Jefferson Laboratory’s CEBAF accelerator, which was originally designed to provide 4 GeV continuous-wave electron beams, has demonstrated 6 GeV continuous-wave operation. In early August the superconducting radiofrequency (SRF) machine reached 6.07 GeV at a substantial current of 109 mA.
Energies in the 5.65 GeV range had already become routine as a result of incremental improvements since CEBAF began operation in the mid-1990s. Once 6 GeV has become the routine energy level, nuclear physics users will capitalize on it during the coming years, pending the completion of a proposed 12 GeV upgrade, which is to be discussed later this year by the US Nuclear Science Advisory Committee.
The Jefferson Laboratory’s SRF electron-acceleration technology also drives the laboratory’s Infrared Demonstrator Free Electron Laser and is now beginning to see application elsewhere as well. Under a $70 million contract, the laboratory is providing SRF and related cryogenic engineering, assembly and installation support for the Spallation Neutron Source project at Oak Ridge National Laboratory, Tennessee.