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O(alpha^3 ln alpha) corrections to muonium and positronium hyperfine splitting

Kirill Melnikov·Alexander Yelkhovsky
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Abstract

We compute O(alpha^3 ln alpha) relative corrections to the ground state hyperfine splitting of a QED two body bound state with different masses of constituents. The general result is then applied to muonium and positronium. In particular, a new value of the muon to electron mass ratio is derived from the muonium ground state hyperfine splitting.

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Kirill Melnikov, Alexander Yelkhovsky. 2000-10-18. O(alpha^3 ln alpha) corrections to muonium and positronium hyperfine splitting. https://doi.org/10.1103/physrevlett.86.1498

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