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$π$NN coupling and two-pion photoproduction on the nucleon

M. Hirata·N. Katagiri·T. Takaki
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Abstract

Effects of non-resonant photoproductions arising from two different $πNN$ couplings are investigated in the $γN\toππN$ reaction. We find that the pseudoscalar (PS) $πNN$ coupling is generally preferable to the pseudovector (PV) $πNN$ coupling and particularly the total cross sections are successfully described by the model with the PS $πNN$ coupling. In order to see the difference between the two couplings, we also show the results of invariant mass spectra and helicity-dependent cross sections in various isospin channels calculated with the PS and PV couplings.

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M. Hirata, N. Katagiri, T. Takaki. 2003-02-01. $π$NN coupling and two-pion photoproduction on the nucleon. https://doi.org/10.1103/physrevc.67.034601

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