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This paper gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at CERN, radiation fields at high-energy accelerators, and the radiation monitoring system used at CERN. A short section addresses the ALARA approach used at CERN.
This report presents the proceedings of the Course on Advanced Accelerator Physics organized by the CERN Accelerator School. The course was held in Trondheim, Norway from 18 to 29 August 2013, in collaboration with the Norwegian University of Science and Technology. Its syllabus was based on previous courses and in particular on the course held in Berlin 2003 whose proceedings were published as CERN Yellow Report CERN- 2006-002. The field has seen significant advances in recent years and some topics were presented in a new way and other topics were added. The lectures were supplemented with tutorials on key topics and 14 hours of hands on courses on Optics Design and Corrections, RF Measurement Techniques and Beam Instrumentation and Diagnostics. These courses are a key element of the Advanced Level Course.
Current and future experiments at CERN are reviewed,with emphasis on those relevant to astrophysics and cosmology. These include experiments related to nuclear astrophysics, matter-antimatter asymmetry, dark matter, axions, gravitational waves, cosmic rays, neutrino oscillations, inflation, neutron stars and the quark-gluon plasma. The centrepiece of CERN's future programme is the LHC, but some ideas for perspectives after the LHC are also presented.
Several indicators have pointed to the presence of an Electron Cloud (EC) in some of the CERN accelerators, when operating with closely spaced bunched beams. In particular, spurious signals on the pick ups used for beam detection, pressure rise and beam instabilities were observed at the Proton Synchrotron (PS) during the last stage of preparation of the beams for the Large Hadron Collider (LHC), as well as at the Super Proton Synchrotron (SPS). Since the LHC has started operation in 2009, typical electron cloud phenomena have appeared also in this machine, when running with trains of closely packed bunches (i.e. with spacings below 150ns). Beside the above mentioned indicators, other typical signatures were seen in this machine (due to its operation mode and/or more refined detection possibilities), like heat load in the cold dipoles, bunch dependent emittance growth and degraded lifetime in store and bunch-by-bunch stable phase shift to compensate for the energy loss due to the electron cloud. An overview of the electron cloud status in the different CERN machines (PS, SPS, LHC) will be presented in this paper, with a special emphasis on the dangers for future operation with more
This report contains the proceedings of the Workshop on Accelerator Magnet Superconductor, Design and Optimization (WAMSDO) held at CERN from 15 to 16 January 2013. This fourth edition of the WAMSDO workshop is focussed on aspects related to quench protection.
These proceedings present the lectures given at the twenty-third specialized course organized by the CERN Accelerator School (CAS), the topic being 'Magnets'. The course was held in Bruges, Belgium, from 16 to 25 June 2009. This is the first time this topic has been selected for a specialized course. Taking into account the number of related applications currently in use in accelerators around the world, but, even more important, the worrying decrease in the corresponding expertise in the different laboratories, it was recognized that such a topic should definitively be incorporated into the CAS series of specialized courses. The specific aim of the course was to introduce the participants to the basics of resistive magnet design and its underlying theoretical concepts. The first part of the school dealt with basic introductory courses such as Maxwell's equations for magnets, beam optics, physics and measurement of magnetic materials, the different types of resistive magnets and their respective performance, an introduction to numerical field computation, and a core lecture on basic magnet design. The second part of the course focused more on quality control, the different measurem
This paper reviews the set-up, experimental studies, and beam observations with one or two prototype long-range beam-beam 'wire' compensators in the CERN SPS from 2002 to 2012.
This report contains the Proceedings of the ICFA Mini-Workshop on Beam-Beam Effects in Hadron Colliders held at CERN from 18 to 22 March 2013. It was the first of its kind after the successful start of LHC operation where a vast amount of beam-beam observations emerged. It brought together 58 international experts in the field and the purpose of this workshop was to review the present knowledge in the fields of beam-beam theory, simulations and observations. In the summary session the participants acknowledged the enormous progress made in recent years and the introduction of new concepts and tools. The workshop was concluded by a discussion on future research work with emphasis on the LHC operation and future circular colliders.
These proceedings present the lectures given at the twenty-fourth specialized course organized by the CERN Accelerator School (CAS). The course was held in Ebeltoft, Denmark, from 8-17 June, 2010 in collaboration with Aarhus University, with the topic 'RF for Accelerators' While this topic has been covered by CAS previously, early in the 1990s and again in 2000, it was recognized that recent advances in the field warranted an updated course. Following introductory courses covering the background physics, the course attempted to cover all aspects of RF for accelerators; from RF power generation and transport, through cavity and coupler design, electronics and low level control, to beam diagnostics and RF gymnastics. The lectures were supplemented with several sessions of exercises, which were completed by discussion sessions on the solutions.
The CERN-Latin-American School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lecture notes on the Standard Model of electroweak interactions, flavour physics, neutrino physics, Higgs physics, new physics beyond the standard model, quantum chromodynamics under extreme conditions, cosmology, an introduction to experimental facilities at the high-energy frontier, and practical statistics for particle physicists.
