Double photoionization of argon into the 3s3p 5 1 P- and3 P-states

Abstract

Abstract. Double photoionization of argon was studied by photon induced fluorescence spectroscopy (PIFS). Cross sections for the double photoionization into the 3s3p5 ~p, 3p states of Ar + + are presented for exciting photon energies between threshold and 120 eV. In the threshold range the energy dependencies of these cross sections were determined for the first time. Singlet and triplet states are populated with comparable probabilities at equal excess energies, in contrast to predictions of the extended Wannier theory. At h v = 100 eV the spin-orbit splitting of the 3s3p 5 3p state was resolved, and a cross section for the production of Ar + + 3s°3p 6 ~S 0 was determined for the first time.

Many-electron dynamics of atomic processes studied by photon-induced fluorescence spectroscopy

“…Fig. 5 displays the fluorescence spectrum of Ar resulting from single and double photoionization after excitation by photons of 100 eV (Möbus et al, 1994). The doublet at 91.9 nm and 93.2 nm following the 3s electron photoionization is clearly resolved.…”

“…In this way, PIFS is superior for investigations of ionization threshold phenomena to photoelectron spectrometries where photoelectrons of istering electrons e − for single or double ionization by photons of energy ω (adapted from (Schartner et al, 1990a)). Lines result from the 3s-electron and the 3s3p-electron single and double photoionization (adapted from Möbus et al (1994)).…”

“…Figure5: VUV fluorescence spectrum of Ar excited by 100 eV photons. Lines result from the 3s-electron and the 3s3p-electron single and double photoionization (adapted fromMöbus et al (1994)). …”