Effect of Auto–focusing of the Electron Beam in the Relativistic Vacuum Diode
نویسنده
چکیده
A hypothesis of the beam auto–focusing in the relativistic vacuum diode with a needle anode is proposed. A physical model of the effect is elaborated. As is shown, auto –focusing of high current beam can be caused by ions emitting from the anode. Initial (pre focusing) stage of focusing is provided with ionization of the gas molecules absorbed in the anode surface. Then (at quasi–steady stage), the focusing is driven by the metal ions being evaporated from the anode heated by the beam. Simulation of the process shown the duration of initial pre focusing stage would be within 0.1–0.2 nsec.
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