Star Formation in Molecular Clouds

Abstract

Stars and star clusters form by gravoturbulent fragmentation of interstellar gas clouds. The supersonic turbulence ubiquitously observed in Galactic molecular gas generates strong density fluctuations with gravity taking over in the densest and most massive regions. Collapse sets in to build up stars. Turbulence plays a dual role. On global scales it provides support, while at the same time it can promote local collapse. Stellar birth is thus intimately linked to the dynamical behavior of parental gas cloud, which governs when and where protostars form, and how they contract and grow in mass via accretion from the surrounding cloud material. The thermodynamic behavior of the star forming gas plays a crucial part in this process and influences the stellar mass function as well as the dynamic properties of the nascent stellar cluster. This lecture provides a critical review of our current understand- ing of stellar birth and compares observational data with competing theoretical models.

Invited Lecture held at the Avry Schatzman School "STAR FORMATION IN THE LOCAL UNIVERSE" in Aussois in September 2010, organized by Corinne Charbonnel and Thierry Montmerle (36 pages, 8 figures)

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Cited by in corpus (19)

• An Imprint of Molecular Cloud Magnetization in the Morphology of the Dust Polarized Emission
• Tidal Truncation of Inclined Circumstellar and Circumbinary Discs in Young Stellar Binaries
• LYRA I: Simulating the multi-phase ISM of a dwarf galaxy with variable energy supernovae from individual stars
• Stellar clusters in the inner Galaxy and their correlation with cold dust emission
• Unbound Young Stellar Systems: Star Formation on the loose
• Evolution of linear warps in accretion discs and applications to protoplanetary discs in binaries
• Assembly of Protoplanetary Disks and Inclinations of Circumbinary Planets
• Runaway massive stars as variable gamma-ray sources
• On the Habitability of Universes without Stable Deuterium
• A Corona Australis cloud filament seen in NIR scattered light. III. Modelling and comparison with Herschel sub-millimetre data
• Dynamical origin of non-thermal states in galactic filaments
• Kinematic and Thermal Structure at the onset of high-mass star formation
• Supersonic turbulence in 3D isothermal flow collision
• Star-forming regions of the Aquila rift cloud complex. II. Turbulence in molecular cores probed by NH3 emission
• Dissipative phenomena in extended-bodies interactions I: Methods Dwarf galaxies of the Local Group and their synthetic CMDs
• Photoionization feedback in turbulent molecular clouds
• The structure and kinematics of dense gas in NGC 2068
• A Discontinuous Galerkin Solver in the FLASH Multi-Physics Framework
• Taking control of compressible modes: bulk viscosity and the turbulent dynamo