论文标题
四个银河系郊区的动态球形集群：潮流占主导地位
Dynamics in the outskirts of four Milky Way globular clusters: it's the tides that dominate
论文作者
论文摘要
我们介绍了对4个球状聚类郊区的光谱调查的结果 - NGC 1261，NGC 4590，NGC 1904和NGC 1851-涵盖了群集中心1度以内的目标，该目标的目标是2DF/AAOMEGA，上面有2df/Aaomega在盎格鲁 - 奥特拉利亚远程望远镜（Aa aote）和大型（AATESCOPE（AA）上（AATE）和大型（AAT）和竞争（AAT）。我们为单个恒星提取了化学动力信息，从中我们估算了速度分散曲线和每个簇的旋转。将观测值与直接$ n $ body模拟和适当的{\ sc limepy}/{\ sc spes}模型进行比较，以解释结果。在NGC 1851年，检测到的内部旋转与现有文献一致，NGC 1261显示了截断半径以外的旋转信号，可能来自逃脱的恒星。我们发现，NGC 1261，NGC 1851和NGC 1904的观测值和模拟的分散曲线并不降低，因为{\ sc limepy}/{\ sc spes}模型超出了截短半径，其中$ n $ body-body Migulation the $ n $ body-body-body Simulation the useventape the $ n $ body-body Simulations even eved eSc sy eScal saved starpated stars占主导地位； NGC 4590的分散曲线遵循{\ sc limepy}/{\ sc spes}模型的预测，尽管数据没有有效地扩展到截断半径之外。 NGC 1261，NGC 1851和NGC 1904郊区的增加/平面色散曲线被模拟复制。因此，可以通过与银河系的潮汐相互作用来解释所讨论的簇的增加/平坦分散曲线，而无需引入暗物质。
We present the results of a spectroscopic survey of the outskirts of 4 globular clusters -- NGC 1261, NGC 4590, NGC 1904, and NGC 1851 -- covering targets within 1 degree from the cluster centres, with 2dF/AAOmega on the Anglo-Australian Telescope (AAT) and FLAMES on the Very Large Telescope (VLT). We extracted chemo-dynamical information for individual stars, from which we estimated the velocity dispersion profile and the rotation of each cluster. The observations are compared to direct $N$-body simulations and appropriate {\sc limepy}/{\sc spes} models for each cluster to interpret the results. In NGC 1851, the detected internal rotation agrees with existing literature, and NGC 1261 shows some rotation signal beyond the truncation radius, likely coming from the escaped stars. We find that the dispersion profiles for both the observations and the simulations for NGC 1261, NGC 1851, and NGC 1904 do not decrease as the {\sc limepy}/{\sc spes} models predict beyond the truncation radius, where the $N$-body simulations show that escaped stars dominate; the dispersion profile of NGC 4590 follows the predictions of the {\sc limepy}/{\sc spes} models, though the data do not effectively extend beyond the truncation radius. The increasing/flat dispersion profiles in the outskirts of NGC 1261, NGC 1851 and NGC 1904, are reproduced by the simulations. Hence, the increasing/flat dispersion profiles of the clusters in question can be explained by the tidal interaction with the Galaxy without introducing dark matter.
