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Session 61 - New Views of the Magellanic Clouds.
Display session, Wednesday, June 12
Great Hall,

[61.10] The hot gaseous halo of the LMC

B. P. Wakker (Univ. of Wisconsin), Y. -H. Chu, D. Bomans (Univ. of Illinois)

We present a study of the T=1--3\times10^5\,K halo gas in the Large Magellanic Cloud, based on archival and new IUE observations of the C\,IV and Si\,IV absorption lines. From the pattern of detections and non-detections of the high-ionization absorption with respect to the background environments of the stars we derive the following conclusions: For stars near a local source of hot gas, such as a hot star or superbubble, high-ionization absorption is usually seen. It is also seen inside and nearby the supergiant shells. There is weak evidence for the spill-over of hot gas from the supergiant shells. The presence of a continuous hot halo (``corona'') enveloping the LMC is disproven. The data are compatible with the presence of hot gas high above the plane of the LMC, but it must either stay near its place of origin or cool before it travels far. The stars observed with IUE are not optimally distributed to map the halo of the LMC and fully understand its properties. Also, the signal-to-noise ratios of the spectra are low, which prevents a reliable analysis of column densities and velocities. Future observations with HST will be necessary. A better understanding also requires a study of the relationship between the 10^5\,K gas detected in UV absorption lines and the 10^6\,K gas detected in diffuse X-rays. However, additional data will be needed before that is possible.

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