$χ$PT Calculations with two-pion Loops for S-wave $π^0$ Production in pp Collision

E. Gedalin; A. Moalem; L. Razdolskaya

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$χ$PT Calculations with two-pion Loops 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 $pp \to pp π^0$ reaction at energies close to threshold is calculated within the frame of a chiral perturbation theory, taking into account tree and one loop diagrams up to chiral order D=2. Two-pion loop contributions dominate $π^0$ production at threshold. The calculated cross section reproduces data, both scale and energy dependence, fairly well.

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E. Gedalin, A. Moalem, L. Razdolskaya. 1998-03-09. $χ$PT Calculations with two-pion Loops for S-wave $π^0$ Production in pp Collision. https://arxiv.org/abs/nucl-th/9803029

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