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arXiv · astro-ph/0212291

Collimation of a Central Wind by a Disk-Associated Magnetic Field

S. Matt·R. M. Winglee·K. -H. Bohm
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Abstract

We present the results of time-dependent, numerical magnetohydrodynamic simulations of a realistic young stellar object outflow model with the addition of a disk-associated magnetic field. The outflow produced by the magnetic star-disk interaction consists of an episodic jet plus a wide-angle wind with an outflow speed comparable to that of the jet (100--200 km/s). An initially vertical field of << 0.1 Gauss, embedded in the disk, has little effect on the wind launching mechanism, but we show that it collimates the entire flow (jet + wide wind) at large (several AU) distances. The collimation does not depend on the polarity of the vertical field. We also discuss the possible origin of the disk-associated field.

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S. Matt, R. M. Winglee, K. -H. Bohm. 2002-12-12. Collimation of a Central Wind by a Disk-Associated Magnetic Field. https://doi.org/10.1046/j.1365-8711.2003.06977.x

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