Targets for Electron-Beam Fusion

I have performed computer simulations of high-density, spherical shells containing DT gas, irradiated by pulsed electron beams. For these targets, (1) the optimal shells are thick enough that few electrons reach their inner surface, (2) the low-level bremsstrahlung which penetrates the shell significantly affects the target performance, (3) breakeven requires about ${10}^{15}$ W deposited for 5 nsec. This represents a considerable improvement over the behavior of bare DT spheres; further improvements may reduce the power to ${10}^{14}$ W.