Nonlinear magnetosonic solitary and shock waves in strongly coupled quantum electron–positron–ion plasmas

Abstract

Two-dimensional nonlinear magnetosonic solitary and shock waves propagating perpendicular to the applied magnetic field are presented in quantum electron–positron–ion plasmas with strongly coupled classical ions and weakly coupled quantum electrons and positrons. The generalized viscoelastic hydrodynamic model is used for the ions and a quantum hydrodynamic model is introduced for the electrons and positrons. In the weakly nonlinear limit, a modified Kadomstev–Petviashvili (KP) equation with a damping term and a KP–Burgers equation have been derived in the kinetic regime and hydrodynamic regime, respectively. The analytical and numerical solutions of the modified KP and KP–Burgers equations are also presented and analysed with the typical parameters of a white dwarf star and pulsar magnetosphere, which show that the quantum plasma beta and the variation of positron number density have remarkable effects on the propagation of magnetosonic solitary and shock waves.