论文标题
银河系质量的平衡模型受到LMC的偏差
Equilibrium models of the Milky Way mass are biased high by the LMC
论文作者
论文摘要
最近的测量表明，大型麦哲伦云（LMC）的重量可能是银河系的25％。在这项工作中，我们探讨了如此大的卫星如何基于恒星光环或其他示踪剂的平衡建模来影响银河系的质量估计。特别是，我们表明，如果忽略了LMC，则银河系质量被高估了多达50 \％。这种偏见是由于银河系光环郊区的批量运动造成的，至少可以部分地用简单地修改了平衡建模。最后，我们证明LMC对轨道狮子I具有重大影响，该轨道狮子座相对于银河系的速度提高了当天的速度。我们估计，要考虑$ 1.5 \ times10^{11} m_ \ odot $ lmc会将推断的银河系质量降低到$ \ sim10^{12} m_ \ odot $。
Recent measurements suggest that the Large Magellanic Cloud (LMC) may weigh as much as 25\% of the Milky Way. In this work we explore how such a large satellite affects mass estimates of the Milky Way based on equilibrium modelling of the stellar halo or other tracers. In particular, we show that if the LMC is ignored, the Milky Way mass is overestimated by as much as 50\%. This bias is due to the bulk motion in the outskirts of the Galaxy's halo and can be, at least in part, accounted for with a simple modification to the equilibrium modelling. Finally, we show that the LMC has a substantial effect on the orbit Leo I which acts to increase its present day speed relative to the Milky Way. We estimate that accounting for a $1.5\times10^{11} M_\odot$ LMC would lower the inferred Milky Way mass to $\sim10^{12} M_\odot$.
