论文标题

32 ORI与Gaia的人口普查

A Census of the 32 Ori Association with Gaia

论文作者

Luhman, K. L.

论文摘要

我已经使用了GAIA(DR3)第三个数据释放的高精度光度法和天文学来识别32 ORI关联的候选成员。使用新的和档案光谱测量了候选子集的光谱类型和径向速度。对于具有径向速度测量值的候选者,我已经使用UVW速度进一步限制了其成员资格,并获得了169个候选人的最终目录。我估计,对于<= m7的光谱类型(> = 0.06 msun),调查的完整性约为90%。 32个候选物的光谱类型的直方图在M5(〜0.15 msun)时表现出最大值,类似于针对太阳邻居中其他年轻群集和关联测得的分布。可用的UVW速度表明该关联正在扩大,但它们不会产生明确的运动年龄。基于它们在色彩图中的低质量恒星的序列,32 ORI关联和上半月形 - 卢普斯/下半月形crux(UCL/LCC)在+/- 1.2 MYR内均与beta PIC移动组更年轻。最后,我使用了来自宽阔红外调查探险家的中红外(IR)光度法,以检查32个候选物中的室外磁盘的过量发射。检测到18个候选人的磁盘,其中一半是在这项工作中首次报告。具有完整,过渡或进化的磁盘的<= M6的候选者分数为10/149 = 0.07+0.03/-0.02,这与UCL/LCC的值一致。

I have used high-precision photometry and astrometry from the third data release of Gaia (DR3) to identify candidate members of the 32 Ori association. Spectral types and radial velocities have been measured for subsets of the candidates using new and archival spectra. For the candidates that have radial velocity measurements, I have used UVW velocities to further constrain their membership, arriving at a final catalog of 169 candidates. I estimate that the completeness of the survey is ~90% for spectral types of <=M7 (>=0.06 Msun). The histogram of spectral types for the 32 Ori candidates exhibits a maximum at M5 (~0.15 Msun), resembling the distributions measured for other young clusters and associations in the solar neighborhood. The available UVW velocities indicate that the association is expanding, but they do not produce a well-defined kinematic age. Based on their sequences of low-mass stars in color-magnitude diagrams, the 32 Ori association and Upper Centaurus-Lupus/Lower Centaurus-Crux (UCL/LCC) are coeval to within +/-1.2 Myr, and they are younger than the Beta Pic moving group by ~3 Myr, which agrees with results from previous analysis based on the second data release of Gaia. Finally, I have used mid-infrared (IR) photometry from the Wide-field Infrared Survey Explorer to check for excess emission from circumstellar disks among the 32 Ori candidates. Disks are detected for 18 candidates, half of which are reported for the first time in this work. The fraction of candidates at <=M6 that have full, transitional, or evolved disks is 10/149=0.07+0.03/-0.02, which is consistent with the value for UCL/LCC.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源