Laboratory photoionized plasma experiments at Z relevant to astrophysics

ORAL

Abstract

Photoionized plasmas are present in many astrophysical environments, such as accretion disks and radiatively-driven winds of x-ray binaries and active galactic nuclei. We discuss an experimental and modeling effort in which the intense x-ray flux emitted at the collapse of a z-pinch is employed to produce and backlight a neon photoionized plasma to study the atomic kinetics through K-shell line absorption spectroscopy. The plasma is contained in a cm-scale gas cell filled with neon and placed at various distances from the z-pinch. The filling pressure is monitored in situ thus providing the particle number density of the plasma. High-resolution spectra are recorded with a TREX spectrometer with two elliptically-bent KAP crystals and a set of slits to record up to six spectra per crystal per shot. The transmission data shows line absorption transitions in several ionization stages of neon including Be-, Li-, He- and H-like ions. Analysis of the transmission spectra yields the charge state distribution and ion areal-densities used to benchmark atomic kinetics calculations. In addition, the electron temperature extracted from a level population ratio is used to test heating models of the photoionized plasma.

*This research was sponsored in part by the National Nuclear Security Administration under the High Energy Density Laboratory Plasmas grant program through DOE Grant DE-FG52-09NA29551, and SNL.

Authors

  • Daniel Mayes

    • University of Nevada, Reno
    • University of Nevada, Reno Physics Department
  • T. Lockard

    • University of Nevada, Reno
  • T. Durmaz

    • University of Nevada, Reno
  • I. Hall

    • University of Nevada, Reno
  • R. Mancini

    • University of Nevada, Reno
  • J. Bailey

    • Sandia National Laboratories
  • G. Rochau

    • Sandia National Laboratories
  • D. Cohen

    • Swarthmore College
  • R. Heeter

    • Lawrence Livermore National Laboratory
  • D. Liedahl

    • Lawrence Livermore National Laboratory