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Joint Astrophysics Colloquium
Filaments, Cores, and Protostellar Collapse Jason Fiege CITA Magnetic fields play an important role on many scales that are relevant to star formation. Polarization maps in the sub-millimetre reveal highly ordered magnetic fields threading star-forming regions. We discuss models of filamentary molecular clouds and cores, and predict their resulting polarization patterns. These models are compared with new polarization maps of several cores in the Orion B molecular cloud, as well as other maps from the literature. Ultimately, cores collapse to form stars. We discuss a new self-similar model for the time-dependent and non-isotropic collapse of a magnetized, self-gravitating core. Bipolar outflows are generated as infalling material is deflected toward the symmetry axis by poloidal pressure gradients. Remarkably, this model is an exact solution, which can be expressed in closed analytical form.
Thursday, February 8th 2001, 12:30 |