CHAPTER 1 CERN from the mid-1960s to the late 1970s John KRIGE Contents 1.1 Some preliminaries 7 1.2 The growth in the user population 13 1.3 Machines and beams 18 1.3.1 The Proton Synchrotron 19 1.3.2 The Synchro-Cyclotron 22 1.3.3 The Intersecting Storage Rings 23 1.4 Detectors 26 1.5 The member states 29 Notes 35 (CRHST, CNRS and Cite des Sciences et de I'lndustrie, 75930 Paris, France) 3 Before surveying the years in the Ufe of CERN covered by this book, let us pause for a moment to consider the periodization itself. How should one dissect this organization- dedicated-to-science? What moments is the historian to elevate to the status of 'turning points', so giving shape to the narrative but also inevitably imposing a particular rhythm and logic on it? There is no one answer to these questions, no one criterion for making one's cuts, no one way to transform a story into a history. The choice that we made - if one can call it a choice, for it was initially made only half-consciously - was to organize the history of CERN around the decisions to equip it with its major accelerators. Thus volume I took us up to 1954, when the organization was officially established with its 600 MeV synchro-cyclotron and its 28 GeV proton synchrotron ^ Volume II took us up to 1965 when it was decided that CERN should be equipped with a proton-proton collider, the Intersecting Storage Rings to be followed as soon as possible by a major fixed-target machine, formally adopted in fact only six years later (the 300 GeV Super Proton Syn­ chrotron)^. This volume covers the period up to the late 1970s, precisely so as to include the decision to build a proton-antiproton collider at the SPS and to avoid entering the debate surrounding the decision to build CERN's next major accelerator, a large electron- positron collider. Studies on a LEP machine began in 1976, and the first major design report for an accelerator of circumference 22 km which was cost-optimized on 70 GeV per beam was pubHshed in 1978. In that same year the European high-energy physics com­ munity formally adopted a LEP as its next big machine. The debates over its design, ultimate target energy and funding were complex and controversial, and would have drawn us into the 1980s, a period deemed too recent to permit a sober historical analysis when the work on this volume got under way about five years ago. This mode of periodization bears reflection, all the more so since our use of it has never been explicitly questioned by the high-energy physics community itself. Its significance is twofold. Firstly, the kind of physics one can do depends on the kind of machine that one has at one's disposal: its energy, its intensity, and its flexibility are crucial variables in the definition of a research programme. Secondly, machines are expressions of power and prestige: power to shape and to dominate the research frontier, power to compete effec­ tively at the world level, power to raise money from governments. At heart then the periodization adopted in these three volumes of CERN's history is one which reflects and reinforces the ambition of the European high-energy physics community, and the science administrators and governments who supported them so reliably, to have the equipment needed to place them among the world leaders in their field of research. If the dates that have structured our narrative are necessarily to be taken as 'turning points' it is in the sense that at that moment another step was taken up the spiral of ever-increasing energy, a decision was taken to build an even more powerful machine. It is this that our history celebrates and legitimates. This choice of timespans is not without interest, far from it, but as we have said it is not the only one possible. We could, for example, have delimited our research using Nobel prizes missed and won (the two neutrinos, the J/psi, the W and the Z...). Or the reigns of the laboratory's successive Directors General (the Weisskopf era, the Gregory era...). Or the national science policies and foreign policies of CERN's member states, most notably Britain, France and Germany (which would have forced us to situate the laboratory in the context of European economic, political and miUtary reconstruction)^. Each of these options imposes its own rhythm and chronology as well as its own set of pertinent questions. No one is all-encompassing, no one of them can give us a 'complete picture' of CERN's history. Indeed no such picture exists; it is rather up to the historian to fabricate a picture out of the materials available - documents, interviews, first hand experience. This picture will necessarily be framed by a variety of implicit and explicit assumptions and questions, assumptions and questions which are specific to the conjuncture in which the work is produced. The characteristics of the period which we have chosen to cover here, bounded as it is by decisions about accelerators, are not easily captured in a few lines. For volume I our task was simple: we described the launch of CERN, how and why a handful of European scientists and science administrators imposed a costly laboratory equipped with machines far bigger than anything ever constructed in Europe on a physics community and on governments which were often sceptical, not to say hostile to the feasibihty and indeed desirabihty of the project. Similarly, for volume II, we quickly settled on a catch-all phrase. The book described the building and the early running of the laboratory: the construction of the machines, the negotiations over the laboratory's internal structure and experiments committee system, the difficulties raised for scientists and governments alike in moving from a period of machine construction to one of exploitation, the sometimes bruising debates with the outside users community over access to the laboratory's facil­ ities, the first physics programmes, and the choice of CERN's next generation of accel­ erators. Now as we move into the next period, many of these earlier difficulties have been resolved. There were of course moments of great drama: the titanic struggle to have the SPS accepted by governments as CERN's major fixed-target machine for the 1970s, the visitors revolt in the early 1970s, the announcement of weak neutral currents and the disbehef and depression that 'the ISR [had] missed the J/psi and later missed the upsilon'"*, the testing and implementation of the beam-shrinking technique of stochastic cooling. But these moments of drama apart, CERN seems to have 'ticked along' quite smoothly in these years, its global budgets, its equipment, its experimental programmes, and its staff (as well as their experience in managing a major laboratory), expanding steadily. A little story will make the point. In volume II we made much of CERN's un- preparedness for doing physics at 28 GeV, as evidenced typically by its lack of suitable beam transport equipment, a criterion which encapsulated many features of the young CERN: inexperience on the experimental floor, in the directorate and in the Council, the Notes: p. 35 6 CERNfrom the mid-1960s to the late 1970s relations between physicists and engineers and about what it meant to do physics, the emergence of a number of mandarins each determined to control a part of the physics programme for himself. Indeed when the PS experimental programme got under way early in 1960, CERN had only three beam transport elements of its own. The first beams were made without lenses and with magnets begged or borrowed from various sources. Welding generators were put into service as power supplies and the ordinary town water was used for cooling. Something like a third of the South [experimental] Hall was still a workshop and the North Hall was still being used as an assembly area by the PS Division'. Ten years later there were about 250 beam transport elements at hand for the PS experimental programme, and floorspace had almost quadrupled from 2500m^ to 9000m^. The labo­ ratory staff had learnt what it meant to do physics around big machines^. John Adams, who had directed the construction of the PS, surely had the traumas of the early 1960s in mind when he wrote, in 1977, that 'One of the triumphs of the SPS Programme planning [for which he was partly responsible of course] [...] was that the accelerator and the massive detectors were ready at the same time so that experimental research could begin this year without delay'^. In short, in the period covered by this book, CERN had overcome many of its early difficulties and was functioning efficiently as a European organization-dedi- cated-to-science. Seen in this light, there seems to be another kind of logic linking our three volumes of CERN's history. It is the pervasive and pernicious logic of birth, adolescence and adult­ hood (what a happy coincidence that we have just three tomes!), each one following on the other and consolidating the 'lessons' learnt before. This spurious continuity, this super­ ficial metaphor must be resisted at all costs. For it masks the specificity of different periods in the laboratory's development, the displacements and ruptures which differentiate contexts and practices from one another over time. For example, the political and eco­ nomic world in which CERN hved in the late 1960s was totally different from that in the early 1950s when it was established.