A modified magnetic bottle electron spectrometer for the detection of multiply charged ions in coincidence with all correlated electrons: decay pathways to Xe3+ above xenon-4d ionization threshold.

Single-photon multiple photoionization results from electron correlations that make this process possible beyond the independent electron approximation. To study this phenomenon experimentally, the detection in coincidence of all emitted electrons is the most direct approach. It provides the relative contribution of all possible multiple ionization processes, the energy distribution between electrons that can reveal simultaneous or sequential mechanisms, and, if possible, the angular correlations between electrons. In the present work, we present a new magnet design of our magnetic bottle electron spectrometer that allows the detection of multiply charged Xen+ ions in coincidence with n electrons. This new coincidence detection allows more efficient extraction of minor channels that are otherwise masked by random coincidences. The proof of principle is provided for xenon triple ionization.

Photoelectron Spectroscopy of Ions: Study of the Auger Decay of the 4d→nf (n=4,5) Resonances in Xe

We have studied, for the first time by electron spectroscopy, the Auger decay of the 4d→nf (n=4,5) resonances in Xe^{5+} ion. By detecting in coincidence the Auger electrons with the resulting Xe^{6+} ions, we unravel the contribution of the different final ionic states to the total cross section measured by ion spectroscopy. A strong intensity of 5s5p satellite lines has been observed, up to 4 times stronger than the 5s^{2} main lines. This unexpected behavior is confirmed by multiconfiguration Dirac-Fock calculations. This technique provides the most stringent test for theoretical models and allows us to disentangle the contribution of ions in the ground and metastable states in the target beam.

Angle-resolved photoelectron spectrometry studies of the autoionization of the 2s(2)2p 2P triply excited state of atomic lithium: experimental results and R-matrix calculations

We have measured the angle-resolved energy dependence of the electrons emitted over the energy range of the triply excited 2s(2)2p 2P lithium resonance using synchrotron radiation. We have also calculated the behavior of the angular distribution parameter beta using the R-matrix approximation. Experimental and theoretical results are in good agreement and show deep minima in the 1s2p (1, 3)P ionic channels. The energy at which the minima occur does not coincide with the resonance energy, but is shifted towards higher energy.

Dynamically and quasiforbidden transitions in photoionization of open-shell atoms: a combined experimental and theoretical study.

Completely fine-structure-resolved photoelectron spectra produced from sodium atoms selectively excited into the Na* 2p(6)3p (2)P(1/2) and (2)P(3/2) states were obtained using a third generation synchrotron source in conjunction with laser pumping and high-resolution spectrometry. The spectra show dramatically different behaviors. The strong variations observed in the regions of the Na+ 2p(5)3p (1,3)L(J) photolines and the Na+ 2p(5)4p (1,3)L(J) shakeup satellites are explained within a generalized geometrical model, accounting for the intermediate angular momentum coupling in the ionic states.