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Extreme ultraviolet radiation from a high harmonic source has been used to measure the free-free attenuation coefficient and real refractive index of warm dense aluminium, with sample conditions of near solid density and temperature of 0.9 ± 0.23 eV. These were compared to results from the literature, where the measured attenuation coefficients showed some consistency with the modelling and existing data from a previous experiment. The absolute values of the attenuation coefficient were found to reside between the different sets of models for the warm dense matter (WDM) attenuation coefficient, and were found to be more in line with modelling and measurements of the cold opacity from the literature. Novel measurements of the real refractive index of WDM were also achieved—while ambiguity makes these measurements consistent with all the models, they prove useful as a proof-of-concept for future WDM studies.

The propagation of fast electron currents in near solid-density media was investigated via proton probing. Fast currents were generated inside dielectric foams via irradiation with a short ($\ensuremath{\sim}0.6\text{ }\text{ }\mathrm{ps}$) laser pulse focused at relativistic intensities ($I{\ensuremath{\lambda}}^{2}\ensuremath{\sim}4\ifmmode\times\else\texttimes\fi{}{10}^{19}\text{ }\text{ }\mathrm{W}\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }\ensuremath{\mu}{\mathrm{m}}^{2}$). Proton probing provided a spatially and temporally resolved characterization of the evolution of the electromagnetic fields and of the associated net currents directly inside the target. The progressive growth of beam filamentation was temporally resolved and information on the divergence of the fast electron beam was obtained. Hybrid simulations of electron propagation in dense media indicate that resistive effects provide a major contribution to field generation and explain well the topology, magnitude, and temporal growth of the fields observed in the experiment. Estimations of the growth rates for different types of instabilities pinpoints the resistive instability as the most likely dominant mechanism of beam filamentation.

A magneto-optic probe was used to make time-resolved measurements of the magnetic field in both a single supersonic jet and in a collision between two supersonic turbulent jets, with an electron density ⇡ 1018 cm3 and electron temperature ⇡ 4 eV. The magneto-optic data indicated the magnetic field reaches B ⇡ 200 G. The measured values are compared against those obtained with a magnetic induction probe. Good agreement of the time-dependent magnetic field measured using the two techniques is found.

The bremsstrahlung x-rays from a laser-solid interaction have been investigated for the use of radiography. The scaling of the x-rays as a function of energy has been characterized and modelled and agrees with previous measurements.

We report on the experimental observation of the instability of a plasma shell, which formed during the expansion of a laser-ablated plasma into a rarefied ambient medium. By means of a proton radiography technique, the evolution of the instability is temporally and spatially resolved on a timescale much shorter than the hydrodynamic one. The density of the thin shell exceeds that of the surrounding plasma, which lets electrons diffuse outward. An ambipolar electric field grows on both sides of the thin shell that is antiparallel to the density gradient. Ripples in the thin shell result in a spatially varying balance between the thermal pressure force mediated by this field and the ram pressure force that is exerted on it by the inflowing plasma. This mismatch amplifies the ripples by the same mechanism that drives the hydrodynamic nonlinear thin-shell instability (NTSI). Our results thus constitute the first experimental verification that the NTSI can develop in colliding flows. Funding agencies: EPSRC [EP/I031766/1, EP/K022415/1, EP/I029206/1, SFB-TR18, GRK1203, ENE2013-45661-C2-1-P, PEII-2014-008-P]; Vetenskapsradet [Dnr 2010-4063]; Triangle de la Physique RTRA network (ULIMAC)

Experiments where a laser-generated proton beam is used to probe the megagauss strength self-generated magnetic fields from a nanosecond laser interaction with an aluminum target are presented. At intensities of 1015 Wcm(-2) and under conditions of significant fast electron production and strong heat fluxes, the electron mean-free-path is long compared with the temperature gradient scale length and hence nonlocal transport is important for the dynamics of the magnetic field in the plasma. The hot electron flux transports self-generated magnetic fields away from the focal region through the Nernst effect [A. Nishiguchi et al., Phys. Rev. Lett. 53, 262 (1984)] at significantly higher velocities than the fluid velocity. Two-dimensional implicit Vlasov-Fokker-Planck modeling shows that the Nernst effect allows advection and self-generation transports magnetic fields at significantly faster than the ion fluid velocity, v(N)/C(s) approximate to 10.

