A new method for extracting x-ray absorption fine structure and the atomic background from an x-ray absorption spectrum

A new technique for separating x-ray absorption fine structure (XAFS) and the atomic background in an x-ray absorption spectrum is presented. XAFS oscillations are reliably extracted from the Fourier transform of the nth derivative of the experiment data, without making the usual smooth-background approximation. The atomic background is obtained by the subtraction of the XAFS from the experimental data. Multielectron excitations and atomic XAFS (AXAFS) have been observed in the atomic background. This provides a useful tool for the investigation of multielectron excitations and AXAFS in condensed matter.