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arXiv · 1005.0549

Auger decay of 1σg and 1σu hole states of N2 molecule: disentangling decay routes from coincidence measurements

S. K. Semenov·M. S. Schöffler·J. Titze·N. Petridis·T. Jahnke·K. Cole·L. Ph. H. Schmidt·A. Czasch·D. Akoury·O. Jagutzki·J. B. Williams·T. Osipov·S. Lee·M. H. Prior·A. Belkacem·A. L. Landers·H. Schmidt-Böcking·Th. Weber·N. A. Cherepkov·R. Dörner
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Abstract

Results of the most sophisticated measurements in coincidence of the angular resolved K-shell photo- and Auger-electrons, and of two atomic ions produced by dissociation of N2 molecule, are analyzed. Detection of photoelectrons at certain angles allows separating the Auger decay processes of the 1σg and 1σu core hole states. The Auger electron angular distributions for each of these hole states are measured as a function of the kinetic energy release of two atomic ions and are compared with the corresponding theoretical angular distributions. From that comparison one can disentangle the contributions of different repulsive doubly charged molecular ion states to the Auger decay. Different kinetic energy release values are directly related to the different internuclear distances. In this way one can trace experimentally the behavior of the potential energy curves of dicationic final states inside the Frank-Condon region. Presentation of the Auger electron angular distributions as a function of kinetic energy release of two atomic ions opens a new dimension in the study of Auger decay.

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S. K. Semenov, M. S. Schöffler, J. Titze, N. Petridis, T. Jahnke, K. Cole, L. Ph. H. Schmidt, A. Czasch, D. Akoury, O. Jagutzki, J. B. Williams, T. Osipov, S. Lee, M. H. Prior, A. Belkacem, A. L. Landers, H. Schmidt-Böcking, Th. Weber, N. A. Cherepkov, R. Dörner. 2010-05-04. Auger decay of 1σg and 1σu hole states of N2 molecule: disentangling decay routes from coincidence measurements. https://doi.org/10.1103/physreva.81.043426

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