AI 中文总结
本研究利用Gaia DR3数据对27个King疏散星团开展均匀分析，确定其多参数并验证其作为银盘示踪体的作用，发现其金属丰度梯度与银盘疏散星团整体一致，年轻星团梯度更平缓。
AI 中文摘要
本研究旨在建立一组内部均匀的King疏散星团结构、天体物理及运动学参数，并评估它们作为银盘示踪体的作用。我们利用高精度Gaia DR3天体测量、测光和光谱数据，对27个King疏散星团开展了均匀的结构、天体物理及运动学分析。通过对Gaia色-星等图应用均匀马尔可夫链蒙特卡罗（Markov Chain Monte Carlo）等时线拟合方法，确定了星团的红化值、距离、金属丰度和年龄。推导得到的参数范围为：E(G_BP-G_RP)=0.113-1.933 mag，金属丰度[Fe/H]=-0.40至+0.28 dex，年龄17至6166 Myr，日心距离739至6272 pc。将天体测量距离与等时线法距离进行比较，得到的中位视差差为-13μas，表明在采用的均匀框架内，测光与天体测量距离标度之间具有良好的内部一致性。还利用三种互补的银盘距离定义，对King星团的径向金属丰度行为进行了检验，并与文献中164个经光谱分析的疏散星团独立得到的金属丰度-半径关系进行了对比。King星团的梯度接近-0.060 dex kpc⁻¹，与外部参考样本的梯度大致一致，表明经均匀分析的King星团遵循银盘疏散星团整体所呈现的负金属丰度-半径趋势。年轻星团的梯度更平缓，说明近期的化学增丰更为均匀。当应用动力学约束以减小径向迁移和轨道模糊的影响时，推断出的梯度仍接近-0.059 dex kpc⁻¹。
英文摘要
This study aims to establish an internally homogeneous set of structural, astrophysical, and kinematical parameters for King open clusters and to assess their role as tracers of the Galactic thin disc. We present a homogeneous structural, astrophysical, and kinematical analysis of 27 King open clusters using high-precision Gaia DR3 astrometry, photometry, and spectroscopy. Cluster reddenings, distances, metallicities, and ages are determined via a homogeneous Markov Chain Monte Carlo isochrone-fitting approach applied to Gaia colour-magnitude diagrams. The derived parameters span E(G_BP-G_RP) = 0.113-1.933 mag, metallicities of [Fe/H] = -0.40 to +0.28 dex, ages from 17 to 6166 Myr, and heliocentric distances between 739 and 6272 pc. A comparison between astrometric and isochrone-based distances yields a median parallax difference of $-13μ$as, indicating a good level of internal consistency between the photometric and astrometric distance scales within the adopted homogeneous framework. The radial metallicity behaviour of the King clusters is also examined using three complementary Galactic distance definitions and compared with the metallicity-radius relations obtained independently from 164 spectroscopically analysed open clusters from the literature. The King-cluster gradients are close to $-0.060$ dex kpc$^{-1}$ and are broadly consistent with those of the external reference sample, indicating that the homogeneously analysed King clusters follow the negative metallicity-radius trend traced by the broader thin-disc open-cluster population. Flatter gradients are found for young clusters, suggesting more homogeneous chemical enrichment at recent epochs. When dynamical constraints are applied to reduce the effects of radial migration and orbital blurring, the inferred gradient remains close to $-0.059$ dex kpc$^{-1}$.
Comments40 pages, 18 figures, 7 tables. Accepted for publication in Advances in Space Research
