Special Issue for LAMOST Sciences

Candidate members of star clusters from LAMOST DR2

Bo Zhang, Xiao-Yan Chen, Chao Liu, Li Chen, Li-Cai Deng, Jin-Liang Hou, Zheng-Yi Shao, Fan Yang, Yue Wu, Ming Yang, Yong Zhang, Yong-Hui Hou, Yue-Fei Wang


Abstract In this work, we provide 2189 photometrically- and kinematically-selected candidate members of 24 star clusters from the LAMOST DR2 catalog. We perform two-step membership identification: selection along the stellar track in the color-magnitude diagram, i.e., photometric identification, and selection from the distribution of radial velocities, i.e. the kinematic identification. We find that the radial velocities from the LAMOST data are very helpful in the membership identification. The mean probability of membership is 40% for the sample selected with radial velocity. With these 24 star clusters, we investigate the performance of the radial velocity and metallicity estimated with the LAMOST pipeline. We find that the systematic offsets in radial velocity and metallicity are 0.85 ± 1.26 km s−1 and −0.08 ± 0.04 dex, with dispersions of 5.47+1.16−0.71 km s−1 and 0.13+0.04 −0.02 dex, respectively. Finally, we propose that the photometrically-selected candidate members of the clusters covered by the LAMOST footprint should be assigned higher priority so that more candidate stars can be observed.


Keywords open clusters and associations: general — stars: statistics — catalogs — surveys — methods: data analysis

Full Text

  • There are currently no refbacks.