Numerical Study of Advanced Target Design for FIREX-I

In the fast ignition (FI) scheme, at first high-density fuel core plasma is assembled by implosion laser, and it is then heated by peta watt laser to achieve fusion burning condition. A typical target for FI is a shell fitted with a reentrant Au cone to make a pass for heating laser. It is found that a high-Z material such as Au has disadvantage as a cone material in the long-duration and high-intensity laser case by using one-dimensional (1D) PIC, and 1-D relativistic Fokker-Planck (FP) simulations. For FIREX-I scale size experiments, CH has advantages in viewpoint of generation of hot electron and the hot electron transport. Implosion is another important process for FI. Following these results of 1-D PIC and 1-D relativistic FP simulations, 2-D nonspherical implosion dynamics with CD tip is investigated. With sophisticated target and laser pulse shape design, CD tip will be realized without breaking up of cone tip before the maximum density timing, and debasement of implosion performance.