFC Bundesministerium für Bildung und Forschung, BMBF Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, CINVESTAV Instituto Nazionale di Fisica Nucleare, INFN Department of Atomic Energy, Government of India, ???? Universiti Malaya, UM Royal Astronomical Society, RAS Department of Science and Technology, Government of West Bengal, DST State Atomic Energy Corporation ROSATOM, ROSATOM Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq Russian Foundation for Basic Research, ???? Maryland Ornithological Society, MOS College of Arts and Sciences, University of Nebraska-Lincoln, CAS CERN European Regional Development Fund, FEDER General Secretariat for Research and Technology, GSRT Fonds Wetenschappelijk Onderzoek, FWO Science Foundation Ireland, SFI Ministry of Education and Science, MES Louisiana Academy of Sciences, LAS Institute for the Promotion of Teaching Science and Technology, IPST National Research Center "Kurchatov Institute", NRC KI Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA European Regional Development Fund, FEDER Horizon 2020: 675440 Fundacja na rzecz Nauki Polskiej, FNP Belgian Federal Science Policy Office, BELSPO Agentschap voor Innovatie door Wetenschap en Technologie, IWT Alexander von Humboldt-Stiftung Ministerstvo Školství, Mláde?e a T?lov?chovy, MŠMT European Commission, EC A.G. Leventis Foundation Ministerstvo Školství, Mláde?e a T?lov?chovy, MŠMT 30820817 Fonds Wetenschappelijk Onderzoek, FWO European Research Council, ERC Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture, FRIA Magyar Tudományos Akadémia, MTA Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA: 125105, 124850, 123842, 123959, 124845 Welch Foundation: C-1845 Comisión Asesora de Investigación Científica y Técnica, CAICYT: MDM-2015-0509 Qatar National Research Fund, QNRF Chulalongkorn University, CU Weston Havens Foundation ; Open Access, Copyright CERN, for the benefit of the CMS Collaboration. Article funded by SCOAP3. ; We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COL-CIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.). ; Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract No. 675440 (European Union); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the "Excellence of Science — EOS" — be.h project n. 30820817; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Lendület ("Momentum") Program and the János Bolyai Research Scholarship of the Hungarian Academy of Sciences, the New National Excellence Program ÚNKP, the NKFIA research grants 123842, 123959, 124845, 124850 and 125105 (Hungary); the Council of Science and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center (Poland), contracts ; Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Research Program by Qatar National Research Fund; the Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia María de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.).