Gas in and toward the Magellanic Clouds

The authors present Ca II K absorption spectra, at resolutions of 8 - 17 km s-1, of 48 early-type supergiants in the Large and Small Magellanic Clouds. These data are used to study the possible fragmentary nature of the Clouds (particularly the SMC); and the distance to the gas responsible for the absorption lines at 60 and 120 km s-1 (LSR) seen in UV spectra of Magellanic Cloud stars. In both Clouds, velocity components in the neutral hydrogen distribution lie at different distances along the line of sight. There is also lower column density material, similar to the 60 and 120 km s-1 features, which can be demonstrated to lie within the Clouds. Good agreement is found between the spread in radial velocity shown in absorbing material and the radial velocity spread predicted by Murai and Fujimoto's dynamical model of the formation of the Magellanic Stream by tidal stripping.