Eur. Phys. J. C (2024) 84: 455
https://doi.org/10.1140/epjc/s10052-024-12657-1

Regular Article - Experimental Physics

Improving topological cluster reconstruction using calorimeter cell timing in ATLAS

¹ Department of Physics, University of Adelaide, Adelaide, Australia
² Department of Physics, University of Alberta, Edmonton, AB, Canada
³ Department of Physics, Ankara University, Ankara, Türkiye
⁴ Division of Physics, TOBB University of Economics and Technology, Ankara, Türkiye
⁵ LAPP, Université Savoie Mont Blanc, CNRS/IN2P3, Annecy, France
⁶ APC, Université Paris Cité, CNRS/IN2P3, Paris, France
⁷ High Energy Physics Division, Argonne National Laboratory, Argonne, IL, USA
⁸ Department of Physics, University of Arizona, Tucson, AZ, USA
⁹ Department of Physics, University of Texas at Arlington, Arlington, TX, USA
¹⁰ Physics Department, National and Kapodistrian University of Athens, Athens, Greece
¹¹ Physics Department, National Technical University of Athens, Zografou, Greece
¹² Department of Physics, University of Texas at Austin, Austin, TX, USA
¹³ Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan
¹⁴ Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology, Barcelona, Spain
¹⁵ Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
¹⁶ Physics Department, Tsinghua University, Beijing, China
¹⁷ Department of Physics, Nanjing University, Nanjing, China
¹⁸ School of Science, Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
¹⁹ University of Chinese Academy of Science (UCAS), Beijing, China
²⁰ Institute of Physics, University of Belgrade, Belgrade, Serbia
²¹ Department for Physics and Technology, University of Bergen, Bergen, Norway
²² Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
²³ University of California, Berkeley, CA, USA
²⁴ Institut für Physik, Humboldt Universität zu Berlin, Berlin, Germany
²⁵ Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland
²⁶ School of Physics and Astronomy, University of Birmingham, Birmingham, UK
²⁷ Department of Physics, Bogazici University, Istanbul, Türkiye
²⁸ Department of Physics Engineering, Gaziantep University, Gaziantep, Türkiye
²⁹ Department of Physics, Istanbul University, Istanbul, Türkiye
³⁰ Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogotá, Colombia
³¹ Departamento de Física, Universidad Nacional de Colombia, Bogotá, Colombia
³² Dipartimento di Fisica e Astronomia A. Righi, Università di Bologna, Bologna, Italy
³³ INFN Sezione di Bologna, Bologna, Italy
³⁴ Physikalisches Institut, Universität Bonn, Bonn, Germany
³⁵ Department of Physics, Boston University, Boston, MA, USA
³⁶ Department of Physics, Brandeis University, Waltham, MA, USA
³⁷ Transilvania University of Brasov, Brasov, Romania
³⁸ Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania
³⁹ Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
⁴⁰ Physics Department, National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca, Romania
⁴¹ National University of Science and Technology Politechnica, Bucharest, Romania
⁴² West University in Timisoara, Timisoara, Romania
⁴³ Faculty of Physics, University of Bucharest, Bucharest, Romania
⁴⁴ Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovak Republic
⁴⁵ Department of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice, Slovak Republic
⁴⁶ Physics Department, Brookhaven National Laboratory, Upton, NY, USA
⁴⁷ Departamento de Física, y CONICET, Facultad de Ciencias Exactas y Naturales, Instituto de Física de Buenos Aires (IFIBA), Universidad de Buenos Aires, Buenos Aires, Argentina
⁴⁸ California State University, Fresno, CA, USA
⁴⁹ Cavendish Laboratory, University of Cambridge, Cambridge, UK
⁵⁰ Department of Physics, University of Cape Town, Cape Town, South Africa
⁵¹ iThemba Labs, Western Cape, South Africa
⁵² Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg, South Africa
⁵³ National Institute of Physics, University of the Philippines Diliman, Quezon City, Philippines
⁵⁴ Department of Physics, University of South Africa, Pretoria, South Africa
⁵⁵ University of Zululand, KwaDlangezwa, South Africa
