A particle accelerator is a machine that uses electromagnetic fields to propel ions to very high speeds and energies to contain them in well-defined beams. Small accelerators are used for fundamental
The Tevatron (background circle), a synchrotron collider type particle accelerator at Fermi National Accelerator Laboratory (Fermilab), Batavia, Illinois, USA. Shut down in 2011, until 2007 it was the most powerful particle accelerator in the world, accelerating protons to an energy of over 1 TeV (tera electron volts). Beams of protons and antiprotons, circulating in opposite directions in the rear ring, collided at two magnetically induced intersection points.