Coordinates: 46°14′03″N 6°03′10″E / 46.23417°N 6.05278°E
| European Organization for Nuclear Research Organisation européenne pour la recherche nucléaire |
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Member states |
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| Formation | 29 September 1954[1] |
| Headquarters | Geneva, Switzerland |
| Membership | 20 member states and 7 observers |
| Director General | Rolf-Dieter Heuer |
| Website | cern.ch |
The European Organization for Nuclear Research (French: Organisation européenne pour la recherche nucléaire Italian: Organizzazione Europea per la Ricerca Nucleare ), known as CERN or Cern (pron.: /ˈsɜrn/; French pronunciation: [sɛʁn]; see History) is an international organization whose purpose is to operate the world's largest particle physics laboratory. Established in 1954, the organization is based in the northwest suburbs of Geneva on the Franco–Swiss border, (46°14′3″N 6°3′19″E / 46.23417°N 6.05528°E) and has 20 European member states.
The term CERN is also used to refer to the laboratory, which employs just under 2,400 full-time employees, 1,500 part-time employees, and hosts some 10,000 visiting scientists and engineers, representing 608 universities and research facilities and 113 nationalities.[citation needed]
CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research - as a result, numerous experiments have been constructed at CERN following international collaborations. It is also the birthplace of the World Wide Web. The main site at Meyrin has a large computer centre containing powerful data-processing facilities, primarily for experimental-data analysis; because of the need to make these facilities available to researchers elsewhere, it has historically been a major wide area networking hub.
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The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe.[1] The acronym CERN originally stood in French for Conseil Européen pour la Recherche Nucléaire (European Council for Nuclear Research), which was a provisional council for setting up the laboratory, established by 12 European governments in 1952. The acronym was retained for the new laboratory after the provisional council was dissolved, even though the name changed to the current Organisation Européenne pour la Recherche Nucléaire (European Organization for Nuclear Research) in 1954.[2] According to Lew Kowarski, a former director of CERN, when the name was changed, the acronym could have become the awkward OERN, and Heisenberg said that the acronym could "still be CERN even if the name is [not]".[citation needed]
Soon after the laboratory's establishment, its work went beyond the study of the atomic nucleus into higher-energy physics, which is concerned mainly with the study of interactions between particles. Therefore the laboratory operated by CERN is commonly referred to as the European laboratory for particle physics (Laboratoire européen pour la physique des particules) which better describes the research being performed at CERN.
Several important achievements in particle physics have been made during experiments at CERN. They include:
The 1984 Nobel Prize in physics was awarded to Carlo Rubbia and Simon van der Meer for the developments that led to the discoveries of the W and Z bosons. The 1992 Nobel Prize in physics was awarded to CERN staff researcher Georges Charpak "for his invention and development of particle detectors, in particular the multiwire proportional chamber."
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This NeXT Computer used by British scientist Sir Tim Berners-Lee at CERN became the first Web server.
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This Cisco Systems router at CERN was probably one of the first IP routers deployed in Europe.[citation needed]
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The World Wide Web began as a CERN project called ENQUIRE, initiated by Tim Berners-Lee in 1989 and Robert Cailliau in 1990.[10] Berners-Lee and Cailliau were jointly honoured by the Association for Computing Machinery in 1995 for their contributions to the development of the World Wide Web.
Based on the concept of hypertext, the project was aimed at facilitating sharing information among researchers. The first website went on-line in 1991. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone. A copy[11] of the original first webpage, created by Berners-Lee, is still published on the World Wide Web Consortium's website as a historical document.
Prior to the Web's development, CERN had been a pioneer in the introduction of Internet technology, beginning in the early 1980s. A short history of this period can be found at CERN.ch.[12]
More recently, CERN has become a centre for the development of grid computing, hosting projects including the Enabling Grids for E-sciencE (EGEE) and LHC Computing Grid. It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland.
