Fig. 1. Schematic views of the target assembly: (a) side view of the laser–target interaction; (b) 3D visualization of a target assembly with laser cones.

Fig. 2. Comparison between variant target assemblies for different experiments on astrophysical flows: (a) design for experiments on flow collisions with static objects; (b) design for experiments on collisions of counter-propagating flows, also depicted in Figure 1(b).

Fig. 3. Representations of the microfabricated radiography backlighter: (a) schematic; (b) magnified view; (c) full view of the backlighter plate attached to a target assembly.

Fig. 4. Components of a target assembly for use inside a magnetic coil.

Fig. 5. 3D representations of a target assembly inserted into a split pair coil: (a) side view; (b) cross-section. The basic interaction that is studied remains the same as shown in Figure 1(a), with the laser focusing on a thin foil sample and generating a plasma flow in the center of the coils.

Fig. 6. Alignment bench used for alignment of a magnetic field target. The target assembly can be directly taken out of the bench and inserted into the coil, where it would sit at an already aligned position.

Fig. 7. Schematic of the experimental setup for the SG-II campaign. Four beams come from each side, each carrying 250 J of energy, for a total of 1 kJ. The separation between samples is 3.6 mm, and the beams on each side are set to different delays depending on the samples being studied, to ensure the resulting flows meet roughly at the middle of the observation window. The backlighter depicted follows the design shown in Figure 3, and the timing of its driver laser is determined depending on the expected velocity of the plasma flows.

Fig. 8. Target changes introduced to optimize the radiography diagnostic at SG-II. Both images show two colliding plasma flows, one formed from a 10 μm titanium foil, coming from the top, and one from a 6 μm polyethylene terephthalate (PET) foil, from the bottom. The latter cannot be seen in the radiography due to the low X-ray absorption of PET. The separation between the samples is 3.6 mm, but the initial 0.3 mm of propagation of each flow is blocked by the target body. In the initial case without shielding, the self-emission of the plasma plume that expands from the interaction area and that of trapped material inside gaps in the target body are able to reach the X-ray diagnostic, projecting a bright stripe into the radiography (a). By adding shielding and eliminating any of the gaps on the assembly, this emission can be blocked and the results are cleaner (b).

Fig. 9. Streaked optical self-emission of a single flow from a 10 μm aluminum sample, obtained during the SG-II campaign. The flow velocity can be calculated by tracking the maximum of the detected self-emission over time, and then fitting those points to a line using the least squares method. The flow in the image traverses 900 μm in 12 ns, which corresponds to the velocity of 75 km/s.

Fig. 10. Schematic of the experimental setup for the PALS campaign.

Fig. 11. Interferometry results for a flow from a 6 um aluminum foil under the conditions detailed in Figure 10 (a) with the target design for unmagnetized flows (Figure 2(a)), and with the magnetic field target (Figure 5) inserted inside the coil with (b) no field, (c) a 5 T field and (d) a 10 T field. All images are taken using a Grasshopper3 U3-28S4 charge-coupled device integrated over 0.3 ns. The limited space and exhaust capacities inside the magnetic field targets cause an accumulation of material visible in the interferograms.