论文标题
NGC 1193和NGC 1798使用CCD UBV光度法和GAIA EDR3数据的研究
A study of the NGC 1193 and NGC 1798 open clusters using CCD UBV photometric and Gaia EDR3 data
论文作者
论文摘要
我们介绍了旧的开放式明星簇NGC 1193和NGC 1798的光度法，天文和运动学研究。通过将GAIA EDR3和CCD UBV观测数据的数据集结合来研究两个簇。通过群集区域对恒星的径向分布的分析表明，对于两个簇，群集极限半径为$ r _ {\ rm lim} = 8'$。我们确定恒星的成员概率考虑GAIA EDR3适当的运动和三角视差数据，从而导致NGC 1193中的361颗恒星和NGC 1798的428颗恒星被确定为最有可能的群集成员，其成员概率大于p> 0.5。 NGC 1193和（$μ_207（0.009），-0.207（0.009），-0.431（0.008）$的平均适当运动组件估计为（$μ_α\cosδ$，$μ__Δ NGC 1193的E（B-V）颜色过量因使用两色图而得出了NGC 1193的$ 0.150（0.037）$，而NGC 1798 AS 0.505（0.100）Mag。还根据两色图确定光度金属率，NGC 1193的[Fe/H] = -0.30（0.06）Dex的结果为NGC 1798的[Fe/H] = -0.20（0.07）Dex。等速线拟合距离和年龄ngc 1193均为5562（381）（381）和4.6（381）和4.6（1）。对于NGC 1798，这些参数为4451（728）PC和1.3（0.2）GYR。这些年龄表明NGC 1193和NGC 1798是旧的开放群集。在NGC 1193的总体序列恒星的总体总质量斜率为1.38（2.16）和NGC 1798的1.30（0.21），这与Salpeter（1955）的价值公平一致。运动学和动态轨道计算表明，NGC 1193和NGC 1798分别属于厚盘和薄盘人群。此外，两个簇均出生在太阳圆之外，并且两个都在银河磁盘的金属贫困区域轨道。
We present photometric, astrometric, and kinematic studies of the old open star clusters NGC 1193 and NGC 1798. Both of the clusters are investigated by combining data sets from Gaia EDR3 and CCD UBV observational data. Analysis of the radial distribution of stars through the cluster regions indicates that the cluster limit radii are $r_{\rm lim}=8'$ for both of the clusters. We determine the membership probabilities of stars considering Gaia EDR3 proper motion and trigonometric parallax data, resulting in 361 stars in NGC 1193 and 428 in NGC 1798 being identified as most likely cluster members, having membership probabilities greater than P>0.5. Mean proper motion components are estimated as ($μ_α\cos δ$, $μ_δ) = (-0.207(0.009), -0.431(0.008)$) for NGC 1193 and ($μ_α\cos δ$, $μ_δ)=(0.793(0.006), -0.373(0.005)$) mas/yr for NGC 1798. E(B-V) color excesses were derived for NGC 1193 as $0.150(0.037)$ and for NGC 1798 as 0.505(0.100) mag through the use of two-color diagrams. Photometric metallicities are also determined from two-color diagrams with the results of [Fe/H] = -0.30(0.06) dex for NGC 1193 and [Fe/H]=-0.20(0.07) dex for NGC 1798. The isochrone fitting distance and age of NGC 1193 are 5562(381) pc and 4.6(1) Gyr, respectively. For NGC 1798, these parameters are 4451(728) pc and 1.3(0.2) Gyr. These ages indicate that NGC 1193 and NGC 1798 are old open clusters. The overall present-day mass function slopes for main-sequence stars are found as 1.38(2.16) for NGC 1193 and 1.30(0.21) for NGC 1798, which are in fair agreement with the value of Salpeter (1955). Kinematic and dynamic orbital calculations indicate that NGC 1193 and NGC 1798 belong to the thick-disk and thin-disk populations, respectively. In addition, both of the clusters were born outside the solar circle, and both orbit in the metal-poor region of the Galactic disk.