A laser generated proton beam was used to measure the megagauss strength self-generated magnetic fields from a nanosecond laser interaction with an aluminum target. At intensities of 10 15 W cm -2, the significant hot electron production and strong heat fluxes result in non-local transport becoming important to describe the magnetic field dynamics. Two-dimensional implicit Vlasov-Fokker-Planck modeling shows that fast advection of the magnetic field from the focal region occurs via the Nernst effect at significantly higher velocities than the sound speed, v N/c s ≈ 10. © 2011 IOP Publishing Ltd.

Protons accelerated by a picosecond laser pulse have been used to radiograph a 500μm diameter capsule, imploded with 300 J of laser light in 6 symmetrically incident beams of wavelength 1.054μm and pulse length 1 ns. Point projection proton backlighting was used to characterize the density gradients at discrete times through the implosion. Asymmetries were diagnosed both during the early and stagnation stages of the implosion. Comparison with analytic scattering theory and simple Monte Carlo simulations were consistent with a 3±1g/cm3 core with diameter 85±10μm. Scaling simulations show that protons >50MeV are required to diagnose asymmetry in ignition scale conditions. © 2006 The American Physical Society.

The proton radiography technique has been used to investigate the incidence of a 3 ×1019 W/cm2 infrared pulse with a 125 μm-diameter gold wire. The laser interaction is observed to drive the growth of a radial electric field ∼ 1010 V/m on the surface of the wire which rises and decays over a temporal window of 20 ps. Such studies of the ultrafast charging of a solid irradiated at high-intensity may be of relevance to schemes for laser-driven ion acceleration and the fast-ignitor concept for inertial confinement fusion.

The use of laser-accelerated protons as a particle probe for the detection of electric fields in plasmas has led in recent years to a wealth of novel information regarding the ultrafast plasma dynamics following high intensity laser-matter interactions. The high spatial quality and short duration of these beams have been essential to this purpose. We will discuss some of the most recent results obtained with this diagnostic at the Rutherford Appleton Laboratory (UK) and at LULI - Ecole Polytechnique (France), also applied to conditions of interest to conventional Inertial Confinement Fusion. In particular, the technique has been used to measure electric fields responsible for proton acceleration from solid targets irradiated with ps pulses, magnetic fields formed by ns pulse irradiation of solid targets, and electric fields associated with the ponderomotive channelling of ps laser pulses in under-dense plasmas.

Presented are the results of experiments in which jets are created through the collision of two laser-produced plasmas. These experiments use a simple "v-foil" target design: two thin foils are placed at an angle of 140° to each other and irradiated with a high-energy laser. The plasmas from the rear face of these foils collide and drive plasma jets moving with a velocity of ~300 km s−1. By carefully choosing the foil thickness and material to suit the laser conditions available, it has proven possible to create plasma jets for which the relevant scaling parameters show significant overlap with those of outflows associated with young stellar objects (YSOs). Preliminary results are also shown from experiments to study the effect of an ambient gas on jet propagation. Nominally identical experiments are conducted either in vacuum or in an ambient medium of 5 mbar of nitrogen gas. The gas is seen to increase the jet collimation and to introduce shock structures at the head of the outflow.

We review the potential of x-ray scattering as a dense plasma diagnostic and present data taken from experiments in which x-ray scattering from dense plasmas is developed as a diagnostic tool. In one type of experiment the scattered photons are detected as a function of angle using direct detection onto a CCD chip. Such experiments are designed primarily to observe the static ion–ion structure factor, which is expected to dominate the scattering for moderate to high Z plasmas at a few electronvolts temperature. In a second type of experiment we have used a curved crystal to observe spectrally resolved x-ray scattering at a fixed angle. This experiment was designed to observe the dynamical structure factor of the plasma.

High power lasers are a tool that can be used to determine important parameters in the context of Warm Dense Matter, i.e. at the convergence of low-temperature plasma physics and finite-temperature condensed matter physics. Recent results concerning planet inner core materials such as water and iron are presented. We determined the equation of state, temperature and index of refraction of water for pressures up to 7 Mbar. The release state of iron in a LiF window allowed us to investigate the melting temperature near the inner core boundary conditions. Finally, the first application of proton radiography to the study of shocked material is also discussed.

