The European Organization for Nuclear Research, known as CERN (; ; ), is an

intergovernmental organization Globalization Globalization, or globalisation (English in the Commonwealth of Nations, Commonwealth English; American and British English spelling differences#-ise, -ize (-isation, -ization), see spelling differences), is the process of ...

that operates the largest

particle physics Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) an ...

laboratory in the world. Established in 1954, it is based in a northwestern suburb of

Geneva , neighboring_municipalities= Carouge, Chêne-Bougeries, Cologny, Lancy, Grand-Saconnex, Pregny-Chambésy, Vernier, Veyrier , website = https://www.geneve.ch/ Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevr ...

, on the France–Switzerland border. It comprises 23 member states, and

Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...

(admitted in 2013) is currently the only non-European country holding full membership. CERN is an official

United Nations General Assembly observer The United Nations General Assembly has granted observer status to international organizations, entities, and non-member states, to enable them to participate in the work of the United Nations General Assembly, though with limitations. The Genera ...

. The acronym CERN is also used to refer to the laboratory; in 2019, it had 2,660 scientific, technical, and administrative staff members, and hosted about 12,400 users from institutions in more than 70 countries. In 2016, CERN generated 49

petabytes The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable uni ...

of data. CERN's main function is to provide the

particle accelerator A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies, and to contain them in well-defined beams. Large accelerators are used for fundamental research in particle ...

s and other infrastructure needed for high-energy physics research — consequently, numerous experiments have been constructed at CERN through international collaborations. CERN is the site of the Large Hadron Collider (LHC), the world's largest and highest-energy particle collider. The main site at

Meyrin Meyrin () is a municipality of the Canton of Geneva, Switzerland. The main site of CERN, the European particle physics research organisation, is in Meyrin. Meyrin was originally a small agricultural village until the 1950s, when construction of ...

hosts a large computing facility, which is primarily used to store and analyze data from experiments, as well as simulate

events Event may refer to: Gatherings of people * Ceremony, an event of ritual significance, performed on a special occasion * Convention (meeting), a gathering of individuals engaged in some common interest * Event management, the organization of ev ...

. As researchers require remote access to these facilities, the lab has historically been a major

wide area network A wide area network (WAN) is a telecommunications network that extends over a large geographic area. Wide area networks are often established with leased telecommunication circuits. Businesses, as well as schools and government entities, u ...

hub. CERN is also the birthplace of the

World Wide Web The World Wide Web (WWW), commonly known as the Web, is an information system enabling documents and other web resources to be accessed over the Internet. Documents and downloadable media are made available to the network through web ...

History

The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe. The acronym CERN originally represented the French words for ('European Council for Nuclear Research'), which was a provisional council for building the laboratory, established by 12 European governments in 1952. During these early years, the council worked at the

University of Copenhagen The University of Copenhagen ( da, Københavns Universitet, KU) is a prestigious public research university in Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in Scandinavia after Uppsala Unive ...

under the direction of

Niels Bohr Niels Henrik David Bohr (; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922 ...

before moving to its present site in Geneva. The acronym was retained for the new laboratory after the provisional council was dissolved, even though the name changed to the current ('European Organization for Nuclear Research') in 1954. According to

Lew Kowarski Lew Kowarski (10 February 1907, Saint Petersburg – 30 July 1979, Geneva) was a naturalized French physicist. He was a lesser-known but important contributor to nuclear science. Early life Lew Kowarski was born in Saint Petersburg to Nicholas K ...

, a former director of CERN, when the name was changed, the abbreviation could have become the awkward OERN, and

Werner Heisenberg Werner Karl Heisenberg () (5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the main pioneers of the theory of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent serie ...

said that this could "still be CERN even if the name is ot. CERN's first president was Sir Benjamin Lockspeiser.

Edoardo Amaldi Edoardo Amaldi (5 September 1908 – 5 December 1989) was an Italian physicist. He coined the term "neutrino" in conversations with Enrico Fermi distinguishing it from the heavier "neutron". He has been described as "one of the leading nuclear ...

was the general secretary of CERN at its early stages when operations were still provisional, while the first Director-General (1954) was

Felix Bloch Felix Bloch (23 October 1905 – 10 September 1983) was a Swiss-American physicist and Nobel physics laureate who worked mainly in the U.S. He and Edward Mills Purcell were awarded the 1952 Nobel Prize for Physics for "their development of new ...

. The laboratory was originally devoted to the study of

atomic nuclei The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment. After the discovery of the neutron ...

, but was soon applied to higher-energy physics, concerned mainly with the study of interactions between subatomic particles. Therefore, the laboratory operated by CERN is commonly referred to as the European laboratory for particle physics (), which better describes the research being performed there.

Founding members

At the sixth session of the CERN Council, which took place in Paris from 29 June – 1 July 1953, the convention establishing the organization was signed, subject to ratification, by 12 states. The convention was gradually ratified by the 12 founding Member States: Belgium, Denmark, France, the

Federal Republic of Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated between ...

, Greece, Italy, the Netherlands, Norway, Sweden, Switzerland, the United Kingdom, and

Yugoslavia Yugoslavia (; sh-Latn-Cyrl, separator=" / ", Jugoslavija, Југославија ; sl, Jugoslavija ; mk, Југославија ;; rup, Iugoslavia; hu, Jugoszlávia; rue, label=Pannonian Rusyn, Югославия, translit=Juhoslavija ...

