title: Accuracy of K-shell spectra modeling in high-density plasmas
abstract: We present spectroscopic measurements of the helium-like and lithium-like argon emission supported by Thomson scattering diagnostics on gas bag targets. These data provide critical tests of plasma spectroscopic K-shell models. In particular, we have measured the line radiation in the wavelength region of the He-like Ar 1s(2)-1s3l transition (He-beta) that is of interest for density and temperature measurements of plasmas from gas-filled targets (n(e)</=10(21) cm(-3)), laser ablation targets (n(e)</=10(22) cm(-3)), and inertial confinement fusion capsule implosions (n(e)>/=10(24) cm(-3)). The spectra show lithium-like dielectronic satellites on the red wing of the He-beta line that are temperature sensitive and are known to influence the shape of the Stark-broadened line profiles observed from implosions. To examine the kinetics modeling of this complex, i.e., the He-beta and its associated satellites, we have performed experiments in gas bag plasmas at densities of (0.6-1.1)x10(21) cm(-3) where we independently determine the electron temperature with ultraviolet Thomson scattering. The comparison of the satellite intensities with kinetics modeling shows good agreement for satellites whose upper states are populated by dielectronic capture, but shows discrepancies for inner-shell collisional excited transitions.
authors.affiliation: L-437, Lawrence Livermore National Laboratory, University of California, P. O. Box 808, Livermore, California 94551 and CEA/DAM-Ile de France, Boiinsertion markte Postale 12, 91680 Bruyeres-le-Chainsertion marktel, France.
authors.initials: SH
authors.lastname: Glenzer
authors.initials: KB
authors.lastname: Fournier
authors.initials: C
authors.lastname: Decker
authors.initials: BA
authors.lastname: Hammel
authors.initials: RW
authors.lastname: Lee
authors.initials: L
authors.lastname: Lours
authors.initials: BJ
authors.lastname: MacGowan
authors.initials: AL
authors.lastname: Osterheld