Identification of the Magnetostatic Modes of Ferrimagnetic Resonant Spheres

A detailed comparison between the magnetostatic theory and experimental observation is given. Both the resonant field and the intensity of the magnetostatic modes are compared. The disagreement between observation of resonant fields and the static theory is about 50 gauss for an yttrium iron garnet sphere 1.3 mm in diameter. Inclusion of the first-order propagation corrections reduces this disagreement to less than two gauss for 29 of the 31 modes that were compared. This increased accuracy allows both a more positive identification and a more accurate determination of g- factors. A comparison of the static theory of intensities with observation has likewise been made. The observed intensities are close to the predicted intensities for some lines and from 4 to 100 times greater for others.