KINETIC SIMULATION OF DT IGNITION AND BURN IN ICF TARGETS

Ignition and burn of deuterium-tritium (DT) fuel is investigated for inertial confine- ment fusion (ICF). Collisional kinetic equations describing the interaction of the high energy products of the fusion reactions with the plasma are solved by the particle-in-cell (PIC) method. Results are compared with simpler models, such as local alpha deposition and one-group alpha particle diffusion. Significant differences are found in temperature and density distributions as they evolve during burn. The total fraction of burned fuel is similar for the different models as long as (pR) >> 1 g/cm2 and T 2 10 keV; for (pR) 5 1 g/cm2 and T < 10 keV, however, the kinetic simulation gives considerably lower burn. Uniform as well as spark ignition configurations are simulated for initial temperatures and (pR) values of practical interest and for fuel masses between 0.1 and 10 mg. In addition, optically thick configurations igniting at temperatures below 5 keV are considered.