We conducted interferometric observations with the CHARA Array of transiting super-Earth host HD 97658 and measured its limb-darkened angular diameter to be θ _LD = 0.314 0.004 mas. The combination of the angular diameter with the Gaia EDR3 parallax value with zero-point correction (π = 46.412 0.022 mas, d =21.546 0.011 pc) yields a physical radius of R _⋆ = 0.728 0.008 R _⊙. We also measured the bolometric flux of the star to be F _bol = 2.42 0.05 10⁻⁸ erg s⁻¹ cm⁻², which, together with angular size, allows a measurement of the effective temperature T _eff = 5212 43 K. Our directly determined physical stellar properties are in good agreement with previous estimates derived from spectroscopy. We used our measurements in combination with stellar evolutionary models and properties of the transit of HD 97658 b to determine the mass and age of HD 97658 as well as constrain the properties of the planet. Our results and our analysis of the TESS light curve on the planet (TOI-1821) corroborate previous studies of this system with tighter uncertainties.

我们对凌日超级地球宿主 HD 97658 的 CHARA 阵列进行了干涉观测，并测量了其边缘变暗角直径为θ _LD = 0.314 0.004 mas。角直径与 Gaia EDR3 视差值与零点校正 ( π = 46.412 0.022 mas, d =21.546 0.011 pc) 的组合产生物理半径R _⋆ = 0.728 0.008 R _⊙。我们还测量了恒星的热通量F _bol = 2.42 0.05 10 ^-8 erg s ^-1 cm ^-2，这与角尺寸一起允许测量有效温度T _eff = 5212 43 K。我们直接确定的恒星物理性质与先前从光谱学得出的估计值非常一致。我们将测量结果与恒星演化模型和 HD 97658 b 凌日的特性相结合，以确定 HD 97658 的质量和年龄，并限制行星的特性。我们的结果和我们对地球上 TESS 光变曲线 (TOI-1821) 的分析证实了之前对该系统的研究，但具有更严格的不确定性。