A Particle In Cell Method For Modeling Small Angle Coulomb Collisions In Plasmas

Collisions between particles in a hot plasma can be ignored in many high-temperature plasma simulations. However, at lower temperatures, collisional effects play a significant role in determining the plasma's overall behavior. While fluid modeling can accurately capture collisional effects (with some limitations), proper definition of boundary conditions for fluid modeling depend on accurate assumptions about the kinetic (real) behavior of plasma near material surfaces, where the plasma sheath dominates the plasma behavior. This thesis project is an attempt to develop a tool to elucidate sheath and presheath plasma behavior in the presence of strong collisional effects. Using the Particle In Cell (PIC) method, a Coulomb collisional model is implemented to study near-surface plasma behavior. The information gleaned from this project could provide important refinement of boundary conditions for fluid codes, and more generally, insights into kinetic behavior of the collisional plasma sheath.

This book examines the latest research results from combined multi-component and multi-scale explorations. It provides theory, considers underlying numerical methods and presents brilliant computational experimentation. Engineering computations featured in this monograph further offer particular interest to many researchers, engineers and computational scientists working in frontier modeling and applications of multicomponent and multiscale problems. Professor Geiser gives specific attention to the aspects of decomposing and splitting delicate structures and controlling decomposition and the rationale behind many important applications of multi-component and multi-scale analysis. Multicomponent and Multiscale Systems: Theory, Methods and Applications in Engineering also considers the question of why iterative methods can be powerful and more appropriate for well-balanced multiscale and multicomponent coupled nonlinear problems. The book is ideal for engineers and scientists working in theoretical and applied areas.

Written by a team of pioneering scientists from around the world, Low Temperature Plasma Technology: Methods and Applications brings together recent technological advances and research in the rapidly growing field of low temperature plasmas. The book provides a comprehensive overview of related phenomena such as plasma bullets, plasma penetration into biofilms, discharge-mode transition of atmospheric pressure plasmas, and self-organization of microdischarges. It describes relevant technology and diagnostics, including nanosecond pulsed discharge, cavity ringdown spectroscopy, and laser-induced fluorescence measurement, and explores the increasing research on atmospheric pressure nonequilibrium plasma jets. The authors also discuss how low temperature plasmas are used in the synthesis of nanomaterials, environmental applications, the treatment of biomaterials, and plasma medicine. This book provides a balanced and thorough treatment of the core principles, novel technology and diagnostics, and state-of-the-art applications of low temperature plasmas. It is accessible to scientists and graduate students in low-pressure plasma physics, nanotechnology, plasma medicine, and materials science. The book is also suitable as an advanced reference for senior undergraduate students.

This thesis makes two important contributions to plasma physics. The first is the extension of the seminal theoretical works of Spitzer and Braginskii, which describe the basics of particle interactions in plasma, to relativistic systems. Relativistic plasmas have long been studied in high-energy astrophysics and are becoming increasingly attainable in the laboratory. The second is the design of a new class of photon–photon collider, which is the first capable of detecting the Breit–Wheeler process. Though it offers the simplest way for light to be converted into matter, the process has never been detected in the 80 years since its theoretical prediction. The experimental scheme proposed here exploits the radiation used in inertial confinement fusion experiments and could in principle be implemented in one of several current-generation facilities.

This book combines the experience and achievements in engineering practice of the China Academy of Space Technology, Xi’an, with a focus on the field of high-power multipactor over recent decades. It introduces the main concepts, theories, methods and latest technologies of multipactor simulation, at both the theoretical level and as a process of engineering, while providing a comprehensive introduction to the outstanding progress made in the research technology of multipactor numerical simulation in China. At the same time, a three-dimensional numerical simulation method of multipactor for typical high-power microwave components of spacecraft is introduced. This book is an essential volume for engineers in the field of high-power microwave technology. It can also be used as a reference for researchers in related fields, or as a teaching reference book for graduate students majoring in Astronautics at colleges and universities.