KMS of Xinjiang Astronomical Observatory, CAS
| Catching the Birth of a Dark Molecular Cloud for the First Time | |
Zuo, Pei1,2,3; Li, Di1,2,3; Peek, J. E. G.4,5; Chang, Qiang6 ; Zhang, Xia6; Chapman, Nicholas7; Goldsmith, Paul F.8; Zhang, Zhi-Yu9,10
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| 2018-11-01 | |
| Source Publication | ASTROPHYSICAL JOURNAL
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| ISSN | 0004-637X |
| Volume | 867Issue:1Pages:13 |
| Contribution Rank | 6 |
| Abstract | The majority of hydrogen in the interstellar medium (ISM) is in atomic form. The transition from atoms to molecules and, in particular, the formation of the H-2 molecule, is a key step in cosmic structure formation en route to stars. Quantifying H-2 formation in space is difficult, due to the confusion in the emission of atomic hydrogen (H I) and the lack of a H-2 signal from the cold ISM. Here we present the discovery of a rare, isolated dark cloud currently undergoing H-2 formation, as evidenced by a prominent "ring" of H I. self-absorption. Through a combined analysis of H I. narrow self-absorption, CO emission, dust emission, and extinction, we directly measured, for the first time, the [H I]/[H-2] abundance varying from 2% to 0.2%, within one region. These measured H I. abundances are orders of magnitude higher than usually assumed initial conditions for protoplanetary disk models. None of the fast cloud formation model could produce such low atomic hydrogen abundance. We derived a cloud formation timescale of similar to 6 x 10(6) years, consistent with the global Galactic star formation rate, and favoring the classical star formation picture over fast star formation models. Our measurements also help constrain the H-2 formation rate, under various ISM conditions. |
| Keyword | ISM: atoms ISM: clouds ISM: molecules |
| DOI | 10.3847/1538-4357/aad571 |
| Indexed By | SCI |
| Language | 英语 |
| WOS Keyword | NARROW SELF-ABSORPTION ; TRANSLUCENT SIGHT LINES ; COLD ATOMIC-HYDROGEN ; STAR-FORMATION ; GALAXY ; ABUNDANCES ; CARBON ; CORES |
| Funding Project | National Key R&D Program of China[2017YFA0402600] ; National Natural Science Foundation of China[11690024] ; National Natural Science Foundation of China[11725313] ; International Partnership Program of Chinese Academy of Sciences[114A11KYSB20160008] ; National Science Foundation[AST-1100968] ; CAS Interdisciplinary Innovation Team program ; ERC[321302] |
| WOS Research Area | Astronomy & Astrophysics |
| WOS Subject | Astronomy & Astrophysics |
| WOS ID | WOS:000448448800013 |
| Publisher | IOP PUBLISHING LTD |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://ir.xao.ac.cn/handle/45760611-7/2214 |
| Collection | 中国科学院新疆天文台 |
| Corresponding Author | Zuo, Pei |
| Affiliation | 1.Chinese Acad Sci, Natl Astron Observ, Datun Rd, Beijing 100101, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Chinese Acad Sci, CAS Key Lab FAST, NAOC, Beijing 100101, Peoples R China 4.Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA 5.Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA 6.Chinese Acad Sci, Xinjiang Astron Observ, 150 Sci 1 St, Urumqi 830011, Xinjiang, Peoples R China 7.Northwestern Univ, CIERA, 2145 Sheridan Rd, Evanston, IL 60208 USA 8.CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA 9.Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland 10.ESO, Karl Schwarzschild Str 2, D-85748 Munich, Germany |
| Recommended Citation GB/T 7714 | Zuo, Pei,Li, Di,Peek, J. E. G.,et al. Catching the Birth of a Dark Molecular Cloud for the First Time[J]. ASTROPHYSICAL JOURNAL,2018,867(1):13. |
| APA | Zuo, Pei.,Li, Di.,Peek, J. E. G..,Chang, Qiang.,Zhang, Xia.,...&Zhang, Zhi-Yu.(2018).Catching the Birth of a Dark Molecular Cloud for the First Time.ASTROPHYSICAL JOURNAL,867(1),13. |
| MLA | Zuo, Pei,et al."Catching the Birth of a Dark Molecular Cloud for the First Time".ASTROPHYSICAL JOURNAL 867.1(2018):13. |
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| Zuo-2018-Catching th（514KB） | 期刊论文 | 出版稿 | 开放获取 | CC BY-NC-SA | View Application Full Text | |
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