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 t wo laser-entrance-holes in hohlraums irradiated by the Nova laser [E. M. Campbell et al., Rev. Sci. Instrum. 57, 2101 (1986)]. By varying th e disk radii a never means of tuning the x-ray drive flux asymmetry is provided. Predicted implosion asymmetry is experimentally validated o ver a wide range of disk radii. Although simulations suggest increased x-ray drive onto the capsule in the presence of gold disks, neutron-b ased diagnostics are inconclusive in this regard. (C) 1996 American In stitute of Physics.