Related papers: Multiplicity in Early Stellar Evolution
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…
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…
Nearby companions alter the evolution of massive stars in binary systems. Using a sample of Galactic massive stars in nearby young clusters, we simultaneously measure all intrinsic binary characteristics relevant to quantify the frequency…
This chapter reviews the dynamical processes in young stellar clusters. The accretion of gas by individual stars affects the dynamics of the cluster, and the masses of the stars. Dynamical mass segregation cannot explain the degree of mass…
We study the formation of massive Population III binary stars using a newly developed radiation hydrodynamics code with the adaptive mesh refinement and adaptive ray-tracing methods. We follow the evolution of a typical primordial…
Characterization of the binary fractions in star clusters is of fundamental importance for many fields in astrophysics. Observations indicate that the majority of stars are found in binary systems, while most stars with masses greater than…
We investigate the formation of binary stellar systems. We consider a model where a `seed' protobinary system forms, via fragmentation, within a collapsing molecular cloud core and evolves to its final mass by accreting material from an…
Observations of young multiple star systems find a bimodal distribution in companion frequency and separation. The origin of these peaks has often been attributed to binary formation via core and disc fragmentation. However, theory and…
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…
Binary populations in young star clusters show multiplicity fractions both lower and up to twice as high as those observed in the Galactic field. We follow the evolution of a population of binary stars in dense and loose star clusters…
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…
We investigate how the multiplicity of binary, triple and quadruple star systems changes as the systems evolve from the zero-age main-sequence to the Hubble time. We find the change in multiplicity fractions over time for each data set,…
The "in-situ" formation of very wide binaries is hard to explain as their physical separations are beyond the typical size of a collapsing cloud core ($\approx$5000-10,000 au). Here we investigate the formation process of such systems. We…
The discovery of multiple stellar populations in globular clusters has implications for all the aspects of the study of these stellar systems. In this paper, by means of N-body simulations, we study the evolution of binary stars in…
It has now been known for over a decade that low-mass stars located in star-forming regions are very frequently members of binary and multiple systems, even more so than main sequence stars in the solar neighborhood. This high multiplicity…
Based on a large number of observations carried out in the last decade it appears that the fraction of stars with protoplanetary disks declines steadily between ~1 Myr and ~10 Myr. We do, however, know that the multiplicity fraction of…
It appears that most stars are born in clusters, and that at birth most stars have circumstellar discs which are comparable in size to the separations between the stars. Interactions between neighbouring stars and discs are therefore likely…
Most stars form in star clusters and stellar associated. To understand the roles of star cluster environments in shaping the dynamical evolution of planetary systems, we carry out direct $N$-body simulations of four planetary systems models…
We postulate that most stars are born in aggregates of binary systems which are dynamically equivalent to the `dominant mode cluster'. The initial binary orbits are consitent with pre-main sequence data. Stellar masses are paired at random…
Stellar obliquities, or spin-orbit angles, prevalent in exoplanet systems, can impose important constraints on their formation and evolution histories. Recent studies suggest that primordial misalignments between protoplanetary disks and…