Subnanosecond high‐voltage breakdown initiated in high‐pressure nitrogen by a runaway electron beam

Abstract

This study reports on subnanosecond breakdowns initiated on high pressure nitrogen by a runaway electron beam in an inhomogeneous electric field. It is shown that a diffuse discharge with a duration of ≥1 ns is formed in the gas diode. Data are reported for the first time on collector measurements of a supershort avalanche electron beam downstream of an anode foil at a nitrogen pressure of 0.5–1.2 MPa. The beam pulsewidth at these pressures is ∼90 ps. At a nitrogen pressure of 1.2 MPa, the number of electrons with an energy >70 keV recorded by the collector is 4 × 10 6 /cm 2 .