Abstract
A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). The feedback system configuration, setup procedures, and optimization of performance are described. Results of several experimental tests of system performance are presented including observations of instability threshold improvement and grow-damp experiments, which yield estimates of instability growth and damping rates. A major effort was undertaken to identify and study several factors limiting system performance. Evidence obtained from these tests suggests that performance of the prototype was limited by higher instability growth rates arising from beam leakage into the gap at lower RF buncher voltage and the onset of instability in the horizontal plane, which had no feedback.
| Original language | English |
|---|---|
| Article number | 124904 |
| Journal | Journal of Applied Physics |
| Volume | 102 |
| Issue number | 12 |
| DOIs | |
| State | Published - 2007 |
Funding
The LANL work up through 1 June 2006 was supported by the U.S. Department of Energy under Contract No. W-7405-ENG-36 (with the University of California) and after 1 June 2006 under Contract No. DE-AC52-06NA25396 (with the Los Alamos National Security, LLC). ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. The LBNL work was supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The Indiana University group is supported by grants from the U.S. Department of Energy under Contract No. DE-FG0292ER40747 and the National Science Foundation Grant No. NSF PHY-0552389.