Fig. 1. PFT target assembly.

Fig. 2. Detailed view of the upper portion of a PFT target assembly.

Fig. 3. PFT assembly. (All dimensions are in millimeters.)

Fig. 4. (a) Image of a PFT target assembly with a GDP permeation cell and HDC nonpermeable target capsule; (b) image of a PFT assembly with a GDP permeation cell and GDP target capsule.

Fig. 5. PFT assembly located inside a copper layering sphere.

Fig. 6. Image of single crystal seed that grows out of the fill tube. The initial growth of a single ring is indicative of a final ice layer that will be composed of a single hcp crystal, which is required for high-yield ICF implosions^[10].

Fig. 7. (a) An image of a final single-hcp-crystal ice layer characterized by optical backlit shadowgraphy; (b) the inner ice surface radius is shown in red and the outer ice surface radius in blue.

Fig. 8. Model geometry near the target capsule.

Fig. 9. Image of the fine mesh required to resolve the solid/gas phase boundary near the target capsule.

Fig. 10. Modeled temperature contours of the target and copper layering sphere.

Fig. 11. The ice/gas phase boundary predicted by the model (DT ice is shown in red).

Fig. 12. Unwrapped image of the model prediction of ice thickness overlaid on actual ice thickness; the fill tube is located at ${\sim}50^{\circ }$.

Fig. 13. Unwrapped image of the model prediction of ice thickness for three different fill-tube cross-sections with a GDP shell having a thermal conductivity of $0.05~\text{W}~\text{m}^{-1}~\text{K}^{-1}$.

Fig. 14. Unwrapped image of the model prediction of ice thickness for three different shell thermal conductivities with a 20-$\unicode[STIX]{x03BC}$m-OD, 10-$\unicode[STIX]{x03BC}$m-ID borosilicate fill tube.