What has JLab done with SRF?

Built and operated CEBAF...

 

When the Continuous Electron Beam Accelerator Facility (CEBAF) project began in the mid-1980s at what came to be called the Thomas Jefferson National Accelerator Facility (Jefferson Lab), there was an immediate need to gear up to meet challenges for implementing the then-novel SRF technology on which CEBAF was to be based. That gearing up involved a number of scientific and technological activities that have evolved and that continue in Newport News and elsewhere today.

CEBAF was built to serve nuclear physics experimenters by giving them high-quality, continuous wave (CW) beams of electrons for probing the quark and gluon structure of nuclear matter. The beams reach energies of up to 6 GeV (billion electron volts). They come from CEBAF’s 7/8-mile, racetrack-shaped underground accelerator in which each “straightaway” contains an SRF linear accelerator, or linac. In the beginning, CEBAF represented an order-of-magnitude increase in the scale of SRF accelerators, and today remains the world’s largest operating application of SRF.

In fact, CEBAF was the first large-scale application of SRF anywhere. To apply SRF at that scale, the challenges were technological, industrial, and in some cases scientific. SRF was a newly developed technology, and reliable SRF components needed to be manufactured, processed, assembled, tested, and installed on a production basis. In some cases, subcomponents had to be researched and developed.

As a result, Jefferson Lab’s SRF R&D capabilities were born, together with some purpose-built production capabilities targeted on the task of building CEBAF. These SRF capabilities were based in large part on the importation of people from the successful SRF R&D programs at Cornell University and Stanford. The test lab—a high-bay facility inherited from NASA by Jefferson Lab—was converted largely to SRF purposes.

For a decade as of 2005, CEBAF has been reliably serving nuclear and particle physics experimenters with SRF-accelerated beams of electrons having outstanding characteristics. Because CEBAF’s scientific successes have led directly to a new generation of questions about the quark structure of nuclei, and because CEBAF itself has performed so well, an upgrade that will double CEBAF’s energy is a near-term component of the U.S. Department of Energy Office of Science’s road map, Facilities for the Future of Science: A Twenty Year Outlook