Hydrodynamic target experiments with proton beams at KALIF: Diagnostics of the ablation pressure by laser Doppler interferometry; Generation of multi-Mbar pressures by ablative foil acceleration and impact

The hydrodynamic response of plane targets to the ablative pressure impulse induced by high-power proton beams has been investigated experimentally at the KALIF facility using time-resolved laser Doppler interferometry. With this KALIF-ORVIS diagnostics system, it has been possible to measure the complete wave form of the ablation pressure pulse, p_abl(t) generated in aluminum at the boundary to the condensed target matter. In another class of experiments, the ablative acceleration of plane target foils to hypervelocities has been investigated. The proof-of-principle experiments have been performed at KALIF using a 20 cm-B_Θ extraction diode delivering an axial proton beam of 0.2 TW/cm² power density on target. Ablation pressure amplitudes of 0.3 Mbar have been determined, and 1-dimensional foil acceleration at >; 10¹¹ g up to 13 km/s final velocity has been achieved. Using these ablation flyer foils, impact experiments have been performed and diagnosed. Dynamic pressure states of 5 Mbar have been generated by impact of Al flyer foils with W targets. The experiments are being continued using the KALIF applied B extraction diode which delivers 50 kJ-proton beam pulses with 1 TW/cm² power density on target. In a third class of beam-target experiments at KALIF, the tensile strength of solids (Al, Mo single crystals) has been investigated up to the highest strain rates so far achieved in dynamic matter research.