A forwardly-peaked bright neutron source was produced using a laser-driven, deuteron-rich ion beam in a pitcher-catcher scenario. A proton-free ion source was produced via target normal sheath acceleration from Au foils having a thin layer of D_2 O ice at the rear side, irradiated by sub-petawatt laser pulses (∼200 J, ∼750 fs) at peak intensity 2 x 10^20 Wcm^-2. The neutrons were preferentially produced in a beam of ∼70° FWHM cone along the ion beam forward direction, with maximum energy up to ∼40 MeV and a peak flux along the axis 2 x 10^9 n/sr for neutron energy above 2.5 MeV. The experimental data is in good agreement with the simulations carried out for the d(d,n)He reaction using the deuteron beam produced by the ice-layered target.

This work was supported in part by DTRA under Basic Research Award No. HDTRA1-10-10077. Here, we show that defocusing of the laser in the interaction of a picosecond duration, 1.053 μm wavelength, high energy pulse with a cone-wire target does not significantly affect the laser energy coupling efficiency, but does result in a drop in the fast electron effective temperature. This may be beneficial for fast ignition, since not only were more electrons with lower energies seen in the experiment but also the lower prepulse intensity will reduce the amount of preplasma present on arrival of the main pulse, reducing the distance the hot electrons have to travel. We used the Vulcan Petawatt Laser at the Rutherford Appleton Laboratory and gold cone targets with approximately 1 mm long, 40 μm diameter copper wires attached to their tip. Diagnostics included a quartz crystal imager, a pair of highly oriented pyrolytic graphite crystal spectrometers and a calibrated CCD operating in the single photon counting regime, all of which looked at the copper Kα emission from the wire. A short pulse optical probe, delayed 400 ps relative to the main pulse was employed to diagnose the extent of plasma expansion around the wire. A ray-tracing code modeled the change in intensity on the interior surface of the cone with laser defocusing. Using a model for the wire copper Kα emission coupled to a hybrid Vlasov-Fokker-Planck code, we ran a series of simulations, holding the total energy in electrons constant whilst varying the electron temperature, which support the experimental conclusions. Publisher PDF

We report on the temporally and spatially resolved detection of the precursory stages that lead to the formation of an unmagnetized, supercritical collision-less shock in a laser-driven laboratory experiment. The measured evolution of the electrostatic potential associated with the shock unveils the transition from a current free double layer into a symmetric shock structure, stabilized by ion reflection at the shock front. Supported by a matching Particle-In-Cell simulation and theoretical considerations, we suggest that this process is analogeous to ion reflection at supercritical collisionless shocks in supernova remnants., 5 pages, 4 figures, accepted for publication in Physical Review Letters

Summary form only given. Collisionless shocks are relevant to a variety of astrophysical scenarios, such as the generation of highly energetic particles and cosmic rays during supernova explosions, and have recently been the focus of several laboratory plasma investigations employing high-power lasers. We present here a study of the generation and evolution of collisionless shocks in tenuous plasma, carried out at the VULCAN laser facility, Rutherford Appleton Laboratory. The shocks are generated during the expansion of a warm plasma, produced after the irradiation of a thin solid foil by a long (∼1ns) and intense (∼1015 W/cm2) laser pulse, into a tenuous (∼ 1016 cm−3), non magnetized background plasma. Shock structures are seen to develop at the interface between the two plasmas. The shocks are probed via a proton projection imaging (PPI) technique [1], which allows one to measure the electric field distribution at the shock front with high spatial resolution (∼ µm), and temporally resolve its propagation within a ps scale. The temporal evolution of electrostatic shocks in ambient plasma has been observed and the associated electric field has been reconstructed in a number of different conditions. In particular, we have identified in the data the transition from an unipolar field profile, typical of a double layer structure, into a bipolar electric field, and the subsequent formation of a collisionless, electrostatic shock. This structure is then seen to propagate in the ambient plasma with a Mach number ∼3.5. A PIC simulation supports the existence of high Mach number (∼3.3) shocks launched by collision of plasma clouds of equal electron and ion temperatures [2].

