Observational studies of pre-stellar cores and infrared dark clouds

Abstract

Stars like our Sun and planets like our Earth form in dense regions within interstellar molecular clouds, called pre-stellar cores (PSCs). PSCs provide the initial conditions in the process of star and planet formation. In the past 15 years, detailed observations of (low-mass) PSCs in nearby molecular cloud complexes have allowed us to find that they are cold (T < 10 K) and quiescent (molecular line widths are close to thermal), with a chemistry profoundly affected by molecular freeze-out onto dust grains. In these conditions, deuterated molecules flourish, becoming the best tools to unveil the PSC physical and chemical structure. Despite their apparent simplicity, PSCs still offer puzzles to solve and they are far from being completely understood. For example, what is happening to the gas and dust in their nuclei (the future stellar cradles) is still a mystery that awaits for ALMA. Other important questions are: how do different environments and external conditions affect the PSC physical/chemical structure? Are PSCs in high-mass star forming regions similar to the well-known low-mass PSCs? Here I review observational and theoretical work on PSCs in nearby molecular cloud complexes and the ongoing search and study of massive PSCs embedded in infrared dark clouds (IRDCs), which host the initial conditions for stellar cluster and high-mass star formation.

To appear in the proceedings of IAU Symposium 280: "The Molecular Universe"

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Cited by in corpus (6)

• The TOP-SCOPE survey of Planck Galactic Cold Clumps: Survey overview and results of an exemplar source, PGCC G26.53+0.17
• G11.92-0.61-MM2: A Bonafide Massive Prestellar Core?
• The properties of Planck Galactic cold clumps in the L1495 dark cloud
• Deuterium Fractionation in the Ophiuchus Molecular Cloud
• Imaging polarimetry of the rotating Bok globule CB67
• Polarization fraction of Planck Galactic cold clumps and forecasts for the Simons Observatory