NPG Nonlinear Processes in Geophysics NPG Nonlin. Processes Geophys. 1607-7946 Copernicus Publications Göttingen, Germany 10.5194/npg-14-373-2007 Magnetic holes in plasmas close to the mirror instability Borgogno D. 1 Passot T. 1 Sulem P. L. 1 CNRS, Observatoire de la CÔte d'Azur, B.P. 4229, 06304 Nice Cedex 4, France 09 07 2007 14 4 373 383 Copyright: © 2007 D. Borgogno et al. 2007 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://npg.copernicus.org/articles/14/373/2007/npg-14-373-2007.html The full text article is available as a PDF file from https://npg.copernicus.org/articles/14/373/2007/npg-14-373-2007.pdf

Non-propagating magnetic hole solutions in anisotropic plasmas near the mirror instability threshold are investigated in numerical simulations of a fluid model that incorporates linear Landau damping and finite Larmor radius corrections calculated in the gyrokinetic approximation. This FLR-Landau fluid model reproduces the subcritical mirror bifurcation recently identified on the Vlasov-Maxwell system, both by theory and numerics. Stable magnetic hole solutions that display a polarization different from that of Hall-MHD solitons are indeed obtained slighlty below threshold, while magnetic patterns and spatio-temporal chaos emerge when the system is maintained in a mirror unstable regime.

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