Scientific achievements

Several important achievements in particle physics have been made through experiments at CERN. They include: *1973: The discovery of

neutral current Weak neutral current interactions are one of the ways in which subatomic particles can interact by means of the weak force. These interactions are mediated by the Z boson. The discovery of weak neutral currents was a significant step towa ...

s in the

Gargamelle Gargamelle was a heavy liquid bubble chamber detector in operation at CERN between 1970 and 1979. It was designed to detect neutrinos and antineutrinos, which were produced with a beam from the Proton Synchrotron (PS) between 1970 and 1976, ...

bubble chamber; *1983: The discovery of

W and Z bosons In particle physics, the W and Z bosons are vector bosons that are together known as the weak bosons or more generally as the intermediate vector bosons. These elementary particles mediate the weak interaction; the respective symbols are , , an ...

in the

UA1 The UA1 experiment (an abbreviation of Underground Area 1) was a high-energy physics experiment that ran at CERN's Proton-Antiproton Collider (SpS), a modification of the one-beam Super Proton Synchrotron (SPS). The data was recorded between 198 ...

and UA2 experiments; *1989: The determination of the number of light

neutrino A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass ...

families at the

Large Electron–Positron Collider The Large Electron–Positron Collider (LEP) was one of the largest particle accelerators ever constructed. It was built at CERN, a multi-national centre for research in nuclear and particle physics near Geneva, Switzerland. LEP collided elect ...

(LEP) operating on the Z boson peak; *1995: The first creation of antihydrogen atoms in the PS210 experiment; *1999: The discovery of direct

CP violation In particle physics, CP violation is a violation of CP-symmetry (or charge conjugation parity symmetry): the combination of C-symmetry (charge symmetry) and P-symmetry ( parity symmetry). CP-symmetry states that the laws of physics should be th ...

in the NA48 experiment; *2000: The Heavy Ion Programme discovered new state of matter, the

Quark Gluon Plasma A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly ...

. *2010: The isolation of 38 atoms of antihydrogen; *2011: Maintaining antihydrogen for over 15 minutes; *2012: A

boson In particle physics, a boson ( ) is a subatomic particle whose spin quantum number has an integer value (0,1,2 ...). Bosons form one of the two fundamental classes of subatomic particle, the other being fermions, which have odd half-integer spi ...

with mass around 125 GeV/c² consistent with the long-sought Higgs boson. In September 2011, CERN attracted media attention when the OPERA Collaboration reported the detection of possibly faster-than-light neutrinos. Further tests showed that the results were flawed due to an incorrectly connected

GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

synchronization cable. The 1984

Nobel Prize for Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

was awarded to

Carlo Rubbia Carlo Rubbia (born 31 March 1934) is an Italian particle physicist and inventor who shared the Nobel Prize in Physics in 1984 with Simon van der Meer for work leading to the discovery of the W and Z particles at CERN. Early life and educa ...

and

Simon van der Meer Simon van der Meer (24 November 19254 March 2011) was a Dutch particle accelerator physicist who shared the Nobel Prize in Physics in 1984 with Carlo Rubbia for contributions to the CERN project which led to the discovery of the W and Z part ...

for the developments that resulted in the discoveries of the W and Z bosons. The 1992 Nobel Prize for Physics was awarded to CERN staff researcher

Georges Charpak Georges Charpak (; born Jerzy Charpak, 1 August 1924 – 29 September 2010) was a Polish-born French physicist, who was awarded the Nobel Prize in Physics in 1992. Life Georges Charpak was born Jerzy Charpak to Jewish parents, Anna (Szapiro) and ...

"for his invention and development of particle detectors, in particular the

multiwire proportional chamber A wire chamber or multi-wire proportional chamber is a type of proportional counter that detects charged particles and photons and can give positional information on their trajectory, by tracking the trails of gaseous ionization. was located via ...

". The 2013 Nobel Prize for Physics was awarded to

François Englert François, Baron Englert (; born 6 November 1932) is a Belgian theoretical physicist and 2013 Nobel prize laureate. Englert is professor emeritus at the Université libre de Bruxelles (ULB), where he is a member of the Service de Physique Thé ...

and

Peter Higgs Peter Ware Higgs (born 29 May 1929) is a British theoretical physicist, Emeritus Professor in the University of Edinburgh,Griggs, Jessica (Summer 2008The Missing Piece ''Edit'' the University of Edinburgh Alumni Magazine, p. 17 and Nobel Prize ...

for the theoretical description of the Higgs mechanism in the year after the Higgs boson was found by CERN experiments.

Computer science

The

began as a CERN project named

ENQUIRE ENQUIRE was a software project written in 1980 by Tim Berners-Lee at CERN, which was the predecessor to the World Wide Web. It was a simple hypertext program that had some of the same ideas as the Web and the Semantic Web but was different in ...

, initiated by Tim Berners-Lee in 1989 and

Robert Cailliau Robert Cailliau (, born 26 January 1947) is a Belgian informatics engineer, computer scientist and author who proposed the first (pre-www) hypertext system for CERN in 1987 and collaborated with Tim Berners-Lee on the World Wide Web (jointly wi ...

in 1990. 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 intended to facilitate the sharing of information between researchers. The first website was activated in 1991. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone. A copy o
the original first webpage
created by Berners-Lee, is still published on the

World Wide Web Consortium The World Wide Web Consortium (W3C) is the main international standards organization for the World Wide Web. Founded in 1994 and led by Tim Berners-Lee, the consortium is made up of member organizations that maintain full-time staff working ...

