疏散星团NGC2286的测光研究和HR图

Photometry and the HR Diagram of the Open Cluster NGC 2286

本文给出了疏散星团NGC2286天区中305颗恒星的照相B、V星等,结合其它资料得到了星团的平均色余值为E_(B-V)=0.40m±0.07m,距离模数10.90m±0.10m,相应的距离为r 1510pc±70pc,年龄估值为6×10~7年,由得到的星团HR图讨论了星团的其它性质。

Photographic V magnitudes and (B - V) colours in the UBV system are determined for 305 stars in the field of the open cluster NGC 2286, and the rms errors of V and (B - V) for one plate are estimated to be σv = 0.m063, and σB-v = 0.m084, respectively. The reddening value of the cluster is 0.m40±0.m07. The derived distance modulus to the cluster is approximately 10.m9±0.m1. Using the composite diagram method, the age of the cluster is estimated as 6 × 107 yr. The HR diagram of the cluster is obtained and discussed. Furthermore, a better determination of membership of the cluster is made based on the proper motion membership probabilities and the photometric data of these 305 stars.