| European Organization for Nuclear Research Organisation européenne pour la recherche nucléaire | |
|---|---|
 | |
 Member states | |
| Formation | 29 September 1954[1] |
| Headquarters | Geneva, Switzerland |
| Membership | 21 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), known as CERN or Cern (
/ˈsɜrn/; French pronunciation: [sɛʁn]; see History) is an international organization whose purpose is to operate the world's largest particle physicslaboratory, in the northwest suburbs of Geneva on the Franco–Swiss border (46°14′3″N 6°3′19″E). Established in 1954, the organization has 20 European member states.
/ˈsɜrn/; French pronunciation: [sɛʁn]; see History) is an international organization whose purpose is to operate the world's largest particle physicslaboratory, in the northwest suburbs of Geneva on the Franco–Swiss border (46°14′3″N 6°3′19″E). Established in 1954, the organization 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 and hosts some 10,000 visiting scientists and engineers, representing 608 universities and research facilities and 113 nationalities.
CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research. Numerous experiments have been constructed at CERN by international collaborations to make use of them. It is also the birthplace of the World Wide Web. The main site at Meyrin also has a large computer centre containing very powerful data-processing facilities primarily for experimental data analysis and, because of the need to make them available to researchers elsewhere, has historically been a major wide area networking hub.
History
The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe.a[›][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 its establishment the work at the laboratory went beyond the study of the atomic nucleus into higher-energy physics, which is mainly concerned 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.
[edit]Scientific achievements
Several important achievements in particle physics have been made during experiments at CERN. They include:
- 1973: The discovery of neutral currents in the Gargamelle bubble chamber.[3]
- 1983: The discovery of W and Z bosons in the UA1 and UA2 experiments.[4]
- 1989: The determination of the number of light neutrino families at the Large Electron–Positron Collider(LEP) operating on the Z boson peak.
- 1995: The first creation of antihydrogen atoms in the PS210 experiment.[5]
- 1999: The discovery of direct CP violation in the NA48 experiment.[6]
- 2010: The isolation of 38 atoms of antihydrogen[7]
- 2011: Maintaining antihydrogen for over 15 minutes[8]
- 2012: A boson with mass around 125 GeV consistent with long-sought Higgs boson.[9]
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."
[edit]Computer science
See also: History of the World Wide Web
The World Wide Web began as a CERN project called ENQUIRE, initiated by Tim Berners-Lee in 1989 andRobert 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, among others, theEnabling Grids for E-sciencE (EGEE) and LHC Computing Grid projects. It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland.
[edit]Faster-than-light neutrino anomaly
Main article: Faster-than-light neutrino anomaly
On September 22, 2011, the OPERA Collaboration reported 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]
[edit]Particle accelerators
[edit]Current complex
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:
- Two linear accelerators generate low energy particles. Linac2 accelerates protons to 50 MeV for injection into the Proton Synchrotron Booster (PSB), and Linac3 provides heavy ions at 4.2 MeV/u for injection into the Low Energy Ion Ring (LEIR).[16]
- The Proton Synchrotron Booster increases the energy of particles generated by the proton linear accelerator before they are transferred to the other accelerators.
- The Low Energy Ion Ring (LEIR) accelerates the ions from the ion linear accelerator, before transferring them to the Proton Synchrotron(PS). This accelerator was commissioned in 2005, after having been reconfigured from the previous Low Energy Antiproton Ring(LEAR).
- The 28 GeV Proton Synchrotron (PS), built in 1959 and still operating as a feeder to the more powerful SPS.
- The Super Proton Synchrotron (SPS), a circular accelerator with a diameter of 2 kilometres built in a tunnel, which started operation in 1976. It was designed to deliver an energy of 300 GeV and was gradually upgraded to 450 GeV. As well as having its own beamlines for fixed-target experiments (currently COMPASS and NA62), it has been operated as a proton–antiproton collider (the SppS collider), and for accelerating high energy electrons and positrons which were injected into the Large Electron–Positron Collider (LEP). Since 2008, it has been used to inject protons and heavy ions into the Large Hadron Collider (LHC).
