论文标题
附近的年轻恒星移动组的低质量成员来自Gaia Edr3
Low-mass members of nearby young stellar moving groups from Gaia EDR3
论文作者
论文摘要
Gaia Edr3为附近物体提供了大大改进的运动学，包括附近的年轻恒星移动组（Nymgs）的成员。在这项研究中，我们旨在鉴定Gaia EDR3中的低质量Nymg成员（M0至中期的光谱类型）。我们利用先前研究中开发的贝叶斯成员概率计算方案计算了空间成员概率。我们主要根据颜色刻度图的位置评估了恒星青年。结合了空间成员评估和青年评估，我们确定了约2900个低质量NYMG候选会员，包括〜700名先前声称的成员。在约2200名新候选人的一组中，根据NUV亮度，约有550名年轻。我们在ANU 2.3-m望远镜上使用Wifes进行的试验光谱研究观察到了78个候选人，其中79％被确认为成员。使用我们的新成员样本，我们估计了Beta-Pictoris移动组的等级年龄。平均年龄（〜10 Myr）是最近估计年龄的一半，这表明beta-pictoris移动群体的年龄很小，或者是当代等速线中的不准确性。作为这项研究的主要结果，我们提供了新确认和候选低质量NYMG成员的清单。
Gaia EDR3 offers greatly improved kinematics for nearby objects, including members of nearby young stellar moving groups (NYMGs). In this study, we aim to identify low-mass NYMG members (spectral types of M0 to mid-L) in Gaia EDR3. We calculated spatio-kinematic membership probabilities utilising a Bayesian membership probability calculation scheme developed in our previous study. We evaluated stellar youth primarily based on colour-magnitude diagram positions. Combining spatio-kinematic membership assessment and youth evaluation, we identified ~2900 low-mass NYMG candidate members including ~700 previously claimed members. In the set of ~2200 new candidate members, ~550 appear to be young based on NUV brightness. Our pilot spectroscopic study with WiFeS on the ANU 2.3-m telescope observed 78 candidates, with 79 per cent confirmed as members. Using our new member sample, we estimated an isochronal age of the beta-Pictoris Moving Group. The mean age (~10 Myr), which is around half the age of recent estimates, suggests either a truly younger age of the beta-Pictoris Moving Group or inaccuracies in contemporary isochrones. As the main results of this study, we provide lists of newly confirmed and candidate low-mass NYMG members.
