Physics Briefing Book

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Physics Briefing Book CERN-ESU-004 10 January 2020 Physics Briefing Book Input for the European Strategy for Particle Physics Update 2020 ; Electroweak Physics: Richard Keith Ellis1, Beate Heinemann2 3 (Conveners) Jorge de Blas4;5, Maria Cepeda6, Christophe Grojean2;7, Fabio Maltoni8;9, Aleandro Nisati10, Elisabeth Petit11, Riccardo Rattazzi12, Wouter Verkerke13 (Contributors) Strong Interactions: Jorgen D’Hondt14, Krzysztof Redlich15 (Conveners) Anton Andronic16, Ferenc Siklér17 (Scientific Secretaries) Nestor Armesto18, Daniël Boer19, David d’Enterria20, Tetyana Galatyuk21, Thomas Gehrmann 22, Klaus Kirch23, Uta Klein24, Jean-Philippe Lansberg25, Gavin P. Salam26, Gunar Schnell27, Johanna Stachel28, Tanguy Pierog29, Hartmut Wittig30, Urs Wiedemann20(Contributors) Flavour Physics: Belen Gavela31, Antonio Zoccoli32 (Conveners) Sandra Malvezzi33, Ana M. Teixeira34, Jure Zupan35 (Scientific Secretaries) Daniel Aloni36, Augusto Ceccucci20, Avital Dery36, Michael Dine37, Svetlana Fajfer38, Stefania Gori37, Gudrun Hiller39, Gino Isidori22, Yoshikata Kuno40, Alberto Lusiani41, Yosef Nir36, Marie-Helene Schune42, Marco Sozzi43, Stephan Paul44, Carlos Pena31 (Contributors) ; Neutrino Physics & Cosmic Messengers: Stan Bentvelsen45, Marco Zito46 47 (Conveners) Albert De Roeck 20, Thomas Schwetz29 (Scientific Secretaries) Bonnie Fleming48, Francis Halzen49, Andreas Haungs29, Marek Kowalski2, Susanne Mertens44, Mauro Mezzetto5, Silvia Pascoli50, Bangalore Sathyaprakash51, Nicola Serra22 (Contributors) ; Beyond the Standard Model: Gian F. Giudice20, Paris Sphicas20 52 (Conveners) Juan Alcaraz Maestre6, Caterina Doglioni53, Gaia Lanfranchi20;54, Monica D’Onofrio24, Matthew McCullough20, Gilad Perez36, Philipp Roloff20, Veronica Sanz55, Andreas Weiler44, Andrea Wulzer4;12;20 (Contributors) Dark Matter and Dark Sector: Shoji Asai56, Marcela Carena57 (Conveners) Babette Döbrich20, Caterina Doglioni53, Joerg Jaeckel28, Gordan Krnjaic57, Jocelyn Monroe58, Konstantinos Petridis59, Christoph Weniger60 (Scientific Secretaries/Contributors) Accelerator Science and Technology: Caterina Biscari61, Leonid Rivkin62 (Conveners) Philip Burrows26, Frank Zimmermann20 (Scientific Secretaries) Michael Benedikt20, Pierluigi Campana54, Edda Gschwendtner20, Erk Jensen20, Mike Lamont20, arXiv:1910.11775v2 [hep-ex] 10 Jan 2020 Wim Leemans2, Lucio Rossi20, Daniel Schulte20, Mike Seidel62, Vladimir Shiltsev63, Steinar Stapnes20, Akira Yamamoto20;64 (Contributors) Instrumentation and Computing: Xinchou Lou65, Brigitte Vachon66 (Conveners) Roger Jones67, Emilia Leogrande20 (Scientific Secretaries) Ian Bird20, Simone Campana20, Ariella Cattai20, Didier Contardo68, Cinzia Da Via69, Francesco Forti70, Maria Girone20, Matthias Kasemann2, Lucie Linssen20, Felix Sefkow2, Graeme Stewart20(Contributors) Editors: Halina Abramowicz71, Roger Forty20, and the Conveners 1 IPPP, University of Durham, UK 49 Winsconsin University, US 2 DESY, Hamburg, Germany 50 Durham University, UK 3 Albert-Ludwigs-Universität Freiburg, Germany 51 Pennsylvania State University, US 4 University of Padova, Italy 52 NKUA, Athens, Greece 5 INFN Sezione di Padova, Italy 53 Lund University, Sweden 6 CIEMAT, Madrid, Spain 54 INFN-LNF, Frascati, Italy 7 Humboldt-Universität, Berlin, Germany 55 8 University of Sussex, UK Université catholique de Louvain, Belgium 56 9 University of Tokyo, Japan Università di Bologna and INFN, Bologna, Italy 57 FNAL and University of Chicago, US 10 INFN Roma, Rome, Italy 58 Royal Holloway, University of London, UK 11 Aix Marseille University, CNRS/IN2P3, CPPM, 59 University of Bristol, UK Marseille, France 60 12 EPFL, Lausanne, Switzerland GRAPPA, University of Amsterdam, Netherlands 61 13 NIKHEF and University of Amsterdam, Netherlands ALBA Cells, Barcelona, Spain 62 14 IIHE, Vrije Universiteit Brussel, Belgium PSI, Villigen, Switzerland 63 15 University of Wrocław, Poland FNAL, Batavia, US 64 16 Westfälische Wilhelms-Universität Münster, KEK, Tsukuba, Japan 65 Germany IHEP, China 66 17 Wigner Research Centre for Physics, Budapest, McGill University, Canada Hungary 67 University of Lancaster, UK 18 IGFAE, Universidade de Santiago de Compostela, 68 IN2P3, France Spain 69 University of Manchester, UK 19 University of Groningen, The Netherlands 70 INFN and University of Pisa, Italy 20 CERN, Geneva, Switzerland 71 Tel Aviv University, Israel 21 Technische Universität Darmstadt, Germany 22 Universität Zürich, Switzerland 23 ETH Zürich and PSI, Villigen, Switzerland 24 University of Liverpool, UK 25 IPNO, Université Paris-Saclay, Univ. Paris-Sud, CNRS/IN2P3, France 26 University of Oxford, UK 27 University of the Basque Country UPV/EHU, Bilbao, Spain 28 Universität Heidelberg, Germany 29 KIT, Institut für Kernphysik, Karlsruhe, Germany 30 Universität Mainz, Germany 31 Universidad