A multiwavelength observation and investigation of six infrared dark clouds
| العنوان: | A multiwavelength observation and investigation of six infrared dark clouds |
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| المؤلفون: | Chuan-Peng Zhang, Jun-Jie Wang, Guang-Xing Li, Jianjun Zhou, Jinghua Yuan |
| المصدر: | Astronomy & Astrophysics. 598:A76 |
| بيانات النشر: | EDP Sciences, 2017. |
| سنة النشر: | 2017 |
| مصطلحات موضوعية: | Physics, 010308 nuclear & particles physics, Infrared, Milky Way, FOS: Physical sciences, Astronomy and Astrophysics, Context (language use), Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Redshift, Spectral line, Astrophysics - Solar and Stellar Astrophysics, Deuterium, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Spectral energy distribution, Outflow, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR) |
| الوصف: | Context. Infrared dark clouds (IRDCs) are ubiquitous in the Milky Way, yet they play a crucial role in breeding newly-formed stars. Aims. With the aim of further understanding the dynamics, chemistry, and evolution of IRDCs, we carried out multi-wavelength observations on a small sample. Methods. We performed new observations with the IRAM 30 m and CSO 10.4 m telescopes, with tracers ${\rm HCO^+}$, HCN, ${\rm N_2H^+}$, ${\rm C^{18}O}$, DCO$^+$, SiO, and DCN toward six IRDCs G031.97+00.07, G033.69-00.01, G034.43+00.24, G035.39-00.33, G038.95-00.47, and G053.11+00.05. Results. We investigated 44 cores including 37 cores reported in previous work and seven newly-identified cores. Toward the dense cores, we detected 6 DCO$^+$, and 5 DCN lines. Using pixel-by-pixel spectral energy distribution (SED) fits of the $\textit{Herschel}$ 70 to 500 $\mu$m, we obtained dust temperature and column density distributions of the IRDCs. We found that ${\rm N_2H^+}$ emission has a strong correlation with the dust temperature and column density distributions, while ${\rm C^{18}O}$ showed the weakest correlation. It is suggested that ${\rm N_2H^+}$ is indeed a good tracer in very dense conditions, but ${\rm C^{18}O}$ is an unreliable one, as it has a relatively low critical density and is vulnerable to freezing-out onto the surface of cold dust grains. The dynamics within IRDCs are active, with infall, outflow, and collapse; the spectra are abundant especially in deuterium species. Conclusions. We observe many blueshifted and redshifted profiles, respectively, with ${\rm HCO^+}$ and ${\rm C^{18}O}$ toward the same core. This case can be well explained by model "envelope expansion with core collapse (EECC)". Comment: 24 pages, 11 figures, 4 tables. To be published in A&A. The resolutions of the pictures are cut down |
| تدمد: | 1432-0746 0004-6361 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::857e11f2022b23f702a8f1a49c1a9ba7Test https://doi.org/10.1051/0004-6361/201629771Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....857e11f2022b23f702a8f1a49c1a9ba7 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14320746 00046361 |
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