Star formation in transient molecular clouds

P C Clark, I A Bonnell

Research output: Contribution to journalArticlepeer-review

37 Citations (Scopus)

Abstract

We present the results of a numerical simulation in which star formation proceeds from an initially unbound molecular cloud core. The turbulent motions, which dominate the dynamics, dissipate in shocks leaving a quiescent region which becomes gravitationally bound and collapses to form a small multiple system. Meanwhile, the bulk of the cloud escapes due to its initial supersonic velocities. In this simulation, the process naturally results in a star formation efficiency of similar to50 per cent. The mass involved in star formation depends on the gas fraction that dissipates sufficient kinetic energy in shocks. Thus, clouds with larger turbulent motions will result in lower star formation efficiencies. This implies that globally unbound, and therefore transient giant molecular clouds (GMCs), can account for the low efficiency of star formation observed in our Galaxy without recourse to magnetic fields or feedback processes. Observations of the dynamic stability in molecular regions suggest that GMCs may not be self-gravitating, supporting the ideas presented in this letter.

Original languageEnglish
Pages (from-to)L36-L40
Number of pages6
JournalMonthly Notices of the Royal Astronomical Society
Volume347
Issue number2
DOIs
Publication statusPublished - 11 Jan 2004

Keywords

  • stars : formation
  • ISM : clouds
  • ISM : kinematics and dynamics
  • ISM : structure
  • TURBULENCE
  • FRAGMENTATION
  • SIMULATIONS
  • CLUSTERS
  • COLLAPSE
  • REGIONS

Fingerprint

Dive into the research topics of 'Star formation in transient molecular clouds'. Together they form a unique fingerprint.

Cite this