On possible target design for a heavy ion ignition facility

We investigate minimum energy requirements for ignition of indirect drive targets driven by beams of heavy ions. Two types of hohlraums containing an NIF-scale fusion capsule [J. Lindl, Phys. Plasmas 2 (1995) 3933] are considered. The required ion beam energy is evaluated by combining two and three-dimensional view factor simulations of the radiation transport with one-dimensional hydrodynamic simulations of the converter dynamics. It is found that an ignition facility based on the HIDIF driver concept (I. Hofmann, Nucl. Instr. and Meth. 1998) would require about 4 MJ of the ion beam energy. The impact of the ion-range shortening on target performance is discussed in some detail.