arXiv 0809.52602008-09-30astro-ph

New Circumstellar Dust Creation in V838 Monocerotis

John P. Wisniewski, Mark Clampin, Karen S. Bjorkman, Richard K. Barry, ;

备注：: 4 pages, to appear in the Conference Proceedings Series of the American Institute of Physics, Cool Stars 15
DOI：: 10.1063/1.3099263

英文摘要：

We report high spatial resolution 11.2 and 18.1 micron imaging of the eruptive variable V838 Monocerotis, obtained with Gemini Observatory's Michelle in 2007 March. The 2007 flux density of the unresolved stellar core is roughly 2 times brighter than that observed in 2004. We interpret these data as evidence that V838 Mon has experienced a new circumstellar dust creation event. We also report a gap of spatially extended thermal emission over radial distances of 1860-93000 AU from the central source, which suggests that no prior significant circumstellar dust production events have occurred within the past 900-1500 years.

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