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Mid-Infrared Spectra of Be Stars

S. A. Rinehart·J. R. Houck·J. D. Smith
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Abstract

We present the first medium-resolution ($R\sim 600$) mid-infrared (8-13.3\micron) spectra of 11 Be stars. A large number of lines are observed and identified in these spectra, including, as an example, 39 hydrogen recombination lines in the spectrum of $γ$ Cas. In the majority of our spectra, all of the observed lines are attributable to hydrogen recombination. Two of the sources, $β$ Lyr and MWC 349 also show emission from other species. Both of these objects show evidence of [Ne II] emission, and $β$ Lyr also shows evidence of He I emission. We tabulate the effective line strength and line widths for the observed lines, and briefly discuss the physical implications of the observed line series. We also use a simple model of free-free emission to characterize the disks around these sources.

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S. A. Rinehart, J. R. Houck, J. D. Smith. 1999-10-11. Mid-Infrared Spectra of Be Stars. https://doi.org/10.1086/301119

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