http://arxiv.org/abs/2205.02259
Relativistic magnetized jets, such as those from AGN, GRBs and XRBs, are susceptible to current- and pressure-driven MHD instabilities that can lead to particle acceleration and non-thermal radiation. Here we investigate the development of these instabilities through 3D kinetic simulations of cylindrically symmetric equilibria involving toroidal magnetic fields with electron-positron pair plasma. Generalizing recent treatments by valves et al. (2018) and Davelaar et al. (2020), we~consider a~range of~initial structures in~which the~force due~to~toroidal magnetic field is~balanced by~a~combination of~forces due~to~axial magnetic field and~gas pressure. We~argue that the~particle energy limit identified by Alves et al. (2018) is~due to~the~finite duration of~the~fast magnetic dissipation phase. We~find a~rather minor role of~electric fields parallel to~the~local magnetic fields in~particle acceleration. In~all investigated cases a~kink mode arises in~the~central core region with a~growth timescale consistent with the~predictions of~linearized MHD models. In the~case of~a~gas-pressure-balanced (Z-pinch) profile, we identify a~weak local pinch mode well outside the~jet core.
We argue that pressure-driven modes are important for relativistic jets, in regions where sufficient gas pressure is produced by other dissipation mechanisms.
J. Ortuño-Macías, K. Nalewajko, D. Uzdensky, et. al.
Fri, 6 May 22
28/55
Comments: 22 pages, 20 figures, accepted for publication in ApJ
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