Photoacoustic X-ray absorption fine-structure spectroscopy of the Ni K-edge.

The X-ray absorption in a 5 μm thick Ni foil for energies from 8.2 keV to 8.8 keV was measured by the photoacoustic method using a gas-microphone-cell. Results are presented for both photoacoustic amplitude and phase as a function of incident photon energy. The absorption fine structure above the Ni K-edge is clearly resolved. The data are compared with a simple theory for the signal generation, and discrepancies are explained by discussing the various energy dissipation channels following the X-ray absorption. [ABSTRACT FROM AUTHOR]