Related papers: Protostellar spin-up and fast rotator formation th…
Binary stars form from the same parent molecular cloud and thus have the same chemical composition. Forming planets take building material (solids) away from the surrounding protoplanetary disc. Assuming that the disc's accretion onto the…
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…
Although the association of gamma-ray bursts with massive stellar death is on firm footing, the nature of the progenitor system and the key ingredients required for a massive star to produce a gamma-ray burst remain open questions. Here, we…
Multiple systems play an important role in the evolution of star clusters. First we discuss several formation mechanisms which depend on the presence of binaries, either primordial or of dynamical origin. Hierarchical configurations are…
Recent observations have suggested that circumstellar disks may commonly form around young stellar objects. Although the formation of circumstellar disks can be a natural result of the conservation of angular momentum in the parent cloud,…
Planet Planet scattering is a leading dynamical mechanism invoked to explain the present orbital distribution of exoplanets. Many stars belong to binary systems, therefore it is important to understand how this mechanism works in presence…
The formation of a star is a dynamic process fed by the gravitational collapse of a molecular cloud core. Theoretical models and observations suggest that the majority of this infalling material settles into a protoplanetary disk before…
The evolution of a protostellar binary system is investigated while it is embedded in its parent molecular cloud core and acted upon by gas drag due to dynamical friction. Approximate analytical results are obtained for the energy and…
Planet formation via core accretion involves the growth of solids that can accumulate to form planetary cores. There are a number of barriers to the collisional growth of solids in protostellar discs, one of which is the drift, or metre,…
More than half of stars reside in binary or multiple star systems and many planets have been found in binary systems. From theoretical point of view, however, whether or not the planetary formation proceeds in a binary system is a very…
Either bulk rotation or local turbulence is widely invoked to drive fragmentation in collapsing cores so as to produce multiple star systems. Even when the two mechanisms predict different manners in which the stellar spins and orbits are…
Since their formation, stars slow down their rotation rates by the removal of angular momentum from their surfaces, e.g. via stellar winds. Despite the complexity of the processes involved, a traditional model, where the removal of angular…
Magnetic fields play a crucial role at all stages of the formation of low mass stars and planetary systems. In the final stages, in particular, they control the kinematics of in-falling gas from circumstellar discs, and the launching and…
Binary systems are very common among field stars. While this relatively small number of planets in binaries is probably partly due to strong observational biases, there is, however, statistical evidence that planets are indeed less frequent…
Pulsars may either be spun up or down by hydrodynamic instabilities during the supernova explosion of massive stars. Besides rapidly-rotating cases related to bipolar explosions, stellar rotation may affect the explosion of massive stars in…
It is believed that the radio pulsars rotating at spin periods of about 30 millisecond or even lower got such high spins through the transfer of angular momentum by accreting matter from their binary companions (or past companions) in the…
We present the latest development of the disk gravitational instability and fragmentation model, originally introduced by us to explain episodic accretion bursts in the early stages of star formation. Using our numerical hydrodynamics model…
Utilizing a series of N-body simulations, we argue that gravitationally bound stellar clusters of modest population evolve very differently from the picture presented by classical dynamical relaxation theory. The system's most massive stars…
A 2D dynamic model is utilized to investigate star formation in rotating filamentary molecular clouds (FMCs) amidst magnetic fields. The study reveals that the emergence of field stars is possible under both weak and strong magnetic fields…
Most stars form in a clustered environment. Therefore, it is important to assess how this environment influences the evolution of protoplanetary discs around young stars. In turn, this affects their ability to produce planets and ultimately…