Cold Dark Clouds: The Initial Conditions for Star Formation

Abstract

Cold dark clouds are nearby members of the densest and coldest phase in the galactic interstellar medium, and represent the most accessible sites where stars like our Sun are currently being born. In this review we discuss recent progress in their study, including the newly discovered infrared dark clouds that are likely precursors to stellar clusters. At large scales, dark clouds present filamentary mass distributions with motions dominated by supersonic turbulence. At small, sub-parsec scales, a population of subsonic starless cores provides a unique glimpse of the conditions prior to stellar birth. Recent studies of starless cores reveal a combination of simple physical properties together with a complex chemical structure dominated by the freeze-out of molecules onto cold dust grains. Elucidating this combined structure is both an observational and theoretical challenge whose solution will bring us closer to understanding how molecular gas condenses to form stars.

BIG... 61 pages, 13 figures, to appear in ARAA Vol. 45 in press

References in corpus (1)

• Theory of Star Formation

Cited by in corpus (8)

• Theory of Star Formation
• Filamentary structure of star-forming complexes
• The structures of embedded clusters in the Perseus, Serpens and Ophiuchus molecular clouds
• A Molecular Line Observation toward Massive Clumps Associated with Infrared Dark Clouds
• Protostar Formation in Supersonic Flows: Growth and Collapse of Spherical Cores
• The Fractal Distribution of HII Regions in Disk Galaxies
• Spitzer Observations of L429: A Near-collapse or Collapsing Starless Core
• Studies of Dense Cores with ALMA