Particle Detectors

Particle detectors are like electronic eyes. They allow physicists to see the results of particle collisions by tracking the particles that emerge. Physicists refer to collisions and their aftermaths as events.

Each of LEP's four detectors was built in the form of a giant cylinder, about the size of a three floor building and constructed like a Russian doll. In particle detectors, each layer of the cylinder has a specific task to perform, some measure the particles' tracks, others measure their energies. By combining the evidence from different layers, physicists are able to learn a lot about the particles emerging from collisions.

The four LEP detectors.