's website as a historical document. Prior to the Web's development, CERN had pioneered the introduction of Internet technology, beginning in the early 1980s. More recently, CERN has become a facility for the development of grid computing, hosting projects including the

Enabling Grids for E-sciencE In psychotherapy and mental health, enabling has a positive sense of empowering individuals, or a negative sense of encouraging dysfunctional behavior.LHC Computing Grid. It also hosts the

CERN Internet Exchange Point The CERN Internet Exchange Point, or CIXP, is a historical European Internet landmark, through which the first pan-European Internet backbone and the first T1 connection to NSFnet were established in 1989 and 1990. CIXP is also member of the Eu ...

(CIXP), one of the two main

internet exchange point Internet exchange points (IXes or IXPs) are common grounds of IP networking, allowing participant Internet service providers (ISPs) to exchange data destined for their respective networks. IXPs are generally located at places with preexisting ...

s in Switzerland. CERN employs ten times more engineers and technicians than research physicists.

Particle accelerators

Current complex

CERN operates a network of seven accelerators and two decelerators, and some additional small accelerators. Each machine in the chain increases the energy of particle beams before delivering them to experiments or to the next more powerful accelerator (the decelerators naturally decrease the energy of particle beams before delivering them to experiments or further accelerators/decelerators). Currently (as of 2022) active machines are the LHC accelerator and: * The LINAC 3

linear accelerator A linear particle accelerator (often shortened to linac) is a type of particle accelerator that accelerates charged subatomic particles or ions to a high speed by subjecting them to a series of oscillating electric potentials along a linear ...

generating low energy particles. It provides heavy ions at 4.2 MeV/ u for injection into the Low Energy Ion Ring (LEIR). * The

Low Energy Ion Ring The Low Energy Ion Ring (LEIR) is a particle accelerator at CERN used to accelerate ions from the LINAC 3 to the Proton Synchrotron (PS) to provide ions for collisions within the Large Hadron Collider (LHC). History LEIR was converted from ...

(LEIR) accelerates the ions from the ion linear accelerator LINAC 3, before transferring them to the

Proton Synchrotron The Proton Synchrotron (PS, sometimes also referred to as CPS) is a particle accelerator at CERN. It is CERN's first synchrotron, beginning its operation in 1959. For a brief period the PS was the world's highest energy particle accelerator. It ...

(PS). This accelerator was commissioned in 2005, after having been reconfigured from the previous

Low Energy Antiproton Ring The Low Energy Anti-Proton Ring (LEAR) was a particle accelerator at CERN which operated from 1982 until 1996. The ring was designed to decelerate and store antiprotons, to study the properties of antimatter and to create atoms of antihydrogen. ...

(LEAR). * The Linac4

accelerates negative hydrogen ions to an energy of 160 MeV. The ions are then injected to the Proton Synchrotron Booster (PSB) where both electrons are then stripped from each of the hydrogen ions and thus only the nucleus containing one proton remains. The protons are then used in experiments or accelerated further in other CERN accelerators. Linac4 serves as the source of all proton beams for CERN experiments. * The Proton Synchrotron Booster increases the energy of particles generated by the proton linear accelerator before they are transferred to the other accelerators. * The 28

GeV GEV may refer to: * ''G.E.V.'' (board game), a tabletop game by Steve Jackson Games * Ashe County Airport, in North Carolina, United States * Gällivare Lapland Airport, in Sweden * Generalized extreme value distribution * Gev Sella, Israeli-Sou ...

(PS), built during 1954—1959 and still operating as a feeder to the more powerful SPS and to many of CERN's experiments. * 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 A compass is a device that shows the cardinal directions used for navigation and geographic orientation. It commonly consists of a magnetized needle or other element, such as a compass card or compass rose, which can pivot to align itself wit ...

and NA62), it has been operated as a proton–

antiproton The antiproton, , (pronounced ''p-bar'') is the antiparticle of the proton. Antiprotons are stable, but they are typically short-lived, since any collision with a proton will cause both particles to be annihilated in a burst of energy. The exis ...

collider A collider is a type of particle accelerator which brings two opposing particle beams together such that the particles collide. Colliders may either be ring accelerators or linear accelerators. Colliders are used as a research tool in particl ...

(the SpS collider), and for accelerating high energy

electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no ...

s and positrons which were injected into the

(LEP). Since 2008, it has been used to inject protons and

heavy ion High-energy nuclear physics studies the behavior of nuclear matter in energy regimes typical of high-energy physics. The primary focus of this field is the study of heavy-ion collisions, as compared to lighter atoms in other particle accelerat ...

s into the Large Hadron Collider (LHC). * The

On-Line Isotope Mass Separator The ISOLDE Radioactive Ion Beam Facility, is an on-line isotope separation, isotope separator facility located at the heart of the CERN accelerator complex on the Franco-Swiss border. The name of the facility is an acronym for Isotope 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. * The

Antiproton Decelerator The Antiproton Decelerator (AD) is a storage ring at the CERN laboratory near Geneva. It was built from the Antiproton Collector (AC) to be a successor to the Low Energy Antiproton Ring (LEAR) and started operation in the year 2000. Antiproto ...

