2003ApJS..147..265M

The complete FUSE spectrum of the SMC Wolf-Rayet binary star Sk 108 is presented. The spectrum covers the 905-1186 Å wavelength range at a resolution of about 12,500 and a S/N of 25-50. Detailed component information from higher resolution, UV and optical spectra is used to model the far-UV absorption lines of the ISM in the Galaxy and SMC, and special attention is given to the accuracy of the wavelength scale. Improved FUSE measurements, compared to those previously published, of column densities of Ar, N, P, and H₂and new measurements of O are presented. Relative abundances for P and the four α-particle elements–Ar, O, S, and Si–appear to be at solar values, relative to Zn, in the SMC, even though they may be depleted in the Galaxy. Fe is depleted in both the SMC and the Galaxy, but at higher levels in the Galaxy. This implies that, compared to the Galactic environment, the SMC interstellar clouds either exhibit a lower dust-to-metal ratio or that the dust grains are destroyed (with some remaining dust grains which contain Fe) or that there is an enhancement of α-elements. Furthermore, the overall N abundance appears to be truly deficient in the SMC. In addition, empirical oscillator strengths for a series of Fe II lines are derived, using the predetermined column densities for the Fe II components from GHRS data.