Measurement of the spectral distribution of low energy electrons emitted as a result of NVV auger transitions in Ag (100)

Auger Photoelectron Coincidence Spectroscopy (APECS) was used to investigate the physics of the Low Energy Tail (LET) of the Auger spectrum of Ag (100) at the National Synchrotron Light Source, Brookhaven National Lab, New York. The incident photon energy was set at 180eV. The spectrum shows a peak due to the NVV Auger transition accompanied by a substantial low energy region. The APECS spectrum contains the contributions from electrons excited by the NVV Auger transition plus a background due to true coincidences between photoemitted valence band electrons that undergo inelastic scattering and transfer part of their energy with other valence electrons which exit the sample. A series of coincidence measurements were made with the fixed analyzer set at energies 150,160,171.5 and 175eV. These measurements were used to obtain an estimate of the background due to the inelastically scattered valance band electrons. The estimated background was then subtracted from the NVV APECS data to obtain the spectrum of electrons emitted solely as a result of the NVV Auger transitions, which contains implications for quantitative interpretation of the Auger spectrum.