(AD), which reduces the velocity of antiprotons to about 10% of the

speed of light The speed of light in vacuum, commonly denoted , is a universal physical constant that is important in many areas of physics. The speed of light is exactly equal to ). According to the special theory of relativity, is the upper limit ...

for research of

antimatter In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding particles in "ordinary" matter. Antimatter occurs in natural processes like cosmic ray collisions and some types of radioac ...

. The AD machine was reconfigured from the previous

Antiproton Collector The Antiproton Collector (AC) was part of the antiparticle factory at CERN designed to decelerate and store antimatter, to study the properties of antimatter and to create atoms of antihydrogen. It was built in 1986 around the existing Antiprot ...

(AC) machine. * The Extra Low Energy Antiproton ring (ELENA), which takes antiprotons from AD and decelerates them into low energies (speeds) for use in antimatter experiments. * The

AWAKE Wakefulness is a daily recurring brain state and state of consciousness in which an individual is conscious and engages in coherent cognitive and behavioral responses to the external world. Being awake is the opposite of being asleep, in which ...

experiment, which is a proof-of-principle plasma wakefield accelerator. * The CERN Linear Electron Accelerator for Research (CLEAR) accelerator research and development facility.

Large Hadron Collider

Many activities at CERN currently involve operating the Large Hadron Collider (LHC) and the experiments for it. The LHC represents a large-scale, worldwide scientific cooperation project. View inside detector at the CMS cavern LHC CERN

View inside detector at the CMS cavern LHC CERN

The LHC tunnel is located 100 metres underground, in the region between Geneva International Airport and the nearby Jura mountains. The majority of its length is on the French side of the border. It uses the 27 km circumference circular tunnel previously occupied by the

(LEP), which was shut down in November 2000. CERN's existing PS/SPS accelerator complexes are used to pre-accelerate protons and lead ions which are then injected into the LHC. Eight experiments (

CMS CMS may refer to: Computing * Call management system * CMS-2 (programming language), used by the United States Navy * Code Morphing Software, a technology used by Transmeta * Collection management system for a museum collection * Color manag ...

ATLAS An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geograp ...

LHCb The LHCb (Large Hadron Collider beauty) experiment is one of eight particle physics detector experiments collecting data at the Large Hadron Collider at CERN. LHCb is a specialized b-physics experiment, designed primarily to measure the paramet ...

, MoEDAL,

TOTEM A totem (from oj, ᑑᑌᒼ, italics=no or '' doodem'') is a spirit being, sacred object, or symbol that serves as an emblem of a group of people, such as a family, clan, lineage, or tribe, such as in the Anishinaabe clan system. While ''the ...

, LHCf, FASER and ALICE) are located along the collider; each of them studies particle collisions from a different aspect, and with different technologies. Construction for these experiments required an extraordinary engineering effort. For example, a special crane was rented from Belgium to lower pieces of the CMS detector into its 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 Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London, counted from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a cons ...

on 7 March 2005. The LHC has begun to generate vast quantities of data, which CERN streams to laboratories around the world for distributed processing (making use of a specialized

grid Grid, The Grid, or GRID may refer to: Common usage * Cattle grid or stock grid, a type of obstacle is used to prevent livestock from crossing the road * Grid reference, used to define a location on a map Arts, entertainment, and media * News ...

infrastructure, the LHC Computing Grid). During April 2005, a trial successfully streamed 600 MB/s to seven different sites across the world. The initial particle beams were injected into the LHC August 2008.Overbye, Dennis (29 July 2008).
Let the Proton Smashing Begin. (The Rap Is Already Written.)
. ''The New York Times''. The first beam was circulated through the entire LHC on 10 September 2008, but the system failed 10 days later because of a faulty magnet connection, and it was stopped for repairs on 19 September 2008. The LHC resumed operation on 20 November 2009 by successfully circulating two beams, each with an energy of 3.5 teraelectronvolts (TeV). The challenge for the engineers was then 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 Steve Myers, director for accelerators and technology. On 30 March 2010, the LHC successfully collided two proton beams with 3.5 TeV of energy per proton, resulting in a 7 TeV collision energy. However, this was just the start of what was needed for the expected discovery of the Higgs boson. When the 7 TeV experimental period ended, the LHC revved to 8 TeV (4 TeV per proton) starting March 2012, and soon began particle collisions at that energy. In July 2012, CERN scientists announced the discovery of a new sub-atomic particle that was later confirmed to be the Higgs boson. In March 2013, CERN announced that the measurements performed on the newly found particle allowed it to conclude that this is a Higgs boson. In early 2013, the LHC was deactivated for a two-year maintenance period, to strengthen the electrical connections between magnets inside the accelerator and for other upgrades. On 5 April 2015, after two years of maintenance and consolidation, the LHC restarted for a second run. The first ramp to the record-breaking energy of 6.5 TeV was performed on 10 April 2015. In 2016, the design collision rate was exceeded for the first time. A second two-year period of shutdown begun at the end of 2018.

Accelerators under construction

As of October 2019, the construction is on-going to upgrade the LHC's luminosity in a project called High Luminosity LHC (HL-LHC). This project should see the LHC accelerator upgraded by 2026 to an order of magnitude higher luminosity. As part of the HL-LHC upgrade project, also other CERN accelerators and their subsystems are receiving upgrades. Among other work, the LINAC 2 linear accelerator injector was decommissioned and replaced by a new injector accelerator, the LINAC4.

