论文标题
TOI-1759 b：围绕一个低质量恒星的过渡亚呼吸，以螺丝和苔丝为特征
TOI-1759 b: a transiting sub-Neptune around a low mass star characterized with SPIRou and TESS
论文作者
论文摘要
我们使用来自CFHT上SPIROU的TESS和近红外光谱数据的光度序列报告了过境亚北极TOI-1759 B的检测和表征。 TOI-1759 B旋转中等活跃的M0V星，其轨道周期为$ 18.849975 \ pm0.000006 $ d，我们测量行星半径和质量为$ 3.06 \ pm0.22 $ r $ _ \ r $ _ \ oplus $和$ 6.8 \ pm2.0 \ pm2.0 $ m $ m $ _ \ oplus $。使用CCF和LBL方法从螺旋光谱中提取径向速度，以优化近红外域中的速度测量值。我们分析了恒星和高分辨率螺旋光谱的宽带SED来限制恒星参数，从而提高了派生行星参数的准确性。对Spiou Stokes $ V $偏光光谱的LSD分析检测到TOI-1759中的Zeeman签名。我们使用具有准周期协方差函数的GP回归对磁性恒星活性的旋转调制进行建模，并找到$ 35.65^{+0.17} _ { - 0.15} $ d的旋转周期。我们使用ZDI重建恒星的大规模表面磁场，该ZDI的平均强度为$ 18 \ pm4 $ g。最后，我们对苔丝光度法和螺旋RV进行了联合贝叶斯MCMC分析，以最佳地限制系统参数。该星球以$ 0.1176 \ pm0.0013 $ au的价格收到了$ 6.4 $ $ $倍的玻璃液压通量事件，其平衡温度估计为$ 433 \ pm14 $K。TOI-1759 b。因此，寻找中性氢逃生是一个有趣的目标，这可能会对观察到的亚北极半径沙漠的行星形成机制提供重要的限制。
We report the detection and characterization of the transiting sub-Neptune TOI-1759 b, using photometric time-series from TESS and near infrared spectropolarimetric data from SPIRou on the CFHT. TOI-1759 b orbits a moderately active M0V star with an orbital period of $18.849975\pm0.000006$ d, and we measure a planetary radius and mass of $3.06\pm0.22$ R$_\oplus$ and $6.8\pm2.0$ M$_\oplus$. Radial velocities were extracted from the SPIRou spectra using both the CCF and the LBL methods, optimizing the velocity measurements in the near infrared domain. We analyzed the broadband SED of the star and the high-resolution SPIRou spectra to constrain the stellar parameters and thus improve the accuracy of the derived planet parameters. A LSD analysis of the SPIRou Stokes $V$ polarized spectra detects Zeeman signatures in TOI-1759. We model the rotational modulation of the magnetic stellar activity using a GP regression with a quasi-periodic covariance function, and find a rotation period of $35.65^{+0.17}_{-0.15}$ d. We reconstruct the large-scale surface magnetic field of the star using ZDI, which gives a predominantly poloidal field with a mean strength of $18\pm4$ G. Finally, we perform a joint Bayesian MCMC analysis of the TESS photometry and SPIRou RVs to optimally constrain the system parameters. At $0.1176\pm0.0013$ au from the star, the planet receives $6.4$ times the bolometric flux incident on Earth, and its equilibrium temperature is estimated at $433\pm14$ K. TOI-1759 b is a likely gas-dominated sub-Neptune with an expected high rate of photoevaporation. Therefore, it is an interesting target to search for neutral hydrogen escape, which may provide important constraints on the planetary formation mechanisms responsible for the observed sub-Neptune radius desert.
