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Episodic Magnetic Bubbles and Jets: Astrophysical Implications from Laboratory Experiments

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 نشر من قبل Andrea Ciardi Dr
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف Andrea Ciardi




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Collimated outflows (jets) are ubiquitous in the universe appearing around sources as diverse as protostars and extragalactic supermassive blackholes. Jets are thought to be magnetically collimated, and launched from a magnetized accretion disk surrounding a compact gravitating object. We have developed the first laboratory experiments to address time-dependent, episodic phenomena relevant to the poorly understood jet acceleration and collimation region. The experimental results show the periodic ejections of magnetic bubbles naturally evolving into a heterogeneous jet propagating inside a channel made of self-collimated magnetic cavities. The results provide a unique view of the possible transition from a relatively steady-state jet launching to the observed highly structured outflows.



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