High-Current Carbon-Epoxy Capillary Cathode

The experimental results of a promising pulsed plasma source, producing electron beams with a current density of up to 10 kA/cm
²
are presented. The beam duration was up to ~1 μs, in an accelerating voltage of up to ~350 kV, without shorting of the cathode-anode gap by the cathode plasma. This plasma electron source is proven to sustain hundreds of pulses without degradation in its emission properties. The cathode plasma electron density n
_e
≤ 10
¹⁵
cm
^-3
, electron T
_e
≤ 13 eV and ion T
_i
≤ 4 eV temperatures, and expansion velocity V
_pl
1.6 × 10
⁶
cm/s were determined using time- and space-resolved spectroscopy and light emission.