The European Organization for Nuclear Research
(French: Organisation européenne pour la
recherche nucléaire), known as CERN (; French
pronunciation: ​[sɛʁn]; derived from the
name Conseil européen pour la recherche nucléaire),
is a European research organization that operates
the largest particle physics laboratory in
the world.
Established in 1954, the organization is based
in a northwest suburb of Geneva on the Franco–Swiss
border, and has 23 member states.
Israel is the only non-European country granted
full membership.
CERN is an official United Nations Observer.The
acronym CERN is also used to refer to the
laboratory, which in 2016 had 2,500 scientific,
technical, and administrative staff members,
and hosted about 12,000 users.
In the same year, CERN generated 49 petabytes
of data.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 through international collaborations.
The main site at Meyrin hosts a large computing
facility, which is primarily used to store
and analyse data from experiments, as well
as simulate events.
Researchers need remote access to these facilities,
so the lab has historically been a major wide
area network hub.
CERN is also the birthplace of the World Wide
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 Conseil Européen pour la
Recherche Nucléaire (European Council for
Nuclear Research), which was a provisional
council for building 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.
According to Lew Kowarski, a former director
of CERN, when the name was changed, the abbreviation
could have become the awkward OERN, and Heisenberg
said that this could "still be CERN even if
the name is [not]".CERN's first president
was Sir Benjamin Lockspeiser.
Edoardo Amaldi was the general secretary of
CERN at its early stages when operations were
still provisional, while the first Director-General
(1954) was Felix Bloch.The laboratory was
originally devoted to the study of atomic
nuclei, 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 (Laboratoire européen
pour la physique des particules), 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, Greece,
Italy, the Netherlands, Norway, Sweden, Switzerland,
the United Kingdom, and Yugoslavia.
=== Scientific achievements ===
Several important achievements in particle
physics have been made through experiments
at CERN.
They include:
1973: The discovery of neutral currents in
the Gargamelle bubble chamber;
1983: The discovery of W and Z bosons in the
UA1 and UA2 experiments;
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;
1999: The discovery of direct CP violation
in the NA48 experiment;
2010: The isolation of 38 atoms of antihydrogen;
2011: Maintaining antihydrogen for over 15
minutes;
2012: A boson 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
synchronization cable.The 1984 Nobel Prize
for Physics was awarded to Carlo Rubbia and
Simon van der Meer 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 "for
his invention and development of particle
detectors, in particular the multiwire proportional
chamber".
The 2013 Nobel Prize for physics was awarded
to François Englert and Peter Higgs for the
theoretical description of the Higgs mechanism
in the year after the Higgs boson was found
by CERN experiments.
==== Computer science ====
The World Wide Web began as a CERN project
named ENQUIRE, initiated by Tim Berners-Lee
in 1989 and Robert Cailliau 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 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 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 (EGEE) and LHC
Computing Grid.
It also hosts the CERN Internet Exchange Point
(CIXP), one of the two main internet exchange
points in Switzerland.
== Particle accelerators ==
=== 
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.
LINAC 2 accelerates protons to 50 MeV for
injection into the Proton Synchrotron Booster
(PSB), and LINAC 3 provides heavy ions at
4.2 MeV/u for injection into the Low Energy
Ion Ring (LEIR).
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
during 1954—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.
The Antiproton Decelerator (AD), which reduces
the velocity of antiprotons to about 10% of
the speed of light for research of antimatter.
The Compact Linear Collider Test Facility,
which studies feasibility for the future normal
conducting linear collider project.
The AWAKE experiment, which is a proof-of-principle
plasma wakefield accelerator.
==== 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.
The LHC tunnel is located 100 metres underground,
in the region between the 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 Large Electron–Positron
Collider (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.
Seven experiments (CMS, ATLAS, LHCb, MoEDAL,
TOTEM, LHC-forward 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 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.
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 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.
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 is scheduled
to begin at the end of 2018.
=== 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.
=== 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.
== 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.
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 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 (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 Meyrin and Prévessin
sites are named after famous physicists, such
as Richard Feynman, Niels Bohr, and Albert
Einstein.
== 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.
=== International relations ===
Three countries have observer status:
Also observers are the following international
organizations:
UNESCO – since 1954
European Commission – since 1985
JINR - since 2014Non-Member States (with dates
of Co-operation Agreements) currently involved
in CERN programmes are:
CERN also has scientific contacts with the
following countries:
International research institutions, such
as CERN, can aid in science diplomacy.
=== Associated institutions ===
European Southern Observatory
Swiss National Supercomputing Centre
== 
Open access publishing ==
CERN has initiated an open access publishing
project to convert scientific articles in
high energy physics into gold open access
by redirecting subscription fees.
In the first phase from 2014-2016 3,000 libraries,
consortia, research organisations, publishers
and funding agencies in various countries
participated.
All publications by CERN authors are published
with gold open access.
== 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.CERN also provides daily tours
to certain facilities such as the Synchro-cyclotron
(CERNs first particle accelerator) and the
superconducting magnet workshop.
== In popular culture ==
The band Les Horribles Cernettes was founded
by women from CERN.
The name was chosen so to have the same initials
as the LHC.
CERN's Large Hadron Collider is the subject
of a (scientifically accurate) rap video starring
Katherine McAlpine 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
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.
John Titor, a self-proclaimed time traveler,
alleged that CERN would invent time travel
in 2001.
CERN is depicted in the visual novel/anime
series Steins;Gate as SERN, a shadowy organization
that has been researching time travel in order
to restructure and control the world.
In Dan Brown's mystery-thriller novel Angels
& Demons and film of the same name, a canister
of antimatter is stolen from CERN.
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, 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.
In season 3 episode 15 of the TV sitcom The
Big Bang Theory titled "The Large Hadron Collision",
Leonard and Raj travel to CERN to attend a
conference and see the LHC.
The 2012 student film Decay, 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.
In Super Lovers, Haruko (Ren's mother) worked
at CERN, and Ren was taught by CERN professors
CERN forms part of the back story of the massively
multiplayer augmented reality game Ingress.
In season 10 episode 6 of the BBC TV show
Doctor Who titled "Extremis", CERN and its
physicists are involved in a mysterious plot
involving a book that causes everyone who
reads it to kill themselves.
In 2015, Sarah Charley, US communications
manager for LHC experiments at CERN with graduate
students Jesse Heilman of the University of
California, Riverside, and Tom Perry and Laser
Seymour Kaplan of the University of Wisconsin,
Madison created a parody video of “Collide”
a song by American artist Howie Day.
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 in February,
2017 Day released this new version of "Collide"
in a video created during his visit to CERN.
== See also ==
CERN portal
