Jets and Outflows from Collapsing Objects

  • Robi BanerjeeEmail author
Part of the Lecture Notes in Physics book series (LNP, volume 791)


Jets and outflows are ubiquitously observed around young stellar objects. There is now strong evidence that these jets are launched from the protostellar disc around the young stars through the coupling of magnetic fields. Magnetic fields threading the pre-stellar molecular cores are dragged inwards during the gravitational collapse and are wound up by the rotating gas in the protostellar disc. The resulting geometry of the magnetic field is that of a hourglass. The magnetic flux is strongly compressed inside the central region and flux lines pointing outwards connecting to the outer region. Additionally, the magnetic field lines anchored to the underlying protodisc are wound up and acquire a strong toroidal component. Such a field configuration, together with the underlying rotor, is known to launch and accelerate material off the disc. This could be the onset of the observed jets around young stellar objects.

In this contribution to the Jetset lecture notes we summarise the research progress in the field of jet launching from collapsing objects. Complying with this workshop on high-performance computing in astrophysics this is done while focusing on results from numerical simulations for this task.


Star Formation Shock Front Smooth Particle Hydrodynamic Accretion Disc Smooth Particle Hydrodynamic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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I thank the JETSET Network which gave me the opportunity to present this lecture. I also thank the organisers of the 5th Jetset workshop for their hospitality. I am funded by the Deutsche Forschungsgemeinschaft within the Emmy-Noether grant BA 3706/1.


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© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  1. 1.Institute for Theoretical Astrophysics at the Zentrum für Astronomie of the University HeidelbergHeidlbergGermany

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