Mode 1 drive asymmetry in inertial confinement fusion implosions on the National Ignition Facility
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States)
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
- Laboratory for Laser Energetics, 250 E. River Road Rochester, New York 14623-1212 (United States)
Mode 1 radiation drive asymmetry (pole-to-pole imbalance) at significant levels can have a large impact on inertial confinement fusion implosions at the National Ignition Facility (NIF). This asymmetry distorts the cold confining shell and drives a high-speed jet through the hot spot. The perturbed hot spot shows increased residual kinetic energy and reduced internal energy, and it achieves reduced pressure and neutron yield. The altered implosion physics manifests itself in observable diagnostic signatures, especially the neutron spectrum which can be used to measure the neutron-weighted flow velocity, apparent ion temperature, and neutron downscattering. Numerical simulations of implosions with mode 1 asymmetry show that the resultant simulated diagnostic signatures are moved toward the values observed in many NIF experiments. The diagnostic output can also be used to build a set of integrated implosion performance metrics. The metrics indicate that P{sub 1} has a significant impact on implosion performance and must be carefully controlled in NIF implosions.
- OSTI ID:
- 22253287
- Journal Information:
- Physics of Plasmas, Vol. 21, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
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