Institution(s): 1. Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences
The Kepler Mission by NASA is motivated to find more Earth-size planets in or near the habitable zone using the transit method. Till now, more than 4,100 planet candidates are released, of which about 40 percent planet candidates with the radius less than 4 R⊕orbiting the host stars in the single planet system are located within 0.1 AU. Generally, these planet sare called close-in terrestrial or Neptune-like planets, one special class of exoplanets observed by Kepler mission, and they are good examples to investigate planet information, since it is not clear for Earth-like planet formation in the current formation models. For such close-in planets, tidal effects are important to reshape the final orbits following a series of orbital migration such as disk migration, planetary scattering and in situ formation etc. In this work, we use various initial conditions, for example, random unit distribution and Rayleigh distribution of orbital semi-major axes and eccentricities will be investigated. All orbital elements are assumed to be close relative of possible certain migrations. Especially the in-situ formation mechanism is to be focused in this work. Numerical simulation results compared with the observations indicate that such planets are possible form near current positions as the Rayleigh distribution with the peak of semi-major axis between 0.05 and 0.1 AU. Results caused by other migration scenarios and various eccentricities, planetary or stellar masses and tidal dissipation parameters are also discussed.