Deep Near-infrared Imaging of an Embedded Cluster in the Extreme Outer Galaxy: Census of Supernovae Triggered Star Formation
نویسندگان
چکیده
While conducting a near-infrared (NIR) survey of “Digel Clouds”, which are thought to be located in the extreme outer Galaxy (EOG), Kobayashi & Tokunaga found star formation activity in “Cloud 2”, a giant molecular cloud at the Galactic radius of ∼ 20 kpc. Additional infrared imaging showed two embedded young clusters at the densest regions of the molecular cloud. Because the molecular cloud is located in the vicinity of a supernova remnant (SNR) HI shell, GSH 138-01-94, it was suggested that the star formation activity in Cloud 2 was
منابع مشابه
Star Formation in the Most Distant Molecular Cloud in the Extreme Outer Galaxy: a Laboratory of Star Formation in an Early Epoch of the Galaxy’s Formation
We report the discovery of active star formation in Digel’s Cloud 2, which is one of the most distant giant molecular clouds known in the extreme outer Galaxy (EOG). At the probable Galactic radius of ∼20 kpc, Cloud 2 has a quite different environment from that in the solar neighborhood, including lower metallicity, much lower gas density, and small or no perturbation from spiral arms. With new...
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