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The role of kink instability in Poynting-flux dominated jets

Dimitrios Giannios·Henk C. Spruit
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Abstract

The role of kink instability in magnetically driven jets is explored through numerical one-dimensional steady relativistic MHD calculations. The instability is shown to have enough time to grow and influence the dynamics of Poynting-flux dominated jets. In the case of AGN jets, the flow becomes kinetic flux dominated at distances larger than ~1000 r_g because of the rapid dissipation of Poynting flux. When applied to GRB outflows, the model predicts more gradual Poynting dissipation and moderately magnetized flow at distances of ~10^{16} cm where the deceleration of the ejecta due to its interaction with the external medium is expected. The energy released by the instability can power the compact ``blazar zone'' emission and the prompt emission of GRB outflows with high radiative efficiencies.

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Dimitrios Giannios, Henk C. Spruit. 2006-01-23. The role of kink instability in Poynting-flux dominated jets. https://doi.org/10.1051/0004-6361%3A20054107

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