Missing Auger electron emission lines of metallic Sn and Auger-photoelectron coincidence spectroscopy (APECS)

► The M4,5-N2,3N2,3 Auger-electron spectroscopy (AES) spectrum of atomic Sn is calculated by an ab initio atomic diagramatic perturbation theory. ► The AES spectrum is entirely smeared out and in good agreement with experiment. ► It shows the complete breakdown of the quasi-particle picture of the two N2,3 holes by the N2,3N2,3-N4,5N4,5N4,5N4,5 and N2,3N2,3-N2,3N4,5N4,5 super Coster-Kronig (sCK) transitions. ► By measuring the M4,5 photoelectron spectroscopy (PES) spectrum in coincidence with the M4,5-N2,3N2,3 Auger decay one can detect the missing M4,5-N2,3N2,3 AES lines.