The high-foot implosion campaign on the National Ignition Facility

• Published in: Physics of plasmas 2014-05, Vol.21 (5)
• Main Authors: Hurricane, O. A., Callahan, D. A., Casey, D. T., Dewald, E. L., Dittrich, T. R., Döppner, T., Barrios Garcia, M. A., Hinkel, D. E., Berzak Hopkins, L. F., Kervin, P., Pape, S. Le, Ma, T., MacPhee, A. G., Milovich, J. L., Moody, J., Pak, A. E., Patel, P. K., Park, H.-S., Remington, B. A., Robey, H. F.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALPHA PARTICLES; CONTROL; DEUTERIUM; GAIN; IMPLOSIONS; INERTIAL CONFINEMENT; INSTABILITY; LASERS; PLASMA HEATING; PULSE SHAPERS; SIMULATION; TRITIUM; US NATIONAL IGNITION FACILITY; YIELDS
• ISSN: 1070-664X; 1089-7674
• DOI: 10.1063/1.4874330

The “High-Foot” platform manipulates the laser pulse-shape coming from the National Ignition Facility laser to create an indirect drive 3-shock implosion that is significantly more robust against instability growth involving the ablator and also modestly reduces implosion convergence ratio. This strategy gives up on theoretical high-gain in an inertial confinement fusion implosion in order to obtain better control of the implosion and bring experimental performance in-line with calculated performance, yet keeps the absolute capsule performance relatively high. In this paper, we will cover the various experimental and theoretical motivations for the high-foot drive as well as cover the experimental results that have come out of the high-foot experimental campaign. At the time of this writing, the high-foot implosion has demonstrated record total deuterium-tritium yields (9.3×10{sup 15}) with low levels of inferred mix, excellent agreement with implosion simulations, fuel energy gains exceeding unity, and evidence for the “bootstrapping” associated with alpha-particle self-heating.