Pulsed-power-driven high energy density physics and inertial confinement fusion research

M. K. Matzen, M. A. Sweeney, R. G. Adams, J. R. Asay, J. E. Bailey, Guy R. Bennett, David E. Bliss, D. D. Bloomquist, Thomas Brunner, R. B. Campbell,

Physics of Plasmas · 2005 · 314 citations · 133 references

Concepts

TL;DR

The Z accelerator at Sandia National Laboratories delivers ~20 MA load currents, generating magnetic fields exceeding 1000 T and megabar‑to‑gigabar pressures for high‑energy‑density physics and inertial confinement fusion research. The project aims to upgrade the Z accelerator over five years, targeting nearly 3 MJ x‑ray output at >300 TW by 2007. Using a z‑pinch configuration, the Z accelerator’s magnetic pressure supersonically implodes a wire‑array plasma to achieve ~10 MJ cm⁻³ energy densities and >1 keV temperatures, while alternative setups drive isentropic compression to >3 Mbar and accelerate flyer plates to >30 km s⁻¹ for EOS studies, with research conducted in collaboration worldwide. The Z accelerator produces ~2 MJ x‑ray energies at >200 TW, enabling ICF capsule implosions with improved symmetry and neutron yield, and a range of HEDP experiments such as radiation‑driven jets, EOS up to 10 Mbar, phase transitions, material strength studies, and detailed z‑pinch wire‑array dynamics, supported by advanced radiation‑magnetohydrodynamic simulations.

Abstract

The Z accelerator [R. B. Spielman, W. A. Stygar, J. F. Seamen et al., Proceedings of the 11th International Pulsed Power Conference, Baltimore, MD, 1997, edited by G. Cooperstein and I. Vitkovitsky (IEEE, Piscataway, NJ, 1997), Vol. 1, p. 709] at Sandia National Laboratories delivers ∼20MA load currents to create high magnetic fields (>1000T) and high pressures (megabar to gigabar). In a z-pinch configuration, the magnetic pressure (the Lorentz force) supersonically implodes a plasma created from a cylindrical wire array, which at stagnation typically generates a plasma with energy densities of about 10MJ∕cm3 and temperatures >1keV at 0.1% of solid density. These plasmas produce x-ray energies approaching 2MJ at powers >200TW for inertial confinement fusion (ICF) and high energy density physics (HEDP) experiments. In an alternative configuration, the large magnetic pressure directly drives isentropic compression experiments to pressures >3Mbar and accelerates flyer plates to >30km∕s for equation of state (EOS) experiments at pressures up to 10Mbar in aluminum. Development of multidimensional radiation-magnetohydrodynamic codes, coupled with more accurate material models (e.g., quantum molecular dynamics calculations with density functional theory), has produced synergy between validating the simulations and guiding the experiments. Z is now routinely used to drive ICF capsule implosions (focusing on implosion symmetry and neutron production) and to perform HEDP experiments (including radiation-driven hydrodynamic jets, EOS, phase transitions, strength of materials, and detailed behavior of z-pinch wire-array initiation and implosion). This research is performed in collaboration with many other groups from around the world. A five year project to enhance the capability and precision of Z, to be completed in 2007, will result in x-ray energies of nearly 3MJ at x-ray powers >300TW.

References

133