Theoretical and experimental investigation of the equation of state of boron plasmas
Abstract
We report a theoretical equation of state (EOS) table for boron across a wide range of temperatures (5.1 ×104 -5.2 ×108 K) and densities (0.25-49 g/cm3) and experimental shock Hugoniot data at unprecedented high pressures (5608 ±118 GPa). The calculations are performed with first-principles methods combining path-integral Monte Carlo (PIMC) at high temperatures and density-functional-theory molecular-dynamics (DFT-MD) methods at lower temperatures. PIMC and DFT-MD cross-validate each other by providing coherent EOS (difference <1.5 Hartree/boron in energy and <5 % in pressure) at 5.1 ×105 K. The Hugoniot measurement is conducted at the National Ignition Facility using a planar shock platform. The pressure-density relation found in our shock experiment is on top of the shock Hugoniot profile predicted with our first-principles EOS and a semiempirical EOS table (LEOS 50). We investigate the self-diffusivity and the effect of thermal and pressure-driven ionization on the EOS and shock compression behavior in high-pressure and -temperature conditions. We also study the sensitivity of a polar direct-drive exploding pusher platform to pressure variations based on applying pressure multipliers to LEOS 50 and by utilizing a new EOS model based on our ab initio simulations via one-dimensional radiation-hydrodynamic calculations. The results are valuable for future theoretical and experimental studies and engineering design in high-energy density research.
- Publication:
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Physical Review E
- Pub Date:
- August 2018
- DOI:
- 10.1103/PhysRevE.98.023205
- arXiv:
- arXiv:1804.11322
- Bibcode:
- 2018PhRvE..98b3205Z
- Keywords:
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- Physics - Plasma Physics;
- Astrophysics - Solar and Stellar Astrophysics;
- Condensed Matter - Materials Science;
- Physics - Computational Physics
- E-Print:
- 12 pages, 9 figures, 2 tables