The Bulletin of The Korean Astronomical Society (천문학회보)
- Volume 42 Issue 1
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- Pages.55.1-55.1
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- 2017
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- 1226-2692(pISSN)
On the claimed X-shaped structure in the Milky Way bulge
- Han, Daniel (Center for Galaxy Evolution Research & Department of Astronomy, Yonsei University) ;
- Lee, Young-Wook (Center for Galaxy Evolution Research & Department of Astronomy, Yonsei University)
- Published : 2017.04.10
Abstract
A number of recent studies have claimed that the double red clump observed in the Milky Way bulge is a consequence of an X-shaped structure. In particular, Ness & Lang (2016) report a direct detection of a faint X-shaped structure in the bulge from the residual map of the Wide-Field Infrared Survey Explorer (WISE) image. Here we show, however, that their result is seriously affected by a bulge model subtracted from the original image. When a boxy bulge model is subtracted, instead of a simple exponential bulge model as has been done by Ness & Lang, we find that most of the X-shaped structure in the residuals disappears. Furthermore, even if real, the stellar density in the claimed X-shaped structure appears to be too low to be observed as a strong double red clump at
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