Calculating Microfield Angular Velocity Distribution in Plasma through Using Molecular Dynamics Simulation

Abstract

Considering the importance of statistics related to microfields in the spectral line shapes in plasma, many researchers were interested in calculating statistical distributions related to microfields with different models and approximations. Analytical approaches and numerical simulation methods can be used to study the variations of the magnitude or the directions of the microfield. The aim of this work is the calculation of distributions of microfield angles and distributions of microfield angular velocities on ions in plasmas. The article briefly presents an overview of previous work and the molecular dynamics simulation (MDS) technique used in this work. We consider interaction between all ions of the plasma according to Debye potential, and we follow evolution of the positions and velocities of particles according to Verlet algorithm. The results present effects of temperature and ion densities on calculated distributions. We compare our results with those of an analytical model based on Holtsmark model at the temperature 105 K, the ionic density 2.1015 cm–3 and for Z = +2 and Z = +5. Another comparison is done with independent particles model (IPM) for ionic coupling parameter equal to 0.17. Our values of the most probable angular velocity are less than those of the analytical calculation; differences may be caused mainly by the choice of the interaction potential and interaction between all ions in the plasma.