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arXiv · 1312.5760

Formation and collimation of relativistic MHD jets - simulations and radio maps

Christian Fendt·Oliver Porth·Somayeh Sheikhnezami
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Abstract

We present results of magnetohydrodynamic (MHD) simulations of jet formation and propagation, discussing a variety of astrophysical setups. In the first approach we consider simulations of relativistic MHD jet formation, considering jets launched from the surface of a Keplerian disk, demonstrating numerically - for the first time - the self-collimating ability of relativistic MHD jets. We obtain Lorentz factors up to about 10 while acquiring a high degree of collimation of about 1 degree. We then present synchrotron maps calculated from the intrinsic jet structure derived from the MHD jet formation simulation. We finally present (non-relativistic) MHD simulations of jet lauching, treating the transition between accretion and ejection. These setups include a physical magnetic diffusivity which is essential for loading the accretion material onto the outflow. We find relatively high mass fluxes in the outflow, of the order of 20-40 % of the accretion rate.

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Christian Fendt, Oliver Porth, Somayeh Sheikhnezami. 2013-12-20. Formation and collimation of relativistic MHD jets - simulations and radio maps. https://doi.org/10.1142/s2010194514601902

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