Target designs for electron and ion beam sources with gains > 1

Reduction of input power requirements for laser and charged particle fusion targets has been predicted by implosion calculations that simulate ignition of only a small fraction of the DT fuel instead of the total mass. Once ignition is reached in this localized region, the burn can propagate through the rest of the fuel mass. An approach that achieves this ignition by use of preheat and self-generated magnetic fields is described here, with the result of lower input requirements, i.e., 30 TW and 100 kJ, to achieve breakeven