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arXiv · 1905.07935

Magnetized Gas Collimation of Interstellar Outflow Scaled by Laser-produced Plasma

Tao Tao·Guangyue Hu·Ruxin Li·Zhizhan Xu·Jian Zheng
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Abstract

Young stellar objects/planetary nebula outflow anisotropies usually involve wind-wind interactions and magnetic collimation, but detailed structures of wind and magnetic fields inside collimation region remain undetermined. We numerically investigated its laboratory counterpart, based on poloidal field collimation in magnetocentrifugal launching model. Our analog consist of fast wind: Aluminum plasma generated by laser and magnetized ambient: molecular Helium and B=5-60 Tesla embedded field. Elevating magnetic field strength or decreasing gas density can alter expansion morphology, from sphere to prolonged cavity and ultimately to collimated jet. Outflow patterns can be quantitatively predicted based on the knowledge of its surroundings through a set of external Mach numbers. We conclude that such mixed gas and magnetic field dynamics are consistent with astronomical observations of protostars and planetary nebulae in certain evolution stages, and here provide a scalable framework allowing fitting of flow-field structures in astronomical unresolved regions by assuming their possible geometries on a repeatable laboratory platform.

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Tao Tao, Guangyue Hu, Ruxin Li, Zhizhan Xu, Jian Zheng. 2019-05-20. Magnetized Gas Collimation of Interstellar Outflow Scaled by Laser-produced Plasma. https://arxiv.org/abs/1905.07935

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