Angular-Momentum and Spherical Tensor Operators

Abstract

We begin this book by reviewing the theory of angular-momentum and spherical tensor operators—emphasizing the analogy between them. The material which appears in the present chapter is treated more extensively in several monographs that are devoted entirely to angular-momentum theory [Rose 1957; Edmonds 1957; Fano and Racah 1959; Brink and Satchler 1968] and the reader is referred to these books for further details. We have tried, however, to include all the material we need for the following treatment of atomic systems. In the third chapter graphical methods of representing angular-momentum theory are introduced, and this technique is used in the fourth chapter to develop tensor-operator methods further. In later chapters angular-momentum graphs will be used frequently to evaluate the angular part of interaction matrix elements.