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arXiv · hep-ph/9805356

(Pi+Pi-) Atom in Chiral Perturbation Theory

M. A. Ivanov·V. E. Lyubovitskij·E. Z. Lipartia·A. G. Rusetsky
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Abstract

Hadronic (Pi+Pi-) atom is studied in the relativistic perturbative approach based on the Bethe-Salpeter equation. The general expression for the atom lifetime is derived. Lowest-order corrections to the relativistic Deser-type formula for the atom lifetime are evaluated within the Chiral Perturbation Theory.

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M. A. Ivanov, V. E. Lyubovitskij, E. Z. Lipartia, A. G. Rusetsky. 1998-05-18. (Pi+Pi-) Atom in Chiral Perturbation Theory. https://doi.org/10.1103/physrevd.58.094024

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