Low-adiabat implosions for fast-ignition inertial confinement fusion

A method to assemble thermonuclear fuel for fast ignition with high densities, high ρR, and a small size hot spot is presented. Massive cryogenic shells can be imploded with a low implosion velocity Vl on a low adiabat α using the relaxation-pulse technique. While the low Vl yields a small hot spot, the low α leads to large peak values of the density and areal density. It is shown that a 750-kJ laser can assemble fuel with Vl - 1.7*107 cm/s; α - 0.7; ρ - 400 g/cc; ρR - 3 g/cm2; and hot-spot volume less than 10% of the compressed core. If ignited, this fuel assembly can produce yields up to 5*1019 of interest in inertial fusion applications. (authors)