The NATO . Advanced Research Insti tute on Nonequilibrium Processes in Partially Ionized Gases was held at Acquafredda di Maratea during 4-17 June 1989. The Institute considered the interconnections between scattering and transport theories and modeling of nonequilibrium systems generated by electrical discharges, emphasizing the importance of microscopic processes in affecting the bulk properties of plasmas. The book tries to reproduce these lines. In particular several contributions describe scattering cross sections involving electrons interacting with atoms and molecules in both ground and excited states (from theoretical and experimental point of view), of energy transfer processes as well as reactive ones involving excited molecules colliding with atoms and molecules as well as with metallic surfaces. Other contributions deal with the basis of transport theories (Boltzmann and Monte Carlo methods) for describing the bulk properties of non equilibrium plasmas as well as with the modeling of complicated systems emphasizing in particular the strong coupling between the Boltzmann equation and excited state kinetics. Finally the book contains several contributions describing applications in different fields such as Excimer Lasers, Negative Ion Production, RF Discharges, Plasma Chemistry, Atmospheric Processes and Physics of Lamps. The Organizing Committee gratefully acknowledges the generous financial support provided by the NATO Science Committee as well as by Azienda Autonoma di Soggiorno e Turismo of Maratea, by University of Bari, by C. N. R. (Centro di Studio per la Chimica dei Plasmi and Comitato per la Chimica), by ENEA, by Lawrence Livermore Laboratory and by US Army Research Office.

Transport phenomena in plasmas are the relatively slow processes of particle momentum and energy transport systems in a state of mechanical equilibrium. In contrast to neutral gases, these phenomena in plasmas are greatly influenced by self-consistent fields, in particular electric fields. These can produce particle and energy fluxes, in addition to those generated by the inhomogeneity of the plasma composition and temperature. As a result, the physical effects accompanying transport phenomena in plasmas are far more numerous and complicated than those in neutral gases, and the solution of corresponding problems is more difficult. The effects, however, are usually far more interesting and sometimes surprising. This book presents a systematic survey and analysis of the main mechanisms of transport phenomena in plasma and gives examples of gradually increasing complexity to illustrate these mechanisms and the relationships between them. The author pays special attention to the analysis of experimental measurements and considers the relevant processes analytically as well as qualitatively. The majority of problems dealt with in this book are of considerable practical interest, and the phenomena described often determine the main characteristics of processes and devices. Transport Phenomena in Partially Ionized Plasma will be of interest to researchers who need to know the properties of real, specific systems, as well as to engineers and advanced students in the physics of plasmas, semiconductors, various types of gas discharges and the ionosphere.

The growing number of scientific and technological applications of plasma physics in the field of Aerospace Engineering requires that graduate students and professionals understand their principles. This introductory book is the expanded version of class notes of lectures I taught for several years to students of Aerospace Engineering and Physics. It is intended as a reading guide, addressed to students and non-specialists to tackle later with more advanced texts. To make the subject more accessible the book does not follow the usual organization of standard textbooks in this field and is divided in two parts. The first introduces the basic kinetic theory (molecular collisions, mean free path, etc.) of neutral gases in equilibrium in connection to the undergraduate physics courses. The basic properties of ionized gases and plasmas (Debye length, plasma frequencies, etc.) are addressed in relation to their equilibrium states and the collisional processes at the microscopic level. The physical description of short and long-range (Coulomb) collisions and the more relevant collisions (elementary processes) between electrons' ions and neutral atoms or molecules are discussed. The second part introduces the physical description of plasmas as a statistical system of interacting particles introducing advanced concepts of kinetic theory, (non-equilibrium distribution functions, Boltzmann collision operator, etc). The fluid transport equations for plasmas of electron ions and neutral atoms and the hydrodynamic models of interest in space science and plasma technology are derived. The plasma production in the laboratory in the context of the physics of electric breakdown is also discussed. Finally, among the myriad of aerospace applications of plasma physics, the low pressure microwave electron multipactor breakdown and plasma thrusters for space propulsion are presented in two separate chapters.

TO THE SECOND EDITION In the nine years since this book was first written, rapid progress has been made scientifically in nuclear fusion, space physics, and nonlinear plasma theory. At the same time, the energy shortage on the one hand and the exploration of Jupiter and Saturn on the other have increased the national awareness of the important applications of plasma physics to energy production and to the understanding of our space environment. In magnetic confinement fusion, this period has seen the attainment 13 of a Lawson number nTE of 2 x 10 cm -3 sec in the Alcator tokamaks at MIT; neutral-beam heating of the PL T tokamak at Princeton to KTi = 6. 5 keV; increase of average ß to 3%-5% in tokamaks at Oak Ridge and General Atomic; and the stabilization of mirror-confined plasmas at Livermore, together with injection of ion current to near field-reversal conditions in the 2XIIß device. Invention of the tandem mirror has given magnetic confinement a new and exciting dimension. New ideas have emerged, such as the compact torus, surface-field devices, and the EßT mirror-torus hybrid, and some old ideas, such as the stellarator and the reversed-field pinch, have been revived. Radiofrequency heat ing has become a new star with its promise of dc current drive. Perhaps most importantly, great progress has been made in the understanding of the MHD behavior of toroidal plasmas: tearing modes, magnetic Vll Vlll islands, and disruptions.

The dynamical equations for each component of a partially ionized monatomic gas are presented in two forms. These formulations should be most useful in analyzing the effects of ionization in such nonequilibrium regions as plasma oscillation and boundary layers. Using a perturbed Maxwellian distribution to evaluate the collision integrals, the appropriate transfer equations for the multi-component gas have been given. These transfer equations simplify greatly when the gas is assumed to be very lightly ionized and are reduced to the equations of a single-fluidwith-conduction model. Secondly, the equations for a three-fluid model are derived. In this model the properties of each species are defined in terms of its own motion, and not in terms of the total mass motion as in the one-fluid model. This model provides a useful physical interpretation of Joule heating effects. (Author).

When a laser beam of sufficiently high intensity interacts with a weakly ionized gas, the nonuniform deposition of laser energy into the electron gas causes heating of the electrons, ions, and neutral gas. Eventually, the neutral gas will 'break-down' and become more highly ionized. This ionization can seriously limit the amount of laser energy that can damage a target. A multifluid model has been devised to describe the many physical processes that occur when the high power laser wave interacts with the partially ionized gas. A flexible computer program has been developed to numerically integrate the multifluid plasma transport equations coupled with Maxwell's equations. The computer program is sufficiently general so as to be capable of describing target vaporization, with diffusion and ionization of target material into an ambient gas. In this report, only the modification of an ambient gas by the laser radiation is studied.

Provides a comprehensive review and usable problem-solving techniques for aerospace engineering plasma applications.