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A 3D simulation of a non-relativistic, magnetically driven jet propagating in a stratified atmosphere is presented, covering about three decades in distance and two decades in sideways expansion. The simulation captures the jet acceleration through the critical surfaces and the development of (kink-)instabilities driven by the free energy in the toroidal magnetic field component. The instabilities destroy the ordered helical structure of the magnetic field, dissipating the toroidal field energy on a length scale of about 2-15 times the Alfven distance. We compare the results with a 2.5D (axisymmetric) simulation, which does not become unstable. The acceleration of the flow is found to be quite similar in both cases, but the mechanisms of acceleration differ. In the 2.5D case approximately 20% of the Poynting flux remains in the flow, in the 3D case this fraction is largely dissipated internally. Half of the dissipated energy is available for light emission; the resulting radiation would produce structures resembling those seen in protostellar jets.
We present experimental results on the formation of supersonic, radiatively cooled jets driven by pressure due to the toroidal magnetic field generated by the 1.5 MA, 250 ns current from the MAGPIE generator. The morphology of the jet produced in the
Several observations of astrophysical jets show evidence of a structure in the direction perpendicular to the jet axis, leading to the development of spine & sheath models of jets. Most studies focus on a two-component jet consisting of a highly rela
We explore the poloidal structure of two-dimensional (2D) MHD winds in relation to their potential association with the X-ray warm absorbers (WAs) and the highly-ionized ultra-fast outflows (UFOs) in AGN, in a single unifying approach. We present the
The properties of relativistic jets, their interaction with the ambient environment, and particle acceleration due to kinetic instabilities are studied self-consistently with Particle-in-Cell simulations. An important key issue is how a toroidal magn
Jets and pulsar-fed supernova remnants (plerions) tend to develop highly organized toroidal magnetic field. Such a field structure could explain the polarization properties of some jets, and contribute to their lateral confinement. A toroidal field g