Effects of Magnetic Fields on Transport in Laser-Driven Nonequilibrium Plasmas

Gregory Kemp | 17-ERD-027

Overview

We aimed to develop a deeper understanding of the effects of magnetic fields on laser-driven, high-Z, non-equilibrium plasmas, allowing an assessment of the benefits and risks for a variety of applications including magnetized inertial confinement fusion (ICF) concepts and high-photon-energy x-ray sources. X-ray optical Thomson scattering, laser backscatter, and proton radiography data gathered on the Jupiter, OMEGA, OMEGA-EP, and National Ignition Facility lasers over a broad range of plasma conditions provided invaluable data for model validation in a regime where little-to-no data had previously existed. Data collected is helping inform ongoing efforts to remove "knobs" from magneto-radiation-hydrodynamics modeling of high-energy-density plasmas, the results of which could benefit a broad range of Lawrence Livermore National Laboratory missions.

Impact on Mission

Our research leveraged and advanced Laboratory's core competency in high-energy-density (HED) science. Computation of HED environments relies heavily on incomplete or insufficient approximations of physical phenomena under extreme conditions where very little data exist to test the validity and applicability of those models. To this end, our work is helping fill gaps in understanding of externally-applied and self-generated magnetic field effects on thermal and laser energy transport, plasma conditions, laser-plasma instabilities, as well as self-generated magnetic field origins and evolution in regimes relevant to optimizing multi-keV x-ray sources and magnetized ICF designs, all of which are scientific issues of national importance.

Publications, Presentations, Etc.

Colvin, J., et al. 2018. "The Effects of Microstructure on Propagation of Laser-Driven Radiative Heat Waves in Under-Dense High-Z Plasma." Physics of Plasmas 25 (3):032702. doi: 10.1063/1.5012523. LLNL-JRNL-740992.

Giuliani, J., et al. 2016. "Heat Loss in a Laser-Driven, Magnetized, X-Ray Source with Thermoelectric Terms." Bulletin of the American Physical Society . LLNL-ABS-697630.

Heeter, R., et al. 2018. "FY18 LLNL Experimental Programs at Omega. " Technical Report. Lawrence Livermore National Laboratory, Livermore, CA. LLNL-TR-763329.

Kemp, G., et al. 2016. "Simulation Study of Enhancing Laser Driven Multi-KeV Line-Radiation through Application of eExternal Magnetic Fields." Physics of Plasmas 23 (10):101204. doi: 10.1063/1.4965236. LLNL-JRNL-692158.