ar X iv : a st ro - p h / 01 09 22 4 v 1 1 4 Se p 20 01 Interstellar O vi in the Large Magellanic Cloud
نویسنده
چکیده
I summarize Far Ultraviolet Spectroscopic Explorer (FUSE) observations of interstellar O vi absorption towards 12 early-type stars in the Large Magellanic Cloud (LMC), the closest disk galaxy to the Milky Way. LMC O vi is seen towards all 12 stars with properties (average column densities, kinematics) very similar to those of the Milky Way halo, even though O/H in the LMC is lower by a factor of ∼ 2.5. Sight lines projected onto known LMC superbubbles show little enhancement in O vi column density compared to sight lines towards quiescent regions of the LMC. The O vi absorption is displaced by ∼ −30 km s from the corresponding low-ionization absorption associated with the bulk of the LMC gas. The LMC O vi most likely arises in a vertically-extended distribution, and I discuss the measurements in the context of a halo composed of radiatively-cooling hot gas. In this case, the mass-flow rate from one side of the LMC disk is of the order Ṁ ∼ 1 M⊙ yr .
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