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arXiv · hep-ph/9810497

Theory of the pi+ pi- atom

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

The relativistic perturbative approach based on the Bethe-Salpeter (BS) equation is developed for the study of the characteristics of the hadronic pi+ pi- atom. 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. The lifetime of the pi+ pi- atom in the two-loop order of the Chiral Perturbation Theory is predicted to be tau_1=(3.03\pm 0.10)\times 10^{-15}~s.

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M. A. Ivanov, V. E. Lyubovitskij, E. Z. Lipartia, A. G. Rusetsky. 1998-10-27. Theory of the pi+ pi- atom. https://arxiv.org/abs/hep-ph/9810497

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