Fig. 1. 2D schematic view of simulated structure.

Fig. 2. At cathode voltage −10 kV and gas pressure 30 Pa: (a) potential distribution at 11 ns, (b) seed electrons (green) and new electrons (blue) distribution at 11 ns, (c) potential distribution at 15 ns, and (d) seed electrons (green) and new electrons (blue) distribution at 15 ns.

Fig. 3. Time-dependent properties of PS-sourced electron beam, showing (a) waveform of discharge current and beam current, (b) time-dependent axial mean velocity of electrons, (c) time-dependent radial mean velocity of electrons, and (d) electron beam velocity distributions at different moments.

Fig. 4. Axial velocity-dependent electron density distributions of electron beam at (a) different gas pressures, (b) different cathode voltages, and (c) different cathode aperture sizes.