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Data are presented that are part of a first step in establishing the scientific basis of magnetized target fusion (MTF) as a cost effective approach to fusion energy. A radially converging flux compressor shell with characteristics suitable for MTF is demonstrated to be feasible. The key scientific and engineering question for this experiment is whether the large radial force density required to uniformly pinch this cylindrical shell would do so without buckling or kinking its shape. The time evolution of the shell has been measured with several independent diagnostic methods. The uniformity, height to diameter ratio and radial convergence are all better than required to compress a high density field reversed configuration to fusion relevant temperature and density.

Experiments with coaxial plasma guns at currents in excess of ten megamperes have resulted in the production of high-voltage pulses (0.5 MV) and hard x radiation (10–200 keV). The x-radiation pulse occurs substantially after the high-voltage pulse suggesting that high-energy electrons are generated by dynamic processes in a very high speed (≳106 m/s), magnetized plasma flow. Such flows, which result from acceleration of relatively low-density plasma (10−4 vs 1.0 kg/m3) by magnetic fields of 20–30 T, support high voltages by the back electromotive force-u×B during the opening switch phase of the plasma flow switch. A simple model of classical ion slowing down and subsequent heating of background electrons can explain spectral evidence of 30-keV electron temperatures in fully stripped aluminum plasma formed from plasma flows of 1–2 × 106 m/s. Similar modeling and spectral evidence indicates tungsten ion kinetic energies of 4.5 MeV and 46 keV electron temperatures of a highly stripped tungsten plasma.

The generation of high-energy-density plasmas by the electromagnetic implosion of cylindrical foils (i.e., imploding plasma shells or hollow z-pinches) has been explored analytically and through numerical simulation. These theoretical investigations have been performed for a variety of foil initial conditions (radius, height, and foil mass) for both capacitive and inductive pulsed power systems. The development of the theoretical modeling techniques is presented, covering both circuit models and plasma load models. The circuit models include simple single loop capacitive and multiple loop inductive systems. These circuits are coupled to the imploding plasma loads whose response has been studied by models ranging from simple time varying inductances to complex two-dimensional magnetohydrodynamic numerical simulations. Results from a series of configurations are given, showing the development of modelling techniques used to study the dynamics of the plasma implosion process and the role of instabilities. Interaction between analytic techniques and detailed numerical simulation has led to improvement in all theoretical modeling techniques presently used to study the implosion process. Comparisons of implosion times, shell structure, instability growth rates, and thermalization times have shown good agreement between analytic/heuristic techniques and more detailed two dimensional magnetohydrodynamic simulations. These in turn have provided excellent agreement with experimental results for both capacitor and inductor pulse power systems.