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A study of a 2 kJ, 200 kA, table top plasma focus device as an intense x-ray source is reported. The x-ray yield from a number of gases, (deuterium, nitrogen, neon, argon, and xenon) is measured as a function of filling pressure and in neon as a function of anode length. In gases with Z<18, the plasma implodes to form a uniform cylindrical column, whereas for Z⩾18, the plasma consists of a number of hot spots. A maximum x-ray yield of 16.6 J and pulse length of 10–15 ns was obtained in neon. The x-ray emission was established to be due to H- and He-like line radiation. The temperature estimated from spectroscopic observations was about 300–400 eV at an electron density of (3–5)×1020 cm−3 in neon. At low pressures in neon, hard x-ray radiation, presumably due to electron beams was dominant. Mesh images of different wire materials were recorded at the optimum pressure in neon as a proof of principle for x-ray backlighting.

A short-pulse source based on optical parametric chirped-pulse amplification (OPCPA) technology has been developed with properties that make it a suitable seed for a high-energy OPCPA system. This source generated a diffraction-limited pulse at 910 nm with a full bandwidth of > 165 nm and a spectrum having a transform-limited pulse duration of less than 15 fs. The technique has potential for generating bandwidths > 200 nm and pulse durations < 10 fs.

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A series of experiments on Z-pinch plasmas, driven by a pulsed power generator that delivers 160 kA with a rise time (10%–90%) of 65 ns are reported. Tungsten wires of various diameters were used and results are compared with 15 μm diameter aluminum wire. The expansion of the pinch is studied as a function of wire diameter and material. Schlieren observations show that the coronal plasma of various diameters of tungsten wires expands with the velocity of (9.4±1.0)×103 m/s. The aluminum pinch expands at least a factor of 2 faster. The m=0 perturbations appear at about 8 ns for the aluminum compared with 20 ns for the tungsten pinch. The wavelength and diameter of the perturbations increase with time for both types of wires, and relatively faster for the aluminum pinch. The short wavelength perturbations (∼200 μm) persist for a longer time for larger diameter tungsten wires. Bright spots are seen to appear after 60 ns from the current start for tungsten wires, whereas for aluminum wires, bright spots appear after 40 ns. The decay time of bright spots is 40 ns for the smallest diameter tungsten wire compared with only a few nanoseconds for larger diameter wires. Hard x-ray emission above 6 keV was observed from tungsten wire pinches, but it was not observed from either bright spots or the plasma column for the aluminum pinch. However, hard x-ray emission from the anode due to an electron beam was observed for wires of both materials.