Fig. 1. Experimental setup for radiography experiment. The nanosecond laser pulses are injected into the hohlraum to ablate the target, and the picosecond laser pulse provides the hard x-ray backlighter. The radiographic image is captured by imaging plates (IPs) placed in the hard x-ray imaging system (HXI).

Fig. 2. (a) and (b) Photographs of indirect drive double shell target. (c) Schematic of target cross section.

Fig. 3. Layout of experimental diagnostic equipment.

Fig. 4. Synthetic radiographs of the double shell target at different times with x rays of different energies. Time A: the target has not yet been compressed. Time B: the outer shell has just collided with the inner shell. Time C: the inner shell has been compressed to half the initial size. Time D: compression is maximum.

Fig. 5. (a)–(d) Synthetic transmitted x-ray signals through the target center from Figs. 4(a), 4(f), 4(k), and 4(l), respectively.

Fig. 6. Measured x-ray spectra of different shots.

Fig. 7. Measured time history of hohlraum radiation temperature.

Fig. 8. X-ray signals from the picosecond and nanosecond laser beams in shot 104. The optical fiducial pulses synchronized with the nanosecond laser are also presented.

Fig. 9. Time-resolved radiographic images of indirectly driven double shell targets. (a) Shot 105, only short-pulse laser, un-driven target. (b) Shot 104, t = 2.76 ns. (c) Shot 108, t = 4.45 ns.

Fig. 10. Calculated normalized radiation flux distribution on the capsule.

Fig. 11. (a) Schematic of DS target design, and simulated implosion trajectory of the indirect drive DS target. (b) Density distribution and its evolution with time.

Fig. 12. Predicted cross-sectional shape of the inner shell. The dashed line represents the data contour from Fig. 9(b).

Fig. 13. Response of image plates to photons with different energies.

Fig. 14. (a) Calculation of the transmission profile through the copper cylinder (black curve), and the measured profile from the experimental results (red curve). (b) Areal density distribution of the un-driven target. The solid curve was obtained using the radiography data, and further smoothing gave the dashed curve.

Fig. 15. (a) Intensity of PSL data through the target center region shown in Fig. 9(c). (b) Areal density distribution obtained near peak compression. The solid curve was calculated from the radiographic image, and further smoothing gave the dashed curve.

Fig. 16. (a) A series of energy spectra obtained by the Monte Carlo method. (b) Average transmittance and its uncertainty distribution corresponding to different areal densities.

Fig. 17. Comparison of PSLs on the FSS IPs from different shots.