Cooling, gravity, and geometry: Flow-driven massive core formation

Journal article

We study numerically the formation of molecular clouds in large-scale colliding flows including self-gravity. The models emphasize the competition between the effects of gravity on global and local scales in an isolated cloud. Global gravity builds up large-scale filaments, while local gravity, triggered by a combination of strong thermal and dynamical instabilities, causes cores to form. The dynamical instabilities give rise to a local focusing of the colliding flows, facilitating the rapid formation of massive protostellar cores of a few hundred M⊙. The forming clouds do not reach an equilibrium state, although the motions within the clouds appear to be comparable to virial. The self-similar core mass distributions derived from models with and without self-gravity indicate that the core mass distribution is set very early on during the cloud formation process, predominantly by a combination of thermal and dynamical instabilities rather than by self-gravity. © 2008. The American Astronomical Society. All rights reserved.

Authors: Heitsch, F; Hartmann, L; Slyz, A; Devriendt, J; Burkert, A

• Publication status: Published
• Publisher: Institute of Physics Publishing
• Journal: ASTROPHYSICAL JOURNAL
• Volume: 674
• Issue: 1
• Pages: 316-328
• Publication date: 2008-02-10
• DOI: 10.1086/523697
• EISSN: 1538-4357
• ISSN: 0004-637X
• Language: English
• Keywords: methods : numerical; gravitation; ISM : clouds; stars : formation; turbulence; instabilities