Decommissioned accelerators

* The original linear accelerator LINAC 1. Operated 1959–1992. * The LINAC 2 linear accelerator injector. Accelerated protons to 50

MeV In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacu ...

for injection into the Proton Synchrotron Booster (PSB). Operated 1978–2018. * The 600 MeV

Synchro-Cyclotron A synchrocyclotron is a special type of cyclotron, patented by Edwin McMillan in 1952, in which the frequency of the driving RF electric field is varied to compensate for relativistic effects as the particles' velocity begins to approach the sp ...

(SC) which started operation in 1957 and was shut down in 1991. Was made into a public exhibition in 2012–2013. * The

Intersecting Storage Rings The ISR (standing for "Intersecting Storage Rings") was a particle accelerator at CERN. It was the world's first hadron collider, and ran from 1971 to 1984, with a maximum center of mass energy of 62 GeV. From its initial startup, the collid ...

(ISR), an early collider built from 1966 to 1971 and operated until 1984. * The Super Proton–Antiproton Synchrotron (SpS), operated 1981–1991. A modification of Super Proton Synchrotron (SPS) to operate as a proton-antiproton collider. * The

(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 LEP Pre-Injector (LPI) accelerator complex, consisting of two accelerators, a linear accelerator called LEP Injector Linac (LIL; itself consisting of two back-to-back linear accelerators called LIL V and LIL W) and a circular accelerator called

Electron Positron Accumulator The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no k ...

(EPA). The purpose of these accelerators was to inject positron and electron beams into the CERN accelerator complex (more precisely, to the Proton Synchrotron), to be delivered to LEP after many stages of acceleration. Operational 1987–2001; after the shutdown of LEP and the completion of experiments that were directly feed by the LPI, the LPI facility was adapted to be used for the CLIC Test Facility 3 (CTF3). * The

(LEAR) was commissioned in 1982. LEAR assembled the first pieces of true

, in 1995, consisting of nine atoms of antihydrogen. It was closed in 1996, and superseded by the

. The LEAR apparatus itself was reconfigured into the

(LEIR) ion booster. * The

Antiproton Accumulator The Antiproton Accumulator (AA) was an infrastructure connected to the Proton–Antiproton Collider (SpS) – a modification of the Super Proton Synchrotron (SPS) – at CERN. The AA was built in 1979 and 1980, for the production and accumulati ...

(AA), built 1979–1980, operations ended in 1997 and the machine was dismantled. Stored antiprotons produced by the Proton Synchrotron (PS) for use in other experiments and accelerators (for example the ISR, SpS and LEAR). For later half of its working life operated in tandem with

(AC), to form the Antiproton Accumulation Complex (AAC). * The

(AC), built 1986–1987, operations ended in 1997 and the machine was converted into the

(AD), which is the successor machine for

(LEAR). Operated in tandem with

(AA) and the pair formed the Antiproton Accumulation Complex (AAC), whose purpose was to store antiprotons produced by the Proton Synchrotron (PS) for use in other experiments and accelerators, like the

(LEAR) and Super Proton–Antiproton Synchrotron (SpS). * The Compact Linear Collider Test Facility 3 (CTF3), which studied feasibility for the future normal conducting linear collider project (the CLIC collider). In operation 2001–2016. One of its beamlines has been converted, from 2017 on, into the new CERN Linear Electron Accelerator for Research (CLEAR) facility.

Possible future accelerators

CERN, in collaboration with groups worldwide, is investigating two main concepts for future accelerators: A linear electron-positron collider with a new acceleration concept to increase the energy ( CLIC) and a larger version of the LHC, a project currently named

Future Circular Collider The Future Circular Collider (FCC) is a proposed particle accelerator with an energy significantly above that of previous circular colliders, such as the Super Proton Synchrotron, the Tevatron, and the Large Hadron Collider (LHC). The FCC pro ...

Sites

The smaller accelerators are on the main

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. 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

, UA2 and the LEP experiments (the latter are used by 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 so-called " charmed" particles and located at the Prévessin (North Area) site while WA22 used the

Big European Bubble Chamber The Big European Bubble Chamber (BEBC) is a large detector formerly used to study particle physics at CERN. The chamber body, a stainless-steel vessel, was filled with 35 cubic metres of superheated liquid hydrogen, liquid deuterium, or a neon-h ...

(BEBC) at the Meyrin (West Area) site to examine neutrino interactions. The

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 Meyrin and Prévessin sites are named after famous physicists, such as

Wolfgang Pauli Wolfgang Ernst Pauli (; ; 25 April 1900 – 15 December 1958) was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after having been nominated by Albert Einstein, Pauli received the Nobel Prize in Physics ...

, who pushed for CERN's creation. Other notable names are Richard Feynman,

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

, and Bohr.

Participation and funding

Member states and budget

Since its foundation by 12 members in 1954, CERN regularly accepted new members. All new members have remained in the organization 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 quit in 1961. Of the 23 members, Israel joined CERN as a full member on 6 January 2014, becoming the first (and currently only) non-European full member. The budget contributions of member states are computed based on their GDP.

