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arXiv · hep-ph/9905539

Relativistic corrections to the Pionium Lifetime

Xinwei Kong·Finn Ravndal
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Abstract

Next to leading order contributions to the pionium lifetime are considered within non-relativistic effective field theory. A more precise determination of the coupling constants is then needed in order to be consistent with the relativistic pion-pion scattering amplitude which can be obtained from chiral perturbation theory. The relativistic correction is found to be 4.1% and corresponds simply to a more accurate value for the non-relativistic decay momentum.

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Xinwei Kong, Finn Ravndal. 1999-10-20. Relativistic corrections to the Pionium Lifetime. https://doi.org/10.1103/physrevd.61.077506

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