While most moving groups are young and nearby, a small number have been identified in the Galactic halo. Understanding the origin and evolution of these groups is an important piece of reconstructing the formation history of the halo. Here we report on our analysis of three putative halo moving groups: G03-37, G18-39, and G21-22. Based on Gaia EDR3 data, the stars associated with each group show some scatter in velocity (e.g., Toomre diagram) and integrals of motion (energy, angular momentum) spaces, counter to expectations of moving-group stars. We choose the best candidate of the three groups, G21-22, for follow-up chemical analysis based on high-resolution spectroscopy of six presumptive members. Using a new Python code that uses a Bayesian method to self-consistently propagate uncertainties from stellar atmosphere solutions in calculating individual abundances and spectral synthesis, we derive the abundances of α- (Mg, Si, Ca, Ti), Fe-peak (Cr, Sc, Mn, Fe, Ni), odd-Z (Na, Al, V), and neutron-capture (Ba, Eu) elements for each star. We find that the G21-22 stars are not chemically homogeneous. Based on the kinematic analysis for all three groups and the chemical analysis for G21-22, we conclude the three are not genuine moving groups. The case for G21-22 demonstrates the benefit of combining kinematic and chemical information in identifying conatal populations when either alone may be insufficient. Comparing the integrals of motion and velocities of the six G21-22 stars with those of known structures in the halo, we tentatively associate them with the Gaia-Enceladus accretion event.

虽然大多数移动的团体都很年轻且就在附近，但在银河光环中已经确定了一小部分。了解这些群体的起源和演化是重建光晕形成历史的重要部分。在这里，我们报告了我们对三个假定的光晕移动群的分析：G03-37、G18-39 和 G21-22。根据盖亚 EDR3 数据，与每组相关的恒星在速度（例如 Toomre 图）和运动积分（能量、角动量）空间中显示出一些散射，这与移动群恒星的预期相反。我们选择三组中的最佳候选者 G21-22，进行基于六名推定成员的高分辨率光谱的后续化学分析。α -（Mg、Si、Ca、Ti）、Fe 峰（Cr、Sc、Mn、Fe、Ni）、奇数Z（Na、Al、V）和中子俘获（Ba、Eu）元素星星。我们发现 G21-22 恒星在化学上不是均质的。基于所有三个群的运动学分析和 G21-22 的化学分析，我们得出结论，这三个群不是真正的运动群。G21-22 的案例表明，当单独使用运动学和化学信息时，结合运动学和化学信息在识别同生人群中的任何一个都可能是不够的。将六颗 G21-22 恒星的运动和速度积分与晕中已知结构的积分进行比较，我们暂时将它们与盖亚-土卫二吸积事件联系起来。