The development of current instabilities behind the front of a cylindrically expanding plasma has been investigated experimentally via proton probing techniques. A multitude of tubelike filamentary structures is observed to form behind the front of a plasma created by irradiating solid-density wire targets with a high-intensity (I~10 19 W/cm²), picosecond-duration laser pulse. These filaments exhibit a remarkable degree of stability, persisting for several tens of picoseconds, and appear to be magnetized over a filament length corresponding to several filament radii. Particle-in-cell simulations indicate that their formation can be attributed to a Weibel instability driven by a thermal anisotropy of the electron population. We suggest that these results may have implications in astrophysical scenarios, particularly concerning the problem of the generation of strong, spatially extended and sustained magnetic fields in astrophysical jets. Refereed/Peer-reviewed

In this paper we report on the radiography of a shock-compressed target using laser produced proton beams. A low-density carbon foam target was shock compressed by long pulse high-energy laser beams. The shock front was transversally probed with a proton beam produced in the interaction of a high intensity laser beam with a gold foil. We show that from radiography data, the density profile in the shocked target can be deduced using Monte Carlo simulations. By changing the delay between long and short pulse beams, we could probe different plasma conditions and structures, demonstrating that the details of the steep density gradient can be resolved. This technique is validated as a diagnostic for the investigation of warm dense plasmas, allowing an in situ characterization of high-density contrasted plasmas.

In this paper we describe experimental results on angularly resolved x-ray scatter from a sample of warm dense aluminium that has been created by double sided laser-driven shock compression. The experiment was carried out on the Central Laser Facility of the Rutherford Appleton Laboratory, using the VULCAN laser. The form of the angularly resolved scatter cross-section was compared with predictions based on a series of molecular dynamics simulations with an embedded atom potential, a Yukakwa potential and a bare Coulomb potential. The importance of screening is evident from the comparison and the embedded atom model seems to match experiment better than the Yukawa potential.

Laser facilities for fast ignition will require in excess of 50 kJ of short pulse laser energy. Based on the current contrast estimate for the NIF ARC laser system at LLNL, ignition scale systems will have pre-pulses at the ∼J level. This will produce a large scale-length plasma inside the reentrant fast ignition cone that could significantly influence the generation and transport of hot electrons towards the compressed fuel core. We present a study of cone wall and cone tip fluorescence measurements due to intense short pulse laser irradiation, as a function of pre-pulse from 1 mJ - 1 J. These experiments were performed using the Titan laser (2×1020W/cm2) at the Lawrence Livermore National Laboratory and the Vulcan laser (6×1020W/cm2) at the Rutherford Appleton Laboratory. The implicit hybrid particle-in-cell code LSP is used to translate these observables into estimates of hot electron production efficiency and transport.

The electromagnetic fields generated following the interaction of a 3 × 1019 W cm−2 infrared pulse with a gold wire have been investigated using the well-documented proton radiography diagnostic1. The pulse is observed to drive a transient current along the length of the wire, the spread velocity of which is confidently measured via a novel experimental arrangement to be ∼c. Within a temporal window of 20 ps, the current rises to its peak magnitude ∼104 A before decaying to below measurable levels. Both PIC simulation results and simple theoretical reasoning are used to demonstrate that the ultrafast target charging and transient current observed are a direct product of the permanent escape of a small fraction of the laser-accelerated hot electron population to vacuum.

The interaction of a $3\ifmmode\times\else\texttimes\fi{}{10}^{19}\text{ }\text{ }\mathrm{W}/{\mathrm{cm}}^{2}$ laser pulse with a metallic wire has been investigated using proton radiography. The pulse is observed to drive the propagation of a highly transient field along the wire at the speed of light. Within a temporal window of 20 ps, the current driven by this field rises to its peak magnitude $\ensuremath{\sim}{10}^{4}\text{ }\text{ }\mathrm{A}$ before decaying to below measurable levels. Supported by particle-in-cell simulation results and simple theoretical reasoning, the transient field measured is interpreted as a charge-neutralizing disturbance propagated away from the interaction region as a result of the permanent loss of a small fraction of the laser-accelerated hot electron population to vacuum.

International audience; We present the results of experiments in which jets are created through the collision of two laser-produced plasmas. These experiments use a simple `v-foil' target design: two thin foils are placed at an angle of 140° to each other, and irradiated with a high-energy laser. The plasmas from the rear face of these foils collide and drive plasma jets moving with a velocity of ˜300 km s-1. By choosing the foil thickness and material to suit the laser conditions available, it has proven possible to create plasma jets for which the relevant scaling parameters show significant overlap with those of outflows associated with young stellar objects (YSOs). Preliminary results are also shown from experiments to study the effect of an ambient gas on jet propagation. Nominally identical experiments are conducted either in vacuum or in an ambient medium of 5 mbar of nitrogen gas. The gas is seen to increase the jet collimation, and to introduce shock structures at the head of the outflow.

