Non-LTE and gradient effects in K-shell oxygen emission laser-produced plasma

A recent effort [1] to develop a high-resolution spectroscopy capability for He-like and H-like ions to study far wing shapes from a laser-produced plasma experiment at the Lawrence Livermore National Laboratory found unexpected structure in the observed emission from a Mylar target. In this paper we propose that the observed features are due to exotic inner-shell transitions in mid-ionized oxygen, suggesting that the observed emission arises from two plasma regions: a hotter, less dense outer region gives rise to the observed He-like and H-like resonance lines, while a cooler, more dense plasma region closer to the target surface and in a region surrounding the laser spot generates the dielectronic satellites and the exotic inner-shell lines. Calculations using the Los Alamos suite of atomic physics codes and the plasma kinetics code ATOMIC are used to support this assertion.