X-ray Spectroscopy of K- and L-shell Z-pinch and Astrophysical Plasmas

Journal Article · Thu Sep 10 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3241192· OSTI ID:21344615

Dasgupta, A; Davis, J; Giuliani, J G ^[1]; Clark, R W ^[2]

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1. Plasma Physics Division, Naval Research Laboratory, Washington DC 20375 (United States)
2. Berkeley Research Associates, Beltsville, Maryland 20705 (United States)

In recent years, there have been significant advances in instrumental capabilities for making X-ray spectroscopic measurements of astrophysical plasmas. There have been corresponding improvements in X-ray diagnostics for advanced multi-mega-ampere pulse power machines that produce increasingly large radiative yields from gas-puff and wire array Z pinch plasmas. Analysis used for Z pinches can be used to study ICF and also astrophysical plasmas where laboratory measurements and simulations are the only means to interpret observed data. The astrophysical data for Fe, the most cosmically abundant high Z element, can provide a wealth of information about cosmic plasmas. Fe is also the key element in stainless steel (SS) wire arrays that are investigated as an intense X-ray radiation source at the Z machine at Sandia National Laboratories. The implosion dynamics of an array of wires on the Z and/or refurbished Z accelerator produces an abundance of radiation from the K- and L-shell ionization stages. These dynamic plasmas are inherently non-LTE, with opacity and other factors influencing the X-ray output. As the plasma assembles on axis, a number of time resolved snapshots provide temperature and density profiles and map the emitting region. We will analyze the ionization dynamics and generate K- and L-shell spectra using the conditions generated in the Z and/or refurbished Z accelerator, described by a 1-D non-LTE radiation-hydrodynamics model. Diagnostics based on spectral shape of L-shell emissions are inherently more difficult than those based on K-shell emissions because of more complex multiplet structures and line overlaps. The non-LTE populations are obtained by using detailed atomic models that include all important excitation, ionization, and recombination processes. We will highlight the connection between laboratory Z-pinch plasma simulations and astrophysical plasmas.

• OSTI ID: 21344615
• Journal Information: AIP Conference Proceedings, Vol. 1161, Issue 1; Conference: 16. international conference on atomic processes in plasmas, Monterey, CA (United States), 22-26 Mar 2009; Other Information: DOI: 10.1063/1.3241192; (c) 2009 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTROPHYSICS
COMPUTERIZED SIMULATION
EXCITATION
HYDRODYNAMICS
INERTIAL CONFINEMENT
IONIZATION
K SHELL
L SHELL
LONGITUDINAL PINCH
OPACITY
PHOTON EMISSION
PLASMA
PLASMA DIAGNOSTICS
PLASMA SIMULATION
RECOMBINATION
SANDIA NATIONAL LABORATORIES
THERMODYNAMICS
TIME RESOLUTION
X-RAY SPECTROSCOPY
CONFINEMENT
ELECTRONIC STRUCTURE
EMISSION
ENERGY-LEVEL TRANSITIONS
FLUID MECHANICS
MECHANICS
NATIONAL ORGANIZATIONS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PHYSICS
PINCH EFFECT
PLASMA CONFINEMENT
RESOLUTION
SIMULATION
SPECTROSCOPY
TIMING PROPERTIES
US DOE
US ORGANIZATIONS