Molecular Processes In Plasmas

A variety of plasmas include molecules rather than only ions or atoms. Examples are ionospheres of the Earth and other planets, stellar atmospheres, gaseous discharges for use in various devices and processes, and fusion plasmas in the edge region. This book describes the role of molecules in those plasmas by showing elementary collision processes involving those molecules.

This well-illustrated resource provides vital cross-section information for the atomic and molecular collision processes taking place in the boundary region of magnetically confined fusion plasmas and in other laboratory and astrophysical low-temperature plasmas. The expertly assessed information in this noteworthy volume includes the most recent experimental and theoretical results presented in a convenient format. Coverage includes the processes of electron-impact excitation and ionization of plasma edge atoms, electron-ion recombination, dissociative collision processes involving electrons and much more.

Atomic and molecular processes play an important role in laboratory and astrophysical plasmas for a wide range of conditions, and determine, in part, their electrical, transport, thermal, and radiation properties. The study of these and other plasma properties requires a knowledge of the cross sections, reaction rate coefficients, and inelastic energy transfers for a variety of collisional reactions. In this review, we provide quantitative information about the most important collision processes occurring in hy drogen, helium, and hydrogen-helium plasmas in the temperature range from 0. 1 eV to 20 keY. The material presented here is based on published atomic and molecular collision data, theoretical calculations, and appro priate extrapolation and interpolation procedures. This review gives the properties of each reaction, graphs of the cross sections and reaction rate coeffiCients, and the coefficients of analytical fits for these quantities. We present this information in a form that will enable researchers who are not experts in atomic physics to use the data easily. The authors thank their colleagues at the Princeton Plasma Physics Laboratory and in the atomic physics community who have made many useful suggestions for the selection and presentation o. f t. he material. We gratefully acknowledge the excellent technical assistance of Elizabeth Carey for the typing, and Bernie Giehl for the drafting. This work was supported in part by the U. S. Department of Energy Contract No. DE-AC02-76-CHO-3073. Princeton, USA R. K. Janev W. D. Langer September, 1987 K. Evans, Jr. , D. E.

Atomic processes in plasmas and gases encompass broad areas in theoretical, experimental, atomic and molecular physics. One example is atomic processes that are involved in the study of various plasmas over a wide range of electron densities and temperatures. The topics in this area covered in the present book include magnetic fusion plasmas, laser-produced plasmas, as well as plasma spectroscopy for all of the above applications. Another example is atomic and molecular processes in neutral gases. Rydberg polar molecules in particular are covered in this book.

This conference brought together people working in various areas of atomic and molecular physics on one hand and the plasma physics on the other. Atomic and molecular processes, such as energy levels, radiative rates and scattering cross sections, play an important role in diagnostics and modeling of a variety of plasmas, such as astrophysical, fusion, lasing, and solar. Atomic processes also help in understanding the dynamics and compositions of these plasmas and hence the conference was useful for those who generate, assess, and apply the atomic and molecular data in understanding plasmas.

Atomic and Molecular Processes focuses on radiative and collisional processes involving atoms or molecules, including photoionization, elastic and inelastic scattering of electrons, energy loss by slow electrons, excitation, ionization, detachment, charge transfer, elastic scattering, and chemical reactions. The selection first offers information on forbidden and allowed transitions, including forbidden transitions in diatomic molecular spectra; forbidden transitions in crystals; calculations of atomic line strengths; and measurements of atomic transition probabilities. The book also ponders on photoionization processes, photodetachment, and high temperature shock waves. The manuscript elaborates on electronic and ionic recombination, elastic scattering of electrons, and the motions of slow electrons in gases. The book also evaluates the theory of excitation and ionization by electron impact; measurement of collisional excitation and ionization cross sections; and spectral line broadening in plasmas. The selection is a dependable reference for readers interested in atomic and molecular processes.

Contains papers based on 30 talks presented at the Tenth American Physical Society Topical Conference on Atomic Processes in Plasmas, held in San Francisco in January 1996. The volume begins with a section on atomic physics in tokamak plasmas, followed by sections covering atomic physics in astrophy