Metallicity and Physical Conditions in the Magellanic Bridge1

Abstract

We present a new analysis of the diffuse gas in the Magellanic Bridge (R.A. >~ 3h) based on HST STIS E140M and FUSE spectra of two early-type stars lying within the Bridge and a QSO behind it. We derive the column densities of the H I (from Lyalpha), N I, O I, Ar I, Si II, S II, and Fe II of the gas in the Bridge. Using the atomic species, we determine the first gas-phase metallicity of the Magellanic Bridge, [Z/H]=-1.02+/-0.07 toward one sight line and -1.7 <0.03-0.1 cm-3). We argue that our findings combined with other recent observational results should motivate new models of the evolution of the SMC-LMC-Galaxy system. Based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer. FUSE is operated for NASA by The Johns Hopkins University under NASA contract NAS5-32985. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.