We have investigated the angular variation in elastic x-ray scattering from a dense, laser-shock-compressed aluminum foil. A comparison of the experiment with simulations using an embedded atom potential in a molecular dynamics simulation shows a significantly better agreement than simulations based on an unscreened one-component plasma model. These data illustrate, experimentally, the importance of screening for the dense plasma static structure factor. © 2008 The American Physical Society.

We have characterized the plasma produced by a picosecond laser pulse using x-ray spectroscopy. High-resolution high-sensitivity spectra of $K$-shell emission from a Ti plasma have been obtained, showing a strong contribution from multiply ionized ions. Hydrodynamic and collisional-radiative codes are used to extract the plasma temperature and density from these measurements. We show that our measurements can provide benchmarks for particle-in-cell (PIC) simulations of preplasma conditions in ultraintense laser-matter interactions.

International audience; In this paper, three different experimental configurations designed to study jet propagation physics are presented. Each configuration uses a different target design: conical dimples in solid surfaces, hollow cones filled with foam and angled thin foils. When irradiated with a laser, these targets result in the launching of a plasma jet, the properties of which can be controlled by judicious choices of the target and laser parameters. Experimental results from these targets are shown, and the physics which may be studied with each of these targets is briefly discussed.

We describe experiments designed to produce a bright M-L band x-ray source in the 3-3.5 keV region. Palladium targets irradiated with a 10(15) W cm(-2) laser pulse have previously been shown to convert up to similar to 2% of the laser energy into M-L band x-rays with similar pulse duration to that of the incident laser. This x-ray emission is further characterized here, including pulse duration and source size measurements, and a higher conversion efficiency than previously achieved is demonstrated (similar to 4%) using more energetic and longer duration laser pulses (200 ps). The emission near the aluminium K-edge (1.465-1.550 keV) is also reported for similar conditions, along with the successful suppression of such lower band x-rays using a CH coating on the rear side of the target. The possibility of using the source to radiatively heat a thin aluminium foil sample to uniform warm dense matter conditions is discussed.

We report on the successful demonstration of selective acceleration of deuterium ions by target-normal sheath acceleration (TNSA) with a high-energy petawatt laser. TNSA typically produces a multi-species ion beam that originates from the intrinsic hydrocarbon and water vapor contaminants on the target surface. Using the method first developed by Morrison, et al.,$^{1}$ an ion beam with $>$99$\%$ deuterium ions and peak energy 14 MeV/nucleon is produced with a 200 J, 700 fs, $>10^{20} W/cm^{2}$ laser pulse by cryogenically freezing heavy water (D$_{2}$O) vapor onto the rear surface of the target prior to the shot. Within the range of our detectors (0-8.5$^{\circ}$), we find laser-to-deuterium-ion energy conversion efficiency of 4.3$\%$ above 0.7 MeV/nucleon while a conservative estimate of the total beam gives a conversion efficiency of 9.4$\%$., 5 pages, 5 figures

We present measurements of a magnetic reconnection in a plasma created by two laser beams (1 ns pulse duration, 1 x 10(15) W cm(-2)) focused in close proximity on a planar solid target. Simultaneous optical probing and proton grid deflectometry reveal two high velocity, collimated outflowing jets and 0.7-1.3 MG magnetic fields at the focal spot edges. Thomson scattering measurements from the reconnection layer are consistent with high electron temperatures in this region.

The temporal evolution of the opacity of an iron plasma at high temperature (30--350 eV) and high density ($0.001--0.2\text{ }\text{ }\mathrm{g}\text{ }{\mathrm{cm}}^{\ensuremath{-}3}$) has been measured using a nickel-like silver x-ray laser at 13.9 nm. The hot dense iron plasma was created in a thin (50 nm) iron layer buried 80 nm below the surface in a plastic target that was heated using a separate 80 ps pulse of 6--9 J, focused to a $100\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ diameter spot. The experimental opacities are compared with opacities evaluated from plasma conditions predicted using a fluid and atomic physics code.

Experimental measurements of the opacity of plasmas at densities close to solid state and temperatures ~ 60 - 300 eV using a probing X-ray laser are presented. Utilizing thin targets, opacities of iron have been measured using x-ray lasers of photon energy 89 eV created by pumping with the VULCAN RAL laser. The thin targets are separately heated by spot focus laser pulses. We have demonstrated that X-ray laser brightness is sufficient to overcome the self-emission of hot plasma so that useful opacity measurements can be made. Due to their high brightness, x-ray lasers can fulfill a useful niche in measuring opacity and other phenomena associated with laser-plasma interactions. Quantities such as opacity measured in laser-plasmas are useful elsewhere. For example, plasma opacity is important in understanding radiative transfer in the sun.

