Diffuse 18µ Emission around TYC 3159-6-1 Discovered by the AKARI MIR All-Sky Survey
Abstract
We report on observations of the mysterious object TYC 3159-6-1 located toward the Cygnus X region. It shows interesting characteristics in the AKARI mid-infrared All-Sky Survey. The central star is clearly detected as a point source at 9μ, while no point-like source, but a large shell-like structure is seen around the source at 18μ. The optical spectrum indicates the presence of the weak Hα emission on the red smooth continuum, whereas the mid-infrared N-band spectrum shows neither excess emission nor significant silicate absorption. Interferometric continuum observations at 104GHz do not show any appreciable peak at the position of the star. On the basis of these observations, we investigate three possibilities of concerning the nature of TYC 3159-6-1: a nearby young stellar object, a heavily extincted high-mass star, and an asymptotic giant branch (AGB) star with a detached shell. We conclude that none of these cases can account for the observations consistently, and the nature of TYC 3159-6-1 remains a mystery.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- February 2009
- DOI:
- 10.1093/pasj/61.2.291
- Bibcode:
- 2009PASJ...61..291T
- Keywords:
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- infrared: ISM;
- ISM: clouds;
- stars: individual (TYC 3159-6-1)