Too often trip reports are just boring administrative documents, but this one caused a radical rethink of the design for CERN’s Proton Synchrotron. Suddenly a relatively straightforward engineering challenge became a development project for an untested idea.

Plans were already underway for CERN’s large accelerator, a scaled-up version of Brookhaven’s Cosmotron, when Odd Dahl, Frank Goward and Rolf Wideröe visited Brookhaven in 1952. There they joined in discussions about a new strong-focusing (or alternating gradient focusing) technique, which meant smaller magnets could be used to guide particles round an accelerator provided they were arranged with their field gradients facing alternately inwards and outwards instead of the conventional outward-facing alignment. Dahl recommended laying aside plans for a 10 GeV accelerator for the time being in order to investigate the idea further (CERN-PS-S4).

It was a risky decision to follow this unexplored route, but one that paid off by allowing construction of a much more powerful machine at little extra cost. When the Proton Synchrotron came into operation in November 1959 it had an energy of 24 GeV, later increased to 28 GeV.

Safety is top priority in any scientific research laboratory, and fire prevention was an important issue from the earliest days of CERN. The newly constructed buildings were fitted with smoke detectors, and voluntary fire brigades and first aid teams were set up among staff members.  

The appointment of CERN’s first fire service chief, Pierre Vosdey, in July 1956 marked the start of the professional firefighting service that CERN enjoys today. Experienced firemen were recruited, who trained more volunteers. The service expanded during 1957, providing 24-hour cover and acquiring a fire engine, an ambulance, a 14 metre ladder, a motor pump, smoke detectors and 250 fire extinguishers. This photo shows some of the team in 1959. Today the CERN fire brigade has around 50 members and continues to work closely with the Swiss and French fire services to ensure safety on-site.

On 14 June 1956 a telegram from Frederick Reines and Clyde Cowan informed Wolfgang Pauli that neutrinos had been detected from fission fragments - nearly 26 years after Pauli first postulated the neutral particle as a solution to the missing energy during beta decay.

Pauli had outlined his theory in a letter to the ‘Dear radioactive ladies and gentlemen’ at the Tübingen conference in December 1930, excusing his own absence from the conference on the grounds that he had to go to a dance in Zürich. The name “neutrino” was coined by Enrico Fermi in 1933.  

Apparently Pauli’s reply to the telegram did not arrive, so it survives only in the form of the draft sent by a secretary - Pauli simply says “Thanks for message. Everything comes to him who knows how to wait.”

A historic moment passed almost unnoticed on 17 May 1954, as the first excavation work started in the Meyrin countryside and construction of CERN began. Future events of this kind were celebrated with speeches, press coverage and parties, but this was a quiet and purely unofficial ceremony.

Geneva had been chosen as the site for the proposed laboratory in October 1952 and approved by a referendum in the canton of Geneva in June 1953, but CERN’s status was provisional until completion of the ratification process at the end of September 1954. Nonetheless, CERN staff were already hard at work, and those based locally (at the Institut de Physique and Villa Cointrin) assembled in Meyrin along with representatives of the Genevan authorities and the chairman of the provisional CERN Council, Robert Valeur, to watch work begin on their new home.   

Among the scientific documents in CERN’s Wolfgang Pauli Archive is a rather unusual item – a copy of the script parodying Goethe’s Faust performed at the Niels Bohr Institute conference, 3-13 April 1932 (exact date of performance not known). Written mostly by Max Delbrück, and decorated with caricatures of the protagonists, the skit features Pauli (Mephistopheles) trying to sell the idea of the neutrino (Gretchen) to a sceptical Paul Ehrenfest (Faust)!

Pauli had postulated the existence of this weightless particle in his famous letter to the ‘Dear radioactive ladies and gentlemen’ at the Tübingen conference in December 1930, but he had to wait until 1956 for experimental confirmation by Reines and Cowan, so in 1932 it was still the subject of debate. Pauli’s reputation for sharp wit made him ideal for his satanic rôle, but in his absence the part was played by Léon Rosenfeld. The rôle of God was assigned to Bohr. The script (in German), can be seen here. An English translation is given in George Gamow’s Thirty Years that Shook Physics.

