Bubble chamber particle tracks from the particle accelerator at Lawrence Berkeley National Laboratory in California, c. 1960s. This accelerator, Bevatron, began operating in 1954. It was designed to accelerate protons to sufficient energy to create antiprotons, and verify the particle-antiparticle symmetry of nature, then only theorized. The antiproton was discovered there in 1955, resulting in the 1959 Nobel Prize in physics for Emilio Segr癡 and Owen Chamberlain. The Bevatron received a new lease on life in 1971, when it was joined to the SuperHILAC linear accelerator as an injector for heavy ions. The combination was conceived by Albert Ghiorso, who named it the Bevalac. It could accelerate any nuclei in the periodic table to relativistic energies. It was finally decommissioned in 1993.