论文标题
NGC 2158在Gaia时代的全面分析：光度参数，顶点和轨道
A comprehensive analysis of NGC 2158 in Gaia era: photometric parameters, apex and orbit
论文作者
论文摘要
我们使用GAIA-DR2数据对NGC 2158进行了研究。我们确定了800个最有可能成员概率高于90％的集群成员。该对象的平均正确运动被确定为（mu_ {x} = -0.203 \ pm 0.003，mu_ {y} = -1.99 \ pm 0.004）mas yr^{ - 1}。群集的限制半径，日志（年龄）和距离分别为23.5 Arcmin，9.38 \ pm 0.04 Gyr和4.69 \ pm 0.22 kpc。总体质量函数斜率（0.93 \ pm 0.14）比质量范围1.17-1.44 m_ \ odot范围内的salpeter值（1.35）更平坦。该群集还显示了质量分析效应，我们的研究表明NGC 2158是动态放松的开放式群集。使用AD-DIAGRAGR，以不同的方式获得群集的顶点坐标，并使用（μ_{U}，μ_{t}）图进行检查。顶点坐标的最佳值确定为a = 87.24^\ circ \ pm 1.60^\ circ，d = -36.61^\ circ \ pm 5.30^\ circ。我们还确定了集群的轨道，发现NGC 2158几乎移动在太阳Antapex方向上。 NGC 2158的结果空间速度为51 km s^{ - 1}。检测到沿Z坐标高达529〜PC的显着振荡。还讨论了有关该集群起源的各种方案。
We present an investigation of NGC 2158 using Gaia-DR2 data. We identified 800 most likely cluster members with membership probability higher than 90%. The mean proper motions of this object are determined as (mu_{x}=-0.203 \pm 0.003, mu_{y}=-1.99 \pm 0.004) mas yr^{-1}. The limiting radius, log(age), and distance of the cluster are obtained as 23.5 arcmin, 9.38 \pm 0.04 Gyr and 4.69 \pm 0.22 kpc, respectively. The overall mass function slope (0.93 \pm 0.14) is flatter than the Salpeter value (1.35) within the mass range 1.17-1.44 M_\odot. This cluster also shows the mass-segregation effect and our study demonstrates that NGC 2158 is a dynamically relaxed open cluster. Using the AD-diagram, the apex coordinates of the cluster are obtained in different ways and examined using (μ_{U},μ_{T}) diagram. The best value of apex coordinates is determined as A=87.24^\circ \pm 1.60^\circ, D=-36.61^\circ \pm 5.30 ^\circ. We also determined the orbit of the cluster and found that NGC 2158 moves almost in the Solar antapex direction. The resulting spatial velocity of NGC 2158 is 51 km s^{-1}. A significant oscillations along the Z-coordinate up to 529~pc is detected. Various scenarios regarding the origin of this cluster are also discussed.
