The extreme-ultraviolet spectrum of Fe xv in a solar flare

Approximately 13 lines of Fe xv are identified between 200 and 500 A in the slitless spectrum of a solar flare. Some of these are previously unclassified transitions from the experimentally unknown 3s3d 1D2 and 3p2 1D2 levels. Tbe intercombination lines 3s3p ,2-3P2 1D2 check the position of the P levels and confirm the classification of the intersystem line at 417.24 A. Classification is made through comparison with HX calculated spectra of Fe xv and through comparison with isoelectronic laboratory spectra. The population of the metastable levels of 3s3p P is calculated as a function of electron density, and n = 4 x 1010 in the flare is derived from the intensity ratio of the lines at 234 and 244 A. Several new singlet lines of Fe xv are identified in nonflare solar slit spectra below 100 A. The problem of the identification of the strong enhancing line at 69.66 A is discussed. Subject headings: flares, solar - line identifications spectra, ultraviolet