At the energies achieved today, the collisions, or events, produce many different particles, most of which have lifetimes so short that they leave no detectable tracks before decaying. Physicists deduce these particle’s existence from measuring their decay products. Large, multi-component detectors are built, each component designed to test different aspects of the event. In particular, they measure position, energy, momentum and distinguish different particle types.

Particles produced in fixed target experiments generally fly in the forward direction. For this reason, detectors in these machines are generally positioned downstream from the target and are cone-shaped, the pointed end of the cone being nearest the target. Particles produced in colliding beam experiments travel in all directions. Hence, detectors tend to take the form of long cylinders around the part of the beam pipe in which the event occurs.

The components of a detector are arranged in order such that all particles can travel to their relevant part(s) of the detector as undisturbed as possible. A typical array comprises the following:

Tracking detectors set up nearest the event measure to the position of particles. A magnetic coil outside the tracking detector to bend the particle tracks to determine momentum. Then come the Cerenkov detectors which measure the particles’ velocity. EM- and Hadron Calorimeters beyond these measure energy and finally muon detectors (to detect muons).

All rely on the electromagnetic interaction, reducing the problem to looking at charged particles and photons (the carriers of the EM force).

  • Accelerators
  • The first accelerators
  • R-F Cavities
  • Fixed target and colliding beam accelerators
  • Focusing the particle beams
  • Linear Accelerators
  • Synchrotrons
  • Detectors