Tim Berners-Lee made a first proposal for information management at CERN in March 1989 (no exact date is given). A later version was written in 1990, but this early document is particularly interesting because it includes annotations by his boss, Mike Sendall, whose general comment was ‘Vague but exciting…’! The project eventually grew to become the World Wide Web.  

In this document Berners-Lee outlined the problems of losing information at CERN, the advantages of linked information and hypertext and the practical requirements of his idea. He proposed ‘a universal linked information system, in which generality and portability are more important than fancy graphics techniques and complex extra facilities. The aim of the project would be to allow a place to be found for putting any information or reference which one felt was important, and a way of finding it afterwards.’ With the help of Robert Cailliau and others he was able to make the dream a reality.

“We have just signed the Agreement which constitutes the official birth of the project you fathered at Florence. Mother and child are doing well, and the doctors send you their greetings.” This was the message sent to Isidor Rabi on 15 Feb 1952 by the signatories of an agreement establishing the provisional European Council for Nuclear Research.

Scientists and politicians had been pressing for the creation of a European laboratory to pool resources depleted after World War Two, and Nobel laureate Rabi added his support at the fifth UNESCO General Conference (Florence, June 1950), where he tabled a resolution to “assist and encourage the formation of regional research centres and laboratories in order to increase and make more fruitful the international collaboration of scientists…” 

The first resolution concerning the establishment of a European Council for Nuclear Research was adopted at an intergovernmental meeting of UNESCO in Paris in December 1951. The provisional Council, set up in 1952, was dissolved when the European Organization for Nuclear Research officially came into being in 1954, though the acronym CERN (Conseil Européen pour la Recherche Nucléaire) was retained.

The scene is the control room of the Intersecting Storage Rings (ISR) on 27 January 1971. Kjell Johnsen, leader of the ISR construction team, has just announced successful recording of the first ever interactions from colliding proton beams. It was a triumphant moment, not least because the ISR had been an ambitious and highly controversial project, with several years of heated debate preceding its final unanimous approval by the CERN council in June 1965.

The interconnected rings, 300 metres in diameter and fed from the Proton Synchrotron (PS), ran from March 1971 until December 1983. At the official inauguration on 16 October 1871, Werner Heisenberg handed the President of the CERN council, Edoardo Amaldi, a golden key that controlled the transfer of protons from the PS to the ISR, symbolizing their hopes that the new machine would be the key to a thorough understanding of the world of elementary particle physics. He said such a symbolic key should first be in the hands of the experimentalists.  At the closure ceremony on 26 June 1984, the key was formally handed back to the theorists, in the person of Viktor Weisskopf.

A team photo celebrates the completion of the SPS tunnel in July 1974. The Super Proton Synchrotron (SPS) was the first of CERN’s giant accelerators. It was also the first cross-border accelerator. Excavation took around two years, and on 31 July 1974 the Robbins tunnel-boring machine returned to its starting point having crossed the Franco-Swiss border and excavated a tunnel with a circumference of 7 kilometres and an average depth of 40 metres below the surface.

The SPS was commissioned in 1976, and a highlight of its  career came in 1983 with the announcement of the Nobel prize-winning discovery of W and Z particles.

A log book entry written by Wolfgang Gentner, the head of SC Division, and signed by various colleagues, tells us that a short celebration was held on the 1st of August 1957 following the successful  appearance of the first circulating beam.

The 600 MeV Synchrocyclotron (SC)  was CERN’s first accelerator and provided beams for its earliest particle and nuclear physics experiments.  It was a remarkably long-lived machine, even when superseded by the larger Proton Synchrotron, and operated for 33 years before being decommissioned in December 1990. Work is currently underway to give the SC a new lease of life as an exhibition area and visitor attraction.