Related papers: The influence of infall on the properties of proto…
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,…
We study the three-dimensional evolution of a viscous protoplanetary disc which accretes gas material from a second protoplanetary disc during a close encounter in an embedded star cluster. The aim is to investigate the capability of the…
In recent years, it has been demonstrated that massive stars see their infant circumstellar medium shaped into a large, irradiated, gravitationally unstable accretion disc during their early formation phase. Such discs constitute the gas…
We study the structure and evolution of the very early protostellar disk (``protodisk'') just after protostar formation, where disk self-gravity dominates and the stellar contribution is dynamically minor. The disk redistributes angular…
We discuss the factors influencing the formation and gravitational fragmentation of protostellar discs. We start with a review of how observations of prestellar cores can be analysed statistically to yield plausible initial conditions for…
We investigate the formation and evolution of "primordial" dusty rings occurring in the inner regions of protoplanetary discs, with the help of long-term, coupled dust-gas, magnetohydrodynamic simulations. The simulations are global and…
While numerical simulations have been playing a key role in the studies of planet-disk interaction, testing numerical results against observations has been limited so far. With the two directly imaged protoplanets embedded in its…
One mechanism for the external destruction of protoplanetary discs in young dense clusters is tidal disruption during the flyby of another cluster member. The degree of mass loss in such an encounter depends, among other parameters, on the…
We investigate the formation of discs within binary systems where at least one component has left the main sequence. In particular we calculate the occurrence rates of systems which can host long-lived, massive discs that may be able to…
The statistical properties of circumstellar disks around young stars are important for constraining theoretical models for the formation and early evolution of planetary systems. In this brief review, I survey the literature related to…
The final stages of a protoplanetary disk are essential for our understanding of the formation and evolution of planets. Photoevaporation is an important mechanism that contributes to the dispersal of an accretion disk and has significant…
Most stars do not form in isolation, but as part of a star cluster or association. These young stars are initially surrounded by protoplanetary discs. In these cluster environments tidal interactions with other cluster members can alter the…
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 the simulation of protoplanetary disc with a power law density profile a disc instability is detected. The instability arises only with a power law profile and is affected by power index. Thus the impact of initial density profile is…
We present first results of our simulations of magnetic fields in the formation of single and binary stars using a recently developed method for incorporating Magnetohydrodynamics (MHD) into the Smoothed Particle Hydrodynamics (SPH) method.…
Disc fragmentation plays an important role in determining the number of primordial stars (Pop III stars), their masses, and hence the initial mass function. In this second paper of a series, we explore the effect of uniform FUV…
Young protostellar discs are likely to be both self-gravitating, and to support grain growth to sizes where the particles decoupled from the gas. This combination could lead to short-wavelength fragmentation of the solid component in…
Discs of gas and dust are ubiquitous around protostars. Hypothetical disc viscosity is thought to cause the gas and dust to accrete onto the star. Turbulence within the disc might be the source of this disc viscosity. However, observed…
The stellar birth environment can significantly shorten protoplanetary disc (PPD) lifetimes due to the influence of stellar feedback mechanisms. The degree to which these mechanisms suppress the time and mass available for planet formation…
Formation, evolution, and dispersal processes of protoplanetary disks are investigated and the disk lifetime is estimated. Gravitational collapse of a pre-stellar core forms both a central star and a protoplanetary disk. The central star…