⁵⁶ School of Physics, University of the Witwatersrand, Johannesburg, South Africa
⁵⁷ Department of Physics, Carleton University, Ottawa, ON, Canada
⁵⁸ Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies-Université Hassan II, Casablanca, Morocco
⁵⁹ Faculté des Sciences, Université Ibn-Tofail, Kénitra, Morocco
⁶⁰ Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA-Marrakech, Morocco
⁶¹ LPMR, Faculté des Sciences, Université Mohamed Premier, Oujda, Morocco
⁶² Faculté des sciences, Université Mohammed V, Rabat, Morocco
⁶³ Institute of Applied Physics, Mohammed VI Polytechnic University, Ben Guerir, Morocco
⁶⁴ CERN, Geneva, Switzerland
⁶⁵ Affiliated with an Institute Covered by a Cooperation Agreement with CERN, Geneva, Switzerland
⁶⁶ Affiliated with an International Laboratory Covered by a Cooperation Agreement with CERN, Geneva, Switzerland
⁶⁷ Enrico Fermi Institute, University of Chicago, Chicago, IL, USA
⁶⁸ LPC, Université Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand, France
⁶⁹ Nevis Laboratory, Columbia University, Irvington, NY, USA
⁷⁰ Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
⁷¹ Dipartimento di Fisica, Università della Calabria, Rende, Italy
⁷² INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Frascati, Italy
⁷³ Physics Department, Southern Methodist University, Dallas, TX, USA
⁷⁴ Physics Department, University of Texas at Dallas, Richardson, TX, USA
⁷⁵ National Centre for Scientific Research “Demokritos”, Agia Paraskevi, Greece
⁷⁶ Department of Physics, Stockholm University, Stockholm, Sweden
⁷⁷ Oskar Klein Centre, Stockholm, Sweden
⁷⁸ Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen, Germany
⁷⁹ Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany
⁸⁰ Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany
⁸¹ Department of Physics, Duke University, Durham, NC, USA
⁸² SUPA-School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
⁸³ INFN e Laboratori Nazionali di Frascati, Frascati, Italy
⁸⁴ Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
⁸⁵ II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany
⁸⁶ Département de Physique Nucléaire et Corpusculaire, Université de Genève, Geneva, Switzerland
⁸⁷ Dipartimento di Fisica, Università di Genova, Genoa, Italy
⁸⁸ INFN Sezione di Genova, Genoa, Italy
⁸⁹ II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany
⁹⁰ SUPA-School of Physics and Astronomy, University of Glasgow, Glasgow, UK
⁹¹ LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France
⁹² Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, MA, USA
⁹³ Department of Modern Physics and State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, China
⁹⁴ Institute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao, China
⁹⁵ School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE), SKLPPC, Shanghai, China
⁹⁶ Tsung-Dao Lee Institute, Shanghai, China
⁹⁷ School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, China
⁹⁸ Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
⁹⁹ Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
¹⁰⁰ Department of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
¹⁰¹ Department of Physics, University of Hong Kong, Hong Kong, China
¹⁰² Department of Physics and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
¹⁰³ Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
¹⁰⁴ IJCLab, Université Paris-Saclay, CNRS/IN2P3, 91405, Orsay, France
¹⁰⁵ Centro Nacional de Microelectrónica (IMB-CNM-CSIC), Barcelona, Spain
¹⁰⁶ Department of Physics, Indiana University, Bloomington, IN, USA
¹⁰⁷ INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy
¹⁰⁸ ICTP, Trieste, Italy
¹⁰⁹ Dipartimento Politecnico di Ingegneria e Architettura, Università di Udine, Udine, Italy
¹¹⁰ INFN Sezione di Lecce, Lecce, Italy
¹¹¹ Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy
¹¹² INFN Sezione di Milano, Milan, Italy
¹¹³ Dipartimento di Fisica, Università di Milano, Milan, Italy
¹¹⁴ INFN Sezione di Napoli, Naples, Italy
¹¹⁵ Dipartimento di Fisica, Università di Napoli, Naples, Italy
