Related papers: Orbital Stability of Multi-Planet Systems: Behavio…
Closely-packed multi-planet systems are known to experience dynamical instability if the spacings between the planets are too small. Such instability can be tempered by the frictional forces acting on the planets from gaseous discs. A…
Among $\sim 160$ of the multiple exoplanetary systems confirmed, about $30\%$ of them have neighboring pairs with a period ratio $\leq 2$. A significant fraction of these pairs are around mean motion resonance (MMR), more interestingly,…
The recently discovered planetary system HD45364 which consists of a Jupiter and Saturn mass planet is very likely in a 3:2 mean motion resonance. The standard scenario to form planetary commensurabilities is convergent migration of two…
Previous studies using Kepler data suggest that planets orbiting the same star tend to have similar sizes. However, due to the faintness of the stars, only a few of the planets were also detected with radial velocity follow-ups, and…
Star-planet interactions play, among other things, a crucial role in planetary orbital configurations by circularizing orbits, aligning the star and planet spin and synchronizing stellar rotation with orbital motions. This is especially…
We identify observational signatures suggesting a history of dynamical instability in 26 out of 34 M-dwarf multi-planet systems containing no large planets. These systems may have primarily formed in a gas-rich environment, potentially…
We present models for the formation of terrestrial planets, and the collisional evolution of debris disks, in planetary systems that contain multiple unstable gas giants. We previously showed that the dynamics of the giant planets…
Migration of planetary systems caused by the action of dissipative forces may lead the planets to be trapped in a resonance. In this work we study the conditions and the dynamics of such resonant trapping. Particularly, we are interested in…
We investigate the distributions of the orbital period ratios of adjacent planets in high multiplicity \kepler\ systems (four or more planets) and low multiplicity systems (two planets). Modeling the low multiplicity sample as essentially…
A system of four super-Jupiter planets around HR 8799 is the first multi-planet configuration discovered via the direct imaging technique. Despite over decade of research, the system's architecture remains not fully resolved. The main…
The relationship between the boundaries for Hill and Lagrange stability in orbital element space is modified in the case of resonantly interacting planets. Hill stability requires the ordering of the planets to remain constant while…
Exoplanets observed by the {\it Kepler} telescope exhibit a bi-modal, radius distribution, which is known as the radius gap. We explore an origin of the radius gap, focusing on multi-planet systems. Our simple theoretical argument predicts…
We investigate whether any multi-planet systems among Kepler candidates (2011 February release) can harbor additional terrestrial-mass planets or smaller bodies. We apply the "packed planetary systems" hypothesis that suggests all planetary…
Recent exoplanet surveys revealed that for solar-type stars, close-in Super-Earths are ubiquitous and many of them are in multi-planet systems. These systems are more compact than the Solar System's terrestrial planets. However, there have…
We describe numerical tools for the stability analysis of extrasolar planetary systems. In particular, we consider the relative Poincare variables and symplectic integration of the equations of motion. We apply the tangent map to derive a…
Many planets are observed in stellar binary systems, and their frequency may be comparable to that of planetary systems around single stars. Binary stellar evolution in such systems influences the dynamical evolution of the resident…
Since exoplanets were detected using the radial velocity method, they have revealed a diverse distribution of orbital configurations. Amongst these are planets in highly eccentric orbits (e > 0.5). Most of these systems consist of a single…
HR 8799 is a nearby star hosting at least four ~10 Jovian mass planets in wide orbits up to ~70au, detected through the direct, high-contrast infrared imaging. Large companions and debris disks reported interior to ~10au, and exterior to…
The extrasolar planetary system around HR 8799 is the first multiplanet system ever imaged. It is also, by a wide margin, the highest mass system with >27 Jupiters of planetary mass past 25 AU. This is a remarkable system with no analogue…
Planet formation occurs around a wide range of stellar masses and stellar system architectures. An improved understanding of the formation process can be achieved by studying it across the full parameter space, particularly toward the…