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Polarization phenomena in the reaction NN to NNpi near threshold

C. Hanhart·J. Haidenbauer·O. Krehl·J. Speth
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Abstract

First calculations for spin-dependent observables of the reactions $pp \to ppπ^0$, $pp \to pnπ^+$ and $pp \to dπ^+$ near threshold are presented, employing the Jülich model for pion production. The influence of resonant (via the excitation of the $Δ(1232)$) and non-resonant p-wave pion production mechanisms on these observables is examined. For the reactions $pp \to pnπ^+$ and $pp \to dπ^+$ nice agreement of our predictions with the presently available data on spin correlation coefficents is observed whereas for $pp \to ppπ^0$ the description of the data is less satisfying.

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C. Hanhart, J. Haidenbauer, O. Krehl, J. Speth. 2000-02-09. Polarization phenomena in the reaction NN to NNpi near threshold. https://doi.org/10.1103/physrevc.61.064008

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