Stellar Spin-Orbit Alignment for Kepler-9, a Multi-transiting Planetary System with Two Outer Planets Near 2:1 Resonance

作者：Wang Songhu^*; Addison Brett; Fischer Debra A; Brewer John M; Isaacson Howard; Howard Andrew W; Laughlin Gregory

来源：Astronomical Journal, 2018, 155(2): 70.

DOI：10.3847/1538-3881/aaa2fb

• methods: observational
• planetary systems
• planets and satellites: individual (Kepler-9b)
• stars:individual (Kepler-9)
• techniques: radial velocities
• techniques: spectroscopic

We present spectroscopic measurements of the Rossiter-McLaughlin effect for the planet b of the Kepler-9 multi-transiting planetary system. The resulting sky-projected spin-orbit angle is lambda = -13 degrees +/- 16 degrees, which favors an aligned system and strongly disfavors highly misaligned, polar, and retrograde orbits. Including Kepler-9, there are now a total of four Rossiter-McLaughlin effect measurements for multiplanet systems, all of which are consistent with spin-orbit alignment.

• 出版日期2018-2