论文标题
Pi Mensae行星系统的径向速度研究：Pi Mensae C和第三行星的改进的行星参数在125-D轨道上
A Radial Velocity Study of the Planetary System of Pi Mensae: Improved Planet Parameters for PI Mensae c and a Third Planet on a 125-d Orbit
论文作者
论文摘要
Pi Men主持了一个由苔丝太空任务检测到的过境行星，在RV调查发现的5.7年轨道中，一个外行星。我们使用HARPS光谱仪对ESO的3.6 m望远镜和档案数据进行了竖琴光谱仪进行的新径向速度（RV）测量研究了该系统。由于过境行星pi men c，我们限制了恒星RV半振幅，因为k_c = 1.21 +/- 0.12 m/s，导致m_c的行星质量为m_c = 3.63 +/- 0.38 m_earth。 R_C的行星半径= 2.145 +/- 0.015 r_earth产生的大量密度= 2.03 +/- 0.22 g/cm^{ - 3}。该行星的精确确定的密度和宿主恒星的亮度使PI MEN C成为内部结构和大气表征研究的绝佳实验室。我们的HARPS RV测量值还揭示了第三机构PI MEN D的令人信服的证据，其中最小质量m sin I = 13.38 +/- 1.35 m_earth轨道，p_d = 125 d = 125 d（e = 0.22）。一个简单的动力学分析表明，PI MEN D的轨道在至少20个MYR的时间尺度上是稳定的。鉴于外部气态巨人与内部岩石行星之间的相互倾向以及在125 d时存在第三尸体，因此Pi Men是动力学和形成研究的重要行星系统。
Pi Men hosts a transiting planet detected by the TESS space mission and an outer planet in a 5.7-yr orbit discovered by RV surveys. We studied this system using new radial velocity (RV) measurements taken with the HARPS spectrograph on ESO's 3.6-m telescope as well as archival data. We constrain the stellar RV semi-amplitude due to the transiting planet, Pi Men c, as K_c = 1.21 +/- 0.12 m/s resulting in a planet mass of M_c = 3.63 +/- 0.38 M_Earth. A planet radius of R_c= 2.145 +/- 0.015 R_Earth yields a bulk density of rho = 2.03 +/- 0.22 g/cm^{-3}. The precisely determined density of this planet and the brightness of the host star make Pi Men c an excellent laboratory for internal structure and atmospheric characterization studies. Our HARPS RV measurements also reveal compelling evidence for a third body, PI Men d, with a minimum mass M sin i = 13.38 +/- 1.35 M_Earth orbiting with a period of P_d = 125 d on an eccentric orbit (e = 0.22). A simple dynamical analysis indicates that the orbit of Pi Men d is stable on timescales of at least 20 Myrs. Given the mutual inclination between the outer gaseous giant and the inner rocky planet and the presence of a third body at 125 d, Pi Men is an important planetary system for dynamical and formation studies.
