What is CERN?

A laboratory for the world
CERN is the European Laboratory for Particle Physics, one of the world's most prestigious research centres. Its business is fundamental physics - finding out what makes our universe work, where it came from and where it is going. At CERN, some of the world's biggest and most complex machines are used to study nature's tiniest building blocks, the fundamental particles. By colliding these minute particles of matter physicists unravel the basic laws of nature.


At work on the LEP accelerator.
The Laboratory provides state-of-the-art scientific facilities for researchers to use. These are accelerators that accelerate tiny particles to a fraction under the speed of light and detectors like electronic eyes that make the particles visible.

CERN's accelerator complex is built around three principal inter-dependent accelerators. The oldest, the Proton

Synchrotron (PS), was built in the 1950s and was briefly the world's highest energy accelerator. The Super Proton Synchrotron (SPS), built in the 1970s, was the scene of CERN's first Nobel prize in the 1980s. The Large Electron-Positron collider (LEP) is the Laboratory's current flagship, it came on stream in 1989. LEP is an enormous machine. Built in a circular underground tunnel it is 27 kilometres around and weighs over 23 000 tonnes.

CERN is currently preparing to install a new accelerator inside the same tunnel as LEP. Called the Large Hadron Collider (LHC), this machine will start-up in 2005 giving the world's physicists a new tool to probe deeper than ever into the heart of matter. Each of CERN's accelerators plays host to a range of experiments run by collaborations of physicists from around the world. These physicists build particle detectors at their home institutes and bring them to CERN to record the results of particle collisions.
The L3 detector, one of four detectors at LEP.

CERN was founded in 1954 as one of Europe's first joint ventures. Since then it has become a shining example of international collaboration. From the original 12 signatories of the CERN convention membership has grown to 20 Member States. The Laboratory sits astride the Franco-Swiss border west of Geneva at the foot of the Jura mountains. Some 7000 scientists, over half the world's particle
physicists, use CERN's facilities. They represent some 500 universities and over 80 nationalities.


The terrace of CERN's cafeteria, a place for work as well as relaxation.


Particle Physics Education CD-ROM 1999 CERN