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arXiv · 1605.00363

Isospin decomposition of $γN \to N^*$ transitions within a dynamical coupled-channels model

H. Kamano·S. X. Nakamura·T. -S. H. Lee·T. Sato
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Abstract

By extending the dynamical coupled-channels analysis performed in our previous work [Phys. Rev. C 88, 035209 (2013)] to include the available data of photoproduction of pi meson off the neutron, the transition amplitudes for the photo-excitation of the neutron to nucleon resonances, gamma n --> N*, at the resonance pole positions are determined. The combined fits to the data for both the proton- and neutron-target reactions also revise our results for the resonance pole positions and the gamma p --> N* transition amplitudes. Our results allow an isospin decomposition of the gamma N --> N* transition amplitudes for the isospin I=1/2 N* resonances, which is necessary for testing hadron structure models and gives crucial inputs for constructing models of neutrino-induced reactions in the nucleon resonance region.

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H. Kamano, S. X. Nakamura, T. -S. H. Lee, T. Sato. 2016-07-07. Isospin decomposition of $γN \to N^*$ transitions within a dynamical coupled-channels model. https://doi.org/10.1103/physrevc.94.015201

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