The jxB gun

Summary form only given. The jxB gun is a radical modification of the railgun that could, in principle, avoid the velocity limitations of conventional railguns and would be particularly suitable for the acceleration of long, rod-shaped projectiles. The jxB gun may be regarded as a railgun in which the established concepts of augmentation, segmentation, and distributed energy storage are combined and taken to the limit. In the jxB gun a transverse magnetic field B is provided entirely by external coils and an orthogonal current j is provided from rails divided into segments that are much shorter than the length of the projectile, so that, at any time, the projectile is connected to, say, ten segments. Each segment is electrically isolated from its neighbors and is connected to a circuit consisting of a capacitor and an inductor. The circuit is closed by the head of the projectile entering the segment, eliminating the need for separate switches, and the discharge time of the circuit is arranged to be equal to the transit time of the projectile through the segment; this ensures that, except for resistive losses, all of the energy in the capacitor is converted into kinetic energy of the projectile and that the current is zero when the circuit is broken. Since all the capacitors behind the projectile are discharged, the formation of secondary plasma armatures is inhibited.