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Pionium in the elementary particle decays

Z. K. Silagadze
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Abstract

Some atomic decays of elementary particles with pionium ($π^+π^-$-dimesoatom) in the final state are considered. Only for K-meson atomic decays are the corresponding branching ratios big enough to make their experimental study realistic. The $O(α)$ order corrections to the lifetime of pionium are also calculated.

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Z. K. Silagadze. 1994-11-24. Pionium in the elementary particle decays. https://arxiv.org/abs/hep-ph/9411382

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