Soft x-ray absorption magnetic circular dichroism study of ferromagnetic superconductor UGe2

X-ray absorption magnetic circular dichroism (XMCD) at the U N-4.5 edges was measured for the ferromagnetic superconductor UGe2 in the normal state. The orbital and spin magneic moments deduced from the sum rule analysis of the XMCD data indicate that the U atom in UGe2 is considered to be closer to the trivalent state rather than the tetravalent state. The temperature dependence of the XMCD signal does not show any significant anomaly at T-* similar to 30K, where the resistivity anomaly was observed at ambient pressure. The XMCD measurement at the U N-2,N-3 edge indicates that the U 6d electrons have negligibly small magnetic contributions.