On 22 September 2011, the OPERA Collaboration reported the detection of 17-GeV and 28-GeV muon neutrinos, sent 730 kilometers (454 miles) from CERN near Geneva, Switzerland to the Gran Sasso National Laboratory in Italy, traveling apparently faster than light by a factor of 2.48×10−5 (approximately 1 in 40,000), a statistic with 6.0-sigma significance.[13] However, in March 2012 it was reported by a new team of scientists for CERN, Icarus, that the previous experiment was most likely flawed and will be retested by scientists of both the Opera and Icarus teams;[14] on 16 March, CERN came up with press release, saying the results were flawed due to incorrectly connected GPS-synchronization cable.[15]
CERN operates a network of six accelerators and a decelerator. Each machine in the chain increases the energy of particle beams before delivering them to experiments or to the next more powerful accelerator. Currently active machines are:
Most of the activities at CERN are currently directed towards operating the new Large Hadron Collider (LHC), and the experiments for it. The LHC represents a large-scale, worldwide scientific cooperation project.
The LHC tunnel is located 100 metres underground, in the region between the Geneva International Airport and the nearby Jura mountains. It uses the 27 km circumference circular tunnel previously occupied by LEP which was closed down in November 2000. CERN's existing PS/SPS accelerator complexes will be used to pre-accelerate protons which will then be injected into the LHC.
Seven experiments (CMS, ATLAS, LHCb, MoEDAL[17] TOTEM, LHC-forward and ALICE) will run on the collider; each of them will study particle collisions from a different point of view, and with different technologies. Construction for these experiments required an extraordinary engineering effort. Just as an example, a special crane had to be rented from Belgium in order to lower pieces of the CMS detector into its underground cavern, since each piece weighed nearly 2,000 tons. The first of the approximately 5,000 magnets necessary for construction was lowered down a special shaft at 13:00 GMT on 7 March 2005.
This accelerator has begun to generate vast quantities of data, which CERN streams to laboratories around the world for distributed processing (making use of a specialised grid infrastructure, the LHC Computing Grid). In April 2005, a trial successfully streamed 600 MB/s to seven different sites across the world. If all the data generated by the LHC is to be analysed, then scientists must achieve 1,800 MB/s before 2008.
The initial particle beams were injected into the LHC August 2008.[18] The first attempt to circulate a beam through the entire LHC was at 8:28 GMT on 10 September 2008,[19] but the system failed because of a faulty magnet connection, and it was stopped for repairs on 19 September 2008.
The LHC resumed operation on Friday 20 November 2009 by successfully circulating two beams, each with an energy of 3.5 trillion electron volts. The challenge that the engineers then faced was to try to line up the two beams so that they smashed into each other. This is like "firing two needles across the Atlantic and getting them to hit each other" according to the LHC's main engineer Steve Myers, director for accelerators and technology at the Swiss laboratory.
At 1200 BST on Tuesday 30 March 2010 the LHC successfully smashed two proton particle beams travelling with 3.5 TeV (trillion electron volts) of energy, resulting in a 7 TeV event. However, this is just the start of the road toward the expected discovery of the Higgs boson. This is mainly because the amount of data produced is so huge it could take up to 24 months to completely analyse it. When the 7 TeV experimental period ended, the LHC revved up to 8 TeV (4 TeV acceleration in both directions) in March 2012, and will begin particle collisions at that rate in early April 2012. At the end of 2012 the LHC will be shut down for maintenance for up to two years, to strengthen the huge magnets inside the accelerator. It will then attempt to create 14 TeV events. In July 2012, CERN scientists claimed to have discovered a new sub-atomic particle that could be the much sought after Higgs boson believed to be essential for formation of the Universe.[20]
The smaller accelerators are on the main Meyrin site (also known as the West Area), which was originally built in Switzerland alongside the French border, but has been extended to span the border since 1965. The French side is under Swiss jurisdiction and there is no obvious border within the site, apart from a line of marker stones. There are six entrances to the Meyrin site:[citation needed]
The SPS and LEP/LHC tunnels are almost entirely outside the main site, and are mostly buried under French farmland and invisible from the surface. However they have surface sites at various points around them, either as the location of buildings associated with experiments or other facilities needed to operate the colliders such as cryogenic plants and access shafts. The experiments are located at the same underground level as the tunnels at these sites.
