Fore-wake excitations from moving charged objects in a complex plasma

Abstract

A charged object moving at a supersonic speed in a plasma creates the familiar Mach cone structure in its wake but can also give rise to nonlinear wave excitations ahead of it. Using molecular dynamic simulations, we explore such fore-wake excitations in a strongly coupled dusty plasma and demonstrate the existence of precursor solitonic pulses and dispersive shock waves in that region. The excitation conditions as well as the propagation characteristics of such pulses are delineated as a function of the projectile velocity, the plasma density, the Coulomb coupling parameter, and the amount of charge on the projectile. Our simulation results provide a kinetic basis for earlier fluid model calculations and also give insights into the dynamical processes responsible for such excitations that can aid in future experimental and application oriented studies.