The effect of energy stabilization of an ion beam formed by a self-magnetically insulated diode

Abstract

The results of a study of the generation stability of intense pulsed ion beams, which are formed by a self-magnetically insulated diode with an explosive-emission cathode, are presented. Investigations were conducted using a TEMP-4M accelerator configured to operate in the bipolar pulse mode: the first pulse is negative (300–500 ns, 100–150 kV) and the second is positive (150 ns, 200–250 kV). Diodes of different designs were studied: strip focusing diodes, strip planar diodes, and conical focusing diodes. The total beam energy was measured using both the infrared-imaging diagnostics and a conventional calorimeter, while the beam-energy density was measured using the infrared-imaging and acoustic diagnostics. The anode design was modified to improve the ion-beam generation stability. It was obtained that the standard deviation of the total energy and beam-energy density in a pulse train does not exceed 10–11% for an amplitude instability of the ion-current-density pulse of >20–30%. The mechanism of the beam-energy-density stabilization in a pulse train, which is attributed to the ion-charge exchange and formation of accelerated neutrals, is presented. The sources of fluctuations in the total energy and ion-beam-energy density are analyzed. The long service life of ion diodes with self-magnetic insulation and an explosive-emission cathode (>106 pulses) and the high shot-to-shot beam-generation stability make these devices promising for various technological applications.