标题： 关于银河晕的所谓对偶性 显示英文标题

标题： On the alleged duality of the Galactic halo

摘要： 我们基于Carollo等人(2007, 2010)的SDSS/SEGUE数据研究了银河晕的运动学。我们发现他们关于反向旋转晕的主张是距离估计中显著偏差（约50%）的结果：所谓的反向旋转晕成分被识别为距离高估的尾部。强烈的高估也导致垂直速度分量的提升，这解释了这些物体被声称达到的高海拔。误差最严重的是金属含量最低的恒星，这解释了人工成分的贫金属特性。我们对数据的评估导致了速度椭球的重新估计，并未提供任何可靠的反向旋转晕成分的证据。如果存在反向旋转晕，它必须比Carollo等人所声称的弱得多。 显示英文摘要

摘要： We examine the kinematics of the Galactic halo based on SDSS/SEGUE data by Carollo et al. (2007, 2010). We find that their claims of a counter-rotating halo are the result of substantial biases in distance estimates (of order 50%): the claimed counter-rotating halo component is identified as the tail of distance overestimates. The strong overestimates also result in a lift in the vertical velocity component, which explains the large altitudes those objects were claimed to reach. Errors are worst for the lowest metallicity stars, which explains the metal-poor nature of the artificial component. Our evaluation of the data leads to a revision of the estimated velocity ellipsoids and does not yield any reliable evidence for a counterrotating halo component. If a counterrotating halo exists it must be far weaker than claimed by Carollo et al.