相关论文: Grain sedimentation inside giant planet embryos

For grain growth to proceed effectively and lead to planet formation a number of barriers to growth must be overcome. One such barrier, relevant for compact grains in the inner regions of the disc, is the `bouncing barrier' in which large…

Ices, including water ice, prefer to recondense onto pre-existing nuclei rather than spontaneously forming grains from a cloud of vapor. Interestingly, different potential recondensation nuclei have very different propensities to actually…

The presence of distant protoplanets may explain the observed gaps in the dust emission of protoplanetary disks. Here, we derive a novel analytical model to describe the temporal decay of the pebble flux through a protoplanetary disk as the…

Circumplanetary disks can be found around forming giant planets, regardless of whether core accretion or gravitational instability built the planet. We carried out state-of-the-art hydrodynamical simulations of the circumplanetary disks for…

Recent work identified a growth barrier for dust coagulation that originates in the electric repulsion between colliding particles. Depending on its charge state, dust material may have the potential to control key processes towards planet…

We examine the predictions of the core accretion - gas capture model concerning the efficiency of planet formation around stars with various masses. First, we follow the evolution of gas and solids from the moment when all solids are in the…

Dust drifting inward in protoplanetary disks is subject to increasing temperatures. In laboratory experiments, we tempered basaltic dust between 873 K and 1273 K and find that the dust grains change in size and composition. These…

There has been disagreement currently about whether cooling in protoplanetary disks can be sufficiently fast to induce the formation of gas giant protoplanets via gravitational instabilities. Simulations by our own group and others indicate…

Context. Observations at sub-millimeter and mm wavelengths will in the near future be able to resolve the radial dependence of the mm spectral slope in circumstellar disks with a resolution of around a few AU at the distance of the closest…

It has been long proposed that, if all the terrestrial planets form within a tiny ring of solid material at around 1 AU, the concentrated mass-distance distribution of the current system can be reproduced. Recent planetesimal formation…

Recent observations of protoplanetary disks have revealed ring-like structures that can be associated to pressure maxima. Pressure maxima are known to be dust collectors and planet migration traps. Most of planet formation works are based…

We consider the lifecycle of dust introduced into the hot interstellar medium in isolated elliptical galaxies. Dust grains are ejected into galactic-scale cooling flows in large ellipticals by normal mass loss from evolving red giants.…

Recent three-dimensional magnetohydrodynamical simulations have identified a disk wind by which gas materials are lost from the surface of a protoplanetary disk, which can significantly alter the evolution of the inner disk and the…

Direct imaging observations constrain the fraction of stars orbited by gas giant planets with separations greater than 10 au to about 0.01 only. This is widely believed to indicate that massive protoplanetary discs rarely fragment on…

Protoplanetary disks are dynamic objects, within which dust grains and gas are expected to be redistributed over large distances. Evidence for this redistribution is seen both in other protoplanetary disks and in our own Solar System, with…

We review the problem of the formation of terrestrial planets, with particular emphasis on the interaction of dynamical and geochemical models. The lifetime of gas around stars in the process of formation is limited to a few million years…

We demonstrate that planet formation via pebble accretion is sensitive to external photoevaporation of the outer disc. In pebble accretion, planets grow by accreting from a flux of solids (pebbles) that radially drift inwards from the…

Observational evidence exists for the formation of gas giant planets on wide orbits around young stars by disk gravitational instability, but the roles of disk instability and core accretion for forming gas giants on shorter period orbits…

It is likely that multiple bodies with masses between those of Mars and Earth ("planetary embryos") formed in the outer planetesimal disk of the solar system. Some of these were likely scattered by the giant planets into orbits with…

The timescales on which astronomical dust grows remain poorly understood, with important consequences for our understanding of processes like circumstellar disk evolution and planet formation.A number of post-asymptotic giant branch stars…