Seventh spectrum of tungsten (W vii); resonance lines of Hf v

Observations of W vii were carried out in the spectral range 100 to 2000 \AA{} utilizing normal- and grazing-incidence spectrographs. The light source was a sliding spark operated at peak currents of 1000 to 3000 A. Eighty-five energy levels of $4{f}^{13}\mathrm{nl}$ and $5{p}^{5}\mathrm{nl}$ configurations were deduced for $nl=5d, 6s, 6p, 6d, \mathrm{and} 7s$. These are based on the classification of 310 lines in the range 130 to 1436 \AA{}. Calculations of all observed configurations were carried out with configuration interaction (CI) for the purpose of fitting radial integrals and confirming the analysis. The strong CI between ${p}^{5}\mathrm{nl}$ and ${f}^{13}\mathrm{nl}$ configurations where $nl=5d, 6p, 6d$ provided well-defined CI integrals in good agreement with Hartree-Fock values. A value of 984 100 \ifmmode\pm\else\textpm\fi{} 500 ${\mathrm{cm}}^{\ensuremath{-}1}$ was derived for the ionization energy from the $4{f}^{13}\mathrm{ns}$ series. The resonance lines of Hf v for $5{p}^{6}\ensuremath{-}5{p}^{5}5d$, $6s$ are given. A revised value for the the ionization energy of W vi is given.