Abstract
The use of plasma emission cathode in the conjunction with a multiple apertured electron optical system (EOS) is promising for the multi-MW class electron beams of a large cross-sectional area. In a multi-aperture source, the beam parameters could be raised simply due to increase of the number of apertures (i.e. an effective emission area), if a uniformity of the electron emission over a large-area plasma cathode is ensured. In the presented paper, the cross-sectional distribution of the emission current density was investigated using the X-ray diagnostic technique for two versions of the diode-type EOS, with electrodes performed as flat molybdenum "grids". The first one had 241 apertures arranged hexagonally inside a circle with a diameter of 8.3 cm and the second had 499 apertures within a circle of 11.8cm diameter. The emission plasma is produced using a single arc-discharge plasma generator placed on the axis at 20 cm from the EOS. It was demonstrated that multi-aperture systems with a single on-axis plasma generator can be effectively employed to obtain large-area beams, even in the presence of the guiding magnetic field. All apertures are emitting in the 499-apertured EOS. The beam current density is quite uniform up to the radius 2.5cm and gradually decreases to the periphery.
Original language | English |
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Article number | 012032 |
Number of pages | 6 |
Journal | Journal of Physics: Conference Series |
Volume | 830 |
Issue number | 1 |
DOIs | |
Publication status | Published - 4 May 2017 |