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A next-to-next-to-leading order pp -> ppπ^0 transition operator in chiral perturbation theory

V. Dmitrašinović·K. Kubodera·F. Myhrer·T. Sato
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Abstract

We discuss the results of a systematic calculation of the next-to-next-to-leading order amplitude for the pp -> ppπ^0 S-wave production at the threshold in heavy-baryon chiral perturbation theory. We find six new diagrams, two of which can be viewed as vertex corrections, of 15 - 20 %, to the pion-exchange graph, whereas the rest are much larger, one exceeding 900 %. We discuss the reasons for this enhancement, as well as the steps necessary to be taken before the final comparison with experiment.

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V. Dmitrašinović, K. Kubodera, F. Myhrer, T. Sato. 1999-10-20. A next-to-next-to-leading order pp -> ppπ^0 transition operator in chiral perturbation theory. https://doi.org/10.1016/s0375-9474(99)00632-6

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