¹¹⁶ INFN Sezione di Pavia, Pavia, Italy
¹¹⁷ Dipartimento di Fisica, Università di Pavia, Pavia, Italy
¹¹⁸ INFN Sezione di Pisa, Pisa, Italy
¹¹⁹ Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy
¹²⁰ INFN Sezione di Roma, Rome, Italy
¹²¹ Dipartimento di Fisica, Sapienza Università di Roma, Rome, Italy
¹²² INFN Sezione di Roma Tor Vergata, Rome, Italy
¹²³ Dipartimento di Fisica, Università di Roma Tor Vergata, Rome, Italy
¹²⁴ INFN Sezione di Roma Tre, Rome, Italy
¹²⁵ Dipartimento di Matematica e Fisica, Università Roma Tre, Rome, Italy
¹²⁶ INFN-TIFPA, Povo, Italy
¹²⁷ Università degli Studi di Trento, Trento, Italy
¹²⁸ Universität Innsbruck, Department of Astro and Particle Physics, Innsbruck, Austria
¹²⁹ University of Iowa, Iowa City, IA, USA
¹³⁰ Department of Physics and Astronomy, Iowa State University, Ames, IA, USA
¹³¹ Istinye University, Sariyer, Istanbul, Türkiye
¹³² Departamento de Engenharia Elétrica, Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, Brazil
¹³³ Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil
¹³⁴ Instituto de Física, Universidade de São Paulo, São Paulo, Brazil
¹³⁵ Rio de Janeiro State University, Rio de Janeiro, Brazil
¹³⁶ KEK, High Energy Accelerator Research Organization, Tsukuba, Japan
¹³⁷ Graduate School of Science, Kobe University, Kobe, Japan
¹³⁸ Faculty of Physics and Applied Computer Science, AGH University of Krakow, Krakow, Poland
¹³⁹ Marian Smoluchowski Institute of Physics, Jagiellonian University, Krakow, Poland
¹⁴⁰ Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland
¹⁴¹ Faculty of Science, Kyoto University, Kyoto, Japan
¹⁴² Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka, Japan
¹⁴³ Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina
¹⁴⁴ Physics Department, Lancaster University, Lancaster, UK
¹⁴⁵ Oliver Lodge Laboratory, University of Liverpool, Liverpool, UK
¹⁴⁶ Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana, Slovenia
¹⁴⁷ School of Physics and Astronomy, Queen Mary University of London, London, UK
¹⁴⁸ Department of Physics, Royal Holloway University of London, Egham, UK
¹⁴⁹ Department of Physics and Astronomy, University College London, London, UK
¹⁵⁰ Louisiana Tech University, Ruston, LA, USA
¹⁵¹ Fysiska Institutionen, Lunds Universitet, Lund, Sweden
¹⁵² Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spain
¹⁵³ Institut für Physik, Universität Mainz, Mainz, Germany
¹⁵⁴ School of Physics and Astronomy, University of Manchester, Manchester, UK
¹⁵⁵ CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France
¹⁵⁶ Department of Physics, University of Massachusetts, Amherst, MA, USA
¹⁵⁷ Department of Physics, McGill University, Montreal, QC, Canada
¹⁵⁸ School of Physics, University of Melbourne, Victoria, Australia
¹⁵⁹ Department of Physics, University of Michigan, Ann Arbor, MI, USA
¹⁶⁰ Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA
¹⁶¹ Group of Particle Physics, University of Montreal, Montreal, QC, Canada
¹⁶² Fakultät für Physik, Ludwig-Maximilians-Universität München, Munich, Germany
¹⁶³ Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Munich, Germany
¹⁶⁴ Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan
¹⁶⁵ Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA
¹⁶⁶ Institute for Mathematics, Astrophysics and Particle Physics, Radboud University/Nikhef, Nijmegen, The Netherlands
¹⁶⁷ Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, The Netherlands
¹⁶⁸ Department of Physics, Northern Illinois University, DeKalb, IL, USA
¹⁶⁹ New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
¹⁷⁰ University of Sharjah, Sharjah, United Arab Emirates
¹⁷¹ Department of Physics, New York University, New York, NY, USA
¹⁷² Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan
¹⁷³ Ohio State University, Columbus, OH, USA
¹⁷⁴ Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK, USA
¹⁷⁵ Department of Physics, Oklahoma State University, Stillwater, OK, USA
¹⁷⁶ Joint Laboratory of Optics, Palacký University, Olomouc, Czech Republic
¹⁷⁷ Institute for Fundamental Science, University of Oregon, Eugene, OR, USA
