https://doi.org/10.1140/epjc/s10052-022-10588-3
Regular Article - Experimental Physics
Direct constraint on the Higgs–charm coupling from a search for Higgs boson decays into charm quarks with the ATLAS detector
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Department of Physics, University of Adelaide, Adelaide, Australia
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Department of Physics, University of Alberta, Edmonton, AB, Canada
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Department of Physics, Ankara University, Ankara, Turkey
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Division of Physics, TOBB University of Economics and Technology, Ankara, Turkey
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LAPP, Univ. Savoie Mont Blanc, CNRS/IN2P3, Annecy, France
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Université de Paris, CNRS/IN2P3, AstroParticule et Cosmologie, Paris, France
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High Energy Physics Division, Argonne National Laboratory, Argonne, IL, USA
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Department of Physics, University of Arizona, Tucson, AZ, USA
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Department of Physics, University of Texas at Arlington, Arlington, TX, USA
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Physics Department, National and Kapodistrian University of Athens, Athens, Greece
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Physics Department, National Technical University of Athens, Zografou, Greece
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Department of Physics, University of Texas at Austin, Austin, TX, USA
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Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan
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Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology, Barcelona, Spain
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Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
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Physics Department, Tsinghua University, Beijing, China
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Department of Physics, Nanjing University, Nanjing, China
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University of Chinese Academy of Science (UCAS), Beijing, China
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Institute of Physics, University of Belgrade, Belgrade, Serbia
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Department for Physics and Technology, University of Bergen, Bergen, Norway
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Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, USA
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Institut für Physik, Humboldt Universität zu Berlin, Berlin, Germany
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Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland
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School of Physics and Astronomy, University of Birmingham, Birmingham, UK
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Department of Physics, Bogazici University, Istanbul, Turkey
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Department of Physics Engineering, Gaziantep University, Gaziantep, Turkey
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Department of Physics, Istanbul University, Istanbul, Turkey
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Istinye University, Sariyer, Istanbul, Turkey
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Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogotá, Colombia
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Departamento de Física, Universidad Nacional de Colombia, Bogotá, Colombia
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Dipartimento di Fisica e Astronomia A. Righi, Universitá di Bologna, Bologna, Italy
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INFN Sezione di Bologna, Bologna, Italy
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Physikalisches Institut, Universität Bonn, Bonn, Germany
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Department of Physics, Boston University, Boston, MA, USA
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Department of Physics, Brandeis University, Waltham, MA, USA
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Transilvania University of Brasov, Brasov, Romania
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Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania
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Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
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National Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department, Cluj-Napoca, Romania
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University Politehnica Bucharest, Bucharest, Romania
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West University in Timisoara, Timisoara, Romania
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Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovak Republic
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Department of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice, Slovak Republic
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Physics Department, Brookhaven National Laboratory, Upton, NY, USA
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Departamento de Física (FCEN) and IFIBA, Universidad de Buenos Aires and CONICET, Buenos Aires, Argentina
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California State University, Long Beach, CA, USA
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Cavendish Laboratory, University of Cambridge, Cambridge, UK
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Department of Physics, University of Cape Town, Cape Town, South Africa
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iThemba Labs, Johannesburg, Western Cape, South Africa
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Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg, South Africa
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National Institute of Physics, University of the Philippines Diliman (Philippines), Quezon City, Philippines
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Department of Physics, University of South Africa, Pretoria, South Africa
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University of Zululand, KwaDlangezwa, South Africa
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School of Physics, University of the Witwatersrand, Johannesburg, South Africa
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Department of Physics, Carleton University, Ottawa, ON, Canada
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Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies-Université Hassan II, Casablanca, Morocco
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Faculté des Sciences, Université Ibn-Tofail, Kenitra, Morocco
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Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA-Marrakech, Marrakech, Morocco
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LPMR, Faculté des Sciences, Université Mohamed Premier, Oujda, Morocco
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Faculté des sciences, Université Mohammed V, Rabat, Morocco
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Mohammed VI Polytechnic University, Ben Guerir, Morocco
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CERN, Geneva, Switzerland
