Regular Article

Auger-like correlations in the two-photon above threshold ionization of Ar^⋆

¹ Rostov State University of Transport Communications, 344038 Rostov-on-Don, Russia
² Institute of Physics, Southern Federal University, 344090 Rostov-on-Don, Russia
³ Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, 34132 Kassel, Germany

^a e-mail: bml58@mail.ru

Received: 9 November 2018
Received in final form: 8 February 2019
Published online: 14 May 2019

Abstract

The two-photon above-threshold 3p-ionization of argon for the photon energies exceeding the 3p-ionization threshold is studied using the correlation function technique. Generalized two-photon ionization cross sections were calculated taking into account many-electron correlations. The calculations demonstrate that the two-photon ionization of Ar at the 3p⁴ threshold is almost entirely a collective process. The decisive contribution in the above-threshold two-photon 3p-ionization at the exciting-photon energies corresponding to the 3p→εd giant resonance comes from the Auger-like many-electron correlations of ε′ dε″d − 3pεf type.