A 100 MW electron source with extremely high beam area compression

100 MW electron gun for a 34.3 GHz magnicon

“…Experience with guns for the 7 GHz magnicon [5] (having a measured beam area compression of 2300:1), and for the 11.4 GHz magnicon [11] (having a compression of about 1500:1), shows that even if the gun is fabricated with unintended inaccuracy [11], and even if it's perveance differs from the design value as much as 10-15%, that the measured beam diameter still exceeds the Brillouin limit by no more than 40%.…”

“…1 and Ref. 2), two stage compression is used [4], as proven for the 7 GHz magnicon [5], and for the 11.4 GHz magnicon [6]. Compression in this gun is only partially electrostatic (500:1), since more than this would lead to a higher electric field at the focus electrode; and would require a magnetic field of about 13 kG at the edge of the pole piece, leading to saturation in the iron [4].…”

High-power high-convergence electron gun for an 11.424-ghz pulsed magnicon

“…In order to achieve the required area compression ratio, a simple scheme described in [5] was used, which allowed the minimum number of stages during beam formation. This scheme contains: 1) a Pierce diode gun with a cathode shielded from the magnetic field and 2) a solenoid with a beam transmission hole in the entrance pole piece.…”

34 GHz, 45 MW pulsed magnicon for accelerator applications

“…In experimental tests also at Budker INP [4], a second harmonic magnicon amplifier operating at 7.0 GHz achieved an output power of 55 MW in a 1.1 psec pulse and a repetition rate of 3 Hz, with a gain of 72 dB and efficiency of 56%. This device is driven at 3.5 GHz and uses 430 kV, 230 A beam with an area compression ratio of about 2300:l [5].…”