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arXiv · 1702.01030

Colliding Alfv\'enic wave packets in MHD, Hall and kinetic simulations

O. Pezzi·T. N. Parashar·S. Servidio·F. Valentini·C. L. Vasconez·Y. Yang·F. Malara·W. H. Matthaeus·P. Veltri
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Abstract

The analysis of the Parker-Moffatt problem, recently revisited in Pezzi et al. (2016), is here extended by including the Hall magnetohydrodynamics and two hybrid kinetic Vlasov-Maxwell numerical models. The presence of dispersive and kinetic features is studied in detail and a comparison between the two kinetic codes is also reported. Focus on the presence of non-Maxwellian signatures shows that - during the collision - regions characterized by strong temperature anisotropy are recovered and the proton distribution function displays a beam along the direction of the magnetic field, similar to some recent observations of the solar wind.

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O. Pezzi, T. N. Parashar, S. Servidio, F. Valentini, C. L. Vasconez, Y. Yang, F. Malara, W. H. Matthaeus, P. Veltri. 2017-02-03. Colliding Alfv\'enic wave packets in MHD, Hall and kinetic simulations. https://doi.org/10.1017/s0022377817000113

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