¹⁷⁸ Graduate School of Science, Osaka University, Osaka, Japan
¹⁷⁹ Department of Physics, University of Oslo, Oslo, Norway
¹⁸⁰ Department of Physics, Oxford University, Oxford, UK
¹⁸¹ LPNHE, Sorbonne Université, Université Paris Cité, CNRS/IN2P3, Paris, France
¹⁸² Department of Physics, University of Pennsylvania, Philadelphia, PA, USA
¹⁸³ Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, USA
¹⁸⁴ Laboratório de Instrumentação e Física Experimental de Partículas-LIP, Lisbon, Portugal
¹⁸⁵ Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
¹⁸⁶ Departamento de Física, Universidade de Coimbra, Coimbra, Portugal
¹⁸⁷ Centro de Física Nuclear da Universidade de Lisboa, Lisbon, Portugal
¹⁸⁸ Departamento de Física, Universidade do Minho, Braga, Portugal
¹⁸⁹ Departamento de Física Teórica y del Cosmos, Universidad de Granada, Granada, Spain
¹⁹⁰ Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
¹⁹¹ Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
¹⁹² Czech Technical University in Prague, Prague, Czech Republic
¹⁹³ Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
¹⁹⁴ Particle Physics Department, Rutherford Appleton Laboratory, Didcot, UK
¹⁹⁵ IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
¹⁹⁶ Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA, USA
¹⁹⁷ Departamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
¹⁹⁸ Millennium Institute for Subatomic physics at high energy frontier (SAPHIR), Santiago, Chile
¹⁹⁹ Instituto de Investigación Multidisciplinario en Ciencia y Tecnología, y Departamento de Física, Universidad de La Serena, La Serena, Chile
²⁰⁰ Department of Physics, Universidad Andres Bello, Santiago, Chile
²⁰¹ Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
²⁰² Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
²⁰³ Department of Physics, University of Washington, Seattle, WA, USA
²⁰⁴ Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
²⁰⁵ Department of Physics, Shinshu University, Nagano, Japan
²⁰⁶ Department Physik, Universität Siegen, Siegen, Germany
²⁰⁷ Department of Physics, Simon Fraser University, Burnaby, BC, Canada
²⁰⁸ SLAC National Accelerator Laboratory, Stanford, CA, USA
²⁰⁹ Department of Physics, Royal Institute of Technology, Stockholm, Sweden
²¹⁰ Departments of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA
²¹¹ Department of Physics and Astronomy, University of Sussex, Brighton, UK
²¹² School of Physics, University of Sydney, Sydney, Australia
²¹³ Institute of Physics, Academia Sinica, Taipei, Taiwan
²¹⁴ E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia
²¹⁵ High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia
²¹⁶ University of Georgia, Tbilisi, Georgia
²¹⁷ Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel
²¹⁸ Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
²¹⁹ Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
²²⁰ International Center for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo, Japan
²²¹ Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
²²² Department of Physics, University of Toronto, Toronto, ON, Canada
²²³ TRIUMF, Vancouver, BC, Canada
²²⁴ Department of Physics and Astronomy, York University, Toronto, ON, Canada
²²⁵ Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
²²⁶ Department of Physics and Astronomy, Tufts University, Medford, MA, USA
²²⁷ United Arab Emirates University, Al Ain, United Arab Emirates
²²⁸ Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
²²⁹ Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden
²³⁰ Department of Physics, University of Illinois, Urbana, IL, USA
²³¹ Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia-CSIC, Valencia, Spain
²³² Department of Physics, University of British Columbia, Vancouver, BC, Canada
²³³ Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
²³⁴ Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
²³⁵ Department of Physics, University of Warwick, Coventry, UK
²³⁶ Waseda University, Tokyo, Japan
²³⁷ Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
²³⁸ Department of Physics, University of Wisconsin, Madison, WI, USA
