Related papers: Stellar Encounters: A Stimulus for Disc Fragmentat…
Theory and simulations suggest that it is possible to form low-mass hydrogen-burning stars, brown dwarfs and planetary-mass objects via disc fragmentation. As disc fragmentation results in the formation of several bodies at comparable…
We investigate how a protoplanetary disc's susceptibility to gravitational instabilities and fragmentation depends on the mass of its host star. We use 1D disc models in conjunction with 3D SPH simulations to determine the critical…
Investigations of stellar encounters in cluster environments have demonstrated their potential influence on the mass and angular momentum of protoplanetary discs around young stars. In this study it is investigated in how far the initial…
In multiple stellar systems interactions among the companion stars and their discs affect planet formation. In the circumstellar case tidal truncation makes protoplanetary discs smaller, fainter and less long-lived than those evolving in…
Circumstellar disks in binaries are perturbed by the companion gravity causing significant alterations of the disk morphology. Spiral waves due to the companion tidal force also develop in the vertical direction and affect the disk…
Most stars are born in clusters and the resulting gravitational interactions between cluster members may significantly affect the evolution of circumstellar discs and therefore the formation of planets and brown dwarfs. Recent findings…
Binarity in massive stars has proven to be an important aspect in the their evolution. For Be stars, it might be the cause of their spin up, and thus part of the mechanism behind the formation of their viscous decretion disks. Detecting…
We present three-dimensional self-gravitating smoothed-particle hydrodynamics (SPH) simulations of an isothermal gaseous disc interacting with an embedded planet. Discs of varying stability are simulated with planets ranging from 10…
Theory and observations suggest that star formation occurs hierarchically due to the fragmentation of giant molecular clouds. In this case we would expect substructure and enhanced stellar multiplicity in the primordial cluster. This…
Depending on the stellar densities, protoplanetary discs in stellar clusters undergo background heating, disc truncation-driven by stellar encounter, and photo-evaporation. Disc truncation leads to reduced characteristic sizes and disc…
Most stars form in embedded clusters. Stellar flybys may affect the orbital architecture of the systems by exciting the eccentricity and causing dynamical instability. Since, incidentally, the timescale over which a cluster loses its…
Thermodynamics play an important role in determining the way a protostellar disc fragments to form planets, brown dwarfs and low-mass stars. We explore the effect that different treatments of radiative transfer have in simulations of…
Recent analyses have shown that close encounters between stars and stellar black holes occur frequently in dense star clusters. Depending upon the distance at closest approach, these interactions can lead to dissipating encounters such as…
We perform SPH simulations of the collapse and fragmentation of low-mass cores having different initial levels of turbulence (alpha_turb=0.05,0.10,0.25). We use a new treatment of the energy equation which captures the transport of cooling…
Protostellar discs may become massive enough to fragment producing secondary low-mass objects: planets, brown dwarfs and low-mass stars. We study the effect of radiative feedback from such newly-formed secondary objects using radiative…
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 present results from the first population synthesis study of protostellar discs. We analyse the evolution and properties of a large sample of protostellar discs formed in a radiation hydrodynamical simulation of star cluster formation.…
We investigate the dynamical effects of an interaction between an initially barred galaxy and a small spherical companion using an N-body/SPH algorithm. In the models described here the small companion passes through the disc of the larger…
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…
(Edited) Many fast rotator stars (rotation periods of < 2 days) are found in unresolved binaries with separations of tens of au. This correlation leads to the question of whether the formation of binary stars inherently produces fast…