2.2   Mechanisms of a gas discharge

Figure 2.1 shows the V-I characteristic of a discharge in a gas-filled tube. In the non-self-sustain discharge, free electrons, generated by atmospheric radiation, lead to a low current. At a specific voltage-level, depending on the surrounding radiation, the current reaches a saturation-level, until the Townsend-mechanism is attained. The Townsend-mechanism is followed by a breakdown. If the current is not limited it will rise, until the arc starts to burn. At this point the voltage drops and the current is mostly limited by the feeding source and the impedance between the gap-electrodes and the source. The physical mechanisms are described in several papers (e.g. [Raizer1991], [NASSER1971]...).

Figure 2.1: Discharge Phases

This page is part of a Frameset: Electrodynamic Sculpture: A Thesis by Rafael Bräg.