Double photoionization events provide a direct evaluation of electron correlation. The recent focus on few-electron targets continues to reveal the consequences of electron correlation for targets that possess several electrons. We consider the double photoionization of the 2p2 valence electrons of atomic carbon and focus on the first energetically accessible final-state symmetries that originate from coupling the active electrons in 3P configurations, which are doubly ionized by a single photon. Comparison of this process in carbon with neon provides an analogous case for the resulting final-state symmetries within the framework where the ejected electrons are influenced by the remaining bound electrons in a frozen-core approximation. Choosing this symmetry allows for comparison with previous theoretical results for total and energy sharing cross-sections of carbon. Fully differential cross-sections for both carbon and neon are also compared.
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State-Selective Double Photoionization of Atomic Carbon and Neon
Double photoionization (DPI) allows for a sensitive and direct probe of electron correlation, which governs the structure of all matter. For atoms, much of the work in theory and experiment that informs our fullest understanding of this process has been conducted on helium, and efforts continue to explore many-electron targets with the same level of detail to understand the angular distributions of the ejected electrons in full dimensionality. Expanding on previous results, we consider here the double photoionization of two 2p valence electrons of atomic carbon and neon and explore the possible continuum states that are connected by dipole selection rules to the coupling of the outgoing electrons in 3P, 1D, and 1S initial states of the target atoms. Carbon and neon share these possible symmetries for the coupling of their valence electrons. Results are presented for the energy-sharing single differential cross section (SDCS) and triple differential cross section (TDCS), further elucidating the impact of the initial state symmetry in determining the angular distributions that are impacted by the correlation that drives the DPI process.
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- Award ID(s):
- 2309348
- PAR ID:
- 10621452
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Atoms
- Volume:
- 12
- Issue:
- 12
- ISSN:
- 2218-2004
- Page Range / eLocation ID:
- 70
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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