Sequential Star Formation in the filamentary structures of Planck Galactic cold clump G181.84+0.31
| العنوان: | Sequential Star Formation in the filamentary structures of Planck Galactic cold clump G181.84+0.31 |
|---|---|
| المؤلفون: | Yuefang Wu, Lixia Yuan, Chenlin Zhou, Kee-Tae Kim, Jinghua Yuan, Nario Kuno, Ming Zhu, Tie Liu, Ke Wang, Ken'ichi Tatematsu |
| سنة النشر: | 2019 |
| مصطلحات موضوعية: | 010504 meteorology & atmospheric sciences, Infrared, Young stellar object, FOS: Physical sciences, Astrophysics, engineering.material, 01 natural sciences, Central region, Protein filament, symbols.namesake, 0103 physical sciences, 14. Life underwater, Planck, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, Maple, Star formation, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), engineering, symbols, Substructure |
| الوصف: | We present a multi-wavelength study of the Planck cold clump G181.84+0.31, which is located at the northern end of the extended filamentary structure S242. We have extracted 9 compact dense cores from the SCUBA-2 850 um map, and we have identified 18 young stellar objects (YSOs, 4 Class I and 14 Class II) based on their Spitzer, Wide-field Infrared Survey Explorer (WISE) and Two-Micron All-Sky Survey (2MASS) near- and mid-infrared colours. The dense cores and YSOs are mainly distributed along the filamentary structures of G181.84 and are well traced by HCO$^{+}$(1-0) and N$_{2}$H$^{+}$(1-0) spectral-line emission. We find signatures of sequential star formation activities in G181.84: dense cores and YSOs located in the northern and southern sub-structures are younger than those in the central region. We also detect global velocity gradients of about 0.8$\pm$0.05 km s$^{-1}$pc$^{-1}$ and 1.0$\pm$0.05 km s$^{-1}$pc$^{-1}$ along the northern and southern sub-structures, respectively, and local velocity gradients of 1.2$\pm$0.1 km s$^{-1}$pc$^{-1}$ in the central substructure. These results may be due to the fact that the global collapse of the extended filamentary structure S242 is driven by an edge effect, for which the filament edges collapse first and then further trigger star formation activities inward. We identify three substructures in G181.84 and estimate their critical masses per unit length, which are $\sim$ 101$\pm$15 M$_{\odot}$ pc$^{-1}$, 56$\pm$8 M$_{\odot}$ pc$^{-1}$ and 28$\pm$4 M$_{\odot}$ pc$^{-1}$, respectively. These values are all lower than the observed values ($\sim$ 200 M$_{\odot}$ pc$^{-1}$), suggesting that these sub-structures are gravitationally unstable. 20 pages, 17 figures, article, accepted |
| اللغة: | English |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d3b0a743a43b64a9ce2474320ac91362Test http://arxiv.org/abs/1905.12258Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....d3b0a743a43b64a9ce2474320ac91362 |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |