Abstract
The electron-spin-resonance and transmission-resonance line shapes in a metal containing impurities with local moments are evaluated for arbitrary exchange, hyperfine interaction, and nuclear spin using the Bloch-like equations derived by Langreth, Cowan, and Wilkins. Classical skin-depth conditions are assumed and the drift current produced by the gradient in the magnetic field is included in the diffusion term. Computer evaluation and a physical interpretation of the results are given. The theory is compared with the experimental transmission-resonance data in Cu:Mn. It is shown that the anomalies in the data are due to hyperfine interaction and a breakdown of strong coupling at low temperatures.