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arXiv · 0708.1030

Discovery of a New Dusty B[e] Star in the Small Magellanic Cloud

John P. Wisniewski·Karen S. Bjorkman·Jon E. Bjorkman·Mark Clampin
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Abstract

We present new optical spectroscopic and archival Spitzer IRAC photometric observations of a B-type star in the SMC cluster NGC 346, NGC 346:KWBBe 200. We detect numerous Fe II, [O I], and [Fe II] lines, as well as strong P-Cygni profile H I emission lines in its optical spectrum. The star's near-IR color and optical to IR SED clearly indicate the presence of an infrared excess, consistent with the presence of gas and warm, T ~800 K, circumstellar dust. Based on a crude estimate of the star's luminosity and the observed spectroscopic line profile morphologies, we find that the star is likely to be a B-type supergiant. We suggest that NGC 346:KWBBe 200 is a newly discovered B[e] supergiant star, and represents the fifth such object to be identified in the SMC.

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John P. Wisniewski, Karen S. Bjorkman, Jon E. Bjorkman, Mark Clampin. 2007-08-07. Discovery of a New Dusty B[e] Star in the Small Magellanic Cloud. https://doi.org/10.1086/522330

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