In the last few years, high power lasers have demonstrated the possibility to explore a new state of matter, the so-called warm dense matter. Among the possible techniques utilized to generate this state, we present the dynamic compression technique using high power lasers. Applications to planetary cores material (iron) will be discussed. Finally new diagnostics such as proton and hard-x-ray radiography of a shock propagating in a solid target will be presented.

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We measure the conversion efficiency of 351 nm laser light to soft x-rays (0.1-5 keV) for Au, U and high Z mixtures "cocktails" used for hohlraum wall materials in indirect drive ICF. We use spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates to achieve constant and uniform laser intensities of 10 14 and 10 15 W/cm 2 over the target surface that are relevant for the future ignition experiments on NIF. The absolute time and spectrally-resolved radiation flux is measured with a multichannel soft x-ray power diagnostic. The conversion efficiency is then calculated by dividing the measured x-ray power by the incident laser power from which the measured laser backscattering losses is subtracted. After ~0.5 ns, the time resolved x-ray conversion efficiency reaches a slowly increasing plateau of 95% at 10 14 W/cm 2 laser intensity and of 80% at 10 15 W/cm 2 . The M-band flux (2-5 keV) is negligible at 10 14 W/cm 2 reaching ~1% of the total x-ray flux for all target materials. In contrast, the Mband flux is significant and depends on the target material at 10 15 W/cm 2 laser intensity, reaching values between 10% of the total flux for U and 27% for Au. Our LASNEX simulations show good agreement in conversion efficiency and radiated spectra with data when using XSN atomic physics model and a flux limiter of 0.15, but they underestimate the generated M-band flux. I IntroductionIn indirect drive inertial confinement fusion (ICF) experiments, intense laser or charged particle beams heat the interior of high-Z cylindrical cavities called hohlraums to efficiently generate soft x-rays. The role of the soft x-rays is to uniformly produce an ablation drive that compresses the DT filled capsule placed inside the hohlraum, driving it to ignition and burn [1]. Due to the relaxed requirements on laser-beam uniformity and reduced sensitivity to hydrodynamic instabilities the indirect drive scenario is the main approach for future ignition experiments at the National Ignition Facility (NIF) [2,3,4]. In such a hohlraum containing a capsule and heated by laser beams the power balance is given by [5,6]:η CE (P laser -P backscatter ) = P walls +P LEH + P capsule =σT R 4 [(1-α)A wall +A LEH +f capsule A capsule ] (1) where η CE is the laser conversion efficiency into soft x-rays (<2 keV), P laser is the incident laser power, P backscatter is the backscattered light by parametric laser-plasma instabilities, P capsule is the radiation absorbed by the capsule, P LEH is the radiation escaping through the hohlraum laser entrance holes (LEH) and P walls is the radiation loss in the hohlraum walls.Furthermore, σ is the Stefan-Boltzmann constant, T R is the hohlraum radiation temperature (≤300 eV), α is the x-ray albedo of the hohlraum wall [7], defined as the ratio between the re-emitted and incident soft x-ray flux at the hohlraum wall, A wall and A LEH are the areas of the hohlraum wall and LEH's, f capsule is the fraction of incident x-ray flux that is absorbed by the capsule and A ...

Measurement of the shock-heated melt curve of lead using pyrometry and reflectometry