https://doi.org/10.1140/epjc/s10052-024-13077-x
Regular Article - Experimental Physics
Measurement of the background in the CMS muon detector in -collisions at
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Vrije Universiteit Brussel, Brussel, Belgium
2
Université Libre de Bruxelles, Bruxelles, Belgium
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Universiteit Gent, Gent, Belgium
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Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil
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Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
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Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria
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University of Sofia, Sofia, Bulgaria
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Instituto De Alta Investigación, Universidad de Tarapacá, Arica, Chile
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Institute of High Energy Physics of the Chinese Academy of Sciences, Beijing, China
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State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China
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Sun Yat-Sen University, Guangzhou, China
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Universidad de Los Andes, Bogota, Colombia
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Universidad de Antioquia, Medellin, Colombia
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Academy of Scientific Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt
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Center for High Energy Physics (CHEP-FU), Fayoum University, El-Fayoum, Egypt
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Institut de Physique des 2 Infinis de Lyon, Villeurbanne, France
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Georgian Technical University, Tbilisi, Georgia
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RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany
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Karlsruher Institut für Technologie, Karlsruhe, Germany
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Institute of Nuclear Research ATOMKI, Debrecen, Hungary
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Institute of Physics, University of Debrecen, Debrecen, Hungary
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Panjab University, Chandigarh, India
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University of Delhi, Delhi, India
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Saha Institute of Nuclear Physics, Kolkata, India
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Institute for Research in Fundamental Sciences, Teheran, Iran
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INFN Sezione di Bari, Università di Bari, Politecnico di Bari, Bari, Italy
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INFN Sezione di Bologna, Università di Bologna, Bologna, Italy
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INFN Laboratori Nazionali di Frascati, Frascati, Italy
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INFN Sezione di Napoli, Università di Napoli ‘Federico II’, Napoli, Italy; Università della Basilicata, Potenza, Italy; Università G. Marconi, Rome, Italy
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INFN Sezione di Padova, Università di Padova, Padova, Italy; Università di Trento, Trento, Italy
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INFN Sezione di Pavia, Università di Pavia, Pavia, Italy
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INFN Sezione di Torino, Università di Torino, Torino, Italy; Università del Piemonte Orientale, Novara, Italy
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Hanyang University, Seoul, Korea
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Korea University, Seoul, Korea
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Kyung Hee University, Department of Physics, Seoul, Korea
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Seoul National University, Seoul, Korea
37
University of Seoul, Seoul, Korea
38
Sungkyunkwan University, Suwon, Korea
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College of Engineering and Technology, American University of the Middle East (AUM), Dasman, Kuwait
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Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
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Universidad Iberoamericana, Mexico City, Mexico
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Benemerita Universidad Autonoma de Puebla, Puebla, Mexico
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National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan
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Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
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Universidad Autónoma de Madrid, Madrid, Spain
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Universidad de Oviedo, Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA), Oviedo, Spain
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University of Colombo, Colombo, Sri Lanka
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University of Ruhuna, Department of Physics, Matara, Sri Lanka
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CERN, European Organization for Nuclear Research, Geneva, Switzerland
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Boston University, Boston, MA, USA
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University of California, Davis, Davis, CA, USA
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University of California, Los Angeles, CA, USA
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University of California, Riverside, Riverside, CA, USA
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University of California, Santa Barbara-Department of Physics, Santa Barbara, CA, USA
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University of Florida, Gainesville, FL, USA
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Florida Institute of Technology, Melbourne, FL, USA
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Massachusetts Institute of Technology, Cambridge, MA, USA
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Northeastern University, Boston, MA, USA
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Northwestern University, Evanston, IL, USA
60
The Ohio State University, Columbus, OH, USA
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Rice University, Houston, TX, USA
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Texas A &M University, College Station, TX, USA
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Wayne State University, Detroit, MI, USA
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University of Wisconsin-Madison, Madison, WI, USA
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Authors affiliated with an institute or an international laboratory covered by a cooperation agreement with CERN, Geneva, Switzerland
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Ghent University, Ghent, Belgium
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Now at Universidad de Antioquia, Medellin, Colombia
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Now at University of Wisconsin-Madison, Madison, Wisconsin, USA
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Cairo University, Gizah, Egypt
70
Helwan University, Cairo, Egypt
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Now at Zewail City of Science and Technology, Zewail, Egypt
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Suez University, Suez, Egypt
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Now at British University in Egypt, Cairo, Egypt
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Ain Shams University, Cairo, Egypt
75
Sultan Qaboos University, Muscat, Oman
76
an institute or an international laboratory covered by a cooperation agreement with CERN, Geneva, Switzerland
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The University of the State of Amazonas, Manaus, Brazil
78
Now at Institute for Research in Fundamental Sciences, Teheran, Iran
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Faculty of Informatics, University of Debrecen, Debrecen, Hungary
80
Now at CERN, European Organization for Nuclear Research, Geneva, Switzerland
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Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Bologna, Italy
82
Eastern Mennonite University, Harrisonburg, VA, USA
83
Università degli Studi Guglielmo Marconi, Rome, Italy
84
Scuola Superiore Meridionale, Università di Napoli ‘Federico II’, Naples, Italy
85
CERN, European Organization for Nuclear Research, Geneva, Switzerland
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Laboratori Nazionali di Legnaro dell’INFN, Legnaro, Italy
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Now at INFN Sezione di Pisa e Università di Pisa, Pisa, Italy
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Now at Gran Sasso Science Institute, L’Aquila, Italy
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Now at Imperial College, London, UK
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Trincomalee Campus, Eastern University, Nilaveli, Sri Lanka
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Now at Max Planck Institute for Physics (Werner Heisenberg Institute), Munich, Germany
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Now at Argonne National Laboratory, Lemont, IL, USA
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Now at Karlsruhe Institute of Technology, Karlsruhe, Germany
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Now at Purdue University, West Lafayette, IN, USA
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Now at Activision, Santa Monica, CA, USA
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Now at HRL Laboratories, Malibu, CA, USA
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Now at Tsung-Dao Lee Institute, Shanghai, China
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Texas A &M University at Qatar, Doha, Qatar
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Kyungpook National University, Daegu, Korea
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Northeastern University, Boston, MA, USA
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CERN, 1211 Geneva 23, Switzerland
Received:
19
April
2024
Accepted:
1
July
2024
Published online:
27
September
2024
The CMS detector, including its muon system, has been operating at the CERN LHC in increasingly challenging conditions for about 15 years. The muon detector was designed to provide excellent triggering and track reconstruction for muons produced in proton–proton collisons at an instantaneous luminosity () of cms. During the Run 2 data-taking period (2015–2018), the LHC achieved an instantaneous luminosity of twice its design value, resulting in larger background rates and making the efficient detection of muons more difficult. While some backgrounds result from natural radioactivity, cosmic rays, and interactions of the circulating protons with residual gas in the beam pipe, the dominant source of background hits in the muon system arises from proton–proton interactions themselves. Charged hadrons leaving the calorimeters produce energy deposits in the muon chambers. In addition, high-energy particles interacting in the hadron calorimeter and forward shielding elements generate thermal neutrons, which leak out of the calorimeter and shielding structures, filling the CMS cavern. We describe the method used to measure the background rates in the various muon subsystems. These rates, in conjunction with simulations, can be used to estimate the expected backgrounds in the High-Luminosity LHC. This machine will run for at least 10 years starting in 2029 reaching an instantaneous luminosity of and increasing ultimately to . These background estimates have been a key ingredient for the planning and design of the muon detector upgrade.
A. Benvenuti, A. Vorobyev: Deceased.
© The Author(s) 2024
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