Tracing Dynamical Evolution of Planetary Systems: From Protoplanets to Young and Mature Planetary Systems
Open Access
- Author:
- Dong, Jiayin
- Graduate Program:
- Astronomy and Astrophysics
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- May 31, 2022
- Committee Members:
- Bradford Foley, Outside Unit & Field Member
Rebekah Dawson, Chair & Dissertation Advisor
Jason Wright, Major Field Member
Eric Ford, Major & Minor Field Member
Kevin Luhman, Major Field Member
Rebekah Dawson, Program Head/Chair - Keywords:
- Exoplanets
Debris disks
Planet formation
Dynamics - Abstract:
- Dynamical imprints on planetary systems, such as planetary spin rate, orbital eccentricity, mutual inclination, and stellar obliquity provide direct evidence by which we can compare theoretical models of planet formation against observations. In this dissertation, I capitalized on these dynamical tracers to identify and model critical physical processes during multiple stages of planet formation and evolution. First, planetary spin is a fingerprint of planet formation and reflects how a forming gas giant planet interacts with its circumplanetary disk. Using hydrodynamic simulations, I showed there is a maximum spin rate a gas giant planet can spin up through its circumplanetary disk. In contrast to the classical view of planets accreting until their rotation reaches the breakup periods, planets can at most reach 60–80% of their breakup rates before their gaseous envelope accretion becomes decretion, accompanying solutions where angular momentum is being lost. The work complemented the existing giant planet accretion models and predicted the maximum spin rate on forming giant planets. Second, I used debris disks as an indirect probe of young planetary systems where strong stellar activity challenges planetary characterization. Using analytical studies and N-body simulations, I showed in most systems, debris disk features such as warps, eccentric rings, gaps, and azimuthal asymmetries are dominated by a single planet and can be used to interpret the young planet's properties. However, in a few system configurations where the detected planet is not the dominant planet of the disk features, the interpretation of the planet’s properties can be flawed by order of magnitudes. Lastly, orbital eccentricity and stellar obliquity are powerful tracers to the mature planet’s dynamical history. I focused on Warm Jupiters, which are giant planets with orbital periods between 8 to 200 days. The origin of Warm Jupiters was not clear and the investigation was limited by the small sample size. Using NASA’s Transiting Exoplanet Survey Satellite (TESS) and ground-based observing facilities, I discovered and characterized Warm Jupiters in TESS Full-Frame Image data. I led the discovery of TOI-3362b, a super eccentric Warm Jupiter suggesting the high-eccentricity tidal migration origin, and TOI-1268b, a young circular Warm Jupiter aligned with its host star suggesting an in-situ formation or disk migration origin. From both individual targets and the population study of the catalog on the eccentricity distribution study using hierarchical Bayesian modeling, I showed Warm Jupiters are likely from multiple origins.