Interstellar Abundances in the Magellanic Clouds. I. GHRS Observations of the Small Magellanic Cloud Star Sk 108

摘要

We present HST GHRS echelle-B and G160M spectra of the Wolf-Rayet binary Sk 108, located in the northeastern part of the main "bar" of the Small Magellanic Cloud. The spectra show interstellar absorption from C I, O I, Si Ⅱ, Si Ⅱ~*, S Ⅱ, P Ⅱ, Cr Ⅱ, Mn Ⅱ, Fe Ⅱ, Ni Ⅱ, and Zn Ⅱ. We find at least 25 interstellar components, which may be grouped via similar kinematics and/or similar relative heavy element abundances into two sets arising in the Galactic disk and halo, plus three sets located in the SMC. The SMC component groups may correspond to large-scale SMC gas complexes identified in H I 21 cm emission surveys. The relative gas phase abundances for Si Ⅱ, Cr Ⅱ, Mn Ⅱ, Fe Ⅱ, Ni Ⅱ, and Zn Ⅱ found for the SMC interstellar components are similar to those found for interstellar clouds in the Galactic halo.