Particle accelerator

A particle accelerator is a device that uses electric and/or magnetic fields to propel electrically charged particles to high speeds.

High Energy Machines

High energy accelerators use a linear array of plates (or drift tubes) to which an alternating high energy field is applied. As the particles approach a plate they are accelerated towards it by an opposite polarity charge applied to the plate. As they pass through a hole in the plate, the polarity is switched so that the plate now repels them and they are now accelerated by it towards the next plate. Normally a stream of "bunches" of particles are accelerated, so a carefully controlled AC voltage is applied to each plate to continuously repeat this for each bunch.

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As the particles approach the speed of light the switching rate of the electric fields becomes so high that they operate at microwave frequencies, and so RF cavity resonators are used in higher energy machines instead of simple plates.

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In an X-ray generator, the target itself is one of the electrodes. DC accelerator types capable of accelerating particles to speeds sufficient to cause nuclear reactions are Cockcroft-Walton generators or voltage multipliers that convert AC to high voltage DC and Van de Graaff generators that use static electricity carried by belts.

Related Topics:
Cockcroft-Walton generator - Voltage multiplier - Van de Graaff generator

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The largest and most powerful particle accelerators, such as the RHIC, the LHC (scheduled to start operation in 2007) and the Tevatron, are used for experimental particle physics.

Related Topics:
RHIC - LHC - Tevatron - Experiment - Particle physics

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Particle Accelerators can also produce proton beams, which can produce "proton-heavy" medical or research isotopes as opposed to the "neutron-heavy" ones made in reactors. An example of this type of machine is LANSCE at Los Alamos

Related Topics:
Isotopes - Los Alamos

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