A dynamical model for the dusty ring in the Coalsack

  title={A dynamical model for the dusty ring in the Coalsack},
  author={Patrick Hennebelle and Anthony Peter Whitworth and Simon P. Goodwin},
  journal={Astronomy and Astrophysics},
Lada et al. recently presented a detailed near-infrared extinction map of Globule G2 in the Coalsack molecular cloud complex, showing that this starless core has a well-defined central extinction minimum. We propose a model for G2 in which a rapid increase in external pressure is driving an approximately symmetric compression wave into the core. The rapid increase in external pressure could arise because the core has recently been assimilated by the Coalsack cloud complex, or because the… Expand

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