The Bevatron accelerator at the Lawrence Berkeley Laboratory (LBL), California, as seen encased in its concrete radiation shielding in June 1984. The Bevatron is a proton accelerator which first began operating in 1954, and which produced a number of major discoveries, including the antiproton (1955) and the resonances. Today the Bevatron is primarily used in conjunction with LBL's Heavy Ion linear accelerator (the SuperHilac) as an accelerator of heavy ions. Used in this mode, the pair of accelerators are called the Bevelac.