2004ApJS..154..651W

We present an atlas of far-ultraviolet spectra of 21 Wolf-Rayet (WR) stars in the Galaxy and Large and Small Magellanic Clouds, secured with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. The data cover the wavelength range of 912-1190 Å at a spectral resolution of 0.1 Å and span examples of most subtypes in the WN and WC sequences. We discuss the FUV spectral morphology of the different WR sequences, emphasizing the wide range of ions and chemical species exhibiting well-developed P Cygni profiles and emission lines in this wavelength range. For WN stars the relative strengths of C IV/C III, N III/N II, P V/P IV, and Si IV/Si III show a decrease in strength of the high ions from WN3 to WN11 complemented by an increase in the lower ions at later types. The ``super ions'' of O VI and S VI are considered photoionized wind features for WN3-WN6 stars, probably the result of Auger ionization in WN7-WN9 stars, and probably absent at WN10-WN11. The WN5h star Sk 41 in the SMC shows relatively weaker features, which can be ascribed to the effects of a global galaxy metal deficiency. For the WC stars, a similar pattern of wind ionization-linked strengths in the emissions and P Cygni profiles is present, particularly evident in the relative strengths of lines in P V, S IV, Si IV, and Si III. O VI, and S VI features are only seen in the earliest WC subtypes. The high carbon abundance in WC stars is reflected by the presence of strong C IV and C III lines throughout the sequence. We present new estimates of the wind terminal velocities from measurements of saturated absorption components observed in a wide range of I.P. species. Considerable revisions to v_∞for the WN3 and WN5 (SMC) stars in our sample and, in particular for the WN10 and WN11 stars are found. The latter make use of the unique availability of the N II resonance line in the FUSE waveband.