Speaker
Description
The U.S. Spallation Neutron Source (SNS) is a state-of-the-art neutron scattering facility delivering the world’s most intense pulsed neutron beams to a wide array of instruments which are used to conduct investigations in many fields of science and engineering. Neutrons are produced by spallation of liquid Hg by bombardment of short (~1s), intense (~40A) pulses of protons delivered at 60 Hz by a storage ring which is fed by a high-intensity, 1 GeV H- LINAC. This facility has operated almost continuously since 2006, with ion source performance increasing steadily over those years, and now currently providing 50-60 mA of H- ions for maintenance-free runs of ~100 days with near 100% availability. Ion source research and development at ORNL has played a key role in enabling and supporting these achievements, and this report provides a snapshot of our current efforts including infrastructure upgrades to the SNS front end systems as well as R&D related to improving the external and internal antenna ion sources. In particular, we have recently simplified and improved the reliability of the plasma ignition system for the external antenna ion source which is discussed in detail. Overall, experimental ion source R&D is conducted on a 65 keV test stand, 2.5 MeV beam test facility, the SNS accelerator during beam study periods, and on a plasma gun test bench. Finally, future directions and collaborations with other laboratories are discussed.
