The tungsten Auger transitions : 150–200 eV

The low-energy Auger spectrum of tungsten, induced by electron bombardment, has been studied. The second-derivative detection mode was employed to improve the resolution of fine structure. A comparison of N(E) spectra and yield curves with theoretical Auger rates and line energies showed that N_4,5N_6,7X processes dominate the spectrum, where X denotes N_6,7 or O_2,3. The core—core—valence (X = O_4,5) processes occur with low probability. The N₄N₅V transition appears to be energetically allowed in tungsten, and to occur at a sufficiently high rate to alter the initial N₅ : N₄ hole-states ratio for the above Coster—Kronig and super-Coster—Kronig processes. For primary excitation energies above 425 eV, there is also a small contribution (about 12% at maximum) from N₃N₅V processes, which occurs around 166 eV.