Laser-Driven Super-High Velocity Targets for Impact Fast Ignition

In Impact Fast Ignition\footnote{M. Murakami et al., Nucl. Instrum. Meth. Phys. Res. A \textbf{544}, 67 (2005).} (IFI), a compressed main fuel is ignited by impact collision of a fragment of separately imploded fuel (impactor). A most critical requirement for the IFI is to achieve a super-high velocity (1000 km/s) of the impactor to form an igniting hot spot by converting the imploding kinetic energy into its own thermal energy. One then needs to substantially suppress Rayleigh-Taylor (RT) instability for a stable acceleration of the target. The super-high velocity is achieved by utilizing such a suppression technique of RT instability as double ablation in high-Z doped targets.\footnote{S. Fujioka et al., Phys. Rev. Lett. \textbf{92}, 195001 (2004).} We will present the experimental results of the laser-driven planar targets for the IFI.