Simon van der Meer was a brilliant scientist and a true giant in the field of accelerators. His seminal contributions to accelerator science are essential to this day in our quest to satisfy the demands of modern particle physics. Whether we are talking of long-baseline neutrino physics or antiproton-proton physics at CERN and Fermilab, or proton-proton physics at the LHC, his techniques and inventions have been a vital and necessary part of modern-day successes. Simon van der Meer and Carlo Rubbia were the first CERN scientists to become Nobel laureates in Physics in 1984. His less well-known contributions spanned a whole range of subjects in accelerator science from magnet design to power supply design, beam measurements, slow beam extraction, sophisticated programs, and controls.
The CERN strategy for future accelerator projects is outlined and the role of the HE-LHC inside this strategy is described.
This document describes the results of a study, aiming to measure the impact of CERN and of its environment on the career of people who worked at the laboratory. The data was collected using two on-line questionnaires, launched in 2016 and 2017, targeting experimentalists and theorists, respectively. The mandate, the methodology followed, the questionnaires and the analysis of the data collected are presented.
These proceedings collate lectures given at the course on Accelerators for Medical Applications, organised by the CERN Accelerator School (CAS). The course was held at the Eventhotel Pyramide, Vösendorf, Austria from 26 May to 5 June, in collaboration with MedAustron. Following introductory lectures on radiobiological and oncological issues, the basic requirements on accelera- tors and beam delivery are reviewed. The medical applications of linear accelerators, cyclotrons and synchrotrons are then be treated in some detail, followed by lectures on the production and use of radioisotopes and a look at some of the acceleration techniques for the future.
These proceedings collate lectures given at the twenty-seventh specialized course organised by the CERN Accelerator School (CAS). The course was held at the Ettore Majorana Foundation and Centre for Scientific Culture (EMFCSC) in Erice, Italy, from 24 April to 4 May 2013. Following recapitulation lectures on basic accelerator physics and superconductivity, the course covered topics related to the design, production and operation of superconducting RF systems and superconducting magnets for accelerators. The participants pursued one of six case studies in order to get 'hands-on' experience of the issues connected with the design of superconducting systems. A series of topical seminars completed the programme.
The CERN-Latin-American School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lectures on quantum field theory, quantum chromodynamics, physics beyond the Standard Model, neutrino physics, flavour physics and CP violation, particle cosmology, high-energy astro-particle physics, and heavy-ion physics, as well as trigger and data acquisition, and commissioning and early physics analysis of the ATLAS and CMS experiments. Also included are write-ups of short review projects performed by the student discussions groups.
This report sums up in two volumes the first 50 years of operation of the CERN Proton Synchrotron. After an introduction on the genesis of the machine, and a description of its magnet and powering systems, the first volume focuses on some of the many innovations in accelerator physics and instrumentation that it has pioneered, such as transition crossing, RF gymnastics, extractions, phase space tomography, or transverse emittance measurement by wire scanners. The second volume describes the other machines in the PS complex: the proton linear accelerators, the PS Booster, the LEP pre-injector, the heavy-ion linac and accumulator, and the antiproton rings.
This report contains the Proceedings of the Joint INFN-Frascati, INFN-Pisa, CERN-LER and EuCARD-AccNet Mini-Workshop on Electron-Cloud Effects, "ECLOUD12", held at La Biodola, Isola d'Elba, from 5 to 9 June 2012. The ECLOUD12 workshop reviewed many recent electron-cloud (EC) observations at existing storage rings, EC predictions for future accelerators, electron-cloud studies at DAFNE, EC mitigation by clearing electrodes and graphite/carbon coatings, modeling of incoherent EC effects, self-consistent simulations, synergies with other communities like the Valencia Space Consortium and the European Space Agency. ECLOUD12 discussed new EC observations at existing machines including LHC, CesrTA, PETRA-3, J-PARC, and FNAL MI; latest experimental efforts to characterize the EC - including EC diagnostics, experimental techniques, mitigation techniques such as coating and conditioning, advanced chemical and physical analyses of various vacuum-chamber surfaces, beam instabilities and emittance growth -; the status of EC physics models and (new, more versatile and additional) simulation codes and their comparison with recently acquired experimental data; and the mitigation requirements and
These proceedings collate lectures given at the twenty-sixth specialized course organised by the CERN Accelerator School (CAS). The course was held in Senec, Slovakia from 29 May to 8 June 2012, in collaboration with the Slovak University of Technology, Bratislava. Following lectures on the background accelerator physics and the fundamental processes underlying the production of particle beams, the course covered the different types of ion sources and associated technological issues, and different applications for which sources are used. The participants pursued one of six case studies in order to get "hands-on" experience of the issues connected with the design of an ion source.
No Abstract of this Colloquium