2022ApJS..258...37K

New spectrograms of multiply ionized iron have been recorded and analyzed, targeting the Fe VII spectrum. As a result, several previously unknown spectral lines and energy levels have been identified in this spectrum. These new data have been analyzed together with all previously published laboratory and astrophysical data on this spectrum. The energy levels have been interpreted using parametric calculations with Cowan codes. Radiative transition rates calculated in this work supplemented other previously published calculations in constructing a complete set of recommended transition probabilities. The ionization energy of Fe VII has been redetermined with a fivefold improvement in accuracy. Its new value is 1,007,928(20) cm^–1, corresponding to 124.9671(25) eV.