An alternative geometry for the acceleration of compact toroids

Summary form only given. A parallel-plate-type railgun accelerator employing a slow formation generated compact toroid (CT) and preacceleration compression has been proposed. The perceived advantage of this type of accelerator is that it allows both of the railgun electrodes to be externally supported, thereby allowing a longer acceleration stage as opposed to the present coaxial railgun accelerator where the center conductor must be supported entirely from one end. The efficiency of acceleration is expected to be high, because the fraction of the electrical energy put into the railgun that ends up as kinetic energy of the CT is roughly 1-x/(s+x), where x is the length of the preacceleration compression region and s is the length of the acceleration stage. The slow formation of the CT should yield a cleaner longer-lived CT and allows the formation and acceleration processes to be decoupled. Also the engineering requirements are less stringent in regard to gas valves and electrical systems. The preacceleration compression stage is a necessary artifact of the slow formation; it is, however, useful in its own right as it allows the use of larger-capacitance, lower-voltage capacitors