The SPEAR3 storage ring at SLAC is once again supplying x-ray beams to users of the Stanford Synchrotron Radiation Laboratory (SSRL). After an accident at SLAC in October, lab director Jonathan Dorfan ordered all experimental facilities shut down pending an investigation and implementation of improved safety procedures (see Physics Today, February 2005, page 24). In mid-January, Dorfan and the Department of Energy approved an SSRL team’s restart plan. Two weeks later, SPEAR3 became the first facility at SLAC to resume operation.
SPEAR3 is a 3-GeV electron storage ring that serves as a synchrotron light source. Unlike the still shutdown B factory storage-ring collider, which gets its beams from SLAC’s 3-km linear accelerator, the standalone SPEAR3 ring can run before the linac resumes operation. “The restart will not divert our attention from the strongest commitment to safety,” says Dorfan.
