Related papers: Ring Formation in Protoplanetary Disks Driven by a…
Enhancing the local dust-to-gas ratio in protoplanetary discs is a necessary first step to planetesimal formation. In laminar discs, dust settling is an efficient mechanism to raise the dust-to-gas ratio at the disc midplane. However,…
Previous simulations of self-gravitating protostellar disks have shown that, once developed, gravitational instabilities are enhanced by cooling the disk constantly during its evolution (Pickett et al. 2002). These earlier calculations…
Protoplanetary disk simulations show that a single planet can excite more than one spiral arm, possibly explaining recent observations of multiple spiral arms in some systems. In this paper, we explain the mechanism by which a planet…
Instabilities and strong dynamical interactions between multiple giant planets have been proposed as a possible explanation for the surprising orbital properties of extrasolar planetary systems. In particular, dynamical instabilities seem…
Gravitational scattering between massive planets has been invoked to explain the eccentricity distribution of extrasolar planets. For scattering to occur, the planets must either form in -- or migrate into -- an unstable configuration. In…
We carry out three dimensional radiation hydrodynamical simulations of gravitationally unstable discs using to explore the movement of mass in a disc following its fragmentation. Compared to a more quiescent state before it fragments, the…
In this paper, we calculate simulated scattered light images of a circumstellar disk in which a planet is forming by gravitational instability. The simulated images bear no correlation to the vertically integrated surface density of the…
Protoplanetary discs at certain radii exhibit adverse radial entropy gradients that can drive oscillatory convection (`convective overstability'; COS). The ensuing hydrodynamical activity may reshape the radial thermal structure of the disc…
Instabilities and strong dynamical interactions between several giant planets have been proposed as a possible explanation for the surprising orbital properties of extrasolar planetary systems. In particular, dynamical instabilities would…
The existence of partially ionized, diffuse gas and dust clouds at kiloparsec scale distances above the central planes of edge-on, galaxy discs was an unexpected discovery about 20 yrs ago. Subsequent observations showed that this EDIG…
We carry out a general study of the stability of astrophysical flows that appear steady in a uniformly rotating frame. Such a flow might correspond to a stellar pulsation mode or an accretion disk with a free global distortion giving it…
Combining hydrodynamic planet-disk interaction simulations with dust evolution models, we show that protoplanetary disks having a giant planet can reveal diverse morphology in (sub-)millimeter continuum, including a full disk without…
Binary systems exert a gravitational torque on misaligned discs orbiting them, causing differential precession which may produce disc warping and tearing. While this is well understood for gas-only discs, misaligned cirumbinary discs of gas…
The formation and evolution of a circumstellar disk in magnetized cloud cores is investigated from prestellar core stage until sim 10^4 yr after protostar formation. In the circumstellar disk, fragmentation first occurs due to gravitational…
The inner edge of the dead zone in protoplanetary disks has been shown to periodically go unstable, leading to accretion outbursts and annular substructure within the dead zone. While dust opacities play a key role in this process, the…
We carry out a two-dimensional, compressible, simulation of a disk, including dust particles, to study the formation and role of vortices in protoplanetary disks. We find that anticyclonic vortices can form out of an initial random…
Recent observations of protoplanetary disks (PPDs) in the sub-mm have revealed the ubiquity of annular substructures, indicative of pebble-sized dust particles trapped in turbulent ring-like gas pressure bumps. This major paradigm shift…
For a long time, gravitational instability in the disk of planetesimals has been suspected to be the main engine responsible for the beginning of dust growth, its advantage being that it provides for rapid growth. Its real importance in…
In protoplanetary disks the aerodynamical friction between particles and gas induces a variety of instabilities that facilitate planet formation. Of these we examine the so-called `secular gravitational instability' (SGI) in the two-fluid…
The formation of circumplanetary disks is central to our understanding of giant planet formation, influencing their growth rate during the post-runaway phase and observability while embedded in protoplanetary disks. We use 3D global…