In the Gaia era, the majority of stars in the Solar neighbourhood have parallaxes and proper motions precisely determined while spectroscopic age indicators are still missing for a large fraction of low-mass young stars. In this work, we select 756 overluminous late K and early M young star candidates in the southern sky and observe them over 64 nights with the ANU 2.3-m Telescope at Siding Spring Observatory using the Echelle (R = 24 000) and Wide Field spectrographs (WiFeS, R = 3000–7000). Our selection is kinematically unbiased to minimize the preference against low-mass members of stellar associations that dissipate first and to include potential members of diffuse components. We provide measurements of Hα and calcium H&K emission, as well as of Li i 6708 Å in absorption. This enables identification of stars as young as 10–30 Myr – a typical age range for stellar associations. We report on 346 stars showing detectable lithium absorption, 318 of which are not included in existing catalogues of young stars. We also report 125 additional stars in our sample presenting signs of stellar activity indicating youth but with no detectable lithium. Radial velocities are determined for WiFeS spectra with a precision of 3.2 km s−1 and 1.5 km s−1 for the Echelle sample.

中文翻译：

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光谱证实盖亚选择的 318 颗新年轻恒星样本，在 ∼200 pc 范围内

在盖亚时代，太阳附近的大多数恒星都有精确确定的视差和自行，而大部分低质量年轻恒星的光谱年龄指标仍然缺失。在这项工作中，我们在南部天空中选择了 756 颗过亮的晚 K 和早 M 年轻恒星候选者，并使用 Echelle (R = 24 000) 和广角光谱仪在 Siding Spring 天文台使用 ANU 2.3-m 望远镜在 64 个晚上观察它们（WiFeS，R = 3000–7000）。我们的选择在运动学上是无偏的，以尽量减少对首先消散的恒星协会的低质量成员的偏好，并包括弥散成分的潜在成员。我们提供了对 Hα 和钙 H&K 发射以及 Li i 6708 Å 吸收的测量。这可以识别出年龄在 10-30 Myr 之间的恒星——这是恒星关联的典型年龄范围。我们报告了 346 颗显示可检测到锂吸收的恒星，其中 318 颗未包含在现有的年轻恒星目录中。我们还在我们的样本中报告了 125 颗额外的恒星，这些恒星呈现出表明年轻但没有可检测到锂的恒星活动迹象。WiFeS 光谱的径向速度测定精度为 3.2 km s-1 和 Echelle 样品的 1.5 km s-1。