Effects of chemical potentials on isothermal ion-acoustic solitary waves and their three-dimensional instability in a magnetized ultra-relativistic degenerate multicomponent plasma

Abstract

The three-dimensional instability of isothermal ion-acoustic (IIA) solitary waves is examined in a magnetized ultra-relativistic degenerate multicomponent plasma, comprising nondegenerate inertial warm ions and ultra-relativistic degenerate inertialess electrons as well as positrons, by applying a small-k (long wavelength) expansion method. The nonlinear dynamics of IIA solitary waves in such a plasma model are governed by the nonlinear Zakharov–Kuznetsov equation. To perform the analysis, the instability criterion and the growth rate of the instability of IIA solitary waves have been obtained. A careful investigation shows that the amplitude, the width, the growth rate, and the instability of IIA solitary waves increase with the increasing chemical potential of electrons. The stable region of IIA solitary waves increases with the increasing fermion population and the angle between the directions of propagation and the uniform magnetic field. The present study may be helpful for elucidating the physical nature of nonlinear waves in compact objects such as white dwarfs and neutron stars where the concentration of degenerate ultra-relativistic electrons and positrons and their chemical potentials play a crucial role.

Overtaking collisions of oblique isothermal ion‐acoustic multisolitons in ultra‐relativistic degenerate dense magnetoplasmas

“…Let us assume a three-dimensional magnetized ultra-relativistic degenerate astrophysical plasma system, which may exist in compact astrophysical objects, containing non-degenerate inertial warm ions and ultra-relativistic degenerate inertialess electrons, as well as positrons, in the presence of an external uniform magnetic field ⃗ B = B 0êz , whereê z is the unit vector along the z-axis. [40]…”

“…The number density for ultra-relativistic degenerate inertialess electrons and positrons are given by [15,19,40]:…”

“…In our model, we consider N = 3, which leads to  = 5∕3, and p 0 (= n (0) i k B T i ) is the ion pressure at equilibrium. [40]…”

“…Obviously, from Equation (40), we are dealing with three single OIIASs, each of them moving in the same direction. Moreover, k 1 , k 2 , and k 2 are the wavenumbers, which define the amplitude and polarity of the two and the three OIIASs in Equations (38) and (40), respectively, and in the linear dispersion relation.…”

Numerical simulations and bifurcation analysis of monotonic and oscillatory magnetosonic shock waves in a spin 1/2 degenerate quantum plasma

“…Consequently, the study of a QMP has gained much interest in research because of its potential applications in both astrophysical plasma (e.g. atmospheres of neutron stars or interiors of massive white dwarfs [10,11]) and laboratory ones (e.g. in nanoscale electromechanical systems [12][13][14] in laser interactions with atomic systems [15,16] and in dense laser plasmas [17]).…”