论文标题
Wiyn开放集群研究。 lxxvii。开放群集NGC 7789中的径向速度测量和光谱二进制轨道
WIYN Open Cluster Study. LXXVII. Radial-Velocity Measurements and Spectroscopic Binary Orbits in the Open Cluster NGC 7789
论文作者
论文摘要
我们介绍了富含开放群集NGC 7789(1.6 Gyr,[Fe/H] = +0.02)的Wiyn开放群集研究径向速度调查的恒星样品。该样本位于群集中心(投影10 pc或大约2个核心半径)的18 $'$圆形半径内,包括巨人,红色笨拙的恒星,蓝色散落者,红色散乱者,次级套件和主序列和主序列,以下是下面下方的一个磁场。我们的调查始于2005年,由WIYN 350万望远镜的Hydra多对象光谱仪进行了9,000多个径向速度测量。我们确定了564个可能的集群成员,并为83个集群二进制恒星提供轨道解决方案,周期为1.45 $ \,$ d和4200 $ \,$ d。从主要序列二进制解决方案中,我们适合8.22 $^{+3.51} _ { - 1.35} \,$ d的循环周期。我们计算出不完整校正的主要序列二进制频率为31%$ \ pm $ 3%的二进制二进制频率,而周期少于10 $^{4} $天,类似于其他所有年龄段的WOC。我们检测到31%$ \ pm $ 15%的蓝色Straggler二进制频率,与类似老化的群集NGC 6819一致。
We introduce the stellar sample of the WIYN Open Cluster Study radial-velocity survey for the rich open cluster NGC 7789 (1.6 Gyr, [Fe/H] = +0.02). This sample lies within an 18$'$ circular radius from the cluster center (10 pc in projection, or about 2 core radii), and includes giants, red-clump stars, blue stragglers, red stragglers, sub-subgiants, and main-sequence stars down to one mag below the turnoff. Our survey began in 2005 and comprises more than 9,000 radial-velocity measurements from the Hydra Multi-Object Spectrograph on the WIYN 3.5m telescope. We identify 564 likely cluster members and present the orbital solutions for 83 cluster binary stars with periods between 1.45$\,$d and 4200$\,$d. From the main-sequence binary solutions we fit a circularization period of 8.22$^{+3.51}_{-1.35}\,$d. We calculate an incompleteness-corrected main-sequence binary frequency of 31% $\pm$ 3% for binaries with periods less than 10$^{4}$ days, similar to other WOCS open clusters of all ages. We detect a blue straggler binary frequency of 31% $\pm$ 15%, consistent with the similarly aged cluster NGC 6819.