Related papers: Modelling Star Cluster Formation: Gas Accretion
The mass growth of protostars is a central element to the determination of fundamental stellar population properties such as the initial mass function. Constraining the accretion history of individual protostars is therefore an important…
In this chapter I review theoretical models for the formation of very massive stars. After a brief overview of some relevant observations, I spend the bulk of the chapter describing two possible routes to the formation of very massive…
Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…
We calculate numerically the collapse of slowly rotating, non-magnetic, massive molecular clumps, which conceivably could lead to the formation of massive stars. Because radiative acceleration on dust grains plays a critical role in the…
We review progress in numerical simulations of star cluster formation. These simulations involve the bottom-up assembly of clusters through hierarchical mergers, which produces a fractal stellar distribution at young (~0.5 Myr) ages. The…
The standard picture of accretion is a steady flow of matter from the disc onto the young star - a concept which assumes the star-disc system to be completely isolated. However, in a dense cluster environment star-disc systems do interact…
Like their lower mass siblings, massive protostars can be expected to: a) be surrounded by circumstellar disks and b) launch magnetically-driven jets and outflows. The disk formation and global evolution is thereby controlled by advection…
Galaxies accrete their mass by means of both smooth accretion from the cosmic web, and the mergers of smaller entities. We wish to quantify the respective role of these two modes of accretion, which could determine the morphological types…
Star cluster formation and assembly occurs inside filamentary and turbulent molecular clouds, which imprints both spatial and kinematic substructure on the young cluster. In this paper, we quantify the amount and evolution of this…
We investigate the dynamical evolution of star clusters during their formation, assuming that they are born from a turbulent starless clump of a given mass that is embedded within a parent self-gravitating molecular cloud characterized by a…
Our current understanding of the physical processes of star formation is reviewed, with emphasis on processes occurring in molecular clouds like those observed nearby. The dense cores of these clouds are predicted to undergo gravitational…
We investigate the physics of gas accretion in young stellar clusters. Accretion in clusters is a dynamic phenomenon as both the stars and the gas respond to the same gravitational potential. Accretion rates are highly non-uniform with…
We consider the conditions required for a cluster core to shrink, by adiabatic accretion of gas from the surrounding cluster, to densities such that stellar collisions are a likely outcome. We show that the maximum densities attained, and…
Young stars form on a wide range of scales, producing aggregates and clusters with various degrees of gravitational self-binding. The loose aggregates have a hierarchical structure in both space and time that resembles interstellar…
It has been known for more than 30 years that star formation in giant molecular clouds (GMCs) is slow, in the sense that only ~1% of the gas forms stars every free-fall time. This result is entirely independent of any particular model of…
It is believed that the majority of stars form in clusters. Therefore it is likely that the gas physical conditions that prevail in forming clusters, largely determine the properties of stars that form and in particular the initial mass…
We investigate the impact of different initial conditions for the initial density profile and the initial turbulence on the formation process of protostellar clusters. We study the collapse of dense molecula r cloud cores with…
Population III stars are believed to have been more massive than typical stars today and to have formed in relative isolation. The thermodynamic impact of metals is expected to induce a transition leading to clustered, low-mass Population…
In the earliest phases of their evolution, stars gain mass through the acquisition of matter from their birth clouds. The widely accepted classical concept of early stellar evolution neglects the details of this accretion phase and assumes…
One puzzle in understanding how stars form in clusters is the source of mass -- is all of the mass in place before the first stars are born, or is there an extended period when the cluster accretes material which can continuously fuel the…