Gaia Early Data Release 3: Structure and properties of the Magellanic Clouds
Gaia Early Data Release 3: Structure and properties of the Magellanic Clouds
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盖亚早期数据发布 3：麦哲伦云的结构和特性
DOI：
10.1051/0004-6361/202039588
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发表时间：
2020-12
影响因子：
6.5
通讯作者：
others
中科院分区：
文献类型：
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作者：
Luri Xavier;Chemin L;Clementini G;Delgado HE;McMillan PJ;Romero-G'omez M;Balbinot E;Castro-Ginard A;Mor R;Ripepi V;others
我们比较了Gaia DR2和Gaia EDR3在麦哲伦星云研究中的性能，并显示了新版本在精度和准确性方面的明显改进。我们还表明，系统仍然存在于数据使得确定LMC的三维几何形状是一个困难的努力；这是盖亚EDR3天体测量的有用性的极限，但使用额外的外部数据可能会变得可行。我们为我们定义的几个子样本导出了LMC的径向和切向速度图和全球剖面。据我们所知，这是第一次推导出银河系外星系盘中多个恒星演化阶段的有序运动和随机运动的两个平面分量，显示了年轻阶段和老阶段之间的差异。我们还分析了空间结构和运动的中心区域，酒吧，和光盘，提供新的见解特征和运动学。最后，我们表明盖亚EDR3数据可以清楚地解决麦哲伦桥问题，我们不仅在全球范围内追踪了从SMC到LMC的恒星密度和速度流，而且还分别追踪了年轻和进化群体。这使我们能够确认桥上的进化种群与年轻种群略有不同。此外，我们能够研究两个麦哲伦星云的外围，在那里我们发现了一些众所周知的特征和新特征的迹象。
We compare the Gaia DR2 and Gaia EDR3 performances in the study of the Magellanic Clouds and show the clear improvements in precision and accuracy in the new release. We also show that the systematics still present in the data make the determination of the 3D geometry of the LMC a difficult endeavour; this is at the very limit of the usefulness of the Gaia EDR3 astrometry, but it may become feasible with the use of additional external data. We derive radial and tangential velocity maps and global profiles for the LMC for the several subsamples we defined. To our knowledge, this is the first time that the two planar components of the ordered and random motions are derived for multiple stellar evolutionary phases in a galactic disc outside the Milky Way, showing the differences between younger and older phases. We also analyse the spatial structure and motions in the central region, the bar, and the disc, providing new insights into features and kinematics. Finally, we show that the Gaia EDR3 data allows clearly resolving the Magellanic Bridge, and we trace the density and velocity flow of the stars from the SMC towards the LMC not only globally, but also separately for young and evolved populations. This allows us to confirm an evolved population in the Bridge that is slightly shift from the younger population. Additionally, we were able to study the outskirts of both Magellanic Clouds, in which we detected some well-known features and indications of new ones.
DOI：
--
发表时间：
2005-06
期刊：
--
影响因子：
--
作者：
C. Robert;G. Casella
通讯作者：
C. Robert;G. Casella