Arbitrary Amplitude Oblique Electrostatic Solitary Waves in a Degenerate Cold Dusty Magnetoplasma

Abstract

Linear and nonlinear properties of obliquely propagating waves are studied in a degenerate dense cold magnetoplasma, comprising of Thomas–Fermi distributed electrons and ions as well as non-degenerate negatively charged dust particulates. By using the plane wave approximation, a linear dispersion relation for the dust-cyclotron (DC) and dust-acoustic (DA) waves is derived and analyzed numerically. For fully nonlinear waves, a Sagdeev pseudopotential theory is employed to derive an energy-balance equation and the soliton existence domain depending upon the dust concentration $(h)$ , obliqueness $(L_{z})$ , and Mach number $(M)$ . Numerical analysis reveals that the parameter $h$ enhances the domain for allowed Mach numbers, i.e., $M_{1} and therefore favoring the solitary excitations, where $M_{1}$ and $M_{2}$ are the lower and upper Mach numbers, respectively. In addition, the dust concentration significantly reduces the amplitude and the profile sharpness of the solitary pulses. Similarly, variations in the obliqueness parameter and the Mach numbers modify the wave characteristics. This paper is important for understanding the nonlinear properties of electrostatic excitations in degenerate dusty magnetoplasma, relevant to white dwarfs (WDs), namely $GD56,\,\,GD29-38,\,\,GD362$ , and $WD2115-560$ , being termed as the DUSTY DAZ WDs.