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Enrico Fermi Institute, University of Chicago, Chicago, IL, USA
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LPC, Université Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand, France
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Nevis Laboratory, Columbia University, Irvington, NY, USA
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Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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Dipartimento di Fisica, Università della Calabria, Rende, Italy
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INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Frascati, Italy
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Physics Department, Southern Methodist University, Dallas, TX, USA
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Physics Department, University of Texas at Dallas, Richardson, TX, USA
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National Centre for Scientific Research “Demokritos”, Agia Paraskevi, Greece
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Department of Physics, Stockholm University, Sweden
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Oskar Klein Centre, Stockholm, Sweden
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Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen, Germany
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Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany
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Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany
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Department of Physics, Duke University, Durham, NC, USA
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SUPA-School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
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INFN e Laboratori Nazionali di Frascati, Frascati, Italy
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Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany
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Département de Physique Nucléaire et Corpusculaire, Université de Genève, Geneva, Switzerland
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Dipartimento di Fisica, Università di Genova, Genoa, Italy
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INFN Sezione di Genova, Genoa, Italy
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II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany
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SUPA-School of Physics and Astronomy, University of Glasgow, Glasgow, UK
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LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France
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Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, MA, USA
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Department of Modern Physics and State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, China
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Institute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao, China
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School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE), SKLPPC, Shanghai, China
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Tsung-Dao Lee Institute, Shanghai, China
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Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
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Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
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Department of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
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Department of Physics, University of Hong Kong, Hong Kong, China
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Department of Physics and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
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IJCLab, Université Paris-Saclay, CNRS/IN2P3, 91405, Orsay, France
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Department of Physics, Indiana University, Bloomington, IN, USA
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INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy
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ICTP, Trieste, Italy
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Dipartimento Politecnico di Ingegneria e Architettura, Università di Udine, Udine, Italy
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INFN Sezione di Lecce, Lecce, Italy
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Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy
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INFN Sezione di Milano, Milan, Italy
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Dipartimento di Fisica, Università di Milano, Milan, Italy
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INFN Sezione di Napoli, Naples, Italy
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Dipartimento di Fisica, Università di Napoli, Naples, Italy
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INFN Sezione di Pavia, Pavia, Italy
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Dipartimento di Fisica, Università di Pavia, Pavia, Italy
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INFN Sezione di Pisa, Pisa, Italy
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Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy
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INFN Sezione di Roma, Rome, Italy
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Dipartimento di Fisica, Sapienza Università di Roma, Rome, Italy
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INFN Sezione di Roma Tor Vergata, Rome, Italy
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Dipartimento di Fisica, Università di Roma Tor Vergata, Rome, Italy
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INFN Sezione di Roma Tre, Rome, Italy
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Dipartimento di Matematica e Fisica, Università Roma Tre, Rome, Italy
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INFN-TIFPA, Rome, Italy
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Università degli Studi di Trento, Trento, Italy
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Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria
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University of Iowa, Iowa City, IA, USA
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Department of Physics and Astronomy, Iowa State University, Ames, IA, USA
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Joint Institute for Nuclear Research, Dubna, Russia
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Departamento de Engenharia Elétrica, Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, Brazil
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Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil
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Instituto de Física, Universidade de São Paulo, São Paulo, Brazil
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Rio de Janeiro State University, Rio de Janeiro, Brazil
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KEK, High Energy Accelerator Research Organization, Tsukuba, Japan
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Graduate School of Science, Kobe University, Kobe, Japan
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AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Kraków, Poland
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Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
