Cr, Co, and Ni transitions isoelectronic to the Fe xxiv – Fe xvii lines around 11 Å in laser-produced plasma

The laser-produced plasma spectra of Cr, Co, and Ni observed between 9 and 14 Å isoelectronic to the iron lines in the wavelength region 10.5–12 Å are measured. Spectral lines belonging to many ionization stages fall in this wavelength region. Classification of most of these lines is given, based on isoelectronic extrapolation with comparison to other works on iron.