We report the discovery by the ground-based HATNet survey of the transiting exoplanet HAT-P-68b, which has a mass of 0.724 $\pm$ 0.043 $M_{Jup}$, and radius of 1.072 $\pm$ 0.012 $R_{Jup}$. The planet is in a circular P = 2.2984-day orbit around a moderately bright V = 13.937 $\pm$ 0.030 magnitude K dwarf star of mass 0.673 $+$ 0.020 $-$0.014 $M_{\odot}$, and radius 0.6726 $\pm$ 0.0069 $R_{\odot}$. The planetary nature of this system is confirmed through follow-up transit photometry obtained with the FLWO~1.2m telescope, high-precision RVs measured using Keck-I/HIRES, FLWO~1.5m/TRES, and OHP~1.9m/Sophie, and high-spatial-resolution speckle imaging from WIYN~3.5m/DSSI. HAT-P-68 is at an ecliptic latitude of $+3^{\circ}$ and outside the field of view of both the NASA TESS primary mission and the K2 mission. The large transit depth of 0.036 mag ($r$-band) makes HAT-P-68b a promising target for atmospheric characterization via transmission spectroscopy.

中文翻译：

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HAT-P-68b：围绕 K5 矮星运行的热木星

我们报告了地面 HATNet 对凌日系外行星 HAT-P-68b 的发现，它的质量为 0.724 $\pm$ 0.043 $M_{Jup}$，半径为 1.072 $\pm$ 0.012 $R_ {Jup}$。这颗行星处于圆形 P = 2.2984 天轨道，围绕一颗中等亮度 V = 13.937 $\pm$ 0.030 星等 K 矮星，质量为 0.673 $+$ 0.020 $-0.014 $M_{\odot}$，半径为 0.6726 $ \pm$ 0.0069 $R_{\odot}$。该系统的行星性质通过使用 FLWO~1.2m 望远镜获得的后续凌日光度测量、使用 Keck-I/HIRES、FLWO~1.5m/TRES 和 OHP~1.9m/Sophie 测量的高精度 RV 得到证实，和来自 WIYN~3.5m/DSSI 的高空间分辨率散斑成像。HAT-P-68 位于黄道纬度 $+3^{\circ}$ 并且在 NASA TESS 主要任务和 K2 任务的视野之外。大过境深度0。