To disentangle strong resonant Auger decay lines after the ${\rm{O}}1{\rm{s}}\to 3{\sigma }_{u}^{* }$excitation in O2 molecules

Synopsis Atomic features may appear in the Auger electron spectra after an electron is excited from a core orbital to an antibonding orbital in molecules, as a result of complex competitions among electron and nuclear motions. Relatively weak atomic features were widely discussed in spectator Auger decay processes on top of O 1 s → 3 σ u * excitation in O 2 molecules. Thee strong Auger decay processes are heavily-overlapped in the electron spectrum and not discussed up to now. Here, using multi-particle coincidence setup, we separate these Auger decay processes for the first time.