Decay of a 2p inner-shell hole in an Ar(+) ion.

Direct measurements of the photoelectrons or Auger electrons associated with inner shell ionization of positively charged ions are extremely difficult and rarely realized. We propose an alternative method to simulate such measurements, based on core valence double photoionization of the neutral species. As an example, we obtain the spectroscopy, lifetimes, and Auger decays of the states arising from 2p inner shell ionisation of an Ar(+) ion. Observations compare well with theoretical predictions obtained within multiconfigurational Dirac-Fock formalism.

Ultrafast dynamics in postcollision interaction after multiple auger decays in argon 1s photoionization.

Argon 1s photoionization followed by multiple Auger decays is investigated both experimentally, by means of photoelectron-ion coincidences, and theoretically. A strong influence of the different Auger decays on the photoelectron spectra is observed through postcollision interaction which shifts the maximum of the energy distribution and distorts the spectral shape. A good agreement between the calculated and measured spectra for selected Ar(n+) ions (n=1-5) allows one to estimate the widths (lifetimes) of the intermediate states for each specific decay pathway.

Dynamics and post-collision interaction effects in two electron decay from the Xenon 4d hole.

Two Auger electrons, one very slow, one fast, have been detected in coincidence following near threshold 4d photoionization of the Xe atom. The distribution in the energy the two electrons share has been measured for the first time revealing the presence of post-collision interaction effects that provide unique information on the decay dynamics of the 4d hole. Analysis of the distorted line shapes indicates that the dominant process is decay of Xe+(4d(-1)) to Xe3+ through cascade emission of a zero kinetic energy Auger electron followed by a fast Auger electron. The widths of the intermediate Xe2+* states are estimated to be about 60 meV.