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arXiv · 2011.10872

Observation of an electric quadrupole transition in a negative ion: Experiment and Theory

C. W. Walter·S. E. Spielman·R. Ponce·N. D. Gibson·J. N. Yukich·C. Cheung·M. S. Safronova
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Abstract

The first direct experimental observation of an electric quadrupole ($\textit{E}$2) transition between bound states of an atomic negative ion has been made. The transition was observed in the negative ion of bismuth by resonant (1+1) photodetachment from Bi$^-$ $^3\textit{P}_2$ via excitation of the Bi$^-$ $^3\textit{P}_0$ fine structure state. The $\textit{E}$2 transition properties were independently calculated using a hybrid theoretical approach to account for the strong multi-level electron interactions and relativistic effects. The experimental and theoretical results are in excellent agreement, providing valuable new insights into this complex system and forbidden transitions in negative ions.

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C. W. Walter, S. E. Spielman, R. Ponce, N. D. Gibson, J. N. Yukich, C. Cheung, M. S. Safronova. 2020-11-21. Observation of an electric quadrupole transition in a negative ion: Experiment and Theory. https://doi.org/10.1103/physrevlett.126.083001

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