Modeling the plasma near-wakes

Abstract

An ambient unmagnetized plasma is considered in which a flat-based projectile of radius R and zero surface potential moves along its axis of symmetry at a constant mesothermal speed. The plasma cavity-filling process is likened to the transient flow associated with a radially imploding cylindrical shock seen immediately after the rupture of a cylindrical diaphragm of radius R. A modeling scheme is presented assuming that electron temperature remains constant and is much higher than the ion temperature in plasma and that ions move in a self-consistent electric field with which the electrons are already in Boltzmann equilibrium. A figure illustrates the ion density distributions at consecutive times after the start of implosion and the existence of an ion wavefront as a result of charge separation is clearly seen.