Interference effects between 2p photoionization and resonant Auger decay channel at 2s-1np (n=4, 5) inner hell resonances in Ar

The electron spectrum of Ar has been studied in the binding energy region of the 2p213p21np states. These states are populated in direct 2p photoionization accompanied by the 3p!np shake-up transitions. In addition, at photon energies corresponding to the 2s->4p,5p excitations they gain intensity through the 2s21np->2p213p21np resonant Auger decay channels. The two channels can interfere, leading to changes in the intensities of the Ar 2p photoelectron satellites. Experimental results are compared with the results of one-step calculations.