Alternative fuel fill-tube geometry in relation to the mitigation of hydrodynamic instabilities in ICF implosions*

Engineering features on the capsule (gas fill tubes, support structures, etc.) introduce outer surface perturbations that can be ultimately detrimental to the performance of the capsule. Recent experiments have assessed minimal support structures, alternate pulse shapes and their effect in gas filled implosions. In this presentation the effect of the gas fill line in High Density Carbon implosions has been explored with a focus on a “tilted” geometry. This "tilted fill tube" enters the capsule shell at a shallow angle instead of perpendicularly to the shell surface. We present experiments that show the effect of this geometry and the benefit to reduce the overall perturbation caused by the fill tube.