30 September 2014
CERN at 60: Biggest moments at flagship physics lab

CERN, Europe’s particle-physics laboratory and the place famous most recently for the discovery of the Higgs boson, is celebrating its sixtieth birthday today.

The name CERN originally was the French acronym for Conseil Européen pour la Recherche Nucléaire, or European Council for Nuclear Research, and its convention officially came into force on 29 September 1954. In the wake of a war that had torn the continent apart, a small group of scientists and policy-makers created CERN in an attempt to use fundamental research to reunite Europe.

From 12 founding members, the organization has today grown to 21 states, with scientists at the lab hailing from almost 100 countries around the globe.

While CERN hosts a celebration at its home near Geneva, Switzerland, Nature looks back at some of the lab’s most significant moments from the past six decades. The links below are to a mixture of free and paywall pages, and will no doubt miss out many big CERN moments. Please add your own to the comments section below.

1954: CERN is set up. Nature outlines plans for the organization in an essay published in October of the previous year. CERN’s ‘official birth’ had come in 1952, with an agreement establishing the provisional council.

1968: Georges Charpak invents the multiwire proportional chamber. Until this time, particle physics had looked for traces of particle collisions by photographing their wake in bubble chambers or spark chambers. Charpak’s invention — a gas-filled box in which amplifiers boosted the signals detected by each wire — allowed for a 1,000-fold increase in detection rate. To this day, most high-energy physics experiments still use detectors based on this principle. Charpak’s Nature obituary in 2010 celebrated his life and achievements.

1978: CERN stores antiprotons for the first time. Paul Dirac had predicted the existence of antimatter in 1928, and antiprotons were discovered in 1932. In 1978, CERN succeeds in circulating several hundred antiprotons for 85 hours in a machine called the Initial Cooling Experiment, in a study aimed at exploring the feasibility of colliding beams of high-energy protons and antiprotons. Today CERN’s antiproton decelerator delivers low-energy antiprotons  for studies a range of experiments studying the properties of antimatter.

1983: CERN’s 6.9-kilometre-long Super Proton Synchrotron (SPS) discovers the particle carriers of the weak force, the W and Z bosons. In this Nature News and Views from April 1983, Frank Close, a particle physicist now at the University of Oxford, UK, discusses the first signs of the W boson at the SPS’s UA1 experiment, and hints that the Z will be next.

1984: According to a Nature News & Views (penned by John Maddox, then Nature‘s editor-in-chief), CERN discovers the top quark, the last missing element in the family of six known quarks that includes the ‘up’ and ‘down’ quarks that make up protons and neutrons. That announcement, however, will turn out to be premature, and the credit for the discovery of the top quark now goes universally to CERN’s biggest US competitor, the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. It found the top quark in 1995.

1989: CERN computer scientist Tim Berners-Lee’s drafts a paper outlining plans for an information-management system, which at the time he termed “the mesh” but which later becomes known as the World Wide Web. Berners-Lee’s boss, Mike Sendall, famously replies that the proposal was “vague, but exciting”, giving Berners-Lee the green light for development. The world’s first web page address is born the following year (this copy is from 1992).

2000: The 27-kilometre Large Electron-Positron (LEP) collider at CERN closes after 11 years of operation to make way for the Large Hadron Collider (LHC), to be built in the same tunnels. LEP experiments have confirmed the Standard Model, the theory that describes fundamental particles and forces, to an extraordinary degree of precision. Nature reporter Alex Hellmans reports on the melancholy, and hope, in the wake of the shutdown.

2012: On 4 July scientists at the LHC’s ATLAS and CMS experiments announce that they have found a clear signal of the Higgs boson, and reporter Geoff Brumfiel records the moment in a live blog (and later in an article). The announcement, made by the ATLAS and CMS experiments, causes waves around the world, and in 2013 earns theoretical physicists François Englert and Peter Higgs the Nobel Prize in Physics for their prediction of the mechanism.

Source of information: Nature
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