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arXiv · 0811.0306

Irrational constants in positronium decays

B. A. Kniehl·A. V. Kotikov·O. L. Veretin
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Abstract

We establish irrational constants, that contribute to the positronium lifetime at $O(α)$ and $O(α^2)$ order. In particular we show, that a new type of constants appear, which are not related to Euler--Zagier sums or multiple $ζ$ values.

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B. A. Kniehl, A. V. Kotikov, O. L. Veretin. 2008-11-03. Irrational constants in positronium decays. https://doi.org/10.1016/j.nuclphysbps.2008.09.075

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