Ion-neutral friction and accretion-driven turbulence in self-gravitating filaments

  title={Ion-neutral friction and accretion-driven turbulence in self-gravitating filaments},
  author={Patrick Hennebelle and Ph. Andr'e},
  journal={Astronomy and Astrophysics},
Recent Herschel observations have confirmed that filaments are ubiquitous in molecular clouds and suggest, that irrespective of the column density, there is a characteristic width of about 0.1 pc whose physical origin remains unclear. We develop an analytical model that can be applied to self-gravitating accreting filaments. It is based on the one hand on the virial equilibrium of the central part of the filament and on the other hand on the energy balance between the turbulence driven by… 

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