Related papers: Flybys in protoplanetary discs: II. Observational …
Proto-planetary disc surveys conducted with ALMA are measuring disc radii in multiple star forming regions. The disc radius is a fundamental quantity to diagnose whether discs undergo viscous spreading, discriminating between viscosity or…
One of the striking discoveries of protoplanetary disc research in recent years are the spiral arms seen in several transitional discs in polarised scattered light. An interesting interpretation of the observed spiral features is that they…
Photoevaporative disc winds play a key role in our understanding of circumstellar disc evolution, especially in the final stages, and they might affect the planet formation process and the final location of planets. The study of transition…
Gravitational forces are expected to excite spiral density waves in protoplanetary disks, disks of gas and dust orbiting young stars. However, previous observations that showed spiral structure were not able to probe disk midplanes, where…
We identify a new hydrodynamical instability in protoplanetary discs that may arise due to variations in the dust-to-gas ratio and may lead to concentration of dust grains within a disc. The instability can arise due to dust settling, which…
Some circumstellar disks are observed to show prominent spiral arms in infrared scattered light or (sub-)millimeter dust continuum. The spirals might be formed from self-gravity, shadows, or planet-disk interactions. Recently, it was…
Most stars form in a cluster environment. These stars are initially surrounded by discs from which potentially planetary systems form. Of all cluster environments starburst clusters are probably the most hostile for planetary systems in our…
The expectation that aerodynamic drag will force the solids in a gas-rich protoplanetary disk to spiral in toward the host star on short timescales is one of the fundamental problems in planet formation theory. The nominal efficiency of…
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…
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…
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…
Recent observations of protoplanetary discs reveal disc substructures potentially caused by embedded planets. We investigate how the gas surface density in discs changes the observed morphology in scattered light and dust continuum…
Accretion onto protostars may occur in sharp bursts. Accretion bursts during the embedded phase of young protostars are probably most intense, but can only be inferred indirectly through long-wavelength observations. We perform radiative…
Dust particles in protoplanetary disks, lacking support from pressure, rotate at velocities exceeding those of the surrounding gas. Consequently, they experience a head-wind from the gas that drives them toward the central star. Radial…
Context: Planets are formed amidst young circumstellar disks of gas and dust. The latter is traced by thermal radiation, where strong asymmetric clumps were observed in a handful of cases. These dust traps could be key to understand the…
The formation and early evolution of circumstellar discs often occurs within dense, newborn stellar clusters. For the first time, we apply the moving-mesh code AREPO, to circumstellar discs in 3-D, focusing on disc-disc interactions that…
It is expected that an average protostar will undergo at least one impulsive interaction with a neighbouring protostar whilst a large fraction of its mass is still in a massive, extended disc. Such interactions must have a significant…
Most stars are born in the crowded environments of gradually forming star clusters. Dynamical interactions between close-passing stars and the evolving UV radiation fields from proximate massive stars are expected to sculpt the…
The majority of stars are born in clustered environments. In these environments, close encounters between young stars with planet-forming disks are expected to occur frequently. However, direct evidence of such interactions remains rare.…
The majority of stars are part of gravitationally bound stellar systems, such as binaries. Observations of protobinary systems constrain the conditions that lead to stellar multiplicity and subsequent orbital evolution. We report…