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Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland
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Faculty of Science, Kyoto University, Kyoto, Japan
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Kyoto University of Education, Kyoto, Japan
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Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka, Japan
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Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina
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Physics Department, Lancaster University, Lancaster, UK
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Oliver Lodge Laboratory, University of Liverpool, Liverpool, UK
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Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana, Slovenia
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School of Physics and Astronomy, Queen Mary University of London, London, UK
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Department of Physics, Royal Holloway University of London, Egham, UK
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Department of Physics and Astronomy, University College London, London, UK
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Louisiana Tech University, Ruston, LA, USA
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Fysiska institutionen, Lunds universitet, Lund, Sweden
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Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spain
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Institut für Physik, Universität Mainz, Mainz, Germany
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School of Physics and Astronomy, University of Manchester, Manchester, UK
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CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France
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Department of Physics, University of Massachusetts, Amherst, MA, USA
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Department of Physics, McGill University, Montreal, QC, Canada
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School of Physics, University of Melbourne, Victoria, Australia
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Department of Physics, University of Michigan, Ann Arbor, MI, USA
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Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA
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B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus
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Research Institute for Nuclear Problems of Byelorussian State University, Minsk, Belarus
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Group of Particle Physics, University of Montreal, Montreal, QC, Canada
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P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia
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National Research Nuclear University MEPhI, Moscow, Russia
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D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
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Fakultät für Physik, Ludwig-Maximilians-Universität München, Munich, Germany
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Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Munich, Germany
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Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan
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Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA
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Institute for Mathematics, Astrophysics and Particle Physics, Radboud University/Nikhef, Nijmegen, The Netherlands
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Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, The Netherlands
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Department of Physics, Northern Illinois University, DeKalb, IL, USA
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Budker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk, Russia
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Novosibirsk State University, Novosibirsk, Russia
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Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino, Russia
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Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre “Kurchatov Institute”, Moscow, Russia
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New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
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United Arab Emirates University, Al Ain, United Arab Emirates
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University of Sharjah, Sharjah, United Arab Emirates
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Department of Physics, New York University, New York, NY, USA
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Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan
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Ohio State University, Columbus, OH, USA
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Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK, USA
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Department of Physics, Oklahoma State University, Stillwater, OK, USA
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Palacký University, Joint Laboratory of Optics, Olomouc, Czech Republic
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Institute for Fundamental Science, University of Oregon, Eugene, OR, USA
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Graduate School of Science, Osaka University, Osaka, Japan
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Department of Physics, University of Oslo, Oslo, Norway
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Department of Physics, Oxford University, Oxford, UK
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LPNHE, Sorbonne Université, Université de Paris, CNRS/IN2P3, Paris, France
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Department of Physics, University of Pennsylvania, Philadelphia, PA, USA
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Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, PNPI, St. Petersburg, Russia
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Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, USA
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Laboratório de Instrumentação e Física Experimental de Partículas - LIP, Lisbon, Portugal
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Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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Departamento de Física, Universidade de Coimbra, Coimbra, Portugal
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Centro de Física Nuclear da Universidade de Lisboa, Lisbon, Portugal
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Departamento de Física, Universidade do Minho, Braga, Portugal
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Departamento de Física Teórica y del Cosmos, Universidad de Granada, Granada, Spain
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Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
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Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
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Czech Technical University in Prague, Prague, Czech Republic
