S20B0103abst
S20B0103
The origin of close-in giant planets (hot Jupiters and Neptunes) is the most enduring problem in exoplanetary science. A promising approach to solve this problem is to measure the angle of host star’s spin with respect to the planetary orbital axis (so-called “stellar obliquity"). This is because the various migration theories for close-in planets differ strongly in their predictions on the obliquity. Measurements of the stellar obliquity have been almost exclusively conducted for “solar-type" stars for their brightness and moderate rotation velocities, allowing us to investigate the dynamical history of close-in planets around those stars, but little is known on the formation and evolution of close-in planets around low-mass stars (M dwarfs), which are much more abundant in the Galaxy. Here, we propose a Subaru/IRD observation of the Rossiter-McLaughlin effect for a hot, super-Neptune GJ 3470b, which is one of the largest transiting planet orbiting a bright M dwarf. The comparison between the obliquity distributions for solar-type and low-mass stars would provide the key piece of information to solve the mystery on the origin of close-in giant planets.
This document was translated from LATEX by HEVEA.