Three of these experimental sites are in France, with ATLAS in Switzerland, although some of the ancillary cryogenic and access sites are in Switzerland. The largest of the experimental sites is the Prévessin site, also known as the North Area, which is the target station for non-collider experiments on the SPS accelerator. Other sites are the ones which were used for the UA1, UA2 and the LEP experiments (the latter which will be used for LHC experiments).
Outside of the LEP and LHC experiments, most are officially named and numbered after the site where they were located. For example, NA32 was an experiment looking at the production of charmed particles and located at the Prévessin (North Area) site while WA22 used the Big European Bubble Chamber (BEBC) at the Meyrin (West Area) site to examine neutrino interactions. The UA1 and UA2 experiments were considered to be in the Underground Area, i.e. situated underground at sites on the SPS accelerator.
Most of the roads on the CERN campus are named after famous phycisists, e.g.- Richard Feynman, Niels Bohr, Albert Einstein.
Since its foundation by 12 members in 1954, CERN regularly accepted new members. All new members have remained in the organisation continuously since their accession, except Spain and Yugoslavia. Spain first joined CERN in 1961, withdrew in 1969, and rejoined in 1983. Yugoslavia was a founding member of CERN but left in 1961. Initially only West Germany was a (founding) member of CERN. Of the twenty members, 18 are European Union member states. Switzerland and Norway are not.
| Member state | Status since | Contr. (mill.CHF for 2012) |
Contr. (% for 2012) |
|---|---|---|---|
| 29 September 1954 | 30.83 | 2.62% | |
| 29 September 1954 | 19.86 | 1.69% | |
| 29 September 1954 | 169.82 | 14.46% | |
| 29 September 1954 | 219.10 | 18.65% | |
| 29 September 1954 | 17.75 | 1.51% | |
| 29 September 1954 | 120.62 | 10.27% | |
| 29 September 1954 | 49.71 | 4.23% | |
| 29 September 1954 | 26.85 | 2.29% | |
| 29 September 1954 | 29.81 | 2.54% | |
| 29 September 1954 | 55.70 | 4.74% | |
| 29 September 1954 | 146.96 | 12.51% | |
| 1 June 1959 | 23.70 | 2.02% | |
| 11 March 1999 | 3.08 | 0.26% | |
| 1 July 1993 | 10.60 | 0.90% | |
| 1 January 1991 | 15.01 | 1.28% | |
| 1 July 1992 | 6.85 | 0.58% | |
| 1 January 1986 | 14.49 | 1.23% | |
| 1 July 1991 | 31.36 | 2.67% | |
| 1 July 1993 | 5.20 | 0.44% | |
| 1 January 1983 | 87.73 | 7.47% | |
| Candidate, Associate Members | |||
| 2008 | 5.02 | 0.43% | |
| 2011 | 3.63 | 0.31% | |
| 2012 | % | ||
| 2012[25] | % | ||
| Total Members, Candidates and Associates | 1,092.68[26] | 93.01% | |
| 1 July 1985[28] | 17.3 | 1.47% | |
| Other income | — | 64.8 | 5.52% |
| Total CERN | 1,174.78[27] | 100.0% |
| Maps of the history of CERN membership |
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Associate Members, Candidates (note that dates are initial signature, not of ratification):
Four countries applying for membership have all formally confirmed their wish to become members.[33]
Five countries have observer status:[34]
Also observers are the following international organizations:
Non-Member States (with dates of Co-operation Agreements) currently involved in CERN programmes are:
Facilities at CERN open to the public include:
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