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arXiv · hep-ph/9807474

pi+pi- Atom in Chiral Theories

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

We review the existing theoretical approaches to the study of the observables of hadronic atoms. In the relativistic perturbative approach based on the Bethe-Salpeter equation and Chiral Perturbation Theory we derive the general expression for the pi+pi- atom lifetime. The lowest-order correction to the relativistic Deser-type formula for the atom width is predicted to be 6.1\pm 3.1 %.

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M. A. Ivanov, V. E. Lyubovitskij, E. Z. Lipartia, A. G. Rusetsky. 1998-07-23. pi+pi- Atom in Chiral Theories. https://arxiv.org/abs/hep-ph/9807474

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