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arXiv · hep-ph/9612473

Cross-Symmetric Expansion of $ππ$ Amplitude Near Threshold

A. A. Bolokhov·T. A. Bolokhov·I. S. Manida·M. V. Polyakov·S. G. Sherman
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Abstract

The near-threshold expansion of the $ππ$ amplitude is developed using the crossing-covariant independent variables. The independent threshold parameters entering the real part of the amplitude in an explicitly Lorentz-invariant way are free from restrictions of isotopic and crossing symmetries. Parameters of the expansion of the imaginary part are recovered by the perturbative unitarity relations.

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A. A. Bolokhov, T. A. Bolokhov, I. S. Manida, M. V. Polyakov, S. G. Sherman. 1996-12-27. Cross-Symmetric Expansion of $ππ$ Amplitude Near Threshold. https://arxiv.org/abs/hep-ph/9612473

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