Hydrodynamic Growth of Perturbations Seeded by Isolated Defects*

The hydrodynamic growth of pre-imposed isolated surface defects has been measured on the Nike laser. The defects had characteristic sizes of < 1 to 10's of μm, consistent with

typical spatial scales of inertial confinement fusion isolated target defects. High resolution monochromatic xray imagers captured streaked and two-dimensional images of the perturbation growth. High resolution FASTRAD3D simulations have been compared to experimental results, reproducing trends observed with varied defect size, laser drive. The

walls of the isolated bubble were observed ahead of the target while the spikes grew obliquely in towards the centerline of the defect, behind the accelerated part of the target. The latter observation suggests the use of areal density measurements alone are an insufficient diagnostic for measurements of isolated defect perturbation growth in inertial confinement fusion experiments.