THE TOTAL FLUORESCENCE YIELD FROM MAGNETIC-MATERIALS OBTAINED USING CIRCULARLY-POLARIZED X-RAYS

The circular dichroic signal in the total cross-section for resonance- enhanced electric dipole scattering is calculated by an analytic metho d. Applied to lanthanide ions, our results shows that the signal is pr oportional to the mean value of the orbital magnetic moment, to a good approximation. This finding is the same as that found, without approx imations, for the dichroic signal in the attenuation coefficient. Thus , the finding supports the use of the total fluorescence yield as a me thod of measuring the information known to be in the coefficient. An i on with a half-filled valence shell is shown to be an exceptional case . For f(7) the signal in the cross-section is proportional to the prod uct of the (spin) magnetic moment and the difference between the total decay widths for the M-4 and M-5 absorption lines. For all cases, we give the angular dependence of the total cross-section, with respect t o the direction of the primary radiation and the axis of quantization for the atomic states.