SPEAR
SPEAR was a collider at the SLAC National Accelerator Laboratory. It began running in 1972, colliding electrons and positrons with an energy of. During the 1970s, experiments at the accelerator played a key role in particle physics research, including the discovery of the meson, many charmonium states, and the discovery of the tau.
Today, SPEAR is used as a synchrotron radiation source for the Stanford Synchrotron Radiation Lightsource. The latest major upgrade of the ring in that finished in 2004 rendered it the current name SPEAR3.
