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Extra S11 and P13 in the Hypercentral Constituent Quark Model

M. M. Giannini·E. Santopinto·A. Vassallo
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Abstract

We report on the recent results of the hypercentral Constituent Quark Model (hCQM). The model contains a spin independent three-quark interaction which is inspired by Lattice QCD calculations and reproduces the average energy values of the SU(6) multiplets. The splittings within each multiplet are obtained with a SU(6)-breaking interaction, which can include also an isospin dependent term. All the 3- and 4-stars resonances are well reproduced. Moreover, as all the Constituent Quark models, the hCQM predicts ``missing'' resonances ({\em e.g.} extra $S11$ and $P13$ states) which can be of some help for the experimental identification of new resonances. The model provides also a good description of the medium $Q^2$-behavior of the electromagnetic transition form factors. In particular the calculated helicity amplitude $A_{1/2}$ for the $S_{11}(1535)$ resonance agrees very well with the recent CLAS data. More recently, the elastic nucleon form factors have been calculated using a relativistic version of the hCQM and a relativistic quark current.

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M. M. Giannini, E. Santopinto, A. Vassallo. 2003-02-10. Extra S11 and P13 in the Hypercentral Constituent Quark Model. https://doi.org/10.1142/9789812705174_0044

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