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arXiv · 2211.10063

WISE Green Objects (WGOs): the massive star candidates in the whole Galactic Plane ($\mid b \mid <2^\circ$)

Chang Zhang·Guo-Yin Zhang·Jin-Zeng Li·Jing-Hua Yuan
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Abstract

Massive young stellar objects (MYSOs) play a crucial role in star formation. Given that MYSOs were previously identified based on the extended structure and the observational data for them is limited, screening the Wide-field Infrared Survey Explorer (WISE) objects showing green features (for the common coding of the 4.6 $\mu$m band as green channel in three-color composite WISE images) will yield more MYSO candidates. Using WISE images in the whole Galactic Plane ($ 0^\circ 60^\circ$. Matching results with various masers show that those three groups of WGOs are at different evolutionary stages. After cross-matching WGOs with published YSO survey catalogs, we infer that $\sim$50% of WGOs are samples of newly discovered YSOs. In addition, 1260 WGOs are associated with Hi-GAL sources, according to physical parameters estimated by spectral energy distribution fitting, of which 231 are classified as robust MYSOs and 172 as candidate MYSOs.

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Chang Zhang, Guo-Yin Zhang, Jin-Zeng Li, Jing-Hua Yuan. 2022-11-18. WISE Green Objects (WGOs): the massive star candidates in the whole Galactic Plane ($\mid b \mid <2^\circ$). https://doi.org/10.3847/1538-4365/aca325

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