论文标题
在四个敞开的星团中搜索可变星
A Search for variable stars in the four open star clusters
论文作者
论文摘要
我们提出了一项CCD光度调查，用于在四个开放群集中搜索可变恒星的搜索，即伯克利69，国王5，King 7和伯克利20。时间序列观测是为1998年的每个聚类进行了1和/或2夜的时间序列观测，这些观测结果已导致这些clusters识别出这些clusters的恒星。在这19个变量的恒星中，五颗星显示出Delta Scuti，例如变异性，两颗星形显示了UMA类型的变异性。在其他恒星中，由于缺乏足够的数据，我们找不到周期，因此由于缺乏足够的数据而导致的可变性类型。发现Delta Scuti型恒星的周期在0.13至0.21天内，而伯克利群集20恒星的范围分别为0.396和0.418天。使用GAIA数据，还修改了伯克利69，King 7和King 5的集群的基本参数。据估计，伯克利69的年龄和红色为0.79 \ pm 0.09 Gyr，0.68 \ pm 0.03 mag，0.79 \ pm 0.09 Gyr和1.22 \ pm 0.03毫克，国王7和1.59 \ pm 0.19 gyr和0.63 gyr和0.63 \ pm 0.63 \ pm 0.02 \ pm 0.02 \ pm 0.02 mag for the for the for the for the for the for the for for pm 0.02 mag 5。在群集7和国王5中发现了大规模隔离的签名。
We present a CCD photometric survey for the search of variable stars in four open clusters namely Berkeley 69, King 5, King 7, and Berkeley 20. The time series observations were carried out for 1 and/or 2 nights for each of the clusters in the year 1998, which have led to identify nineteen variable stars in these clusters. Out of these 19 variable stars, five stars show delta Scuti like variability and two stars show W UMa type variability. In other stars, we could not find the periods and hence the type of variability due to the lack of sufficient data. The periods of delta Scuti type stars are found to be in the range of 0.13 to 0.21 days, whereas the two stars in the cluster Berkeley 20, which showed W UMa type variability have orbital periods of 0.396 and 0.418 days, respectively. Using the Gaia data, the basic parameters of the clusters Berkeley 69, King 7 and King 5 are also revised. The age and reddening are estimated to be 0.79 \pm 0.09 Gyr and 0.68 \pm 0.03 mag for Berkeley 69, 0.79 \pm 0.09 Gyr and 1.22 \pm 0.03mag for the cluster King 7 and 1.59 \pm 0.19 Gyr and 0.63 \pm 0.02 mag for the cluster King 5, respectively. Signature of mass segregation is found in the clusters King 7 and King 5.
