New ion source nears completion

Work on NSCL's next-generation ion source reached a major milestone Thursday with the ignition of plasma. The successful test puts project a hair's-breadth away from its ultimate goal – increasing the availability of rare isotopes for study by experimenters at the laboratory.

“Now we know that this more than just a magnet; it is actually working,” said NSCL ion source group leader Peter Zavodsky. “It's a matter of a few weeks when the complete safety system will be in place and we can put high voltage in and actually extract ions.”

The new device goes by the name SuSI, short for Superconducting Source for Ions. Like NSCL's two existing ion sources, the Superconducting ECR (SC-ECR) and the Advanced Room Temperature Ion Source (ARTEMIS), SuSI in effect will be the headwaters of the ion stream that passes through the cyclotrons and down the beam line to various experimental devices. SuSI, however, will produce beams at significantly higher intensity and brilliance.

SuSI continues NSCL's long tradition of innovation related to particle beams. The day SC-ECR was turned on in the early 1990s, NSCL became the first laboratory in the world with a superconducting ion source. Since then, similar advanced ion sources have come online at laboratories in North America, Europe and Asia, often with significant help from outside contractors. NSCL, in contrast, opted to do almost all of the work on SuSI in-house.

“Everything, from design to coil winding, was done here,” said Zavodsky. “We just felt like we had most of the expertise we needed.”

The telltale faint blue glow of ionized plasma during Thursday's test run suggests Zavodsky is correct.

The three-year SuSI project is supported in part by the National Science Foundation. Portions of the design were adopted from work done at Lawrence Berkeley National Laboratory.