Enlargement

Associate Members, Candidates: * Turkey signed an association agreement on 12 May 2014 and became an associate member on 6 May 2015. *Pakistan signed an association agreement on 19 December 2014 and became an associate member on 31 July 2015. * Cyprus signed an association agreement on 5 October 2012 and became an associate Member in the pre-stage to membership on 1 April 2016. * Ukraine signed an association agreement on 3 October 2013. The agreement was ratified on 5 October 2016. * India signed an association agreement on 21 November 2016. The agreement was ratified on 16 January 2017. * Slovenia was approved for admission as an Associate Member state in the pre-stage to membership on 16 December 2016. The agreement was ratified on 4 July 2017. * Lithuania was approved for admission as an Associate Member state on 16 June 2017. The association agreement was signed on 27 June 2017 and ratified on 8 January 2018. * Croatia was approved for admission as an Associate Member state on 28 February 2019. The agreement was ratified on 10 October 2019. *Estonia was approved for admission as an Associate Member in the pre-stage to membership state on 19 June 2020. The agreement was ratified on 1 February 2021. *Latvia and CERN signed an associate membership agreement on 14 April 2021. Latvia was formally admitted as an Associate Member on 2 August 2021.

International relations

Three countries have observer status: * Japan – since 1995 * Russia – since 1993 (suspended as of March 2022 ) * United States – since 1997 Also observers are the following international organizations: * UNESCO – since 1954 *

European Commission The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body ...

– since 1985 *

JINR The Joint Institute for Nuclear Research (JINR, russian: Объединённый институт ядерных исследований, ОИЯИ), in Dubna, Moscow Oblast (110 km north of Moscow), Russia, is an international research ce ...

– since 2014 (suspended as of March 2022 ) Non-Member States (with dates of Co-operation Agreements) currently involved in CERN programmes are: CERN also has scientific contacts with the following other countries: International research institutions, such as CERN, can aid in science diplomacy.

Associated institutions

A large number of institutes around the world are associated to CERN through current collaboration agreements and/or historical links. The list below contains organizations represented as observers to the CERN Council, organizations to which CERN is an observer and organizations based on the CERN model: *

European Molecular Biology Laboratory The European Molecular Biology Laboratory (EMBL) is an intergovernmental organization dedicated to molecular biology research and is supported by 27 member states, two prospect states, and one associate member state. EMBL was created in 1974 and ...

, organization based on the CERN model *

European Space Research Organisation The European Space Research Organisation (ESRO) was an international organisation founded by 10 European nations with the intention of jointly pursuing scientific research in space. It was founded in 1964. As an organisation ESRO was based on a ...

(since 1975

ESA , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (120 ...

), organization based on the CERN model * European Southern Observatory, organization based on the CERN model *

, observer to CERN Council, CERN is represented in the JINR Council * SESAME, CERN is an observer to the SESAME Council *

UNESCO The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It ...

, observer to CERN Council

Open science

The Open Science movement focuses on making scientific research openly accessible and on creating knowledge through open tools and processes. Open access,

open data Open data is data that is openly accessible, exploitable, editable and shared by anyone for any purpose. Open data is licensed under an open license. The goals of the open data movement are similar to those of other "open(-source)" movement ...

open source software Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open ...

and hardware,

open licenses A free license or open license is a license which allows others to reuse another creator’s work as they wish. Without a special license, these uses are normally prohibited by copyright, patent or commercial license. Most free licenses are wo ...

digital preservation In library and archival science, digital preservation is a formal endeavor to ensure that digital information of continuing value remains accessible and usable. It involves planning, resource allocation, and application of preservation methods and ...

and reproducible research are primary components of open science and areas in which CERN has been working towards since its formation. CERN has developed a number of policies and official documents that enable and promote open science, starting with CERN's founding convention in 1953 which indicated that all its results are to be published or made generally available. Since then, CERN published its open access policy in 2014, which ensures that all publications by CERN authors will be published with

gold open access Open access (OA) is a set of principles and a range of practices through which research outputs are distributed online, free of access charges or other barriers. With open access strictly defined (according to the 2001 definition), or Gratis v ...

and most recently an open data policy that was endorsed by the four main LHC collaborations ( ALICE,

and

). The open data policy complements the open access policy, addressing the public release of scientific data collected by LHC experiments after a suitable embargo period. Prior to this open data policy, guidelines for data preservation, access and reuse were implemented by each collaboration individually through their own policies which are updated when necessary. The European Strategy for Particle Physics, a document mandated by the CERN Council that forms the cornerstone of Europe's decision-making for the future of particle physics, was last updated in 2020 and strongly affirmed the organisation's role within the open science landscape by stating: “The particle physics community should work with the relevant authorities to help shape the emerging consensus on open science to be adopted for publicly-funded research, and should then implement a policy of open science for the field”. Beyond the policy level, CERN has established a variety of services and tools to enable and guide open science at CERN, and in particle physics more generally. On the publishing side, CERN has initiated and operates a global cooperative project, the Sponsoring Consortium for Open Access Publishing in Particle Physics, SCOAP3, to convert scientific articles in high-energy physics to open access. Currently, the SCOAP3 partnership represents 3000+ libraries from 44 countries and 3 intergovernmental organizations who have worked collectively to convert research articles in high-energy physics across 11 leading journals in the discipline to open access. Public-facing results can be served by various CERN-based services depending on their use case: th
CERN Open Data portal

Zenodo Zenodo is a general-purpose open repository developed under the European OpenAIRE program and operated by CERN. It allows researchers to deposit research papers, data sets, research software, reports, and any other research related digital artef ...

