detectors, whiletheUA1collaborationwasthe prototype ofthenowwellaccepted very large international scienti?c collaborations. Towards the end of this meeting, we shall look forward to the future programme of CERN. We are able to do so with the con?dence engendered by our discoveries of long ago. LucianoMaiani (CERNDirectorGeneral) CERNpressrelease 1 Communique depresseduCERN 2 Welcome L. Maiani 5 ThemakingoftheStandardModel S. Weinberg 9 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 CERN scontributiontoacceleratorsandbeams G. Brianti 25 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2 Magnetic horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 3 PS Booster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 4 ISR, ?rst proton--proton collider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 5 SPS collider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 6 LEPandLHC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Thediscoveryofneutralcurrents D. Haidt 41 1 Prolog. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 2 The double challenge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3 Euphoria in March 1973. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 4 The proof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 5 Attack and ?nal victory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 6 Epilog. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Thediscoveryofthe &, apersonalrecollection P. Darriulat 55 1 Preamble. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 2 An announced discovery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 X Contents 3 The proton--antiproton choice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 4 Physics in the limelight and physics in the shade. . . . . . . . . . . . . . . . . . . . . . 59 5 The UA1/UA2 competition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 & physicsatLEP P. Zerwas 73 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 2 -Boson physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 2. 1 The electroweak basis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 2. 2 Top-quark prediction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 2. 3 Quantum chromodynamics QCD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 2. 4 Three families in the Standard Model . . . . . . . . . . . . . . . . . . . . . . . . . . 81 2. 5 Gauge coupling uni?cation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 3 -Boson physics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 4 Higgs mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 4. 1 Virtual Higgs mass estimate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 4. 2 Real Higgs mass bound. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 PhysicsattheLHC J. Ellis 89 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 2 The quest for the Higgs boson . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ."

This book, comprising contributions presented at the XIX Edoardo Amaldi Conference, examines important aspects of international cooperation aimed at enhancing nuclear safety, security, safeguards (the "3S"), and non-proliferation, thereby assisting in the development and maintenance of the verification regime and progress toward a nuclear weapon-free world. The Conference served as a forum where eminent scientists, diplomats, and policymakers could compare national perspectives and update international collaborations. The book opens by addressing the political, institutional, and legal dimensions of the 3S and non-proliferation; current challenges are discussed and attempts made to identify possible solutions and future improvements. Subsequent sections consider scientific developments that can contribute to increased effectiveness in the implementation of international regimes, particularly in critical areas, technology foresight, and the ongoing evaluation of current capabilities. The closing sections discuss scientific and technical challenges to the effective implementation of the 3S approach and the role of international cooperation and scientific community actions in leading the world toward peace and security.

This open access book is based on the conference organised by Accademia dei Lincei and the US National Academy of Sciences and supported by the Italian Ministero degli Affari Esteri. It was attended by about 60 scientists and researchers from 13 countries, including, besides Europe, Iran, Israel, Iraq, Pakistan, India, Japan, Russian Federation and the USA. In an international scenario shaken by the uncertainties of the pandemic and the war between Russia and Ukraine, dialogue and scientific collaboration are confirmed to be precious tools to enhance nuclear safety, security and non-proliferation. The urgency to open peace discussions in Ukraine was emphasised by all participants, and the belief that science can make an essential contribution to peace construction was reaffirmed. Current challenges (some new, such as autonomous weapons and the use of artificial intelligence for war purposes) are discussed and attempts made to identify possible solutions and future improvements, including in the field of sustainable energy development.

Written by world-leading experts in particle physics, this new book from Luciano Maiani and Omar Benhar, with contributions from the late Nicola Cabibbo, is based on Feynman's path integrals. Key elements of gauge theories are described-Feynman diagrams, gauge-fixing, Faddeev-Popov ghosts-as well as renormalization in Quantum Electrodynamics. Quarks and QCD interactions are introduced. Renormalization group and high momentum behaviour of the coupling constants is discussed in QED and QCD, with asymptotic freedom derived at one-loop. These concepts are related to the Higgs boson and models of grand unification. "... an excellent introduction to the quantum theory of gauge fields and their applications to particle physics. ... It will be an excellent book for the serious student and a good reference for the professional practitioner. Let me add that, scattered through the pages, we can find occasional traces of Nicola Cabibbo's style." -John Iliopoulos, CNRS-Ecole Normale Superieure " ... The volume ends with an illuminating description of the expectation generated by the recent discovery of the Higgs boson, combined with the lack of evidence for super-symmetric particles in the mass range 0.6-1 TeV." -Arturo Menchaca-Rocha, FinstP, Professor of Physics, Mexico's National Autonomous University, Former President of the Mexican Academy of Sciences, Presidential Advisor "...The reader is masterfully guided through the subtleties of the quantum field theory and elementary particle physics from simple examples in Quantum Mechanics to salient details of modern theory." -Mikhail Voloshin, Professor of Physics, University of Minnesota