- The On-Line Isotope Mass Separator (ISOLDE), which is used to study unstable nuclei. The radioactive ions are produced by the impact of protons at an energy of 1.0–1.4 GeV from the Proton Synchrotron Booster. It was first commissioned in 1967 and was rebuilt with major upgrades in 1974 and 1992.
- REX-ISOLDE increases the charge states of ions coming from the ISOLDE targets, and accelerates them to a maximum energy of 3 MeV/u.
- The Antiproton Decelerator (AD), which reduces the velocity of antiprotons to about 10% of the speed of light for research into antimatter.
- The Compact Linear Collider Test Facility, which studies feasibility issues for the future normal conducting linear collider project.
[edit]The Large Hadron Collider
Main article: Large Hadron Collider
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]
[edit]Decommissioned accelerators
- The original linear accelerator (LINAC 1).
- The 600 MeV Synchrocyclotron (SC) which started operation in 1957 and was shut down in 1991.
- The Intersecting Storage Rings (ISR), an early collider built from 1966 to 1971 and operated until 1984.
- The Large Electron–Positron Collider (LEP), which operated from 1989 to 2000 and was the largest machine of its kind, housed in a 27 km-long circular tunnel which now houses the Large Hadron Collider.
- The Low Energy Antiproton Ring (LEAR), commissioned in 1982, which assembled the first pieces of true antimatter, in 1995, consisting of nine atoms of antihydrogen. It was closed in 1996, and superseded by the Antiproton Decelerator.
[edit]Sites
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:
- A, in Switzerland, for all CERN personnel at specific times.
- B, in Switzerland, for all CERN personnel at all times. Often referred to as the main entrance.
- C, in Switzerland, for all CERN personnel at specific times.
- D, in Switzerland, for goods reception at specific times.
- E, in France, for French-resident CERN personnel at specific times. Controlled by customs personnel. Named "Porte Charles de Gaulle" in recognition of his role in the creation of CERN.[21]
- Tunnel entrance, in France, for equipment transfer to and from CERN sites in France by personnel with a specific permit. This is the only permitted route for such transfers. Under the CERN treaty, no taxes are payable when such transfers are made. Controlled by customs personnel.
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.
[edit]Financing (Budget 2010)
| Member state | Contribution | Mil. CHF | Mil. EUR |
|---|---|---|---|
 Germany | 20.30 % | 225.8 | 174.0 |
 France | 15.63 % | 173.8 | 134.0 |
 United Kingdom | 14.64 % | 162.8 | 125.0 |
 Italy | 11.64 % | 129.4 | 99.5 |
 Spain | 8.89 % | 98.9 | 76.1 |
 Netherlands | 4.55 % | 50.6 | 38.9 |
 Belgium | 2.82 % | 31.3 | 24.1 |
 Norway | 2.76 % | 30.7 | 23.6 |
 Poland | 2.66 % | 29.6 | 22.8 |
 Switzerland | 2.41 % | 26.9 | 20.7 |
 Sweden | 2.40 % | 26.7 | 20.5 |
 Austria | 2.25 % | 25.0 | 19.2 |
 Greece | 1.93 % | 21.5 | 16.5 |
 Denmark | 1.76 % | 19.6 | 15.1 |
 Finland | 1.49 % | 16.5 | 12.7 |
 Portugal | 1.18 % | 13.1 | 10.1 |
 Czech Republic | 1.08 % | 12.1 | 9.3 |
 Hungary | 0.69 % | 7.6 | 5.8 |
 Slovakia | 0.60 % | 6.7 | 5.2 |
 Bulgaria | 0.32 % | 3.6 | 2.7 |
| Total | 100 % | 1112.2 | 855.5 |
Exchange rates: 1 CHF = 0,88 EUR (beginning 2012)
[edit]Member states
 | This section may require cleanup to meet Wikipedia's quality standards. The specific problem is: The list of countries is disorganised, unclear and fragmented. So is the prose.. (July 2012) |
The original 12 CERN signatories in 1954 were:
Switzerland
Yugoslavia (later withdrawn).
All founding members remain in the CERN organisation, except Yugoslavia which left in 1961.
