Visualization of Shock Front Deformities in Fusion Ablator Materials Using Streaked Optical Pyrometry

Because of the abundance of fuel materials and promising energy yield, nuclear fusion may be the answer to the world's growing energy demands. Inertial Confinement Fusion (ICF) is one of the most promising options for nuclear fusion energy. As shock waves pass through ICF target capsule ablators, voids and other imperfections cause instabilities in the shock front leading to reduced energy gains. Studying shock-bubble (SB) interactions gives insights into how defects in ICF target capsules affect ICF reactions. In this study, we investigated how an ICF ablator-like material with voids between 20-40 μm reacted under laser driven shock. We detected an optical emission on our Velocity Interferometer System for Any Reflector (VISAR) streak camera and deduced that it was thermal emission resulting from the shock wave heating the ablator. We further found that the shock wave was accelerated through the void (by jetting as the void collapsed) leading to an inhomogeneous shock front. We hope that this will lead to a better understanding of hydrodynamic instabilities that reduce ICF energy gain.