Journal article

Publication year: 2018

Journal: Physical review A

Volume number: 97

Issue number: 2

ISSN: 2469-9926

eISSN: 2469-9934

DOI Link: https://doi.org/10.1103/PhysRevA.97.022709

Publisher: American Physical Society

Abstract: 
Fine details of the cross section for electron-impact ionization of metastable two-electron Li+(1s2s(3)S(1)) ions are scrutinized by both experiment and theory. Beyond direct knockoff ionization, indirect ionization mechanisms proceeding via formation of intermediate double K-vacancy (hollow) states either in a Li+ ion or in a neutral lithium atom and subsequent emission of one or two electrons, respectively, can contribute to the net production of Li2+ ions. The partial cross sections for such contributions are less than 4% of the total single-ionization cross section. The characteristic steps, resonances, and interference phenomena in the indirect ionization contribution are measured with an experimental energy spread of less than 0.9 eV and with a statistical relative uncertainty of the order of 1.7%, requiring a level of statistical uncertainty in the total single-ionization cross section of better than 0.05%. The measurements are accompanied by convergent-close-coupling calculations performed on a fine energy grid. Theory and experiment are in remarkable agreement concerning the fine details of the ionization cross section. Comparison with previous R-matrix results is less favorable.

Harvard Citation style: Müller, A., Borovik, A., Huber, K., Schippers, S., Fursa, D. and Bray, I. (2018) Indirect contributions to electron-impact ionization of Li+ (1⁢𝑠⁢2⁢𝑠⁢3𝑆1) ions: Role of intermediate double-𝐾-vacancy states, Physical review A, 97(2), Article 022709. https://doi.org/10.1103/PhysRevA.97.022709

APA Citation style: Müller, A., Borovik, A., Huber, K., Schippers, S., Fursa, D., & Bray, I. (2018). Indirect contributions to electron-impact ionization of Li+ (1⁢𝑠⁢2⁢𝑠⁢3𝑆1) ions: Role of intermediate double-𝐾-vacancy states. Physical review A. 97(2), Article 022709. https://doi.org/10.1103/PhysRevA.97.022709