相关论文: Parameter Study of Star-Discs Encounters
Young protostellar discs provide the initial conditions for planet formation. The properties of these discs may be different from those of late-phase (T Tauri) discs due to continuing infall from the envelope and protostellar variability…
Aims: At intermediate redshift, galaxy groups/clusters are thought to impact galaxies (e.g. their angular momentum). We investigate whether the environment has an impact on the galaxies' angular momentum and identify underlying driving…
A detailed understanding of the physics of star and planet formation requires study of individual objects as well as statistical assessment of global properties and evolutionary trends. Observational investigations of circumstellar material…
Self-gravitating protostellar discs are unstable to fragmentation if the gas can cool on a time scale that is short compared to the orbital period. We use a combination of hydrodynamic simulations and N-body orbit integrations to study the…
Be stars are surrounded by outflowing circumstellar matter structured in the form of decretion discs. They are often members of binary systems, where it is expected that the decretion disc interacts both radiatively and gravitationally with…
As planets form and grow within gaseous protoplanetary disks, the mutual gravitational interaction between the disk and planet leads to the exchange of angular momentum, and migration of the planet. We review current understanding of…
We investigate the relation between disk mass and mass accretion rate to constrain the mechanism of angular momentum transport in protoplanetary disks. Dust mass and mass accretion rate in Chamaeleon I are correlated with a slope close to…
We study the internal response of a galaxy to an unbound encounter and present a survey of orbital parameters covering typical encounters in different galactic environments. Overall, we conclude that relatively weak encounters by low-mass…
We investigate the evolution of a multi--planet--disc system orbiting one component of a binary star system. The planet--disc system is initially coplanar but misaligned to the binary orbital plane. The planets are assumed to be giants that…
The dynamical interactions that occur in newly formed planetary systems may reflect the conditions occurring in the protoplanetary disk out of which they formed. With this in mind, we explore the attainment and maintenance of orbital…
We present a parameter study of the possibility of tidally triggered disk instability. Using a restricted N-body model which allows for a survey of an extended parameter space, we show that a passing dwarf star with a mass between 0.1 and 1…
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…
We use N-body/hydrodynamic simulations to study the evolution of the spin of a Milky Way-like galaxy through interactions. We perform a controlled experiment of co-planner galaxy-galaxy encounters and study the evolution of disk spins of…
We investigate how the formation and structure of circumplanetary disks (CPDs) varies with planet mass and protoplanetary disk aspect ratio. Using static mesh refinement and a near-isothermal equation of state, we perform a small parameter…
Structures observed in debris disks may be caused by gravitational interaction with planetary or stellar companions. These perturbed disks are often thought to indicate the presence of planets and offer insights into the properties of both…
Most stars are born in dense stellar environments where the formation and early evolution of planetary systems may be significantly perturbed by encounters with neighbouring stars. To investigate on the fate of circumstellar gas disks and…
Results are presented on component masses and system angular momenta for over a hundred low-temperature contact binaries. It is found that the secondary components in close binary systems are very similar in mass. Our observational evidence…
We carry out three-dimensional hydrodynamical simulations to study planet-disc interactions for inclined high mass planets, focusing on the disc's secular evolution induced by the planet. We find that, when the planet is massive enough and…
The recently discovered exoplanets in binary or higher-order multiple stellar systems sparked a new interest in the study of proto-planetary discs in stellar aggregations. Here we focus on disc solids, as they make up the reservoir out of…
Solid material in protoplanetary discs will suffer one of two fates after the epoch of planet formation; either being bound up into planetary bodies, or remaining in smaller planetesimals to be ground into dust. These end states are…