X-ray “burn through” studies for symmetry control considerations in support of magnetic-indirect-drive fusion platform development*

Numerical simulations investigating the dependence of shine-shield material and thickness for mode-selective, time-dependent control of P2 and P4 Legendre mode asymmetries for magnetic-indirect-drive (MID) target designs are presented. The MID concept uses a plasma pinch to create x-rays within a primary hohlraum directing them into a secondary hohlraum where the resultant bath of x rays ablates and compresses a capsule containing deuterium and tritium fuel to high temperatures, creating fusion [T. W. L. Sanford et al., Physical Review Letters 83, 5511 (1999)]. A shine-shield is used to control the radiation flow from the primary to the secondary hohlraum and shape the implosion drive, including eliminating the pole-hot x-ray flux that would otherwise be seen by the capsule. We describe design options and the feasibility for exercising time-dependent control over low-mode asymmetries that are independent of hohlraum length.