We use a particle tagging technique to dynamically populate the N-body Via Lactea II high-resolution simulation with stars. The method is calibrated using the observed luminosity function of Milky Way (MW) satellites and the concentration of their stellar populations, and self-consistently follows the accretion and disruption of progenitor dwarfs and the buildup of the stellar halo in a cosmological "live host." Simple prescriptions for assigning stellar populations to collisionless particles are able to reproduce many properties of the observed MW halo and its surviving dwarf satellites, like velocity dispersions, sizes, brightness profiles, metallicities, and spatial distribution. Our model predicts the existence of approximately 1850 subhalos harboring "extremely faint" satellites (with mass-to-light ratios 5 × 103) lying beyond the Sloan Digital Sky Survey detection threshold. Of these, about 20 are "first galaxies," i.e., satellites that formed a stellar mass above 10 M ☉ before redshift 9. The 10 most luminous satellites (L 106 L ☉) in the simulation are hosted by subhalos with peak circular velocities today in the range V max = 10-40 km s–1 that have shed between 80% and 99% of their dark mass after being accreted at redshifts 1.7 z 4.6. The satellite maximum circular velocity V max and stellar line-of-sight velocity dispersion σlos today follow the relation V max = 2.2σlos. We apply a standard mass estimation algorithm based on Jeans modeling of the line-of-sight velocity dispersion profiles to the simulated dwarf spheroidals and test the accuracy of this technique. The inner (within 300?pc) mass-luminosity relation for currently detectable satellites is nearly flat in our model, in qualitative agreement with the "common mass scale" found in MW dwarfs. We do, however, predict a weak, but significant positive correlation for these objects: M 300∝L 0.088 ± 0.024.
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机译：我们使用粒子标记技术通过星动态通过Lactea II高分辨率模拟动态填充N体。该方法是使用银河系（MW）卫星的观测光度函数及其恒星群的浓度进行校准的，并且自始至终地跟随着原始矮星的增生和破坏以及宇宙学“活体”中恒星晕的形成。 ”将恒星种群分配给无碰撞粒子的简单处方能够重现观测到的兆瓦晕及其尚存的矮卫星的许多特性，例如速度色散，大小，亮度分布，金属性和空间分布。我们的模型预测，存在着超过1850个亚晕，其中包含“斯洛恩数字天空调查”检测阈值之外的“极其微弱”的卫星（质光比> 5×103）。其中，大约有20个是“第一星系”，即在红移9之前形成大于10 M a的恒星质量的卫星。模拟中的10个最发光的卫星（L> 106 L☉）由具有峰值圆速度的次晕托管如今，在V max = 10-40 km s-1的范围内，在以1.7 展开▼
