THEORETICAL AND MOLECULAR DYNAMICS STUDIES OF DENSE PLASMA MICROFIELD NONUNIFORMITY

摘要

We critically examine several theories of the electric microfield constrained average of the plasma microfield gradient artial derivε_i/partial deriv x_j>_ε where partial derivε_i/partial deriv x_j is a component of the plasma microfield spatial derivative and E is the magnitude of the microfield. This quantity is important in the treatment of ion quadrupole effects on Stark broadened line shapes. The constrained average itself is also of more general interest as a means of calculating other plasma quantities such as time derivatives of plasma microfields. We compare several theoretical models, both many-body and nearest-neighbor, with accurate molecular dynamics simulations. We show that one previously published many-body theory diverges for physical conditions of interest in plasmas.