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arXiv · 1603.03296

FGK 22 $\mu$m Excess Stars in LAMOST DR2 Stellar Catalog

Chao-Jian Wu·Hong Wu·Kang Liu·Tan-Da Li·Ming Yang·Man I Lam·Fan Yang·Yue Wu·Yong Zhang·Yonghui Hou·Guangwei Li
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Abstract

Since the release of LAMOST (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope) catalog, we have the opportunity to use the LAMOST DR2 stellar catalog and \emph{WISE All-sky catalog} to search for 22 $\mu$m excess candidates. In this paper, we present 10 FGK candidates which show an excess in the infrared (IR) at 22 $\mu$m. The ten sources are all the newly identified 22 $\mu$m excess candidates. Of these 10 stars, 5 stars are F type and 5 stars are G type. The criterion for selecting candidates is $K_s-[22]_{\mu m}\geq0.387$. In addition, we present the spectral energy distributions (SEDs) covering wavelength from optical to mid-infrared band. Most of them show an obvious excess from 12 $\mu$m band and three candidates even show excess from 3.4 $\mu$m. To characterize the amount of dust, we also estimate the fractional luminosity of ten 22 $\mu$m excess candidates.

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Chao-Jian Wu, Hong Wu, Kang Liu, Tan-Da Li, Ming Yang, Man I Lam, Fan Yang, Yue Wu, Yong Zhang, Yonghui Hou, Guangwei Li. 2016-03-10. FGK 22 $\mu$m Excess Stars in LAMOST DR2 Stellar Catalog. https://doi.org/10.1088/1674-4527/16/7/102

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