Argon-photoion–Auger-electron coincidence measurements followingK-shell excitation by synchrotron radiation

Abstract

Argon photoion spectra have been obtained for the first time in coincidence with K-LL and K-LM Auger electrons, as a function of photon energy. The simplified charge distributions which result exhibit a much more pronounced photon-energy dependence than do the more complicated noncoincident spectra. In the near-AT-threshold region, Rydberg shakeoff of np levels, populated by resonant excitation of K electrons, occurs with significant probability, as do double-Auger processes and recapture of the K photoelectron through postcollision interaction.

Final charge state distribution in the production and decay of hollow Ar

“…The details of the FCSD of Argon ions with the initial 1 s hole is summarized in Table 1. Excellent agreement between the theoretical RACS result and the available experimental data [6][7][8] is obtained, as shown in Fig. 1.…”

“…Some discrepancy was found in the case of the 2p hole, where the method seems to overestimate the SKOF contribution. The model is also capable of predicting in detail the X-ray and Auger spectra produced in the cascade decay of the initial hole [8], as well as that resulting from the primary SKOF. The discrepancy in the FCSD found in the earlier study with the R A C model is shown to be due to the shake-off effect in the initial stage of the hole production.…”

Investigation of the cascades in atoms using the global characteristics of spectra

“…The charge state and photoion spectra were studied for Ne [3,49], Ar [4,11,12,[50][51][52][53], Kr [5,6,33,[53][54][55][56], Xe [6,9,16,34,35,46,[57][58][59][60], and for all of them [61][62][63]. Also such spectra were investigated for lanthanides [7-9, 15, 32, 64-66], Mg [50,67], Al, Si, S, Ca, Fe [50], Cu [18], Sr [68], Ba [69], Au [70], Re [71], and Ta [71].…”

The advanced light source — a new tool for research in atomic physics

“…A few examples are photon-ion interactions, in which either the ion beam after the collision 2], or electrons emitted are detected; these ions can be highly charged. Other examples are coincidence experiments [3], where low collection efficiencies require intense photonbeams;experiments withactinide targets, wherematerial iseither scarce orhighlyradioactive; and laser-excited targets [4]. Many otherapplications inatomicphysics have been considered [5].…”