Get First-Hand Insight from a Contributor to the Standard Model of Particle Physics Written by an award-winning former director-general of CERN and one of the world's leading experts on particle physics, Electroweak Interactions explores the concepts that led to unification of the weak and electromagnetic interactions. It provides the fundamental elements of the theory of compact Lie groups and their representations, enabling a basic understanding of the role of flavor symmetry in particle physics. Understand Conceptual Elements of the Theory of Elementary Particles The book begins with the identification of the weak hadronic current with the isotopic spin current, Yang-Mills theory, and the first electroweak theory of Glashow. It discusses spontaneous breaking of a global symmetry and a local symmetry, covering the Goldstone theorem, Brout-Englert-Higgs mechanism, and the theory of Weinberg and Salam. The author then describes the theory of quarks, quark mixing, the Cabibbo angle, the Glashow-Iliopoulos-Maiani (GIM) mechanism, the theory of Kobayashi and Maskawa, six quark flavors, and CP violation. Delve into Experimental Tests and Unresolved Problems The author goes on to explore some phenomenological topics, such as neutral current interactions of neutrinos and CP violation in the neutral K-meson system. He also highlights how flavor-changing neutral current processes have emerged as probes to reveal the presence of new phenomena at energies not yet accessible with particle accelerators. The book concludes with an explanation of the expected properties of the Higgs boson and the methods adopted for its search. The predictions are also compared with relevant experimental results. View the author's first book in this collection: Relativistic Quantum Mechanics: An Introduction to Relativistic Quantum Fields.

'The editors make a good point in claiming the time has come to upgrade the Standard Model into the aEURO~Standard TheoryaEURO (TM) of particle physics, and I think this book deserves a place in the bookshelves of a broad community, from the scientists and engineers who contributed to the progress of high-energy physics to younger physicists, eager to learn and enjoy the corresponding inside stories.'Carlos LourencoCERN CourierThe book gives a quite complete and up-to-date picture of the Standard Theory with an historical perspective, with a collection of articles written by some of the protagonists of present particle physics. The theoretical developments are described together with the most up-to-date experimental tests, including the discovery of the Higgs Boson and the measurement of its mass as well as the most precise measurements of the top mass, giving the reader a complete description of our present understanding of particle physics.

Get First-Hand Insight from a Contributor to the Standard Model of Particle Physics Written by an award-winning former director-general of CERN and one of the world's leading experts on particle physics, Electroweak Interactions explores the concepts that led to unification of the weak and electromagnetic interactions. It provides the fundamental elements of the theory of compact Lie groups and their representations, enabling a basic understanding of the role of flavor symmetry in particle physics. Understand Conceptual Elements of the Theory of Elementary Particles The book begins with the identification of the weak hadronic current with the isotopic spin current, Yang-Mills theory, and the first electroweak theory of Glashow. It discusses spontaneous breaking of a global symmetry and a local symmetry, covering the Goldstone theorem, Brout-Englert-Higgs mechanism, and the theory of Weinberg and Salam. The author then describes the theory of quarks, quark mixing, the Cabibbo angle, the Glashow-Iliopoulos-Maiani (GIM) mechanism, the theory of Kobayashi and Maskawa, six quark flavors, and CP violation. Delve into Experimental Tests and Unresolved Problems The author goes on to explore some phenomenological topics, such as neutral current interactions of neutrinos and CP violation in the neutral K-meson system. He also highlights how flavor-changing neutral current processes have emerged as probes to reveal the presence of new phenomena at energies not yet accessible with particle accelerators. The book concludes with an explanation of the expected properties of the Higgs boson and the methods adopted for its search. The predictions are also compared with relevant experimental results. View the author's first book in this collection: Relativistic Quantum Mechanics: An Introduction to Relativistic Quantum Fields.

This open access book is based on the conference organised by Accademia dei Lincei and the US National Academy of Sciences and supported by the Italian Ministero degli Affari Esteri. It was attended by about 60 scientists and researchers from 13 countries, including, besides Europe, Iran, Israel, Iraq, Pakistan, India, Japan, Russian Federation and the USA. In an international scenario shaken by the uncertainties of the pandemic and the war between Russia and Ukraine, dialogue and scientific collaboration are confirmed to be precious tools to enhance nuclear safety, security and non-proliferation. The urgency to open peace discussions in Ukraine was emphasised by all participants, and the belief that science can make an essential contribution to peace construction was reaffirmed. Current challenges (some new, such as autonomous weapons and the use of artificial intelligence for war purposes) are discussed and attempts made to identify possible solutions and future improvements, including in the field of sustainable energy development.

