The CO-dark molecular gas mass in 30 Doradus
The CO-dark molecular gas mass in 30 Doradus
复制标题
剑鱼座 30 中的 CO 暗分子气体质量
DOI：
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
H. Zinnecker
中科院分区：
文献类型：
--
作者：
M. Chevance;S. Madden;C. Fischer;W. Vacca;V. Lebouteiller;D. Fadda;F. Galliano;R. Indebetouw;R. Indebetouw;J. Kruijssen;M.;A. Poglitsch;F. Polles;D. Cormier;S. Hony;C. Iserlohe;A. Krabbe;M. Meixner;E. Sabbi;H. Zinnecker
要确定星系中气体转化为恒星的效率，需要准确地确定分子气体质量的总储量。然而，尽管是宇宙中最丰富的分子，但通过直接观测来检测H$_2$具有挑战性，并且必须使用间接方法来估计总分子气藏。这些通常是基于示踪剂（如CO或尘埃）的标度关系，并且通常在银河系中校准。然而，越来越多的证据表明这些缩放关系依赖于环境。特别地，通常使用的CO到H2的转换因子（X CO）预计在贫金属和/或强UV照射的环境中更高。我们使用新的索菲亚/FIFI-LS观测远红外精细结构线的电离和中性气体和Meudon光解区域模型来约束的物理性质和结构的气体在大麦哲伦星云的30剑鱼座的大质量恒星形成区域，并确定空间分辨分布的总水库的分子气体在附近的年轻的大质量集群R136。我们将此值与从地面CO观测和尘埃估计推断的分子气体质量进行比较，以量化这种极端环境对常用分子气体示踪剂的影响。我们发现，强大的辐射场结合周围气体的半太阳金属量是负责一个大的水库的“CO暗”分子气体，留下了很大一部分的总H$_2$气体（> 75%）未被检测到时，采用标准的X$_{\rmCO}$因子在这个巨大的恒星形成区域。
Determining the efficiency with which gas is converted into stars in galaxies requires an accurate determination of the total reservoir of molecular gas mass. However, despite being the most abundant molecule in the Universe, H$_2$ is challenging to detect through direct observations and indirect methods have to be used to estimate the total molecular gas reservoir. These are often based on scaling relations from tracers such as CO or dust, and are generally calibrated in the Milky Way. Yet, evidence that these scaling relations are environmentally dependent is growing. In particular, the commonly used CO-to-H$_2$ conversion factor (X$_{\rm CO}$) is expected to be higher in metal-poor and/or strongly UV-irradiated environments. We use new SOFIA/FIFI-LS observations of far-infrared fine structure lines from the ionised and neutral gas and the Meudon photodissociation region model to constrain the physical properties and the structure of the gas in the massive star-forming region of 30 Doradus in the Large Magellanic Cloud, and determine the spatially resolved distribution of the total reservoir of molecular gas in the proximity of the young massive cluster R136. We compare this value with the molecular gas mass inferred from ground-based CO observations and dust-based estimates to quantify the impact of this extreme environment on commonly used tracers of the molecular gas. We find that the strong radiation field combined with the half-solar metallicity of the surrounding gas are responsible for a large reservoir of "CO-dark" molecular gas, leaving a large fraction of the total H$_2$ gas (> 75%) undetected when adopting a standard X$_{\rm CO}$ factor in this massive star-forming region.
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影响因子：
6.5
作者：
D. Cormier;N. Abel;S. Hony;V. Lebouteiller;S. Madden;F. Polles;F. Galliano;I. D. Looze;M. Galametz;A. Lambert-Huyghe
通讯作者：
D. Cormier;N. Abel;S. Hony;V. Lebouteiller;S. Madden;F. Polles;F. Galliano;I. D. Looze;M. Galametz;A. Lambert-Huyghe
DOI：
10.1088/2041-8205/730/2/l13
发表时间：
2011-02
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
F. Bigiel;A. Leroy;F. Walter;E. Brinks;W. D. Blok;C. Kramer;H. Rix;A. Schruba;K. Schuster;A. Usero;H. Wiesemeyer
通讯作者：
F. Bigiel;A. Leroy;F. Walter;E. Brinks;W. D. Blok;C. Kramer;H. Rix;A. Schruba;K. Schuster;A. Usero;H. Wiesemeyer
DOI：
10.1088/0004-6256/136/3/919
发表时间：
2005-06
期刊：
The Astronomical Journal
影响因子：
--
作者：
M. Meixner;K. Gordon;R. Indebetouw;J. Hora;B. Whitney;R. Blum;W. Reach;J. Bernard;M. Meade;B. Babler;C. Engelbracht;B. For;K. Misselt;U. Vijh;C. Leitherer;M. Cohen;E. Churchwell;F. Boulanger;J. Frogel;Y. Fukui;J. Gallagher;V. Gorjian;J. Harris;D. Kelly;A. Kawamura;Soyoung Kim;W. Latter;S. Madden;Ciska Markwick-Kemper;A. Mizuno;N. Mizuno;J. Mould;A. Nota;M. Oey;K. Olsen;T. Onishi;R. Paladini;N. Panagia;P. Pérez-González;H. Shibai;Sato Shuji;Linda J. Smith;L. Staveley-Smith;A. Tielens;T. Ueta;S. V. Dyk;K. Volk;M. Werner;D. Zaritsky
通讯作者：
M. Meixner;K. Gordon;R. Indebetouw;J. Hora;B. Whitney;R. Blum;W. Reach;J. Bernard;M. Meade;B. Babler;C. Engelbracht;B. For;K. Misselt;U. Vijh;C. Leitherer;M. Cohen;E. Churchwell;F. Boulanger;J. Frogel;Y. Fukui;J. Gallagher;V. Gorjian;J. Harris;D. Kelly;A. Kawamura;Soyoung Kim;W. Latter;S. Madden;Ciska Markwick-Kemper;A. Mizuno;N. Mizuno;J. Mould;A. Nota;M. Oey;K. Olsen;T. Onishi;R. Paladini;N. Panagia;P. Pérez-González;H. Shibai;Sato Shuji;Linda J. Smith;L. Staveley-Smith;A. Tielens;T. Ueta;S. V. Dyk;K. Volk;M. Werner;D. Zaritsky
30 DORADUS 电离气体中的物理条件
DOI：
10.1088/0004-637x/694/1/84
发表时间：
2009
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Indebetouw R
通讯作者：
Indebetouw R