2004/08/03 by Justin Oelgoetz, Anil K. Pradhan · 2 citations
Physics and Astronomy · #Atomic and Molecular Physics #Laser-Plasma Interactions and Diagnostics #Solar and Space Plasma Dynamics #astro-ph #physics.atom-ph
paper · pdf · doi:10.1111/j.1365-2966.2004.08269.x
published as Mon.Not.Roy.Astron.Soc.354:1093-1102,2004 · 13 pages, 4 figures, 1 postscript coversheet. This is a preprint of an article accepted for publication in the Monthly Notices of the Royal Astronomical Society
arxiv created 2004/08/03 · openalex publication_date 2004/11/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Time‐dependent numerical simulations of the Kα complex of Fe xxv are carried out as a function of temperature–density–radiation field variations in high‐temperature astrophysical and laboratory plasmas. In addition to several well‐known features, the transient and steady‐state spectra reveal the effects due to (a) time‐dependent thermal and non‐thermal radiation fields, (b) photo‐ and collisional excitation and ionization, and (c) high densities, on the ‘quartet’ of principal w, x, y, z lines, and dielectronic satellites. The highly detailed models show precisely how, assuming a temporal–temperature correlation, the X‐ray intensity varies between 6.6 and 6.7 keV and undergoes a ‘spectral inversion’ in the w and z line intensities, characterizing an ionization‐ or a recombination‐dominated plasma. The dielectronic satellite intensities are the most temperature‐dependent features, but insensitive to density variations, and significantly contribute to the Kα complex for T < 6.7 keV leading to asymmetric profiles. The 6.7‐keV Kα complex should be a potential diagnostic of X‐ray flares in active galactic nuclei, afterglows in gamma‐ray bursts, and other non‐equilibrium sources with the high‐resolution measurements possible from the upcoming mission Astro‐E2. It is also shown that high electron densities attenuate the line intensities in simulations relevant to laboratory plasmas, such as in inertial confinement fusion, laser, or magnetic Z‐pinch devices.