²³⁹ Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany
²⁴⁰ Department of Physics, Yale University, New Haven, CT, USA
²⁴¹ Affiliated with an Institute Covered by a Cooperation Agreement with CERN, Geneva, Switzerland
²⁴² An-Najah National University, Nablus, Palestine
²⁴³ Borough of Manhattan Community College, City University of New York, New York, NY, USA
²⁴⁴ Center for High Energy Physics, Peking University, Beijing, China
²⁴⁵ Center for Interdisciplinary Research and Innovation (CIRI-AUTH), Thessaloniki, Greece
²⁴⁶ Centro Studi e Ricerche Enrico Fermi, Rome, Italy
²⁴⁷ CERN, Geneva, Switzerland
²⁴⁸ Département de Physique Nucléaire et Corpusculaire, Université de Genève, Geneva, Switzerland
²⁴⁹ Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona, Spain
²⁵⁰ Department of Financial and Management Engineering, University of the Aegean, Chios, Greece
²⁵¹ Department of Physics, Ben Gurion University of the Negev, Beer Sheva, Israel
²⁵² Department of Physics, California State University, Sacramento, USA
²⁵³ Department of Physics, King’s College London, London, UK
²⁵⁴ Department of Physics, Stanford University, Stanford, CA, USA
²⁵⁵ Department of Physics, University of Fribourg, Fribourg, Switzerland
²⁵⁶ Department of Physics, University of Thessaly, Thessaly, Greece
²⁵⁷ Department of Physics, Westmont College, Santa Barbara, USA
²⁵⁸ Hellenic Open University, Patras, Greece
²⁵⁹ Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain
²⁶⁰ Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany
²⁶¹ Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Sofia, Bulgaria
²⁶² Institute of Applied Physics, Mohammed VI Polytechnic University, Ben Guerir, Morocco
²⁶³ , Institute of Particle Physics (IPP), Canada
²⁶⁴ Institute of Physics and Technology, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
²⁶⁵ Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan
²⁶⁶ Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia
²⁶⁷ L2IT, Université de Toulouse, CNRS/IN2P3, UPS, Toulouse, France
²⁶⁸ Lawrence Livermore National Laboratory, Livermore, USA
²⁶⁹ National Institute of Physics, University of the Philippines Diliman, Quezon City, Philippines
²⁷⁰ Technical University of Munich, Munich, Germany
²⁷¹ The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing, China
²⁷² TRIUMF, Vancouver, BC, Canada
²⁷³ Università di Napoli Parthenope, Naples, Italy
²⁷⁴ University of Chinese Academy of Sciences (UCAS), Beijing, China
²⁷⁵ Department of Physics, University of Colorado Boulder, Boulder, CO, USA
²⁷⁶ Washington College, Chestertown, MD, USA
²⁷⁷ Physics Department, Yeditepe University, Istanbul, Türkiye
²⁷⁸ CERN, 1211 Geneva 23, Switzerland

^a atlas.publications@cern.ch

Received: 26 October 2023
Accepted: 10 March 2024
Published online: 3 May 2024

Abstract

Clusters of topologically connected calorimeter cells around cells with large absolute signal-to-noise ratio (topo-clusters) are the basis for calorimeter signal reconstruction in the ATLAS experiment. Topological cell clustering has proven performant in LHC Runs 1 and 2. It is, however, susceptible to out-of-time pile-up of signals from soft collisions outside the 25 ns proton-bunch-crossing window associated with the event’s hard collision. To reduce this effect, a calorimeter-cell timing criterion was added to the signal-to-noise ratio requirement in the clustering algorithm. Multiple versions of this criterion were tested by reconstructing hadronic signals in simulated events and Run 2 ATLAS data. The preferred version is found to reduce the out-of-time pile-up jet multiplicity by for jet  GeV and by for jet  GeV, while not disrupting the reconstruction of hadronic signals of interest, and improving the jet energy resolution by up to 5% for  GeV. Pile-up is also suppressed for other physics objects based on topo-clusters (electrons, photons, -leptons), reducing the overall event size on disk by about in early Run 3 pile-up conditions. Offline reconstruction for Run 3 includes the timing requirement.