Autonoma de Madrid, Spain 32 INFN and Universita di Bologna, Italy 33 INFN Milano-Bicocca, Milano, Italy 34 Laboratoire de Physique de Clermont, CNRS/IN2P3, University Clermont Auvergne, France 35 University of Cincinnati, Ohio, US 36 Weizmann Institute of Science, Rehovot, Israel 37 University of California, Santa Cruz, US 38 University of Ljubljana and J. Stefan Institute, Ljubljana, Slovenia 39 Technische Uinversität Dortmund, Germany 40 Osaka University, Japan 41 Scuola Normale Superiore and INFN Pisa, Italy 42 LAL Orsay, Paris, France 43 University of Pisa, Italy 44 Technische Universität München, Germany 45 NIKHEF, Netherlands 46 IRFU/DPhP CEA Saclay, France 47 LPNHE, Paris, France 48 Yale University, US ii Contents 1 Introduction 1 2 Theoretical overview 16 3 Electroweak Physics 24 3.1 Introduction . 24 3.2 Future prospects . 30 3.3 Summary and conclusions . 41 4 Strong Interactions 43 4.1 State-of-the-art . 43 4.2 Hadronic structure . 46 4.3 Electron-proton collisions (LHeC, EIC, FCC) . 46 4.4 Hot and dense QCD . 50 4.5 Precision QCD . 53 4.6 QCD and other disciplines . 62 4.7 Overview and perspectives for QCD . 64 5 Flavour Physics 65 5.1 Introduction/Theory of Flavour . 65 5.2 Light sector: spectrum below GeV (short-, mid- and long-term) . 68 5.3 Heavy sector (short-, mid- and long-term) . 74 5.4 Flavour and dark sectors (short-, mid- and long-term) . 83 5.5 The CKM matrix elements: prospects . 85 5.6 Conclusions . 87 6 Neutrino Physics 90 6.1 Introduction . 90 6.2 Present knowledge of neutrino mixing parameters . 91 6.3 Measurements of neutrino oscillation parameters . 92 6.4 Determination of neutrino mass and nature . 100 6.5 Search for new neutrino states . 102 6.6 Conclusions . 104 7 Cosmic Messengers 105 7.1 Ultra-High Energy charged particles . 106 7.2 High-Energy gamma rays . 107 7.3 Ultra High Energy neutrinos . 108 7.4 Gravitational waves . 109 7.5 Multimessenger astroparticle physics . 111 7.6 Synergies with HEP . 111 iii 8 Beyond the Standard Model 113 8.1 Introduction . 113 8.2 Electroweak symmetry breaking and new resonances . 114 8.3 Supersymmetry . 118 8.4 Extended Higgs sectors and high-energy flavour dynamics . 125 8.5 Dark Matter . 129 8.6 Feebly-interacting particles . 132 8.7 Summary and conclusions . 137 9 Dark Matter and Dark Sectors 142 9.1 Introduction . 142 9.2 Astrophysical Probes of Dark Matter . 144 9.3 Dark matter and Dark sectors at Colliders . 147 9.4 DM and DS at beam-dump and fixed-target experiments . 151 9.5 Axions and ALPs . 156 9.6 Conclusions . 160 10 Accelerator Science and Technology 162 10.1 Present state of accelerator technology for HEP . 162 10.2 Technologies for electroweak sector . 165 10.3 Path towards highest energies . 171 10.4 Muon Colliders . 173 10.5 Plasma acceleration . 175 10.6 Accelerators Beyond Colliders . 178 10.7 Energy management . 182 10.8 The role of National Laboratories in the European Strategy . 184 10.9 Complementarities and synergies with other fields . 185 11 Instrumentation and Computing 187 11.1 Particle physics instrumentation . 187 11.2 Computing and software for particle physics . 199 11.3 Interplay between instrumentation and computing . 203 11.4 Developing and preserving knowledge and expertise . 203 11.5 Summary of key points . 205 Appendices 205 A Glossary . 206 B Open Symposium scientific programme . 208 C European Strategy Update contributions . 211 References 215 iv Chapter 1 Introduction The European Particle Physics Strategy Update (EPPSU) process takes a bottom-up approach, whereby the community is first invited to submit proposals (also called inputs) for projects that it would like to see realised in the near-term, mid-term and longer-term future. National in- puts as well as inputs from National Laboratories are also an important element of the process. All these inputs are then reviewed by the Physics Preparatory Group (PPG), whose role is to organize a Symposium around the submitted ideas and to prepare a community discussion on the importance and merits of the various proposals. The results of these discussions are then concisely summarised in this Briefing Book, prepared by the Conveners, assisted by Scientific Secretaries, and with further contributions provided by the Contributors listed on the title page. This constitutes the basis for the considerations of the European Strategy Group (ESG), con- sisting of scientific delegates from CERN Member States, Associate Member States, directors of major European laboratories, representatives of various European organizations as well as invitees from outside the European Community. The ESG has the mission to formulate the European Strategy Update for the consideration and approval of the CERN Council. For the 2020 EPPSU, the call for inputs was issued at the end of February 2018 with the deadline
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