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Chiral Perturbation Theory Calculations For S-wave $π^0$ production In pp Collision

E. Gedalin·A. Moalem. L. Razdolskaya
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Abstract

The total cross section for the pp --> pp $π^0$ reaction at energies close to threshold is calculated within the frame of a chiral perturbation theory. The tree and one loop diagrams up to chiral order D=2 contributions are taken into account. The $L^{(0)}$ isoscalar-scalar part of t-channel two-pion exchange loop diagrams enhances the production amplitude strongly. The calculated cross section scale and energy dependence are very close to data.

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E. Gedalin, A. Moalem. L. Razdolskaya. 1997-02-24. Chiral Perturbation Theory Calculations For S-wave $π^0$ production In pp Collision. https://arxiv.org/abs/hep-ph/9702406

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