Matched impedance, low-voltage vacuum-arc centrifuge

A matched-impedance, low-voltage vacuum-arc centrifuge is described. The centrifuge is a magnetized plasma column, 1 m long, 4 cm in diameter, with ne∼1015 cm−3 and Ti∼3 eV. Rigid rotor frequencies ∼105 rad/s lead to radial, centrifugal separation between isotopes. The source of this rotating plasma column is a vacuum-arc discharge between a negative cathode and a grounded mesh anode at one end of a 2-m-long vacuum chamber. The discharge is driven by an L–C ladder network of 40-mΩ characteristic impedance, which sees the discharge directly as its load, giving a critical damped, flat-topped current pulse of 10-ms duration, with 90% efficient power transfer. An externally applied axial magnetic field, with less than ±1% axial variation, collimates the plasma and induces rotation. Measured cathode erosion rates suggest that such a centrifuge is capable of converting solid into plasma at a rate of 200 mol/day. A piezoelectrically scanned Fabry–Perot interferometer is used to measure ion temperature, Ti, and angular rotation velocity, ω.