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arXiv · 0807.0651

Relativistic calculation of the two-photon decay rate of highly-excited ionic states

Ulrich D. Jentschura·Andrey Surzhykov
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Abstract

Based on quantum electrodynamics, we reexamine the two-photon decay of one-electron atoms. Special attention is paid to the calculation of the (two-photon) total decay rates which can be viewed as the imaginary part of the two-loop self-energy. We argue that our approach can easily be applied to the cases with a virtual state having an intermediate energy between the initial and the final state of the decay process leading, thus, to the resonance peaks in the two-photon energy distribution. In order to illustrate our approach, we obtain fully relativistic results, resolved into electric and magnetic multipole components, for the two-photon decay rates of the 3S_{1/2} -> 1S_{1/2} transition in neutral hydrogen as well as in various hydrogen-like ions.

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Ulrich D. Jentschura, Andrey Surzhykov. 2008-07-03. Relativistic calculation of the two-photon decay rate of highly-excited ionic states. https://doi.org/10.1103/physreva.77.042507

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