相关论文: Sub-Neptune Formation: The View from Resonant Plan…
The aim of this work is to study the impact of a binary companion on the evolution of two-planet systems during both the type-II migration phase and their long-term evolution after the dissipation of the protoplanetary disk. We use the…
We study galaxy mergers with various mass ratios using N-body simulations, with an emphasis on the unequal-mass mergers in the relatively unexplored range of mass-ratios 4:1-10:1. Our recent work (Bournaud et al. 2004) shows that the above…
Pebble accretion refers to the assembly of rocky planet cores from particles whose velocity dispersions are damped by drag from circumstellar disc gas. Accretion cross-sections can approach maximal Hill-sphere scales for particles whose…
Close-in planetary systems detected by the Kepler mission present an excess of periods ratio that are just slightly larger than some low order resonant values. This feature occurs naturally when resonant couples undergo dissipation that…
Planets close to their stars are thought to form farther out and migrate inward due to angular momentum exchange with gaseous protoplanetary disks. This process can produce systems of planets in co-orbital (Trojan or 1:1) resonance, in…
We perform several suites of highly detailed dynamical simulations to investigate the architectures of the 24 Sextantis and HD 200964 planetary systems. The best fit orbital solution for the two planets in the 24 Sex system places them on…
Observed high multiplicity planetary systems are often tightly packed. Numerical studies indicate that such systems are susceptible to dynamical instabilities. Dynamical instabilities in close-in tightly packed systems, similar to those…
We present a theoretical framework for investigating a two-planet system undergoing convergent type I migration in a protoplanetary disk. Our study identifies the conditions for resonant capture and subsequent dynamical stability. By…
A number of multiplanet systems are observed to contain planets very close to mean motion resonances, although there is no significant pileup of precise resonance pairs. We present theoretical and numerical studies on the outcome of capture…
The late-stage formation of giant planetary systems is rich in interesting dynamical mechanisms. Previous simulations of three giant planets initially on quasi-circular and quasi-coplanar orbits in the gas disc have shown that highly…
We report the discovery of a sub-Neptune and a Neptune-like planet ($R_b = 2.48^{+0.14}_{-0.10}\,R_\oplus$, $R_c = 4.03^{+0.23}_{-0.15}\,R_\oplus$) orbiting the F-type star TOI-4495. The planets have orbital periods of 2.567 days and 5.185…
Orbits of known extrasolar planets that are located outside the tidal circularization regions of their parent stars are often substantially eccentric. By contrast, planetary orbits in our Solar System are approximately circular, reflecting…
The regular satellites found around Neptune ($\approx 17~M_{\Earth}$) and Uranus ($\approx 14.5~M_{\Earth}$) suggest that past gaseous circumplanetary disks may have co-existed with solids around sub-Neptune-mass protoplanets ($<…
The core accretion theory of planet formation has at least two fundamental problems explaining the origins of Uranus and Neptune: (1) dynamical times in the trans-Saturnian solar nebula are so long that core growth can take > 15 Myr, and…
Trans-Neptunian Objects (TNOs) in the scattered disk with 50 < a < 100 au are thought to cluster near Neptune's n:1 resonances (e.g: 3:1, 4:1, and so on). While these objects spend lengthy periods of time at large heliocentric distances, if…
K2-19 hosts a planetary system composed of two outer planets, b and c, with size of $7.0\pm 0.2~R_\oplus$ and $4.1\pm0.2~R_\oplus$ , and an inner planet, d, with a radius of $1.11\pm 0.05 R_\oplus$. A recent analysis of Transit-Timing…
The formation of multiple close-in low-mass exoplanets is still a mystery. The challenge is to build a system wherein the outermost planet is beyond 0.2 AU from the star. Here we investigate how the prescription for type I planet migration…
We describe a method to extract resonant orbits from N-body simulations exploiting the fact that they close in a frame rotating with a constant pattern speed. Our method is applied to the N-body simulation of the Milky Way by Shen et al.…
TRAPPIST-1 is a late M-dwarf orbited by seven Earth-sized planets with orbital period ratios near a chain of mean motion resonances. Due to uncertain system parameters, most orbital configurations drawn from the inferred posterior…
Giant collisions can account for Uranus's and Neptune's large obliquities, yet generating two planets with widely different tilts and strikingly similar spin rates is a low-probability event. Trapping into a secular spin-orbit resonance, a…