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arXiv · 0709.3828

Nonlinear growth of firehose and mirror fluctuations in turbulent galaxy-cluster plasmas

A. A. Schekochihin·S. C. Cowley·R. M. Kulsrud·M. S. Rosin·T. Heinemann
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Abstract

In turbulent high-beta astrophysical plasmas (exemplified by the galaxy cluster plasmas), pressure-anisotropy-driven firehose and mirror fluctuations grow nonlinearly to large amplitudes, dB/B ~ 1, on a timescale comparable to the turnover time of the turbulent motions. The principle of their nonlinear evolution is to generate secularly growing small-scale magnetic fluctuations that on average cancel the temporal change in the large-scale magnetic field responsible for the pressure anisotropies. The presence of small-scale magnetic fluctuations may dramatically affect the transport properties and, thereby, the large-scale dynamics of the high-beta astrophysical plasmas.

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A. A. Schekochihin, S. C. Cowley, R. M. Kulsrud, M. S. Rosin, T. Heinemann. 2008-02-29. Nonlinear growth of firehose and mirror fluctuations in turbulent galaxy-cluster plasmas. https://doi.org/10.1103/physrevlett.100.081301

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