54th Annual Meeting of the APS Division of Plasma Physics
Volume 57, Number 12
Monday–Friday, October 29–November 2 2012;
Providence, Rhode Island
Session BI3: ICF Implosions, Diagnostics, Laboratory Shocks
9:30 AM–12:30 PM,
Monday, October 29, 2012
Room: Ballroom BC
Chair: Charles Nakhleh, Sandia National Laboratories
Abstract ID: BAPS.2012.DPP.BI3.2
Abstract: BI3.00002 : Integrated Diagnostic Analysis of ICF Capsule Performance
10:00 AM–10:30 AM
Preview Abstract
Abstract
Author:
Charles Cerjan
(Lawrence Livermore National Laboratory)
An understanding of the dynamics of imploding Inertial Confinement Fusion (ICF) capsules is crucial to achieve high convergence and gain. The relative roles of laser irradiation, hohlraum drive, and capsule response are intertwined and will be difficult to disentangle unless appropriate diagnostic probes are fielded and their results correlated. In the case of capsule implosions, several currently deployed diagnostics provide important information about the size and shape of the developing hot spot through x-ray self-emission, neutron production and average ion temperature by neutron time-of-flight signals, shell material mix into the hot spot by high-resolution x-ray spectra, and remaining mass during convergent ablation by x-ray backlighting. Obtaining a physically consistent picture of the implosion dynamics requires an integration of these disparate experimental data. This talk describes a three-dimensional model that attempts this integration. Assuming pressure equilibrium at peak compression and invoking simple radiative and equation-of-state relations, the pressure, density and electron temperature are obtained by optimized fitting of the experimental output to simple, global functional forms. The fitting procedure is sufficiently flexible to incorporate typical observational data such as x-ray self-emission, neutron time-of-flight signals, neutron yield, high-resolution x-ray spectra and radiographic images. Once consistency is obtained, many important secondary quantities can be derived such as the fuel areal density, high energy x-ray emission, neutron images, and nuclear activation. This approach has been validated by comparison with radiation-hydrodynamic simulations, producing semi-quantitative agreement and is now routinely used to characterize cryogenic implosion experiments. This talk will provide an overview of the implementation of the model and describe its application to recent experimental data.\\[4pt]
In addition to my collaborators Paul Springer and Scott Sepke, the author would like to thank many scientists for their assistance: J. Knauer, J. McNaney, M. Moran, D. Munro, G. Kyrala, D. Bradley, N. Izumi, T. Ma, S. Glenn, D. Clark, O. Jones, R. Town and S. Weber. This work was performed under the auspices of the U. S. Department of Energy by the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.DPP.BI3.2