Advances in the Performance of the SNS Ion Source

R.F. Welton, M.P. Stockli, S.N. Murray, R. Keller
Proceedings of the 2005 Particle Accelerator Conference  
The ion source developed for the Spallation Neutron Source* (SNS) is a radio frequency, multi-cusp source designed to produce ~ 40 mA of Hwith a normalized rms emittance of less than 0.2 π·mm·mrad. To date the source has been utilized in commissioning the SNS accelerator, delivering beams of 10-50 mA with duty-factors of typically ~0.1% for operational periods of several weeks, achieving an availability of ~99%. Ultimately the SNS facility will require beam duty-factors of 6% (1 ms pulse
more » ... (1 ms pulse length, 60 Hz repetition rate, 21 day run-period). Over the last year, several experiments were performed in which the ion source was continuously operated at full duty-factor and maximum beam current on a test stand. Average beam attenuation rates of ~5 mA/day were observed and beams in excess of 30 mA could only be sustained for periods of several hours. Recently, a breakthrough in our understanding of the Cs release process has led to the development of a new source conditioning technique which resulted in a dramatic increase in beam persistence with time. Hbeam attenuation rates have been improved to ~0.4 mA/day, allowing beams in excess of 30 mA to be delivered continuously at full duty factor for periods of ~16 days.
doi:10.1109/pac.2005.1590472 fatcat:fw67pl3egfa7jnoupljygmozsa