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Magnetized target fusion (MTF) is a means to compress plasmas to fusion conditions that uses magnetic fields to greatly reduce electron thermal conduction, thereby greatly reducing compression power density requirements. The compression is achieved by imploding the boundary, a metal shell. This effort pursues formation of the field-reversed configuration (FRC) type of magnetized plasma, and implosion of the metal shell by means of magnetic pressure from a high current flowing through the shell. We reported previously on experiments demonstrating that we can use magnetic pressure from high current capacitor discharges to implode long cylindrical metal shells (liners) with size, symmetry, implosion velocity, and overall performance suitable for compression of FRCs. We also presented considerations of using deformable liner-electrode contacts of Z-pinch geometry liners or theta pinch-driven liners, in order to have axial access to inject FRCs and to have axial diagnostic access. Since then, we have experimentally implemented the Z-pinch discharge driven deformable liner-electrode contact, obtained full axial coverage radiography of such a liner implosion, and obtained 2 112 dimensional MHD simulations for a variety of profiled thickness long cylindrical liners. The radiographic results indicate that at least 16 times radial compression of the inner surface of a 0.11-cm-thick AI liner was achieved, with a symmetric implosion, free of instability growth in the plane of the symmetry axis. We have also made progress in combining 21/2-D MHD simulations of FRC formation with imploding liner compression of FRCs. These indicate that capture of the injected FRC by the imploding liner can be achieved with suitable relative timing of the FRC formation and liner implosion discharges. Index Terms--Field-reversed configuration, liner implosion, magnetized plasma compression, magnetized target fusion.

Field reversed theta pinch technology is employed with programmed cusp fields at the theta coil ends to form high-density field-reversed configuration (FRC) plasmas. The well-formed FRC plasmas have volume-averaged density of 2 - 4 X [10.sup.22] [m.sup.-3], total temperature ([T.sub.e] + [T.sub.i]) of 300-500 eV, and plasma lifetime between 10-20 [micro]s in 50-70 mtorr of deuterium static gas fill. The achieved FRC parameters are very close to the desired target plasma requirements for magnetized target fusion. Index Terms--Field-reversed configuration, fusion reactors, magnetized target fusion, plasma confinement, plasma generation, plasma measurements, plasma pinch, plasmas.

The design and first successful demonstration of an imploding solid liner with height to diameter ratio, radial convergence, and uniformity suitable for compressing a field reversed configuration is discussed. Radiographs indicated a very symmetric implosion with no instability growth, with ~13x radial compression of the inner liner surface prior to impacting a central measurement unit. The implosion kinetic energy was 1.5 megajoules, 34% of the capacitor stored energy of 4.4 megajoules. Index Terms--Capacitor bank, field reversed configuration, FRC, implosion, magnetized target fusion, megamp, MTF, radiography, solid liner.

Field reversed theta pinch technology is employed with programmed cusp fields at the theta coil ends to form high-density field-reversed configuration (FRC) plasmas. The well-formed FRC plasmas have volume-averaged density of 2 – 4 × 1022 m-3, total temperature (Te + Ti) of 300–500 eV, and plasma lifetime between 10–20 μs in 50–70 mtorr of deuterium static gas fill. The achieved FRC parameters are very close to the desired target plasma requirements for magnetized target fusion. [ABSTRACT FROM AUTHOR]