Precise calibration of the dependence of surface brightness–colour relations on colour and class for late-type stars
Precise calibration of the dependence of surface brightness–colour relations on colour and class for late-type stars
复制标题
精确校准晚型恒星表面亮度和颜色关系对颜色和等级的依赖性
DOI：
10.1051/0004-6361/202038012
复制
发表时间：
2020
影响因子：
6.5
通讯作者：
Farrington, C. D.
中科院分区：
文献类型：
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作者：
Salsi, A.;Nardetto, N.;Mourard, D.;Creevey, O.;Huber, D.;White, T. R.;Hocdé, V.;Morand, F.;Tallon-Bosc, I.;Farrington, C. D.
上下文表面亮度-颜色关系（SBCR）用于从光度观测中推导恒星角直径。它们在天体物理学上有各种应用，例如确定食双星的距离或确定系外行星的参数。然而，强烈的SBCRs之间的差异仍然存在于文献中，特别是对于早期和晚期的类型stars.AimsWe的目标是校准新的SBCRs的光谱类型和光度类的恒星的函数。我们的目标也是应用均匀的标准来选择的参考星，并在编译一个详尽的和最新的列表中的干涉测量晚型targetsMethodsWe实施的标准来选择测量的JMMC测量直径目录。然后，我们应用额外的标准上的光度测量用于建立SBCRs，连同恒星特征diagnostics.ResultsWe建立SBCRs的F5/K7-II/III，F5/K7-IV/V，M-II/III和M-V星，与各自的均方根σFV= 0.0022马格，σFV= 0.0044马格，σFV= 0.0046马格，和σFV= 0.0038马格。这导致在角直径的精度为1.0%，2.0%，2.1%，和1.7%，分别。 这些关系涵盖了从1到7.5的大V − K色星等范围。我们的工作表明，SBCR显着依赖于光谱类型和光度类的星星。通过一组新的干涉测量，我们证明了SBCR校准的选择标准的至关重要性。最后，利用Gaiophotometry对我们的样品进行了测量，得到了角直径精度在1.1%~ 2.4%之间的（G-K）SBCR。结论通过采用一种精细的均匀方法，我们表明在应用SBCR时应考虑光谱类型和星星的类。这一点在PLATO的范围内尤其重要。
ContextSurface brightness–colour relations (SBCRs) are used to derive the stellar angular diameters from photometric observations. They have various astrophysical applications, such as the distance determination of eclipsing binaries or the determination of exoplanet parameters. However, strong discrepancies between the SBCRs still exist in the literature, in particular for early and late-type stars.AimsWe aim to calibrate new SBCRs as a function of the spectral type and the luminosity class of the stars. Our goal is also to apply homogeneous criteria to the selection of the reference stars and in view of compiling an exhaustive and up-to-date list of interferometric late-type targets.MethodsWe implemented criteria to select measurements in the JMMC Measured Diameters Catalog. We then applied additional criteria on the photometric measurements used to build the SBCRs, together with stellar characteristics diagnostics.ResultsWe built SBCRs for F5/K7–II/III, F5/K7–IV/V, M–II/III and M–V stars, with respective rms ofσFV= 0.0022 mag,σFV= 0.0044 mag,σFV= 0.0046 mag, andσFV= 0.0038 mag. This results in a precision on the angular diameter of 1.0%, 2.0%, 2.1%, and 1.7%, respectively. These relations cover a largeV−Kcolour range of magnitude, from 1 to 7.5. Our work demonstrates that SBCRs are significantly dependent on the spectral type and the luminosity class of the star. Through a new set of interferometric measurements, we demonstrate the critical importance of the selection criteria proposed for the calibration of SBCR. Finally, using theGaiaphotometry for our samples, we obtained (G−K) SBCRs with a precision on the angular diameter between 1.1% and 2.4%.ConclusionsBy adopting a refined and homogeneous methodology, we show that the spectral type and the class of the star should be considered when applying an SBCR. This is particularly important in the context of PLATO.