发表机构
Laboratoire Lagrange, Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS; The CHARA Array of Georgia State University, Mount Wilson Observatory（拉格朗日实验室，蔚蓝海岸大学，蔚蓝海岸天文台，法国国家科学研究中心; 佐治亚州立大学查拉阵列，威尔逊山天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究针对PLATO空间任务，对18颗FGK-IV/V型恒星开展多色干涉观测，结合iSpec工具确定恒星参数，发现SBCR与文献校准结果存在差异，完成了盖亚波段SBCR的高精度校准，为后续研究提供理想样本。
AI 中文摘要
恒星角直径可通过表面亮度-色指数关系（SBCR）与测光来估算。PLATO空间任务将SBCR作为估算FGK型恒星光度的独立经验替代方法。在此背景下，我们不仅实现了均匀方法校准FGK-IV/V型恒星的SBCR，还确定了它们的基本参数，以便将恒星可靠地置于赫罗图（HR diagram）上，并研究其对SBCR的影响。我们对盖亚（Gaia）色指数范围为3.088≤G≤5.498的18颗宁静FGK-IV/V型恒星进行了干涉观测，首次使用3台分别工作在R、H、K波段的不同干涉仪来测量多色临边昏暗角直径（LDAD）。同时，我们使用开源Python工具iSpec，通过公共领域光谱估算了恒星基本参数（有效温度Teff、表面重力log g和金属丰度Z）。基于多色观测，我们获得的LDAD平均精度为2.3%。然而，我们发现本研究的SBCR不符合文献中盖亚波段表面亮度与色指数关系的校准结果。此外，我们发现log g和Z对SBC关系无影响；鉴于本研究宁静恒星样本的特征，它构成了在PLATO空间任务框架内开展新SBCR校准的理想目标集合。在此背景下，我们报告了SBCR校准结果，其在盖亚G、GBP、GRP波段的均方根误差（σRMS）分别为0.012、0.009、0.009。本文是一系列论文中的一篇，这些论文报告了使用多色方法测量LDAD的首批结果，该方法采用完全均匀的方法来确定恒星基本参数并测量LDAD（θLD）。
英文摘要
The estimation of stellar angular diameters can be performed from the surface brightness - color relation (SBCR) and photometry. The SBCR have been considered by the PLATO space mission as an independent empirical alternative for estimating stellar radii of FGK stars. In this context, we have implemented an homogeneous approach not only for calibrating the SBCR for FGK-IV/V stars but, also for determining their fundamental parameters in order to place the stars reliably on the HR diagram and to study their impact on the SBCR. We have performed interferometric observations of 18 quiescent FGK-IV/V stars in the Gaia color range of $3.088 \leq G \leq 5.498$. For the first time, we used 3 different interferometers operating in the $R$, $H$ , and $K$ bands to measure polychromatic limb-darkened angular diameters (LDAD). In parallel, by using public domain spectra we have estimated the stellar parameters ($T_{eff}$, $log g$ and Z) by using the open python tool iSpec. We achieved an average accuracy of 2.3% for the LDAD based on polychromatic observations. However, we have observed that our SBCR does not follow the calibration of the relation between surface brightness and color in Gaia found in the literature. Furthermore, we found that $log g$ and $Z$ have no impact on the SBC relation; given the characteristics of our sample of quiescent stars, it constitutes an ideal set of targets for conducting a new SBCR calibration within the framework of the PLATO space mission. In this context, we reported a SBCR calibration with $σ_{RMS} = $ 0.012, 0.009, 0.009 in the $G, G_{BP}$ and $G_{RP}$ Gaia bands, respectively. This article is part of a series of papers reporting the first results obtained using a polychromatic approach to measure LDAD, employing a fully homogeneous methodology for both determining the fundamental parameters of stars and measuring the LDAD, $θ_{LD}$.
