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Magnetic Fields from Filaments to Cores

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 نشر من قبل Patrick Koch
 تاريخ النشر 2018
  مجال البحث فيزياء
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How important is the magnetic (B-) field when compared to gravity and turbulence in the star-formation process? Does its importance depend on scale and location? We summarize submm dust polarization observations towards the large filamentary infrared dark cloud G34 and towards a dense core in the high-mass star-forming region W51. We detect B-field orientations that are either perpendicular or parallel to the G34 filament axis. These B-field orientations further correlate with local velocity gradients. Towards three cores in G34 we find a varying importance between B-field, gravity, and turbulence that seems to dictate varying types of fragmentation. At highest resolution towards the gravity-dominated collapsing core W51 e2 we resolve new B-field features, such as converging B-field lines and possibly magnetic channels.



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