KINETIC SIMULATION OF DT IGNITION AND BURN IN ICF TARGETS

Ignition and burn of deuterium-tritium (DT) fuel is investigated for i nertial confinement fusion (ICF). Collisional kinetic equations descri bing the interaction of the high energy products of the fusion reactio ns with the plasma are solved by the particle-in-cell (PIC) method. Re sults are compared with simpler models, such as local alpha deposition and one-group alpha particle diffusion. Significant differences are f ound in temperature and density distributions as they evolve during bu rn. The total fraction of burned fuel is similar for the different mod els as long as [rho R] >> 1 g/cm(2) and T greater than or equal to 10 keV: for [rho R] less than or equal to 1 g/cm(2) and T < 10 keV, howev er, the kinetic simulation gives considerably lower burn. Uniform as w ell as spark ignition configurations are simulated for initial tempera tures and [rho R] values of practical interest and for fuel masses bet ween 0.1 and 10 mg. In addition, optically thick configurations igniti ng at temperatures below 5 keV are considered.