A Simple Method of the Hyperfine Field Direction Estimation from the Moessbauer Experiment

A simple method is proposed for the estimation of the average hyperfine field, i.e. the magnetization direction in the foil samples from the ⁵⁷Fe Moessbauer spectra measured at three different orientations. The intensity ratios in the Moessbauer spectra of the sample perpendicular to the gamma-ray propagation direction and tilted by 45° in the longitudinal and transversal planes yield both angle coordinates of the hyperfine field direction without supposing the direction vector normalization, i.e., avoiding the necessity of line intensities corrections. The method is demonstrated by showing the influence of heat and mechanical treatments on the magnetization direction in two amorphous alloys, Fe₈₀Cr₂Bi₁₄S₄ and Fe₄₀Ni₄₀B₂₀, the latter showing a pronounced stress annealing induced magnetic anisotropy.