Microwave Discharges

Proceedings of a NATO ARW held in Vimeiro, Portugal, May 11-15, 1992

A comprehensive and unique account of the creation of artificially ionized layers in the middle and upper atmosphere, using powerful radio waves. Major physical mechanisms associated with the formation of the ionized region are studied in detail. The main part of the author's research is devoted to problems associated with the breakdown mechanisms for radio frequency discharges in air. A special chapter deals with breakdown in intersecting pulsed beams and the effects of recombination, diffusion and atmospheric winds on the stability of the structure. The kinetics of the plasma produced are also described. The authors examine possibilities of inducing changes in the chemical composition of the upper atmosphere by means of radio frequence heating, with promising effects on the concentration of constituents such as ozone. The feasibility of using this phenomenon for; ozone healing - in connection with the ozone holes in the polar regions is investigated. The text is a timely treatment of key topics in the field of ionospheric modification.

We have studied the products of Ar/N20 microwave discharges to determine their fitness as sources of atomic oxygen in discharge-flow reactors. For N20 feed rates below 10-20 micromol s−1, the discharge converts about 75 percent of the N20 to atomic oxygen, and in addition, produces small quantities of atomic nitrogen, generally less than 10 percent of the 0-atom product. At higher N20 feed rates the 0-atom production efficiency decreases, and some nitric oxide accompanies the 0-atoms out of the discharge.

This book resulted from the NATO Advanced Research Workshop on “Electron Kinetics and Applications of Glow Discharges,” held in St. Petersburg, Russia, on May 19-23, 1997. Glow discharges have found widespread applications in many technological processes from the manufacture of semiconductors, to recent developments in na- technology, to the traditional fields of gas lasers, and discharge lamps. Consequently, the interest in the physics of glow discharges has experienced yet another resurgence of interest. While the non-equilibrium character of glow discharges is widely accepted, the opinion still prevails that the main features can be captured by fluid models, and that kinetic treatments are only required for the understanding of subtle details. The erroneousness of this belief is demonstrated by the failure of fluid models to describe many basic features of glow discharges such as, for instance, electrode phenomena, striations, and collisionless heating effects. An adequate description of glow discharges thus has to be of kinetic nature.

A comprehensive and unique account of the creation of artificially ionized layers in the middle and upper atmosphere, using powerful radio waves. Major physical mechanisms associated with the formation of the ionized region are studied in detail. The main part of the author's research is devoted to problems associated with the breakdown mechanisms for radio frequency discharges in air. A special chapter deals with breakdown in intersecting pulsed beams and the effects of recombination, diffusion and atmospheric winds on the stability of the structure. The kinetics of the plasma produced are also described. The authors examine possibilities of inducing changes in the chemical composition of the upper atmosphere by means of radio frequence heating, with promising effects on the concentration of constituents such as ozone. The feasibility of using this phenomenon for; ozone healing - in connection with the ozone holes in the polar regions is investigated. The text is a timely treatment of key topics in the field of ionospheric modification.

An Advanced Study Institute on Radiative Processes in Discharge Plasmas was held at the Atholl Palace Hotel, Pitlochry, Perthshire, Scotland, June 23 through July 5, 1985. This publication is the Pro ceedings from that Institute. The Institute was attended by eighty-five Participants and Lecturers representing the United States, Canada, France, West Germany, Greece, The Netherlands, Portugal, Turkey, the United Kingdom, and Switzerland. A distinguished faculty of eighteen Lecturers was assembled and the topical program organized with the assistance of an Advisory Committee composed of: Dr. John Waymouth, USA; Dr. Timm Teich, Switzerland; Dr. Arthur Phelps, USA; Dr. Nicol Peacock, England; Professor Erich Kunhardt, USA; Dr. Anthony Hyder, USA; and Dr. Arthur Guenther, USA. The underlying theme and objective of the Institute was the enhance ment of scientific communication and exchange among academic, industrial, and national laboratory groups having a common concern for radiative processes in discharge plasmas. The program was organized into four major sessions sequentially treating: the fundamental science of visible and near-visible radiation in plasmas; the technology of discharge light sources; recent and novel methods for the generation of plasmas; and an update on advances in laser-based diagnostics. Each major session culmi nated in a panel discussion comprised of the Lecturers for that session.

This book includes original, peer-reviewed research papers from the 2023 4th International Symposium on Insulation and Discharge Computation for Power Equipment (IDCOMPU2023), held in Wuhan, China. The topics covered include but are not limited to: insulation, discharge computations, electric power equipment, and electrical materials. The papers share the latest findings in the field of insulation and discharge computations of electric power equipment, making the book a valuable asset for researchers, engineers, university students, etc.