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Forbidden transitions in the helium atom

Grzegorz Lach·Krzysztof Pachucki
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Abstract

Nonrelativistically forbidden, single-photon transition rates between low lying states of the helium atom are rigorously derived within quantum electrodynamics theory. Equivalence of velocity and length gauges, including relativistic corrections is explicitly demonstrated. Numerical calculations of matrix elements are performed with the use of high precision variational wave functions and compared to former results.

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Grzegorz Lach, Krzysztof Pachucki. 2001-05-31. Forbidden transitions in the helium atom. https://doi.org/10.1103/physreva.64.042510

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