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Accretion and Diffusion Timescales in Sheets and Filaments

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 نشر من قبل Fabian Heitsch
 تاريخ النشر 2014
  مجال البحث فيزياء
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 تأليف Fabian Heitsch




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A comparison of accretion and (turbulent) magnetic diffusion timescales for sheets and filaments demonstrates that dense star-forming clouds generally will -- under realistic conditions -- become supercritical due to mass accretion on timescales at least an order of magnitude shorter than ambipolar and/or turbulent diffusion timescales. Thus, ambipolar or turbulent diffusion -- while present -- is unlikely to control the formation of cores and stars.

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