Plasmon Gains as a Monitor of Incomplete Relaxation, Interference Effects, and the Transition from Sudden to Adiabatic Limits in Electron Spectroscopies

This Letter reports on the KLL Auger spectra of Na and Mg excited with different x-ray sources. Intrinsic plasmon creation in x-ray photoemission leads to plasmongain satellites in the Auger process. With low-energy x rays the probability of intrinsic plasmon creation in x-ray photoemission and hence the plasmon-gain probability is reduced. With high-energy x rays the plasmon-gain intensities agree with predictions of a new formalism of photoemission and Auger transitions as a single quantum mechanical process.