We report 3D SPH and 2D fixed grid simulations of massive protoplanetary discs fed by external mass deposition. We find that systems in which catastrophic disc fragmentation is triggered exhibit very complex dynamics of multiple fragments interacting with each other and with the disc. We find these systems to be natural birth places of binary/multiple stellar systems AND of free floating...
I will show how to use Gaia astrometry to indentify binaries and companions in Young Stars. I will exemplify the power of this technique with a few science cases, from newly identified protoplanets within protoplanetary disks to a reassesment of the multiplicity of the populations of circumbinary and transition disks. I will conclude looking forward to the upcoming Gaia DR4 and the revolution...
Most stars form within dense stellar clusters and reside in binary systems, where circumbinary discs of gas and dust commonly envelop the binary pair. Observations reveal frequent misalignments between these discs and the binary orbital plane. Over time, such misaligned circumbinary discs dynamically evolve toward either coplanar or polar (perpendicular to the binary plane) configurations....
Multiwavelength and time-variable observations of circumbinary disks and their inner cavities have been made possible thanks to recent advancements in interferometry with ALMA and the VLTI instruments. These disks show large, eccentric cavities whose properties depend on the disk's aspect ratio, viscosity, binary eccentricity and mass ratio. Recent studies show that radiative cooling...
