论文标题
NGC 346的内部视线运动学运动学：核心区域的旋转
The internal line-of-sight kinematics of NGC 346: the rotation of the core region
论文作者
论文摘要
我们介绍了年轻的大型小麦哲伦云星形星团NGC 346的中央1x1'的恒星径向速度分析。使用VLT/Muse Integral Field Spectroscopicy与Hubble Space望远镜光度计结合使用，我们提取103个群集成员星星，以测量适合于测量准确的sight of Sight-ight sight sight kinematics。簇成员的恒星在V1 = -3.3（+0.3/-0.2）km/s和V2 = 2.6（+0.1/-0.1）km/s时显示了两个不同的速度组，相对于165.5 +/- 0.2 km/s的全身速度，第三组的系统速度为165.5 +/- 0.2 km/s，并且在V3 = 9.4（+0.1/-0.1 KM）中均为第三组。速度组和恒星的空间位置，或它们在光学颜色磁性图上的位置，这使得恒星速度成为在这样的年轻恒星群中分离单个恒星组件的关键参数，该速度2显示了与omega 2 = -0.4 +/-0.1 1/myr，satermy at sater at sater at sater and sater and sater and sater and sater and sater at sater and sat AT AT AT AT AT AT AT +/---4.9 +-4.9。 NGC 346的形成过程可能通过巨型分子云的分层塌陷而失去了任何自然的运动烙印，并显示出明显的膨胀，这是由于众多ob spection and spection int spection/spection in spection in spection in nimention n. sention n. spection n.最新的《星际编队》剧集发生在大约200万年前。
We present the stellar radial velocity analysis of the central 1x1' of the young massive Small Magellanic Cloud star cluster NGC 346. Using VLT/MUSE integral field spectroscopy in combination with Hubble Space Telescope photometry we extract 103 spectra of cluster member stars suited to measure accurate line-of-sight kinematics. The cluster member stars show two distinct velocity groups at v1 = -3.3 (+0.3/-0.2) km/s and v2 = 2.6 (+0.1/-0.1) km/s, relative to the systemic velocity of 165.5+/-0.2 km/s, and hint for a third group at v3 = 9.4 (+0.1/-0.1 km/s. We show that there is neither a correlation between the velocity groups and the spatial location of the stars, nor their locus on optical color-magnitude diagrams, which makes the stellar velocity a key parameter to separate individual stellar components in such a young star cluster. Velocity group 2 shows clear rotation with Omega2 = -0.4 +/- 0.1 1/Myr, corresponding to -4.9+/-0.7 km/s at radial distance of 10 pc from the center, a possible remnant of the formation process of NGC 346 through the hierarchical collapse of the giant molecular cloud. The ionizing gas has lost any natal kinematic imprint and shows clear expansion, driven by far ultra violet fluxes and stellar winds of the numerous OB stars in the cluster center. The size of this expanding bubble and its expansion velocity of 7.9 km/s is in excellent agreement with the estimate that the latest star formation episode occurred about two million years ago.
