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arXiv · hep-ph/9901394

Positronium S state spectrum: analytic results at O(m alpha^6)

Andrzej Czarnecki·Kirill Melnikov·Alexander Yelkhovsky
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Abstract

We present an analytic calculation of the O(m alpha^6) recoil and radiative recoil corrections to energy levels of positronium nS states and their hyperfine splitting. A complete analytic formula valid to O(m alpha^6) is given for the spectrum of S states. Technical aspects of the calculation are discussed in detail. Theoretical predictions are given for various energy intervals and compared with experimental results.

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Andrzej Czarnecki, Kirill Melnikov, Alexander Yelkhovsky. 1999-04-28. Positronium S state spectrum: analytic results at O(m alpha^6). https://doi.org/10.1103/physreva.59.4316

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