Since its foundation, CERN regularly accepted new members. All new members have remained in the organisation continuously since their acceptance, except Spain which joined in 1961, withdrew eight years later, and rejoined in 1983. CERN's membership history is as follows:
Of the twenty members, 18 are European Union member states.
Romania became a candidate for accession to CERN in 2010 and will become a member in 2015.[22]
Serbia became a candidate for accession to CERN on December 19, 2011, associate member on January 10, 2012.[23]
Israel became an associate member in 2011, with a decision to be made on its full membership in 2013.[24]
Four countries applying for membership have all formally confirmed their wish to become members.[25]
Cyprus since 14 February 2006, Non-Member State status
Slovenia since 7 January 1991, Non-Member State status
Turkey since 1961, Observer State status
Five countries have observer status:[26]
Russia – since 1993
Japan – since 1995
United States – since 1997
India – since 2002
Also observers are the following international organizations:
UNESCO – since 1954
European Commission – since 1985
Non-Member States (with dates of Co-operation Agreements) currently involved in CERN programmes are:
Algeria
Argentina – 11 March 1992
Armenia – 25 March 1994
Australia – 1 November 1991
Azerbaijan – 3 December 1997
Belarus – 28 June 1994
Brazil – 19 February 1990 & October 2006
Canada – 11 October 1996
Chile – 10 October 1991
China – 12 July 1991, 14 August 1997 & 17 February 2004
Colombia – 15 May 1993
Croatia – 18 July 1991
Cuba
Egypt – 16 January 2006
Estonia – 23 April 1996
Georgia – 11 October 1996
Iceland – 11 September 1996
Iran – 5 July 2001
Ireland
Jordan - 12 June 2003.[27] MoU with Jordan and SESAME, in preparation of a cooperation agreement signed in 2004.[28]
Lithuania – 9 November 2004
Macedonia – 27 April 2009[29]
Mexico – 20 February 1998
Montenegro – 12 October 1990
Morocco – 14 April 1997
New Zealand – 4 December 2003
Pakistan – 1 November 1994.
Peru – 23 February 1993
Saudi Arabia – 21 January 2006
South Africa – 4 July 1992
South Korea – 25 October 2006.
Republic of China (Taiwan)
Thailand
United Arab Emirates – 18 January 2006
Ukraine – 2 April 1993
Vietnam
| [show]Maps of the history of CERN membership |
|---|
[edit]Public exhibits
Facilities at CERN open to the public include:
- The Globe of Science and Innovation, which opened in late 2005 and is used four times a week for special exhibits.
- The Microcosm museum on particle physics and CERN history.
- The Hindu deity, Shiva engaging in the Nataraja dance, parallelling the movements or “dance” of subatomic particles.[30]
[edit]In popular culture
- CERN's Large Hadron Collider is the subject of a (scientifically accurate) rap video starring Katherine McAlpine with some of the facility's staff.[31][32]
- CERN is depicted in an episode of South Park (Season 13, Episode 6) called "Pinewood Derby". Randy Marsh, the father of one of the main characters, breaks into the "Hadron Particle Super Collider in Switzerland" and steals a "superconducting bending magnet created for use in tests with particle acceleration" to use in his son Stan's Pinewood Derby racer. Randy breaks into CERN dressed in disguise as Princess Leia from the Star Wars saga. The break-in is captured on surveillance tape which is then broadcast on the news.[33]
- John Titor, an online bulletin board poster claiming to be a time traveler, referenced CERN in his predictions, claiming it would create miniature black holes and discover time travel.[citation needed]
- CERN is depicted in the visual novel (later adapted into an anime series) Steins;Gate under the name SERN. In the video game and anime series, SERN is a shadowy organization that has been researching time travel and attempts to use it to restructure and control the world in the dystopian near future. The game references the John Titor legend mentioned above.
- In Dan Brown's mystery-thriller novel Angels & Demons, a canister of antimatter is stolen from CERN.[34]
- In the popular children's series The 39 Clues, CERN is said to be an Ekaterina stronghold hiding the clue hydrogen.
- In Robert J. Sawyer's science fiction novel Flashforward (novel), at CERN, the Large Hadron Collider accelerator is performing a run to search for the Higgs boson when the entire human race sees themselves twenty-one years and six months in the future.
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