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First printed in 1934, this book gives a critical survey of the principles and limitations of methods for studying resonance radiation that is the re-emission of absorbed radiation without change of wavelength and of the theoretical interpretation of the phenomenon. At the time of first publication, physicists had come to the limit of the then existing techniques in the field and the book was more useful to astronomers who were interested in line shapes existing in the spectra of stars. In past years other fields and techniques have developed for which the information in this book is of interest. These fields are: (1) those having to do with the determination of spins, magnetic moments and hyperfine structure separations by the methods of 'optical pumping' and 'optical double resonance': (2) optical MASERS; and (3) nuclear resonance absorption of gamma rays.

An introduction to the physics of highly excited, easily perturbed or interacting atoms. Covers Rydberg states, quantum defect theory, atomic f-values, centrifugal barrier effects, autoionisation, inner shell and double excitation spectra, K-matrix theory, atoms in high laser fields, statistical methods, quantum chaos, and atomic effects in solids.

This book describes selected problems in contemporary spectroscopy in the context of quantum mechanics and statistical physics. It focuses on elementary radiative processes involving atomic particles (atoms, molecules, ions), which include radiative transitions between discrete atomic states, the photoionization of atoms, photorecombination of electrons and ions, bremsstrahlung, photodissociation of molecules, and photoattachment of electrons to atoms. In addition to these processes, the transport of resonant radiation in atomic gases and propagation of infrared radiation in molecular gases are also considered. The book subsequently addresses applied problems such as optical pumping, cooling of gases via laser resonance radiation, light-induced drift of gas atoms, photoresonant plasma, reflection of radio waves from the ionosphere, and detection of submillimeter radiation using Rydberg atoms. Lastly, topical examples in atmospheric and climate change science are presented, such as lightning channel glowing, emission of the solar photosphere, and the greenhouse phenomenon in the atmospheres of the Earth and Venus. Along with researchers, both graduate and undergraduate students in atomic, molecular and atmospheric physics will find this book a useful and timely guide.

Intended for advanced students of physics, chemistry and related disciplines, this text treats the quantum theory of atoms and ions within the framework of self-consistent fields. Data needed for the analysis of collisions and other atomic processes are also included.

Atomic and Electron Physics

A comprehensive textbook and reference for the study of the physics of ionized gases The intent of this book is to provide deep physical insight into the behavior of gases containing atoms and molecules from which one or more electrons have been ionized. The study of these so-called plasmas begins with an overview of plasmas as they are found in nature and created in the laboratory. This serves as a prelude to a comprehensive study of plasmas, beginning with low temperature and "ideal" plasmas and extending to radiation and particle transport phenomena, the response of plasmas to external fields, and an insightful treatment of plasma waves, plasma instabilities, nonlinear phenomena in plasmas, and the study of plasma interactions with surfaces. In all cases, the emphasis is on a clear and unified understanding of the basic physics that underlies all plasma phenomena. Thus, there are chapters on plasma behavior from the viewpoint of atomic and molecular physics, as well as on the macroscopic phenomena involved in physical kinetics of plasmas and the transport of radiation and of charged particles within plasmas. With this grounding in the fundamental physics of plasmas, the notoriously difficult subjects of nonlinear phenomena and of instabilities in plasmas are then treated with comprehensive clarity.

Radiation can be absorbed and re-emitted many times in atomic vapors before it reaches the boundaries of the container encasing the vapor. This effect is known as radiation trapping. It plays an important role practically everywhere atomic vapors occur, whether in spectroscopy, gas lasers, atomic line filters, the determination of atomic lifetimes, measurements of atomic interaction potentials, or electric discharge lamps. This book is the first to assemble all of the information necessary to handle practical problems related to radiation trapping, and it emphasizes both physical insights and mathematical methods. The introduction reviews resonance radiation and collision processes in atomic vapors. This is followed by detailed explanations of the physical effects and mathematical methods for various types of problems (e.g., with or without saturation, particle diffusion, reflecting cell walls). The last part of the book describes the applications of these methods to a variety of practical problems, such as cross-section measurements and the design of discharge lamps.