Evolution of large-scale magnetosonic structures to trains of solitary waves

Abstract

[1] Large-amplitude magnetic pulsations on ion inertial length scales are often observed in space plasmas, but their theoretical explanation is still controversial. We discuss a possible mechanism, different from ideas based on the classical plasma instabilities, for the generation of these pulsations. It is demonstrated that a competition between dispersion and wave steepening processes can lead to the transformation of a large-scale magnetosonic structure into trains of solitons. This kind of longitudinal filamentation is possible for both slow and fast magnetosonic perturbations. Results of numerical simulations are compared with Cluster spacecraft measurements and show that the steepening filamentation mechanism can explain the emergence of a certain class of solitary waves observed in space plasmas.

Pulsating aurora beyond the ultra‐low‐frequency range

“…The sinusoidal wave forms as expected from flickering aurora are very different from the appearance of 20–30 ms pulses. We may need to introduce a different type of transient excitation of dispersive and nonlinear properties of Alfven waves, such as Alfvenons [ Stasiewicz and Ekeberg , 2008] and trains of solitons [ Strumik et al , 2011] to realize rapidly changing spatial extent near the edge of pulsation to support the near‐Earth hypothesis.…”

Multidimensional Hall magnetohydrodynamics with isotropic or anisotropic thermal pressure: Numerical scheme and its validation using solitary waves

“…HMHD-related phenomena are studied as an important element of fast magnetic reconnection [2,3,4]. The HMHD physics includes also processes of formation of solitary waves [5,6,7,8]. The Hall term is also important for modeling small-scale fluctuations in plasma turbulence [9,10].…”