Abstract
An experimental investigation has been made of the size and width of the sharp maxima in the thermal conductivity of Al2O3 containing Fe2+ ions that occur when two of the resonant scattering frequencies present are made equal-frequency crossings. The crossings are brought about or resolved by applying a magnetic field. Two crossings were studied and the temperature and angular dependence of the size and width of the maxima were found to be in reasonable agreement with a recent analysis.