Related papers: Gravito-turbulence in irradiated protoplanetary di…
Using local three dimensional radiation hydrodynamics simulations, the nonlinear outcome of gravitational instability in an irradiated protoplanetary disc is investigated in a parameter space of the surface density $\Sigma$ and the radius…
Low mass, self-gravitating accretion disks admit quasi-steady,`gravito-turbulent' states in which cooling balances turbulent viscous heating. However, numerical simulations show that gravito-turbulence cannot be sustained beyond dynamical…
We have investigated the properties of gravito-turbulent discs in 3D using high-resolution shearing-box simulations. For large enough domain sizes, $L_y \gtrsim 60H$, the disc settles down into a quasi-steady state, showing no long term…
Characterizing turbulence in protoplanetary disks is crucial for understanding how they accrete and spawn planets. Recent measurements of spectral line broadening promise to diagnose turbulence, with different lines probing different…
Gravitational instability (GI) features in several aspects of protostellar disk evolution, most notably in angular momentum transport, fragmentation, and the outbursts exemplified by FU Ori and EX Lupi systems. The outer regions of…
Young protoplanetary discs are expected to be gravitationally unstable, which can drive angular momentum transport as well as be a potential mechanism for planet formation. Gravitational instability is most prevalent in the outer disc where…
Young protoplanetary discs and the outer radii of active galactic nucleii may be subject to gravitational instability and, as a consequence, fall into a `gravitoturbulent' state. While in this state, appreciable angular momentum can be…
Gravitational instabilities can drive small-scale turbulence and large-scale spiral arms in massive gaseous disks under conditions of slow radiative cooling. These motions affect the observed disk morphology, its mass accretion rate and…
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…
The dynamics of solid bodies in protoplanetary disks are subject to the properties of any underlying gas turbulence. Turbulence driven by disk self-gravity shows features distinct from those driven by the magnetorotational instability…
High-resolution, 2-D hydrodynamical simulations with a large dynamic range are performed to study the turbulent nature of the interstellar medium (ISM) in galactic disks. The simulations are global, where the self-gravity of the ISM,…
Angular momentum transport within young massive protoplanetary discs may be dominated by self-gravity at radii where the disk is too weakly ionized to allow the development of the magneto-rotational instability. We use time-dependent…
In this paper, the effect of self-gravity on the protoplanetary discs is investigated. The mechanisms of angular momentum transport and energy dissipation are assumed to be the viscosity due to turbulence in the accretion disc. The energy…
Self-gravity becomes competitive as an angular momentum transport process in accretion discs at large radii, where the temperature is low enough that external irradiation likely contributes to the thermal balance. Irradiation is known to…
Given the important role turbulence plays in the settling and growth of dust grains in protoplanetary disks, it is crucial that we determine whether these disks are turbulent and to what extent. Protoplanetary disks are weakly ionized near…
Irradiation from the central star controls the temperature structure in protoplanetary discs. Yet simulations of gravitational instability typically use models of stellar irradiation with varying complexity, or ignore it altogether,…
Gravitational instability is one of considerable mechanisms to explain the formation of giant planets. We study the gravitational stability for the protoplanetary disks around a protostar. The temperature and Toomre's Q-value are calculated…
It has recently been suggested that in the presence of driven turbulence discs may be much less stable against gravitational collapse than their non turbulent analogs, due to stochastic density fluctuations in turbulent flows. This mode of…
In their early stages, protoplanetary discs are sufficiently massive to undergo gravitational instability (GI). This instability is thought to be involved in mass accretion, planet formation via gas fragmentation, the generation of spiral…
The amount of turbulence in protoplanetary discs around young stars is critical for determining the efficiency, timeline, and outcomes of planet formation. It is also difficult to measure. Observations are still limited, but direct…