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A low inductance vacuum spark has been used to produce and excite ions of elements from chromium through copper. The line emission from these ions between 8 AA and 18 AA has been analysed with a bent crystal spectrograph used in the defocused de Broglie configuration. Numerous new emission lines have been recorded and their wavelengths measured. Most of these new features are identified as transitions in ions isoelectronic with Ne I, F I, and O I.
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Swartz et al. (1971) studied this question.
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