Identifications of some highly-ionized iron and nickel lines in the 200 400 Å region of the solar spectrum
A number of previously unclassified multiplets of Fe xiv, xiii, xii, and xi produced by transitions of the type 3s 23p n -3s3p n+1 are identified in the XUV spectrum of the Sun. The iron lines account for most of the previously unidentified strong lines between 330 and 370 Å. Solar observations of especial value for the investigation of the 300 400 Å region were the slitless spectroheliograms of September 22, 1968 (Purcell and Tousey, 1969) and November 4, 1969 (Tousey, 1971) — on which the image of a flare was recorded. Other solar identifications in the same spectral region include the resonance lines of Ni xvii and Ni xviii, and one 3p-3d multiplet of Fe xiii. The solar blend at 417 Å involving the Fe xv inter-combination line and S xiv is resolved.