Experimental study on the generation and transmission of the high-current repetitive electron beam

When vacuum electron diode is repetitively operated, it presents some peculiar characteristics. Because of its small screening radius and short delay time, graphite is chosen as the cathode material. In experiments, the following results were attained: (1) when the annular cathode is thinned or the repetitive rate is increased, because of thermal effect of current and quickening expanding speed of plasma, the consistency of pulses in a burst is worsened; (2) with the strength of guiding magnetic field increased, the plasma is more restricted and expand slower, and the total current, as well as the electron-emitting area is reduced and the impendence of diode is increased. At last, when the strength of guiding magnetic field is 1.5 T and the cathode is 1 mm thick, a uniform electron beam of