论文标题
测量银河盘对卫星的垂直响应
Measuring the vertical response of the Galactic disc to an infalling satellite
论文作者
论文摘要
使用与卫星相似的银河系的N体模拟，我们定量分析了银河盘对卫星重复影响的垂直响应。我们将银河盘的垂直失真近似为前三个傅立叶方位角术语M = 0、1和2的总和，并在不同的动力学相互作用方面观察它们的演变。在第一次相互作用之后，M = 0项表现为外向环状垂直失真。当卫星的影响更加频繁或一般接近相互作用时，M = 1项（S形经扭曲）是前列的，而在最静态的阶段中，它会缓慢地逆行。 M = 2项通常是序列，并且接近与M = 1项的相互作用。最后，我们发现，可以使用有限的银河盘以类似于真实数据的恒星的瞬时位置和恒星的瞬时位置和速度来以公正的方式恢复圆盘的垂直响应，并且测得的垂直模式速度在mi00 satellite-satellite-satellite相互作用的上下文中具有约束功率。
Using N-body simulations of the Milky Way interacting with a satellite similar to the Sagittarius dwarf galaxy, we quantitatively analyse the vertical response of the Galactic disc to the satellite's repeated impacts. We approximate the vertical distortion of the Galactic disc as the sum of the first three Fourier azimuthal terms m = 0, 1 and 2, and observe their evolution in different dynamical regimes of interaction. After the first interaction, the m=0 term manifests itself as outgoing ring-like vertical distortions. The m=1 term (S-shape warp) is prograde when the impacts of the satellite are more frequent, or in general close to an interaction, whereas it is slowly retrograde in the most quiescent phases. The m=2 term is typically prograde, and close to an interaction it couples with the m=1 term. Finally, we find that the vertical response of the disc can be recovered in an unbiased way using the instantaneous positions and velocities of stars in a limited volume of the Galactic disc, analogous to real data, and that the measured vertical pattern speeds have a constraining power in the context of a Milky Way-satellite interaction.
