부산대학교 도서관

Simulations are presented of ignition-scale fast ignition targets with the integrated Zuma-Hydra PIC-hydrodynamic capability. We consider a spherical DT fuel assembly with a carbon cone, and an artificially-collimated fast electron source. We study the role of E and B fields and the fast electron energy spectrum. For mono-energetic 1.5MeV fast electrons, without E and B fields, ignition can be achieved with fast electron energy Efig 30 kJ. This is 3.5 the minimal deposited ignition energy of 8.7 kJ for our fuel density of 450 g/cm³. Including E and B fields with the resistive Ohm's law E = nJb gives Efig = 20 kJ, while using the full Ohm's law gives Efig > 40 kJ. This is due to magnetic self-guiding in the former case, and ∇n x ∇T magnetic fields in the latter. Using a realistic, quasi two-temperature energy spectrum derived from PIC laser-plasma simulations increases Efig to (102, 81, 162) kJ for (no E/B, E = nJj, full Ohm's law). f = b Such electrons are too energetic to stop in the optimal hot spot depth. [ABSTRACT FROM AUTHOR]