Written by world-leading experts in particle physics, this new book from Luciano Maiani and Omar Benhar, with contributions from the late Nicola Cabibbo, is based on Feynman's path integrals. Key elements of gauge theories are described-Feynman diagrams, gauge-fixing, Faddeev-Popov ghosts-as well as renormalization in Quantum Electrodynamics. Quarks and QCD interactions are introduced. Renormalization group and high momentum behaviour of the coupling constants is discussed in QED and QCD, with asymptotic freedom derived at one-loop. These concepts are related to the Higgs boson and models of grand unification. "... an excellent introduction to the quantum theory of gauge fields and their applications to particle physics. ... It will be an excellent book for the serious student and a good reference for the professional practitioner. Let me add that, scattered through the pages, we can find occasional traces of Nicola Cabibbo's style." -John Iliopoulos, CNRS-Ecole Normale Superieure " ... The volume ends with an illuminating description of the expectation generated by the recent discovery of the Higgs boson, combined with the lack of evidence for super-symmetric particles in the mass range 0.6-1 TeV." -Arturo Menchaca-Rocha, FinstP, Professor of Physics, Mexico's National Autonomous University, Former President of the Mexican Academy of Sciences, Presidential Advisor "...The reader is masterfully guided through the subtleties of the quantum field theory and elementary particle physics from simple examples in Quantum Mechanics to salient details of modern theory." -Mikhail Voloshin, Professor of Physics, University of Minnesota

This open access book examines key aspects of international cooperation to enhance nuclear safety, security, safeguards, and nonproliferation, thereby assisting in development and maintenance of the verification regime and fostering progress toward a nuclear weapon-free world. Current challenges are discussed and attempts made to identify possible solutions and future improvements, considering scientific developments that have the potential to increase the effectiveness of implementation of international regimes, particularly in critical areas, technology foresight, and the ongoing evaluation of current capabilities.

This open access book examines key aspects of international cooperation to enhance nuclear safety, security, safeguards, and nonproliferation, thereby assisting in development and maintenance of the verification regime and fostering progress toward a nuclear weapon-free world. Current challenges are discussed and attempts made to identify possible solutions and future improvements, considering scientific developments that have the potential to increase the effectiveness of implementation of international regimes, particularly in critical areas, technology foresight, and the ongoing evaluation of current capabilities.

This book, comprising contributions presented at the XIX Edoardo Amaldi Conference, examines important aspects of international cooperation aimed at enhancing nuclear safety, security, safeguards (the "3S"), and non-proliferation, thereby assisting in the development and maintenance of the verification regime and progress toward a nuclear weapon-free world. The Conference served as a forum where eminent scientists, diplomats, and policymakers could compare national perspectives and update international collaborations. The book opens by addressing the political, institutional, and legal dimensions of the 3S and non-proliferation; current challenges are discussed and attempts made to identify possible solutions and future improvements. Subsequent sections consider scientific developments that can contribute to increased effectiveness in the implementation of international regimes, particularly in critical areas, technology foresight, and the ongoing evaluation of current capabilities. The closing sections discuss scientific and technical challenges to the effective implementation of the 3S approach and the role of international cooperation and scientific community actions in leading the world toward peace and security.

The discoveries of neutral currents and of the W and Z bosons marked a watershed in the history of CERN. They established the validity of the electroweak theory and convinced the physicists of the importance of renormalizable non-Abelian gauge theories of the fundamental interactions. The articles collected in this book have been written by distinguished physicists who contributed in a crucial way to these developments. The book is a historical account of those discoveries and of the construction and the testing of the standard model. It also reports on the future of particle physics and provides an updated status report on the LHC and its detectors being currently built at CERN. The book addresses readers interested in particle physics including the educated public.

This work summarises the salient features of current and planned experiments into multiquark hadrons, describing various inroads to accommodate them within a theoretical framework. At a pedagogical level, authors review the salient aspects of quantum chromodynamics (QCD), the theory of strong interactions, which has been brought to the fore by high-energy physics experiments over recent decades. Compact diquarks as building blocks of a new spectroscopy are presented and confronted with alternative explanations of the XYZ resonances. Ways to distinguish among theoretical alternatives are illustrated, to be tested with the help of high luminosity LHC, electron-positron colliders, and the proposed Tera-Z colliders. Non-perturbative treatments of multiquark hadrons, such as large N expansion, lattice QCD simulations, and predictions about doubly heavy multiquarks are reviewed in considerable detail. With a broad appeal across high-energy physics, this work is pertinent to researchers focused on experiments, phenomenology or lattice QCD.