Nuclear Diagnostics of ICF
In inertial confinement fusion (ICF), a high temperature and high density plasma is produced by the spherical implosion of a small capsule1. A spherical target capsule is irradiated uniformly by a laser beam (direct irradiation) or x-rays from a high Z enclosure (hohlraum) that is irradiated by laser or ion beams (indirect irradiation). Then high- pressure ablation of the surface causes the fuel to be accelerated inward. Thermonuclear fusion reactions begin in the center region of the capsule as it is heated to sufficient temperature (10 keV) by the converging shocks (hot spot formation). During the stagnation of the imploded shell, the fuel in the shell region is compressed to high density (∼103 times solid density in fuel region). When these conditions are established, energy released by the initial nuclear reactions in center “hot-spot” region can heat up the cold “fuel” region and cause ignition.
KeywordsAreal Density Inertial Confinement Fusion Neutron Imaging Secondary Neutron National Ignition Facility
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