Three years of reassembly and approximately $13 million later, Lawrence Livermore National Laboratory's prototype Beamlet laser for its National Ignition Facility in Livermore, Calif., is back at work at Sandia National Laboratories in Albuquerque, N.M., monitoring inertial confinement fusion experiments on the Z accelerator x-ray source. In recent tests, the renamed Z-Beamlet confirmed that Z uniformly compressed a simulated fusion pellet.The megajoule-class laser (shown with technician displaying a debris shield) strikes a metal plate in the target chamber, producing x-rays that image the imploding pellet during a shot. Previously, researchers at the facility relied on data from Z itself that indicated how efficiently it generated its 1.9-MJ x-ray pulses.