, th
CERN Document Server

INSPIRE The following is a thematic list of European Union directives: For a date based list, see the :European Union directives by number Numbering From 1 January 1992 to 31 December 2014, numbers assigned by the General Secretariat of the Council ...

an
HEPData
are the core services used by the researchers and community at CERN, as well as the wider high-energy physics community for the publication of their documents, data, software, multimedia, etc. CERN's efforts towards preservation and reproducible research are best represented by a suite of services addressing the entire physics analysis lifecycle (such as data, software and computing environment)
CERN Analysis Preservation
helps researchers to preserve and document the various components of their physics analyses
REANA
(Reusable Analyses) enables the instantiating of preserved research data analyses on the cloud. All of the abovementioned services are built using

and strive towards compliance with best effort principles where appropriate and where possible, such as the FAIR principles, the FORCE11 guidelines and

Plan S Plan S is an initiative for open-access science publishing launched in 2018 by "cOAlition S", a consortium of national research agencies and funders from twelve European countries. The plan requires scientists and researchers who benefit from s ...

, while at the same time taking into account relevant activities carried out by the

Public exhibits

Facilities at CERN open to the public include: *

The Globe of Science and Innovation The Globe of Science and Innovation is a visitor center, designed to inform visitors about the significant research being carried out at CERN. The wooden structure, which is high and in diameter, is a symbol of planet earth and was originally b ...

, which opened in late 2005 and is used four times a week for special exhibits. *The Microcosm museum on

and CERN history. CERN also provides daily tours to certain facilities such as the Synchro-cyclotron (CERNs first particle accelerator) and the superconducting magnet workshop. In 2004, a 2-m statue of the

Nataraja Nataraja () also known as Adalvallaan () is a depiction of the Hindu deities, Hindu god Shiva as the divine cosmic dancer. His dance is called Tandava.''Encyclopædia Britannica'' (2015) The pose and artwork are described in many Hindu texts ...

, the dancing form of the Hindu god

Shiva Shiva (; sa, शिव, lit=The Auspicious One, Śiva ), also known as Mahadeva (; ɐɦaːd̪eːʋɐ, or Hara, is one of the principal deities of Hinduism. He is the Supreme Being in Shaivism, one of the major traditions within Hindu ...

, was unveiled at CERN. The statue, symbolizing Shiva's cosmic dance of creation and destruction, was presented by the

Indian government The Government of India (ISO: ; often abbreviated as GoI), known as the Union Government or Central Government but often simply as the Centre, is the national government of the Republic of India, a federal democracy located in South Asia, ...

to celebrate the research center's long association with India. A special plaque next to the statue explains the metaphor of Shiva's cosmic dance with quotations from physicist

Fritjof Capra Fritjof Capra (born February 1, 1939) is an Austrian-born American physicist, systems theorist and deep ecologist. In 1995, he became a founding director of the Center for Ecoliteracy in Berkeley, California. He is on the faculty of Schumacher ...

Hundreds of years ago, Indian artists created visual images of dancing Shivas in a beautiful series of bronzes. In our time, physicists have used the most advanced technology to portray the patterns of the cosmic dance. The metaphor of the cosmic dance thus unifies ancient mythology, religious art and modern physics.

In popular culture

Shiva's statue at CERN engaging in the Nataraja dance

*The band

Les Horribles Cernettes ''Les Horribles Cernettes'' (, "The Horrible CERN Girls") was an all-female parody pop group, self-labelled "the one and only High Energy Rock Band", which was founded by employees of CERN and performed at CERN and other HEP-related events. Their ...

was founded by women from CERN. The name was chosen so to have the same initials as the LHC. * The science journalist Katherine McAlpine made a

rap Rapping (also rhyming, spitting, emceeing or MCing) is a musical form of vocal delivery that incorporates "rhyme, rhythmic speech, and street vernacular". It is performed or chanted, usually over a backing beat or musical accompaniment. The ...

video called "Large Hadron Rap" about CERN's Large Hadron Collider with some of the facility's staff. * '' Particle Fever'', a 2013 documentary, explores CERN throughout the inside and depicts the events surrounding the 2012 discovery of the Higgs Boson. * John Titor, a self-proclaimed

time travel Time travel is the concept of movement between certain points in time, analogous to movement between different points in space by an object or a person, typically with the use of a hypothetical device known as a time machine. Time travel is a ...

er, alleged that CERN would invent time travel in 2001. * CERN is depicted in the

visual novel A , often abbreviated as VN, is a form of digital semi-interactive fiction. Visual novels are often associated with and used in the medium of video games, but are not always labeled as such themselves. They combine a textual narrative with sta ...

anime is hand-drawn and computer-generated animation originating from Japan. Outside of Japan and in English, ''anime'' refers specifically to animation produced in Japan. However, in Japan and in Japanese, (a term derived from a shortening of ...

series '' Steins;Gate'' as SERN, a shadowy organization that has been researching time travel in order to restructure and control the world. * In

Robert J. Sawyer Robert James Sawyer (born April 29, 1960) is a Canadian science fiction writer. He has had 24 novels published and his short fiction has appeared in ''Analog Science Fiction and Fact'', ''Amazing Stories'', '' On Spec'', ''Nature'', and numerou ...

