Published online by Cambridge University Press: 09 March 2009
Experimental results are reported on an extractor for pulsed, high-intensity beams of intermediate mass ions. Aluminum and indium plasmas were generated using a metal vapor vacuum arc. A method for electrostatic separation of ions from electrons at the anode was utilized to generate constant current beams, insensitive to plasma flux variations.
A maximum extraction voltage of 30 kV was applied across a 1·6 cm gap. Voltage pulse length ranged from 10 to 50μsec. Peak current densities of 15 mA/cm2 and normalized emittance of εn<3χ10-7; π-m-rad were achieved for Al+ and In+ from a 20-cm2 anode. Ions were predominantly in the +1 ionization state with no observable species contamination. The technology may have application to the induction linac approach to Accelerator Inertial Fusion.