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arXiv · hep-ph/9904478

alpha^2 corrections to parapositronium decay

Andrzej Czarnecki·Kirill Melnikov·Alexander Yelkhovsky
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Abstract

Two-loop QED corrections to the decay rate of parapositronium (p-Ps) into two photons are presented. We find Gamma(p-Ps --> 2 photons) = 7989.64(2)/microsec. The non-logarithmic O(alpha^2) corrections turn out to be small, contrary to some earlier estimates. We speculate that the so-called ``orthopositronium lifetime puzzle'' will not likely be solved by large QED corrections.

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Andrzej Czarnecki, Kirill Melnikov, Alexander Yelkhovsky. 2000-07-17. alpha^2 corrections to parapositronium decay. https://doi.org/10.1103/physrevlett.83.1135

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