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Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
200
Particle Physics Department, Rutherford Appleton Laboratory, Didcot, UK
201
IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
202
Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA, USA
203
Departamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
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Millennium Institute for Subatomic Physics at High Energy Frontier (SAPHIR), Santiago, Chile
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Instituto de Investigación Multidisciplinario en Ciencia y Tecnología y Departamento de Física, Universidad de La Serena, La Serena, Chile
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Universidad Andres Bello, Department of Physics, Santiago, Chile
207
Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
208
Departamento de Física, Universidad Técnica Federico Santa María, Valparaiso, Chile
209
Department of Physics, University of Washington, Seattle, WA, USA
210
Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
211
Department of Physics, Shinshu University, Nagano, Japan
212
Department Physik, Universität Siegen, Siegen, Germany
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Department of Physics, Simon Fraser University, Burnaby, BC, Canada
214
SLAC National Accelerator Laboratory, Stanford, CA, USA
215
Department of Physics, Royal Institute of Technology, Stockholm, Sweden
216
Departments of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA
217
Department of Physics and Astronomy, University of Sussex, Brighton, UK
218
School of Physics, University of Sydney, Sydney, Australia
219
Institute of Physics, Academia Sinica, Taipei, Taiwan
220
E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia
221
High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia
222
Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel
223
Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
224
Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
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International Center for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo, Japan
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Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
227
Tomsk State University, Tomsk, Russia
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Department of Physics, University of Toronto, Toronto, ON, Canada
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TRIUMF, Vancouver, BC, Canada
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Department of Physics and Astronomy, York University, Toronto, ON, Canada
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Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
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Department of Physics and Astronomy, Tufts University, Medford, MA, USA
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Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
234
Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden
235
Department of Physics, University of Illinois, Urbana, IL, USA
236
Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia-CSIC, Valencia, Spain
237
Department of Physics, University of British Columbia, Vancouver, BC, Canada
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Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
239
Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
240
Department of Physics, University of Warwick, Coventry, UK
241
Waseda University, Tokyo, Japan
242
Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
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Department of Physics, University of Wisconsin, Madison, WI, USA
244
Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany
245
Department of Physics, Yale University, New Haven, CT, USA
246
Borough of Manhattan Community College, City University of New York, New York, NY, USA
247
Center for High Energy Physics, Peking University, China
248
Centro Studi e Ricerche Enrico Fermi, Fermi, Italy
249
CERN, Geneva, Switzerland
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Département de Physique Nucléaire et Corpusculaire, Université de Genève, Geneva, Switzerland
251
Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona, Spain
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Department of Financial and Management Engineering, University of the Aegean, Chios, Greece
253
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA
254
Department of Physics and Astronomy, University of Louisville, Louisville, KY, USA
255
Department of Physics, Ben Gurion University of the Negev, Beer Sheva, Israel
256
Department of Physics, California State University, East Bay, Long Beach, USA
257
Department of Physics, California State University, Sacramento, USA
258
Department of Physics, King’s College London, London, UK
259
Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia
260
Department of Physics, University of Fribourg, Fribourg, Switzerland
261
Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
262
Graduate School of Science, Osaka University, Osaka, Japan
263
Hellenic Open University, Patras, Greece
264
Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain
265
Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany
266
Institute of Particle Physics (IPP), Victoria, Canada
267
Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia
268
Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid, Spain
269
Joint Institute for Nuclear Research, Dubna, Russia
270
Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia
271
National Research Nuclear University MEPhI, Moscow, Russia
272
Physics Department, An-Najah National University, Nablus, Palestine
273
Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
274
The City College of New York, New York, NY, USA
275
TRIUMF, Vancouver, BC, Canada
276
Universita di Napoli Parthenope, Napoli, Italy
277
University of Chinese Academy of Sciences (UCAS), Beijing, China
278
Yeditepe University, Physics Department, Istanbul, Turkey
279
CERN, 1211, Geneva 23, Switzerland
Received:
28
January
2022
Accepted:
6
July
2022
Published online:
18
August
2022
A search for the Higgs boson decaying into a pair of charm quarks is presented. The analysis uses proton–proton collisions to target the production of a Higgs boson in association with a leptonically decaying W or Z boson. The dataset delivered by the LHC at a centre-of-mass energy of √s=13 TeV and recorded by the ATLAS detector corresponds to an integrated luminosity of 139 
. Flavour-tagging algorithms are used to identify jets originating from the hadronisation of charm quarks. The analysis method is validated with the simultaneous measurement of WW, WZ and ZZ production, with observed (expected) significances of 2.6 (2.2) standard deviations above the background-only prediction for the 
process and 3.8 (4.6) standard deviations for the 
process. The 
search yields an observed (expected) upper limit of 26 (31) times the predicted Standard Model cross-section times branching fraction for a Higgs boson with a mass of 125 GeV, corresponding to an observed (expected) constraint on the charm Yukawa coupling modifier 
, at the 95% confidence level. A combination with the ATLAS 
analysis is performed, allowing the ratio 
to be constrained to less than 4.5 at the 95% confidence level, smaller than the ratio of the b- and c-quark masses, and therefore determines the Higgs-charm coupling to be weaker than the Higgs-bottom coupling at the 95% confidence level.
F. Bauer, V. Vrba, S. Zimmermann: Deceased.
© The Author(s) 2022
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