Shock generation comparison with planar and hemispherical targets in shock ignition relevant experiment

We performed an experiment on the "Ligne d'Intégration Laser" facility to produce strong shocks with plasma conditions relevant for the Shock Ignition approach to Inertial Confinement Fusion. Two kinds of targets have been used: planar and hemispherical. We observe an increase in the shock velocity in hemispherical geometry, which entails a fairly planar shock despite the Gaussian focal spot. Numerical results reproduce the shock dynamics in the two cases in a successful way, indicating, for laser intensities around 1.5 × 10¹⁵ W/cm² at 3ω, an ablation pressure of (90 ± 20) Mbar and (120 ± 20) Mbar in planar and hemispherical geometry, respectively.