Daniel Thorn | 18-ERD-015
Inertial confinement fusion (ICF) plasmas are characterized by several kiloelectron volt (keV) electron temperatures, as well as ion and electron densities approaching 100 to 1,000 times solid. In these implosions that simulate the dynamics of our sun, spectroscopic dopants can facilitate detailed exploration of the plasma gradients that are otherwise not possible. This is both in the central core pressure and temperature, as well as in any mix that results from ablation and hydrodynamic interactions.
Our work demonstrated that new Bayesian atomic physics models could be applied to ICF plasmas to give both the temperature and density of the internal hot spot. These new models better describe the physical nature of these implosions, along with providing the ability to spatially resolve the plasma mix coming from the ablator region. In addition, we demonstrated that this effect leads to a more quantitative description of mixed plasmas in inertial confinement plasmas. We have shown that we can gather and describe the mixed plasmas, as well as the interior hot-spot temperature density profiles, which allows for better constraints on the plasma description.
This work supports Lawrence Livermore National Laboratory's mission-relevant ICF work by enabling better validation of codes, and by providing a clear set of parameters for ICF design. In addition, the work supports the Laboratory's core competency in high-energy-density science by advancing spectral analysis techniques.
Publications, Presentations, and Patents
MacDonald, M. J., et al. 2018a. "Diagnosing hot-spot electron temperatures using x-ray continuum emission measurements on NIF and Omega implosions." 60th Annual Meeting of the APS Division of Plasma Physics, Portland, OR, November 2018. LLNL-PRES-760969
——— 2018b. "Diagnosing hot-spot electron temperatures using x-ray continuum emission measurements on NIF and Omega implosions." Radiative Properties of Hot Dense Matter, Hamburg, Germany, October 2018. LLNL-PRES-760348
——— 2019a. "Absolute calibration of the continuum x-ray spectrometer (ConSpec) at the National Ignition Facility." J. Instrum. 14, P12009. doi:10.1088/1748-0221/14/12/P12009. LLNL-JRNL-790347
———2019b. "Using multiple independent diagnostics to measure hot-spot electron temperatures of ICF implosions at the NIF." International Conference on High Energy Density, Oxford, England, March/April 2019. LLNL-PRES-771231
——— 2020. "Using multiple independent diagnostics to constrain hot-spot plasma conditions of ICF implosions at the NIF." Extreme Physics, Extreme Data, Leiden, Netherlands, January 2020. LLNL-PRES-801269
Thorn, D. B., et al. 2018a. "X-ray Spectrometer Throughput Model for Flat Bragg Crystal Spectrometers on Laser Plasma Facilities." Review of Scientific Instruments 89, 10F119. doi:10.1063/1.5039423. LLNL-CONF-751004
——— 2018b. "X-ray Spectrometer Throughput Model for Flat Bragg Crystal Spectrometers on Laser Plasma Facilities." 22nd Topical Conference on High-Temperature Plasma Diagnostics, San Diego, CA, April 2018. LLNL-POST-749822
——— 2019a. "X-ray Spectroscopy at NIF." Friedrich Schiller University, Jena, Germany, May 2019. LLNL-PRES-773884
——— 2019b. "X-Ray Detectors, Spectrometers, and Calibration at the National Ignition Facility." Weissman Institute, Rehovot, Israel, May 2019. LLNL-PRES-773883
——— 2019c. "NIF Spectral Calibration Facility," Atomic Physics Colloquium, Helmholtz Institute Jena and Friedrich Schiller University, Jena, Germany, May 2019. LLNL-PRES-773884
——— 2019d. "X-Ray Detectors, Spectrometers, and Calibration at the National Ignition Facility." Weissman Institute, Rehovot, Israel, May 2019. LLNL-PRES-773883
——— 2019e. "Spectroscopy of NIF implosions: Fitting to gradients and building analysis of differential emission measure and mass temperature distributions." International Fusion Sciences and Applications, Osaka, Japan, September 2019. LLNL-PRES-791110