Related papers: Constraint on the giant planet production by core …
We use a multiannulus planetesimal accretion code to investigate the growth of icy planets in the outer regions of a planetesimal disk. In a quiescent minimum mass solar nebula, icy planets grow to sizes of 1000--3000 km on a timescale t =…
The formation of cold gas giants similar to Jupiter and Saturn in orbit and mass is a great challenge for planetesimal-driven core accretion models because the core growth rates far from the star are low. Here we model the growth and…
We investigate the occurrence of accretion bursts, dust accumulation, and the prospects for planetesimal formation in a gravitationally unstable magnetized protoplanetary disk with globally suppressed but episodically triggered…
We compute the accretion efficiency of small solids, with radii 1 cm $\le$ Rs $\le$ 10 m, on planets embedded in gaseous disks. Planets have masses 3 $\le$ Mp $\le$ 20 Earth masses (Me) and orbit within 10 AU of a solar-mass star. Disk…
In the core-accretion model, gas-giant planets form solid cores which then accrete gaseous envelopes. Tidal interactions with disk gas cause a core to undergo inward type-I migration in 10^4 to 10^5 years. Cores must form faster than this…
The core-accretion and disk instability models have so far been used to explain planetary formation. These models have different conditions, such as planet mass, disk mass, and metallicity for formation of gas giants. The core-accretion…
The observed lifetimes of gaseous protoplanetary discs place strong constraints on gas and ice giant formation in the core accretion scenario. The approximately 10-Earth-mass solid core responsible for the attraction of the gaseous envelope…
Aims. In the context of the core instability model, we present calculations of in situ giant planet formation. The oligarchic growth regime of solid protoplanets is the model adopted for the growth of the core. Methods. The full…
We present two-dimensional hydrodynamic simulations of self-gravitating protostellar disks subject to axisymmetric infall from envelopes and irradiation from the central star, to explore disk fragmentation due to gravitational instability…
Gravitational instability has been invoked as a possible mechanism of giant planet formation in protoplanetary disks. Here we critically revise its viability by noting that for the direct production of giant planets it is not enough for…
We numerically investigate under which conditions the planet detected at 2.1 AU of Gamma-Cephei could form through the core-accretion scenario despite the perturbing presence of the highly eccentric companion star. We first show that the…
We study quasi-static atmospheres of accreting protoplanetary cores for different opacity behaviors and realistic planetesimal accretion rates in various parts of protoplanetary nebula. Atmospheres segregate into those having outer…
I examine the standard model of planet formation, including pebble accretion, using numerical simulations. Planetary embryos large enough to become giant planets do not form beyond the ice line within a typical disk lifetime unless icy…
Runaway growth ends when the largest protoplanets dominate the dynamics of the planetesimal disk; the subsequent self-limiting accretion mode is referred to as ``oligarchic growth.'' Here, we begin by expanding on the existing analytic…
To date, there is no core accretion simulation that can successfully account for the formation of Uranus or Neptune within the observed 2-3 Myr lifetimes of protoplanetary disks. Since solid accretion rate is directly proportional to the…
Context: Pebble accretion is expected to be the dominant process for the formation of massive solid planets, such as the cores of giant planets and super-Earths. So, far, this process has been studied under the assumption that dust…
We propose a pebble-driven core accretion scenario to explain the formation of giant planets around the late-M dwarfs of $M_{\star}{=}0.1{-}0.2 \ M_{\odot}$. In order to explore the optimal disk conditions for giant planet, we perform…
We review the current theoretical understanding how growth from micro-meter sized dust to massive giant planets occurs in disks around young stars. After introducing a number of observational constraints from the solar system, from observed…
We develop a simple model for computing planetary formation based on the core instability model for the gas accretion and the oligarchic growth regime for the accretion of the solid core. In this model several planets can form…
Existence of planets is binaries with relatively small separations (around 20 AU), such as \alpha Centauri or \gamma Cephei poses severe challenges to standard planet formation theories. The problem lies in the vigorous secular excitation…