Disturbed bilateral relations: a guide for plasma characterization and global models

The study of the competition between equilibrium disturbing and equilibrium restoring mechanisms, reveals that the various equilibrium departures as found in different plasmas, have much in common. They can be seen as disturbances of bilateral relation; relations effectuated by forward and corresponding backward processes in the sense of detailed balancing. The deviations from the equilibrium form of the atomic state distribution function and the electron energy distribution function of atomic plasmas, which are the result of the escape of photons and electron-ion pairs, can be given in a simple equation in which the escape per balance time plays a leading role. The same idea can be used to construct a characterisation method that relates external control parameters to average values of internal plasma properties such as the electron density, electron temperature and the gas temperature. The global discharge model presented here includes gas heating and is applicable to atomic plasmas for which convection can be neglected.