New types of electron beam generated electric discharge in dense gases - A 'fountain' and a 'thunderstorm'
1999, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. The paper presents qualitative ideas and modeling resultson dynamics ofplasmas generated in air and other gases by injecting beams of high-energy electrons. Two distinct regimes are found, differing in a way that the excess negative charge brought in by the ionizing electron beam is removed. In the first regime, called a fountain, the charge is removed by the back current of plasma electrons towards the injection foil. In the second, called a thunderstorm, a substantial cloud of negative charge accumulates, and the increased electric field near the cloud causes a streamer to strike between the cloud and a positive or grounded electrode, or between two different clouds created by two different beams. A quantitative analysis, including electron beam propagation, electrodynamics, charge particle kinetics, and a simplified heat balance, is performed in 1D approximation. Effects of non-one-dimensionality are discussed qualitatively.