Study of an electron-beam discharge into a vacuum diode with polyethylene anode

Abstract

A 40‐nsec‐duration 2.5‐MV 25‐kA electron‐beam discharge into a vacuum diode with polyethylene anode has been studied with time‐resolved optical photography and soft x‐ray diagnostics. The beam was observed to be initially uniform but to filament at 15 nsec and form a single powerful pinch at 25 nsec. The interaction of the pinched beam and the anode produces a plasma ≤ 75 μm in diameter with a temperature of ∼ 50 eV. Neutron and deuteron emission from the diode were observed and the intensity ratios are consistent with a beam target neutron production mechanism.