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Perturbative framework for the study of the properties of the pi(+)pi(-) atom

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

The perturbative framework is developed for the calculation of the pi(+)pi(-) atom characteristics (energy level shift and lifetime) on the basis of the field-theoretical Bethe-Salpeter approach. A closed expression for the first-order correction to the pi(+)pi(-) atom lifetime has been obtained.

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V. E. Lyubovitskij, E. Z. Lipartia, A. G. Rusetsky. 1997-06-04. Perturbative framework for the study of the properties of the pi(+)pi(-) atom. https://arxiv.org/abs/hep-ph/9706244

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