Non-equilibrium between electrons and field in a gas breakdown ionising wave. II. Structure of the leading edge

For pt.I see ibid., vol.14, p.649 (1981). The authors present here the results of the numerical solution to the macroscopic model of a gas discharge described in part I (preceding paper). This model considers the non-equilibrium between the electron energy and field in the electron shock leading the ionising wave in the discharge. It is possible to analyse the structure of this shock wave. It is found to be mainly composed of two unequal parts separated by the position of the electron pressure maximum. It is also possible through this model to calculate the principal physical quantities (density of charge carriers, field and electron temperature) in a non-equilibrium electron field discharge. The authors have elucidated the role of the different physical processes, or the roles of the terms of the model equation, in determining the difference between the static equilibrium temperature and the electron temperature. It is also shown that a steady-state shock solution to the nonlinear hydrodynamic model of the gas discharge can exist in the sense that an initially strong relative electron density gradient is maintained in the first zone of the electron shock, whereas the shock upstream can possibly produce a precursor effect due to the combined effects of thermal diffusion and overmultiplication of these hot electrons.