1. Coupling of charged particles via Coulombic interactions: Numerical simulations and resultant kappa-like velocity space distribution functions
- Author
-
E. R. Christian and Brent M. Randol
- Subjects
Physics ,Coupling ,Range (particle radiation) ,Number density ,010504 meteorology & atmospheric sciences ,Lambda ,01 natural sciences ,Charged particle ,Geophysics ,Distribution function ,Thermal velocity ,Space and Planetary Science ,Coupling parameter ,0103 physical sciences ,Atomic physics ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
A parametric study is performed using the electrostatic simulations of Randol and Christian (2014) in which the number density, n, and initial thermal speed, theta, are varied. The range of parameters covers an extremely broad plasma regime, all the way from the very weak coupling of space plasmas to the very strong coupling of solid plasmas. The first result is that simulations at the same Lambda(sub D), where Lambda(sub D) is the plasma coupling parameter, but at different combinations of n and theta, behave exactly the same. As a function of Lambda(sub D), the form of p(v), the velocity distribution function of v, the magnitude of v, the velocity vector, is studied. For intermediate to high D, heating is observed in p(v) that obeys conservation of energy, and a suprathermal tail is formed, with a spectral index that depends on Lambda(sub D). For strong coupling (Lambda(sub D) much > 1), the form of the tail is v5, consistent with the findings of Randol and Christian (2014). For weak coupling (Lambda(sub D much
- Published
- 2016