论文标题
银河系的舞蹈和大麦芽云的舞蹈偏转高速级别的星星
Deflection of the hypervelocity stars by the dance of the Milky Way and Large Magellanic Cloud
论文作者
论文摘要
银河中心的超级质量黑洞弹命名的星星将如此迅速地逃脱银河系，以至于它们的轨迹几乎是直线。以前的作品已经表明了这些“超速恒星”如何被银河系的重力场和大麦哲伦云（LMC）偏转，但已忽略了以LMC响应银河系的反射运动来解释银河系的反射运动。这一动议的结果是，今天我们在银河系郊区看到的高速级别的恒星是从银河系中心的几亿年前弹出的。透视图上的这种变化会导致高速恒星轨迹的巨大明显偏转，这与银河系和LMC的重力引起的偏转相同。我们通过以孤立的银河系（带球或扁平的暗物质光环）模拟生产高速恒星的生产，以通过LMC传递的固定银行和银河系对LMC的通过响应。通过Gaia与拟议的Gaianir继任任务的结合，可以进行测量这些挠度所需的适当的运动精度，这些测量值将解锁超速恒星作为银河系形状，LMC的质量以及这两个星系的舞蹈的探针。
Stars slingshotted by the supermassive black hole at the Galactic centre will escape the Milky Way so quickly that their trajectories will be almost straight lines. Previous works have shown how these `hypervelocity stars' are subsequently deflected by the gravitational field of the Milky Way and the Large Magellanic Cloud (LMC), but have neglected to account for the reflex motion of the Milky Way in response to the fly by of the LMC. A consequence of this motion is that the hypervelocity stars we see on the outskirts of the Milky Way today were ejected from where the Milky Way centre was hundreds of millions of years ago. This change in perspective causes large apparent deflections in the trajectories of the hypervelocity stars, which are of the same order as the deflections caused by the gravitational force of the Milky Way and LMC. We quantify these deflections by simulating the production of hypervelocity stars in an isolated Milky Way (with a spherical or flattened dark matter halo), in a fixed-in-place Milky Way with a passing LMC, and in a Milky Way which responds to the passage of the LMC. The proper motion precision necessary to measure these deflections will be possible with the combination of Gaia with the proposed GaiaNIR successor mission, and these measurements will unlock the hypervelocity stars as probes of the shape of the Milky Way, the mass of the LMC, and of the dance of these two galaxies.
