Effect of anisotropic pressure on electron acoustic oscillatory and monotonic shocks in superthermal magnetoplasma

摘要

Nonlinear oscillatory and monotonic electron acoustic shock waves in dissipative magnetorotating electron-positron-ion plasmas containing cold dynamical electrons, superthermal electrons, and positrons have been analyzed in the stationary background of massive positive ions. The Korteweg de-Vries-Burgers equation which describes the dynamics of the nonlinear shock structures is derived by using amplitude reductive perturbation technique. The quantitative analysis of impact of different physical parameters on the shock structures is presented here. The electron fluid viscosity plays a pivotal role for the transition of electron acoustic (EA) monotonic to oscillatory shocks and vice versa. It is remarkable that the shock structures are sensitive to the Coriolis force, obliqueness, electron temperature, and the positrons concentration. The present work may be employed to explore and to understand the formation of electron acoustic shock structures in the space and laboratory plasmas with superthermal electrons and positrons under magnetorotating effects, especially in auroral zone, Van Allen radiation belts, planetary magnetospheres, pulsars, black-hole magnetospheres, etc.