Novel symmetry tuning in Nova hohlraums using axial gold disks

A pair of axial gold disks is used to reduce the capsule view of the two laser‐entrance‐holes in hohlraums irradiated by the Nova laser [E. M. Campbell et al., Rev. Sci. Instrum. 57, 2101 (1986)]. By varying the disk radii a novel means of tuning the x‐ray drive flux asymmetry is provided. Predicted implosion asymmetry is experimentally validated over a wide range of disk radii. Although simulations suggest increased x‐ray drive onto the capsule in the presence of gold disks, neutron‐based diagnostics are inconclusive in this regard.

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