The Magellanic Corona as the key to the formation of the Magellanic Stream
The Magellanic Corona as the key to the formation of the Magellanic Stream
复制标题
麦哲伦日冕是麦哲伦流形成的关键
作者：
Scott Lucchini;E. D’Onghia;A. Fox;Chad Bustard;J. Bland;E. Zweibel
银河晕中的主要气体结构是麦哲伦流。这个由中性和电离细丝组成的扩展网络围绕着大麦哲伦星云(LMC)和小麦哲伦星云(SMC)，这两个星系是银河系1-4中质量最大的两个卫星星系。最近的观测表明，大麦哲伦星云和小麦哲伦星云是围绕银河系5的第一个通道，麦哲伦流是由从这两个星云2、6、7剥离出来的气体组成的，其中大部分气体是电离的8、9。尽管长期以来人们一直怀疑潮汐力量10、11和冲压剥离12、13对麦哲伦星流的形成起到了作用，但模型一直未能完全理解其来源3。最近的几项进展--包括发现与麦哲伦星系群14-16有关的矮小星系，确定LMC17的高质量，探测到LMC18，19恒星附近的高度电离气体，以及对宇宙模拟20，21的预测--支持在LMC(麦哲伦日冕)周围存在温暖(约50万开尔文)的电离气体光晕。在这里，我们报告，通过将麦哲伦日冕包括在麦哲伦云坠落到银河系的流体动力学模拟中，我们可以重现麦哲伦流及其前臂。我们的模拟解释了麦哲伦流的丝状结构、空间范围、径向速度梯度和总电离气体质量。我们预测，通过位于LMC附近的背景类星体的紫外光谱中的高电离吸收线，麦哲伦日冕将明确可见。将麦哲伦星云嵌入电离气体的日冕中，可以对气态麦哲伦流进行精确的模拟。
The dominant gaseous structure in the Galactic halo is the Magellanic Stream. This extended network of neutral and ionized filaments surrounds the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC), the two most massive satellite galaxies of the Milky Way1–4. Recent observations indicate that the LMC and SMC are on their first passage around the Galaxy5, that the Magellanic Stream is made up of gas stripped from both clouds2,6,7 and that the majority of this gas is ionized8,9. Although it has long been suspected that tidal forces10,11 and ram-pressure stripping12,13 contributed to the formation of the Magellanic Stream, models have not been able to provide a full understanding of its origins3. Several recent developments—including the discovery of dwarf galaxies associated with the Magellanic group14–16, determination of the high mass of the LMC17, detection of highly ionized gas near stars in the LMC18,19 and predictions of cosmological simulations20,21—support the existence of a halo of warm (roughly 500,000 kelvin) ionized gas around the LMC (the ‘Magellanic Corona’). Here we report that, by including this Magellanic Corona in hydrodynamic simulations of the Magellanic Clouds falling onto the Milky Way, we can reproduce the Magellanic Stream and its leading arm. Our simulations explain the filamentary structure, spatial extent, radial-velocity gradient and total ionized-gas mass of the Magellanic Stream. We predict that the Magellanic Corona will be unambiguously observable via high-ionization absorption lines in the ultraviolet spectra of background quasars lying near the LMC. Embedding the Magellanic Clouds in a corona of ionized gas allows the gaseous Magellanic Stream to be modelled accurately.
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DOI：
10.3847/1538-4357/ab4bdd
发表时间：
2018-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
A. Price-Whelan;D. Nidever;Yumi Choi;E. Schlafly;T. Morton;Sergey E. Koposov;V. Belokurov
通讯作者：
A. Price-Whelan;D. Nidever;Yumi Choi;E. Schlafly;T. Morton;Sergey E. Koposov;V. Belokurov
DOI：
10.3847/1538-4357/aa992a
发表时间：
2017-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
K. Barger;K. Barger;G. Madsen;Andrew J. Fox;B. Wakker;J. Bland-Hawthorn;D. Nidever;L. M. Haffner;L. M. Haffner;Jacqueline Antwi-Danso;Jacqueline Antwi-Danso;Michael Hernandez;N. Lehner;Alex S. Hill;Alex S. Hill;Andrew Curzons;T. Tepper-García
通讯作者：
K. Barger;K. Barger;G. Madsen;Andrew J. Fox;B. Wakker;J. Bland-Hawthorn;D. Nidever;L. M. Haffner;L. M. Haffner;Jacqueline Antwi-Danso;Jacqueline Antwi-Danso;Michael Hernandez;N. Lehner;Alex S. Hill;Alex S. Hill;Andrew Curzons;T. Tepper-García
影响因子：
4.8
作者：
Ethan D Jahn;Laura V. Sales;A. Wetzel;M. Boylan-Kolchin;T K Chan;K. El-Badry;Alexandres Lazar;James S Bullock
通讯作者：
Ethan D Jahn;Laura V. Sales;A. Wetzel;M. Boylan-Kolchin;T K Chan;K. El-Badry;Alexandres Lazar;James S Bullock
影响因子：
4.8
作者：
Zachary Hafen;C. Faucher-Giguère;D. Anglés-Alcázar;J. Stern;D. Keres̆;C. Hummels;C. Esmerian;S. Garrison-Kimmel;K. El-Badry;A. Wetzel;T. K. Chan;P. Hopkins;N. Murray
通讯作者：
Zachary Hafen;C. Faucher-Giguère;D. Anglés-Alcázar;J. Stern;D. Keres̆;C. Hummels;C. Esmerian;S. Garrison-Kimmel;K. El-Badry;A. Wetzel;T. K. Chan;P. Hopkins;N. Murray
影响因子：
4.8
作者：
Erkal, D.;Belokurov, V.;Sohn, S. T.
通讯作者：
Sohn, S. T.