Collider

A collider is a type of particle accelerator involving directed beams of particles. Colliders may either be ring accelerators or linear accelerators, and may collide a single beam of particles against a stationary target or two beams head-on.

Colliders are used as a research tool in particle physics by accelerating particles to very high kinetic energy and letting them impact other particles. Analysis of the byproducts of these collisions gives scientists good evidence of the structure of the subatomic world and the laws of nature governing it. These may become apparent only at high energies and for tiny periods of time, and therefore may be hard or impossible to study in other ways.

Explanation

In particle physics one gains knowledge about elementary particles by accelerating particles to very high kinetic energy and letting them impact on other particles. For sufficiently high energy, a reaction happens that transforms the particles into other particles. Detecting these products gives insight into the physics involved.