's 1999 science fiction novel '' Flashforward'', as CERN's Large Hadron Collider accelerator is performing a run to search for the Higgs boson the entire human race sees themselves twenty-one years and six months in the future. * In

Dan Brown Daniel Gerhard Brown (born June 22, 1964) is an American author best known for his thriller novels, including the Robert Langdon novels ''Angels & Demons'' (2000), '' The Da Vinci Code'' (2003), ''The Lost Symbol'' (2009), '' Inferno'' (2013), ...

's 2000 mystery-thriller novel ''

Angels & Demons ''Angels & Demons'' is a 2000 bestselling mystery- thriller novel written by American author Dan Brown and published by Pocket Books and then by Corgi Books. The novel introduces the character Robert Langdon, who recurs as the protagonist of B ...

'' and 2009 film of the same name, a canister of antimatter is stolen from CERN. * CERN is depicted in a 2009 episode of '' South Park'' (Season 13, Episode 6), " 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. *In the 2010 season 3 episode 15 of the TV sitcom ''

The Big Bang Theory ''The Big Bang Theory'' is an American television sitcom created by Chuck Lorre and Bill Prady, both of whom served as executive producers on the series, along with Steven Molaro, all of whom also served as head writers. It premiered on C ...

'', "The Large Hadron Collision",

Leonard Leonard or ''Leo'' is a common English masculine given name and a surname. The given name and surname originate from the Old High German ''Leonhard'' containing the prefix ''levon'' ("lion") from the Greek Λέων ("lion") through the Latin '' L ...

and Raj travel to CERN to attend a conference and see the LHC. *The 2012 student film ''

Decay Decay may refer to: Science and technology * Bit decay, in computing * Software decay, in computing * Distance decay, in geography * Decay time (fall time), in electronics Biology * Decomposition of organic matter * Tooth decay (dental caries ...

'', which centers on the idea of the Large Hadron Collider transforming people into zombies, was filmed on location in CERN's maintenance tunnels. * The Compact Muon Solenoid at CERN was used as the basis for the Megadeth's ''Super Collider'' album cover. * CERN forms part of the back story of the

massively multiplayer A massively multiplayer online game (MMOG or more commonly MMO) is an online video game with a large number of players, often hundreds or thousands, on the same server. MMOs usually feature a huge, persistent world, persistent open world, alt ...

augmented reality game ''

Ingress Ingress may refer to: Science and technology * Ingress (signal leakage), the passage of an outside signal into a coaxial cable * Ingress filtering, a computer network packet filtering technique * Ingress protection rating, a protection level that ...

'', and in the 2018 Japanese anime television series '' Ingress: The Animation'', based on Niantic's augmented reality mobile game of the same name. * In 2015, Sarah Charley, US communications manager for LHC experiments at CERN with graduate students Jesse Heilman of the

University of California, Riverside The University of California, Riverside (UCR or UC Riverside) is a public land-grant research university in Riverside, California. It is one of the ten campuses of the University of California system. The main campus sits on in a suburban distr ...

, and Tom Perry and Laser Seymour Kaplan of the

University of Wisconsin, Madison A university () is an educational institution, institution of higher education, higher (or Tertiary education, tertiary) education and research which awards academic degrees in several Discipline (academia), academic disciplines. Universities ty ...

created a parody video based on " Collide", a song by American artist

Howie Day Howard Kern Day is an American singer-songwriter. Beginning his career as a solo artist in the late 1990s, Day became known for his extensive touring and in-concert use of samplers and effects pedals to accompany himself. He self-financed and s ...

. The lyrics were changed to be from the perspective of a proton in the Large Hadron Collider. After seeing the parody, Day re-recorded the song with the new lyrics, and released a new version of "Collide" in February 2017 with a video created during his visit to CERN. * In 2015,

Ryoji Ikeda Ryoji Ikeda (池田亮司 ''Ikeda Ryōji'', born 1966) is a Japanese visual and sound artist who currently lives and works in Paris, France. Ikeda's music is concerned primarily with sound in a variety of "raw" states, such as sine tones and noi ...

created an art installation called "Supersymmetry" based on his experience as a resident artist at CERN. * The television series

Mr. Robot ''Mr. Robot'' is an American drama thriller television series created by Sam Esmail for USA Network. It stars Rami Malek as Elliot Alderson, a cybersecurity engineer and hacker with social anxiety disorder, clinical depression and dissociati ...

features a secretive, underground project apparatus that resembles the

ATLAS experiment ATLAS is the largest general-purpose particle detector experiment at the Large Hadron Collider (LHC), a particle accelerator at CERN (the European Organization for Nuclear Research) in Switzerland. The experiment is designed to take advantage of ...

References

External links

*
''The emerald city – CERN at 50''
by The Economist
''CERN Courier'' – International journal of high-energy physics

''Big Bang Day: The Making of CERN''
September 2008, A BBC Radio program {{Coord, 46, 14, 03, N, 6, 03, 10, E, region:CH_type:landmark, display=title International organizations based in Europe International research institutes Meyrin Nuclear research institutes Organisations based in Geneva Organizations established in 1954 Particle physics facilities Physics institutes Research institutes in Switzerland Research institutes in France Science and technology in Europe Science diplomacy