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 be easily 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 3 S1/2 →1S1/2 transition in neutral hydrogen as well as in various hydrogenlike ions.
U. D. Jentschura and A. S. Surzhykov, "Relativistic Calculation of the Two-Photon Decay Rate of Highly Excited Ionic States," Physical Review A - Atomic, Molecular, and Optical Physics, vol. 77, no. 4, pp. 042507-1-042507-5, American Physical Society (APS), Apr 2008.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevA.77.042507
Keywords and Phrases
Electrodynamics; Excited States; Quantum Theory; Resonance; Neutral Hydrogen; Quantum Electrodynamics; Two Photon Processes
International Standard Serial Number (ISSN)
Article - Journal
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