Open clusters: their kinematics and metellicities

Abstract

We review our work on Galactic open clusters in recent years, and introduce our proposed large program for the LOCS (LAMOST Open Cluster Survey). First, based on the most complete open clusters sample with metallicity, age and distance data as well as kinematic information, some preliminary statistical analysis regarding the spatial and metallicity distributions is presented. In particular, a radial abundance gradient of - 0.058$\pm$ 0.006 dex kpc${}^{-1}$ was derived, and by dividing clusters into age groups we show that the disk abundance gradient was steeper in the past. Secondly, proper motions, membership probabilities, and velocity dispersions of stars in the regions of two very young open clusters are derived. Both clusters show clear evidence of mass segregation, which provides support for the ``primordial'' mass segregation scenarios. Based on the great advantages of the forthcoming LAMOST facility, we have proposed a detailed open cluster survey with LAMOST (the LOCS). The aim, feasibility, and the present development of the LOCS are briefly summarized.

7 pages, 4 figures, submitted to Proceeding of IAU Symposium No.248: "A Giant Step:from Milli- to Micro-arcsecond Astrometry"

References in corpus (3)

• Mass segregation in very young open clusters -- A case study of NGC 2244 and NGC 6530
• New results on the time variation of the radial abundance gradients from planetary nebulae
• An estimate of the time variation of the abundance gradient from planetary nebulae III. O, S, Ar, and Ne: A comparison of PN samples