Performance of the Magnetron H~- Source on the BNL 200 MeV Linac

摘要

A magnetron surface plasma H~- ion source has been used at Brookhaven since 1982 for injection into the 200 MeV linac. Since 1989, this source has operated with a circular aperture, injecting into an RFQ. The source typically produces 90-100 mA of H~- at 35 keV, in 700 μs pulses at up to 10 Hz. The arc parameters are ～15 A, 150 V, and the extracted e/H- ratio is 1/2. Ions are extracted from a 2.8 mm diameter aperture (J = 1.6 A/cm~2). The emittance is approximately ε_(n,ms) = 0.4 π mm mrad. The performance is very reliable, operating continuously for ～6 months, with essentially no parameter adjustments required once the source is stabilized.