We present differential x-ray scattering cross sections for a radiatively heated plasma showing overall consistency, in both form and absolute value, with theoretical simulations. In particular, the evolution of the plasma from a strongly coupled high density phase to a lower density weakly coupled phase is quite clearly shown in both experiment and simulation. The success of this experiment shows that x-ray scattering has the potential to become an extremely useful diagnostic technique for dense plasma physics.

This paper investigates the characteristic properties of a laser triggered micro-lens for focusing and energy selection of laser generated MeV proton and ion beams. Both experimental and computational studies that have been carried out leading to the understanding of the physical processes driving the micro-lens. After a one side irradiation of a hollow metallic cylinder a radial electric field develops inside the cylinder. Hot electrons generated by the interaction between laser pulse and cylinder wall spread inside the cylinder generating a plasma at the wall. This plasma expands into vacuum and sustains an electric field that acts as a collecting lens for proton or ion beams propagating axially through the cylinder. Various measurements including the reduction of the intrinsic beam divergence, the focusing quality, the energy selection and temporal response were carried out which contribute to the understanding of the lens properties. In addition, proton imaging was employed to study the electron transport inside the cylinder, revealing a transport along the wall surface. Each aspect studied experimentally is interpreted using 2D PIC and ray tracing simulations. A very good consistency between experimental and computational data was found. Refereed/Peer-reviewed

Measurements of the bidirectional plasma jets that form at the surface of a solid target during a laser-generated driven magnetic reconnection are presented. Resistivity enhancement of at least 25× the classical Spitzer value is required when applying the Sweet–Parker model of reconnection to reconcile the experimentally observed reconnection time scale. Analytic calculations show that a fast reconnection model, which includes a priori the effects of microturbulent resistivity enhancement, better reproduces the experimental observations.

Dense titanium plasma has been heated to an electron temperature up to 1300 eV with a 100 TW, high intensity short-pulse laser. The experiments were conducted using Ti foils (5 mu m thick) sandwiched between layers of either aluminum (1 or 2 mu m thick) or plastic (2 mu m thick) to prevent the effects of prepulse. Targets of two different sizes, i.e., 250 x 250 mu m(2) and 1 x 1 mm(2) were used. Spectral measurements of the Ti inner-shell emission, in the region between 4 and 5 keV, were taken from the front-side (i.e., the laser illuminated side) of the target. The data show large shifts in the K alpha emission from open-shell ions, suggesting bulk heating of the sample at near solid density, which was largest for reduced mass targets. Comparison with collisional radiative and 2D radiation hydrodynamics codes indicates a peak temperature of T-e,T-peak=1300 eV of solid titanium plasma in similar to 0.2 mu m thin layer. Higher bulk temperature (T-e,T-bulk=100 eV) for aluminum tamped compared to CH tamped targets (T-e,T-bulk=40 eV) was observed. A possible explanation for this difference is described whereby scattering due to the nuclear charge of the tamping material leads to modified electron transport behavior. (C) 2007 American Institute of Physics.

Summary form only given, as follows. Summary form only given. Accurate phase diagrams for simple molecular fluids (H/sub 2/, H/sub 2/O, NH/sub 3/ and CH/sub 4/) and their constituent elements at temperatures of several thousand Kelvin and pressures of several Mbar are integral to planetary models of the gas giant planets ( Jupiter, Saturn, Uranus and Neptune). Experimental data at high pressure has, until recently, been linuted to around 1 Mbar with both dynamic (ie. two-stage light-gas guns) and static (ie. diamond anvil cells) techniques. Current high intensity laser facilities can now produce tens of Mbar pressures in these light fluids, reaching the dense plasma states required for understanding the cores of giant planets and low mass stars. This presentation will first describe recent Hugoniot data for water at pressures up to 8 Mbar and carbon up to 30 Mbar At Hugoniot pressures near 1 Mbar, water transitions from an ionic to electronic conductor as observed from the shock front reflectivity. Pressure-densitytemperature data follow the Sesame database up to 8 Mbar where water is a dense plasma. Carbon starting from the chamond phase is shown to metallizes at Hugoniot pressures extending from 6 to 11 Mbar.