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arXiv · hep-ph/9510307

Extraction of the Ratio of the N^*(1535) Electromagnetic Helicity Amplitudes from Eta Photoproduction off Neutrons and Protons

Nimai C. Mukhopadhyay·J. -F. Zhang·M. Benmerrouche
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Abstract

Using the recent precise measurements of eta photopro- duction in proton and deuteron targets, we extract the ratio of the helicity amplitudes A^n_1/2 / A^p_1/2, for the excitation of N^*(1535), in the effective Lagrangian approach, It is fairly model-independent, free from the final-state interaction effects, and negative as predicted by the quark models. We stress the importance of polarization observables in further elucidation of the N^*(1520) photoexcitation amplitudes.

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Nimai C. Mukhopadhyay, J. -F. Zhang, M. Benmerrouche. 1995-10-16. Extraction of the Ratio of the N^*(1535) Electromagnetic Helicity Amplitudes from Eta Photoproduction off Neutrons and Protons. https://doi.org/10.1016/0370-2693(95)01255-x

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