BIG SCIENCE costs big money. And there are few places where science is bigger than at CERN, the world’s largest particle physics laboratory, near Geneva. There, physicists have constructed a machine the size of a small city – a circular particle accelerator 27 kilometres in circumference occupying a tunnel 100 metres underground. The machine is the Large Electron Positron collider (LEP), which was built in the 1980s at a cost of £700 million. It is designed to smash electrons into their antimatter counterparts, positrons, at energies large enough to create vast numbers of a subatomic particle known as the Z0 boson. The results of experiments on this exotic particle have answered fundamental questions about our Universe.
The researchers at CERN now want to study a particle known as the W boson, which will further improve their understanding of the subatomic world. W bosons have about the same mass as Z0 bosons but must be produced in pairs at LEP, which means that twice as much energy will be needed to create them. Physicists are also searching for a particle known as the Higgs boson, whose existence would explain why matter has mass. However, its own mass is unknown. Physicists believe that increasing the power of their accelerator will give them a better chance of discovering the Higgs particle.
This change of role for LEP has always been on the cards, and it was designed to be upgraded. In the next century the tunnel that contains it could even house a more powerful accelerator, the Large Hadron Collider (LHC), that is now on the drawing board (see…
