As a first step in the design of a repetitive pulsed neutron generator, a very small plasma-focus device has been designed and constructed. The system operates at low energy (160 nF capacitor bank, 65 nH, 20–40 kV, and ∼32–128 J). The design of the electrode was assisted by a computer model of Mather plasma focus. A single-frame image converter camera (5 ns exposure) was used to obtain plasma images in the visible range. The umbrellalike current sheath running over the end of the coaxial electrodes and the pinch after the radial collapse can be clearly observed in the photographs. The observations are similar to the results obtained with devices operating at energies several orders of magnitude higher. The calculations indicate that yields of 104–105 neutrons per shot are expected with discharges in deuterium.

Fundamental and applied research on plasmas with high energy density that are unstable and radiate can be done at a relatively low cost with small plasma pinches. In this paper we discuss three experiments using small pinch devices: a capillary discharge, a Z-pinch driven by a small generator, and a low energy plasma focus. The experiments were complemented by magnetohydrodynamics numerical calculations in order to assist the design and physical interpretation of the experimental data. The diagnostics used in the experiments include current and voltage monitors, multipinhole camera, holographic interferometry, and vacuum ultraviolet spectroscopy.

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A gas embedded Z-pinch has been implemented using the SPEED2 generator (4.1 PF equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dta10 13 A/s). Initial conditions to produce a gas embedded z-pinch with enhanced stability by means resistive effects and by finite Larmor radius effects were obtained and electrodes were constructed in order to obtain a double column Z-pinch and a hollow discharge. Experiments were carried out in deuterium at mega amperes currents . Current derivative and voltage signals have been obtained. In addition interferograms have been obatined using a pulse Nd-YAG laser (8ns FWMH at 532nm). Preliminary results on neutron emission were also obtained.