Generalized matching criterion for electrostatic ion solitary propagations in quasineutral magnetized plasmas

Abstract

Based on the magnetohydrodynamics (MHD) model, an exact arbitrary-amplitude general solution is presented for oblique propagation of solitary excitations in two-and three-component quasineutral magnetoplasmas, adopting the standard pseudopotential approach. It is revealed that the necessary matching criterion of existence of such oblique nonlinear propagations in two and three-fluid magnetoplasmas share global features. These features are examined for the cases of electron-ion and electron-positron-ion magnetoplasmas with diverse equations of state. This study also reveals that for electron-ion magnetoplasmas with plasma-frequencies larger than the cyclotron-frequency (B 0 < 0.137 √ n 0 ) a critical-angle of β cr = arccos B 0 /(0.137 √ n 0 ) exists, at which propagation of solitary excitation is not possible. Coriolis effect on allowed soliton matching condition in rotating magnetoplasmas is also considered as an extension to this work. Current investigation can have important implications for nonlinear wave dynamics in astrophysical as well as laboratory magnetoplasmas.

Oblique propagation of solitary electrostatic waves in magnetized plasmas with cold ions and nonthermal electrons

“…Oblique propagation of electrostatic waves and solitary structures in magnetized plasmas has, over the years, been investigated by several authors. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] The discussion has been carried out from different viewpoints: linear waves or weakly nonlinear solitons described by the reductive perturbation theory, or, less commonly, larger amplitude solitary structures treated through a Sagdeev pseudopotential approach. 15 It is the latter method that interests us here even though some authors also mention linear dispersion properties and/or cite weakly nonlinear results (but derived as a limiting case from the fully nonlinear approach).…”

“…Most of the papers studying oblique propagation of electrostatic modes in magnetized plasmas take the static field along one axis, thus leaving x and z as independent variables, in addition to time t. Later, a comoving coordinate is introduced to carry the analysis through, reducing the description to one effective coordinate. [1][2][3]5,7,[9][10][11][12][13][14] Another choice, one that we tend to prefer because it is simpler to work with, is that one axis is chosen along the direction of propagation and immediately in a comoving reference frame. 4,6,8 Working in the frame where the structure is stationary gives rise to straightforward integrations with respect to x, as t is eliminated from the very beginning.…”

“…As to the plasma models discussed, the fluid constituent is usually positive ions, which are treated as strictly cold 1,2,[4][5][6][7][8][9]12,13 or warm, 3,10,14 with various polytropic pressure-density relations, or else one cold electron component and an immobile background. 11 The hot electrons are inertialess and have different distributions: in the early days, Boltzmann, [1][2][3][4][5]7,8 more recently kappa, 9,11,13 Tsallis, 12 or Cairns.…”

Multi-dimensional instability of multi-ion acoustic solitary waves in a degenerate magnetized plasma

“…Therefore, the effect of the magnetic field has to be taken into account, especially for astrophysical observations (such as white dwarfs, neutron stars, magnetars, etc) where the high magnetic field plays an important role in the formation and stability of the existing waves [24]. Akbari-Moghanjoughi studied the head-on collision of electron-positron-ion magnetoplasmas [25][26][27][28][29] and quasineutral magnetoplasmas [30,31] with different species and distributions using the extended Poincaré-Lighthill-Kuo reductive perturbation method [25][26][27]29], the conventional extended multi-scales technique [28] and other methods for relativistic and non-relativistic cases. Very recently Shukla et al [32] investigated the nonlinear propagation of high-frequency coherent electromagnetic waves in a uniform quantum magnetoplasma composed of degenerate electron fluid and non-degenerate ion fluid.…”