Ion Acoustic Shock Waves with Nonextensive Electron Distributions in a Five-Component Cometary Plasma

Abstract

This work analyzes ion-acoustic shock waves in the presence of an external noise or perturbation by deriving the Korteweg–de Vries–Burgers–Kuramoto (KdVBK) equation. Our plasma model is a five-component magnetized, temperature anisotropic, cometary plasma consisting of two components of electrons (of solar and cometary origin) described by nonextensive distribution functions, a drifting ion component (H₃O⁺) and a pair of oppositely charged oxygen ion components. We have studied the solution of the KdVBK equation in the vicinity of the “inner shock” that occurred at a cometocentric distance of roughly 4000 km for comet 1P/Halley. A drop in the shock amplitude is observed with an increase in the nonextensive parameter of the electrons and as the temperature of the cometary electrons rise. It is found that a shock wave oriented perpendicular to the direction of the magnetic field dissipates more quickly than one that is parallel. As the values of the parallel pressures of H₃O⁺, O⁺ and O⁻ ions increase, the shock amplitude reduces. The dissipation coefficient C is found to rise with increasing kinematic viscosities of ions. Additionally, the shock amplitude exhibits a direct correlation with the ambient magnetic field strength. Also, in general, the shock amplitudes are slightly greater when described by the KdVBK equation rather than the KdVB equation.