List of accelerators in particle physics

A list of particle accelerators used for particle physics experiments. Some early particle accelerators that more properly did nuclear physics, but existed prior to the separation of particle physics from that field, are also included. Although a modern accelerator complex usually has several stages of accelerators, only accelerators whose output has been used directly for experiments are listed.

Early accelerators
These all used single beams with fixed targets. They tended to have very briefly run, inexpensive, and unnamed experiments.

Cyclotrons
[1] The magnetic pole pieces and return yoke from the 60-inch cyclotron were later moved to UC Davis and incorporated into a 76-inch isochronous cyclotron which is still in use today

Fixed-target accelerators
More modern accelerators that were also run in fixed target mode; often, they will also have been run as colliders, or accelerated particles for use in subsequently built colliders.

Hypothetical accelerators
Besides the real accelerators listed above, there are hypothetical accelerators often used as hypothetical examples or optimistic projects by particle physicists.
 * Eloisatron (Eurasiatic Long Intersecting Storage Accelerator) was a project of INFN headed by Antonio Zichichi at the Ettore Majorana Foundation and Centre for Scientific Culture in Erice, Sicily. The center-of-mass energy was planned to be 200 TeV, and the size was planned to span parts of Europe and Asia.
 * Fermitron was an accelerator sketched by Enrico Fermi on a notepad in the 1940s proposing an accelerator in stable orbit around the Earth.
 * The undulator radiation collider is a design for an accelerator with a center-of-mass energy around the GUT scale. It would be light-weeks across and require the construction of a Dyson swarm around the Sun.
 * Planckatron is an accelerator with a center-of-mass energy of the order of the Planck scale. It is estimated that the radius of the Planckatron would have to be roughly the radius of the Milky Way. It would require so much energy to run that it could only be built by at least a Kardashev Type II civilization.
 * Arguably also in this category falls the Zevatron, a hypothetical source for observed ultra-high-energy cosmic rays.