相关论文: Overcoming migration during giant planet formation
We examine a physical process that leads to the efficient formation of gas giant planets around intermediate mass stars. In the gaseous protoplanetary disks surrounding rapidly-accreting intermediate-mass stars we show that the midplane…
Gas accretion is necessary to maintain star formation, spiral and bar structure, and secular evolution in galaxies. This can occur through tidal interaction, or mass accretion from cosmic filaments. Different processes will be reviewed to…
The existence of Uranus and Neptune presents severe difficulties for the core accretion model for the formation of ice giant planets. We suggest an alternative mechanism, namely disk instability leading to the formation of gas giant…
Young planets interact with their parent gas disks through tidal torques. An imbalance between inner and outer torques causes bodies of mass $\ga 0.1$ Earth masses to lose angular momentum and migrate inward rapidly relative to the disk;…
We present the results of hydrodynamical simulations of the orbital evolution of planets undergoing runaway gas accretion in radiative discs. We consider accreting disc models with constant mass flux through the disc, and where radiative…
Planets of 1-4 times Earth's size on orbits shorter than 100 days exist around 30-50% of all Sun-like stars. In fact, the Solar System is particularly outstanding in its lack of "hot super-Earths" (or "mini-Neptunes"). These planets -- or…
The formation of the Earth's core is a consequence of planetary accretion and processes in the Earth's interior. The mechanical process of planetary differentiation is likely to occur in large, if not global, magma oceans created by the…
The giant planet occurrence rate rises with orbital period out to at least $\sim$300 days. Large-scale planetary migration through the disk has long been suspected to be the physical origin of this feature, as the timescale of standard Type…
We analyse the potential migration of massive planets forming far away from an inner planetary system. For this, we follow the dynamical evolution of the orbital elements of a massive planet undergoing a dissipative process with a gas disc…
Giant planet formation in the core accretion (CA) paradigm is predicated by the formation of a core, assembled by the coagulation of grains and later by planetesimals within a protoplanetary disc. In contrast, in the disc instability…
In the current galaxy formation scenarios, two physical phenomena are invoked to build disk galaxies: hierarchical mergers and more quiescent external gas accretion, coming from intergalactic filaments. Although both are thought to play a…
Growing planets interact with their natal protoplanetary disc, which exerts a torque onto them allowing them to migrate in the disc. Small mass planets do not affect the gas profile and migrate in the fast type~I migration. Although type~I…
Planets grow via the collisional accretion of small bodies in a protoplanetary disk. Such small bodies feel strong gas drag and their orbits are significantly affected by the gas flow and atmospheric structure around the planet. We…
Close-in giant planets (e.g. ``Hot Jupiters'') are thought to form far from their host stars and migrate inward, through the terrestrial planet zone, via torques with a massive gaseous disk. Here we simulate terrestrial planet growth during…
Several planetary systems are known to host multiple giant planets. However, when two giant planets are accreting from the same disk, it is unclear what effect the presence of the second planet has on the gas accretion process of both…
The Core Accretion model is widely accepted as the primary mechanism for forming planets up to a few Jupiter masses. However, the formation of super-massive planets remains a subject of debate, as their formation via the Core Accretion…
We use a semi-analytic circumstellar disk model that considers movement of the snow line through evolution of accretion and the central star to investigate how gas giant frequency changes with stellar mass. The snow line distance changes…
Giant planet embryos are believed to be spawned by gravitational instability in massive extended (R ~ 100 AU) protostellar discs. In a recent paper we have shown that dust can sediment inside the embryos, as argued earlier by Boss (1998) in…
I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar…
In the last few years, the so-called "Nice model" has got a significant importance in the study of the formation and evolution of the solar system. According to this model, the initial orbital configuration of the giant planets was much…