Abstract
During the first few hundred picoseconds of indirect drive for inertial confinement fusion on the National Ignition Facility, x-ray spots formed on the hohlraum wall when the drive beams cast shadows of the fuel fill-tube on the capsule surface. Differential ablation at the shadow boundaries seeds perturbations which are hydrodynamically unstable under subsequent acceleration and can grow to impact capsule performance. We have characterized this shadow imprint mechanism and demonstrated two techniques to mitigate against it using (i) a reduced diameter fuel fill-tube, and (ii) a pre-pulse to blow down the fill-tube before the shadow forming x-ray spots from the main outer drive beams develop.
| Original language | English (US) |
|---|---|
| Article number | 082702 |
| Journal | Physics of Plasmas |
| Volume | 25 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 1 2018 |
| Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics