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Nucleon form factors and a nonpointlike diquark

J. C. R. Bloch·C. D. Roberts·S. M. Schmidt·A. Bender·M. R. Frank
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Abstract

Nucleon form factors are calculated on q^2 in [0,3] GeV^2 using an Ansatz for the nucleon's Fadde'ev amplitude motivated by quark-diquark solutions of the relativistic Fadde'ev equation. Only the scalar diquark is retained, and it and the quark are confined. A good description of the data requires a nonpointlike diquark correlation with an electromagnetic radius of 0.8 r_pi. The composite, nonpointlike nature of the diquark is crucial. It provides for diquark-breakup terms that are of greater importance than the diquark photon absorption contribution.

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J. C. R. Bloch, C. D. Roberts, S. M. Schmidt, A. Bender, M. R. Frank. 1999-07-30. Nucleon form factors and a nonpointlike diquark. https://doi.org/10.1103/physrevc.60.062201

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