Publications

Root, Seth R.; Magyar, Rudolph J.; Cochrane, Kyle C.; Mattsson, Thomas M.; Flicker, Dawn G.

Abstract not provided.

Physical Review B - Condensed Matter and Materials Physics

Magyar, Rudolph J.; Root, Seth R.; Cochrane, Kyle C.; Mattsson, Thomas M.; Flicker, Dawn G.

Mixtures of light elements with heavy elements are important in inertial confinement fusion. We explore the physics of molecular scale mixing through a validation study of equation of state (EOS) properties. Density functional theory molecular dynamics (DFT-MD) at elevated temperature and pressure is used to obtain the thermodynamic state properties of pure xenon, ethane, and various compressed mixture compositions along their principal Hugoniots. To validate these simulations, we have performed shock compression experiments using the Sandia Z-Machine. A bond tracking analysis correlates the sharp rise in the Hugoniot curve with the completion of dissociation in ethane. The DFT-based simulation results compare well with the experimental data along the principal Hugoniots and are used to provide insight into the dissociation and temperature along the Hugoniots as a function of mixture composition. Interestingly, we find that the compression ratio for complete dissociation is similar for several compositions suggesting a limiting compression for C-C bonded systems.

Physical Review B - Condensed Matter and Materials Physics

Mattsson, Thomas M.; Root, Seth R.; Mattsson, Ann E.; Shulenburger, Luke N.; Magyar, Rudolph J.; Flicker, Dawn G.

We use Sandia's Z machine and magnetically accelerated flyer plates to shock compress liquid krypton to 850 GPa and compare with results from density-functional theory (DFT) based simulations using the AM05 functional. We also employ quantum Monte Carlo calculations to motivate the choice of AM05. We conclude that the DFT results are sensitive to the quality of the pseudopotential in terms of scattering properties at high energy/temperature. A new Kr projector augmented wave potential was constructed with improved scattering properties which resulted in excellent agreement with the experimental results to 850 GPa and temperatures above 10 eV (110 kK). Finally, we present comparisons of our data from the Z experiments and DFT calculations to current equation of state models of krypton to determine the best model for high energy-density applications.

Carpenter, John H.; Root, Seth R.; Cochrane, Kyle C.; Flicker, Dawn G.; Mattsson, Thomas M.

Abstract not provided.

Mattsson, Thomas M.; Root, Seth R.; Shulenburger, Luke N.; Cochrane, Kyle C.; Wills, Ann E.; Wixom, Ryan R.; Flicker, Dawn G.

Abstract not provided.

Davis, Jean-Paul D.; Lane, James M.; Thompson, Aidan P.; Drake, Richard R.; Weirs, Vincent G.; Flicker, Dawn G.; Robbins, Joshua R.; Lemke, Raymond W.; Martin, Matthew; Alexander, Charles S.; Haill, Thomas A.; Ao, Tommy A.; Dolan, Daniel H.

Abstract not provided.

Mattsson, Thomas M.; Root, Seth R.; Magyar, Rudolph J.; Wills, Ann E.; Shulenburger, Luke N.; Flicker, Dawn G.

Abstract not provided.

Magyar, Rudolph J.; Root, Seth R.; Haill, Thomas A.; Mattsson, Thomas M.; Flicker, Dawn G.

Abstract not provided.

Carpenter, John H.; Flicker, Dawn G.; Root, Seth R.; Magyar, Rudolph J.; Mattsson, Thomas M.

Abstract not provided.