CERN, the European Laboratory for Particle Physics, undertakes research into the structure of matter. This research is largely performed by teams of visiting scientists based at their parent university or research centre in Europe. CERN staff are drawn from 19 European Member States, but scientists from any country may be invited to spend a limited period at CERN. CERN has 2,800 staff members and some 6,500 visiting scientists from all over the world carry out research at CERN each year.
Research is carried out with the help of three large accelerators, a Proton Synchrotron (PS) of 28 GeV, the Super Proton Synchrotron (SPS) of 450 GeV and, the Large Electron-Positron collider (LEP). LEP came into operation at 50 GeV per beam in July 1989, moved up to 70 GeV per beam towards the end of 1995, and to 92 GeV per beam in July 1997. LEP has four associated large experimental facilities which have established, among other things, that there are three light neutrino types. The SPS a large experimental area for fixed-target experiments at some distance from the accelerator. CERN is preparing to install a proton-proton collider inside the LEP tunnel. This is the Large Hadron Collider (LHC) which was given the go-ahead at the end of 1994. The LHC will achieve collisions at 14 TeV using superconducting magnets to keep the particle beams in orbit. An intensive R&D programme is underway for both machine and detector components.
The prime function of the Laboratory is to provide Europe's particle physicists with world class research facilities which could not be obtained within the resources of individual countries. Development work goes on continuously to improve the accelerators, detection systems and other auxiliary installations, and the range of equipment available at CERN is among the finest assembled at any site in the world.