I. Introduction
The ability of X-ray based techniques to separate magnetic contributions from different elements in a sample (element-specificity) has proven to be very valuable in studies of complex magnetic materials. In the case of X-ray magnetic circular dichroism (XMCD), this separation is achieved by tuning the x-ray energy to element-specific electron excitations whose response to circularly polarized (CP) X-rays of opposite helicities can be used to extract magnetic information from the excited element only [1], [2].