This book provides an introduction to the physics of emission, absorption and interaction of light in astrophysics and in laboratory plasmas. Such study necessarily requires a wide range of modern physics understanding involving electricity and magnetism, relativity, atomic structure, quantum mechanics, particle collision theory, statistical physics and more. Indeed, the analysis of light emission and collisional processes relevant to plasmas has provided much of the experimental evidence for quantum mechanics. The atomic and radiation physics of plasmas is, consequently, an ideal subject for study as an extension to material taught to physics undergraduates. The book combines undergraduate-level studies of the quantum mechanics of ions/atoms with the atomic and radiation physics of plasmas, though non-quantum models are used extensively. Atomic and radiation physics is presented at a level aimed at undergraduates in their final two years through to graduate students and researchers. Material needed for research in plasma physics and astrophysics is derived.

Plasma physicists working in a range of areas from astrophysics, magnetic fusion and inertial fusion to low-temperature plasmas of technological significance utilise atomic and radiation physics to interpret measurements. Plasma physics is a growing research area with the construction of the ITER tokamak, new laser-plasma facilities and the development of new methods of creating plasma, such as with free-electron lasers. Atomic and radiation physics is also an essential component in the theoretical development and simulation of astrophysical and laboratory plasmas. One aim of this book is to emphasise the overlap of atomic/radiation physics between astrophysical and laboratory plasmas, an imbrication exploited in the expanding field of laboratory astrophysics where physical scenarios relevant to astrophysics are simulated in the laboratory.

Due to the range of understanding required for research in the atomic and radiation physics of plasmas, the underlying physics is often not developed in research publications in astrophysics and plasma spectroscopy. An aim of this book has been to start with the knowledge obtained by physics graduates before they begin to specialise and to develop formulae and explain techniques used in plasma spectroscopy. The areas of plasma research utilising aspects of atomic and radiation physics are briefly introduced before spectroscopic applications are covered, but this book concentrates on the underlying atomic and radiation physics.