The physics and modes of star cluster formation: simulations

Abstract

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 resulting clusters are predicted to be mildly aspherical and highly mass-segregated, except in the immediate aftermath of mergers. The upper initial mass function within individual clusters is generally somewhat flatter than for the aggregate population. Recent work has begun to clarify the factors that control the mean stellar mass in a star-forming cloud and also the efficiency of star formation. The former is sensitive to the thermal properties of the gas while the latter depends both on the magnetic field and the initial degree of gravitational boundedness of the natal cloud. Unmagnetized clouds that are initially bound undergo rapid collapse, which is difficult to reverse by ionization feedback or stellar winds.

21 pages, 10 figures. To appear as invited review article in a special issue of the Phil. Trans. Royal Soc. A: Ch. 3 "Star clusters as tracers of galactic star-formation histories" (ed. R. de Grijs). Fully peer reviewed. LaTeX, requires rspublic.cls style file

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Cited by in corpus (14)

• The physics and modes of star cluster formation: observations
• Core-Halo Age Gradients and Star Formation in the Orion Nebula and NGC~2024 Young Stellar Clusters
• Surviving infant mortality in the hierarchical merging scenario
• 3D Morphology of Open Clusters in the Solar Neighborhood with Gaia EDR3 II: Hierarchical Star Formation Revealed by Spatial and Kinematic Substructures
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• Mass and luminosity evolution of young stellar objects
• Star formation in dense clusters
• Young and intermediate-age massive star clusters
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• Star cluster dynamics
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