论文标题
使用卫星星系适当运动的大规模仙女座星系的证据
Evidence for a Massive Andromeda Galaxy Using Satellite Galaxy Proper Motions
论文作者
论文摘要
我们使用四个卫星星系（M33，NGC 185，NGC 147，IC 10）的轨道角动量（M31）提出了新的质量估计值（M31）。我们推断出M31的两个质量：$ M _ {\ rm vir} = 2.85^{+1.47} _ { - 0.77} \ times10^{12} \，M _ {\ odot} $使用卫星Galaxy Pase Space使用基于HST的M31适当的Motions和$ M _ _ { VIR} = 3.02^{+1.30} _ { - 0.69} \ times10^{12} \，m _ {\ odot} $，使用具有基于HST+GAIA的M31的加权平均值得出的相位信息。与以前的质量估计相比，使用类似方法的质量估计，我们新的M31质量估计值的精度提高了两倍，仅具有一个卫星星系，并将我们的结果置于最近文献中最高的Precision M31估计中。此外，我们的结果与最近修订的本地群体总质量（LG），具有出色的质量质量关系以及M31及其整个卫星种群的运动学数据一致。 M31质量$> 2.5 \ times 10^{12} \，m _ {\ odot} $可能对我们对LG动力学的理解，M31的合并和积聚历史以及我们对宇宙学环境中对LG星系的理解具有重大影响。
We present new mass estimates for Andromeda (M31) using the orbital angular momenta of four satellite galaxies (M33, NGC 185, NGC 147, IC 10) derived from existing proper motions, distances, and line-of-sight velocities. We infer two masses for M31: $M_{\rm vir}= 2.85^{+1.47}_{-0.77}\times10^{12}\, M_{\odot}$ using satellite galaxy phase space information derived with HST-based M31 proper motions and $M_{\rm vir}=3.02^{+1.30}_{-0.69}\times10^{12}\, M_{\odot}$ using phase space information derived with the weighted average of HST+Gaia-based M31 proper motions. The precision of our new M31 mass estimates (23-50%) improves by a factor of two compared to previous mass estimates using a similar methodology with just one satellite galaxy and places our results amongst the highest precision M31 estimates in recent literature. Furthermore, our results are consistent with recently revised estimates for the total mass of the Local Group (LG), with the stellar mass--halo mass relation, and with observed kinematic data for both M31 and its entire population of satellites. An M31 mass $> 2.5 \times 10^{12}\, M_{\odot}$ could have major implications for our understanding of LG dynamics, M31's merger and accretion history, and our understanding of LG galaxies in a cosmological context.
