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The Hypercentral Constituent Quark Model

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

The hypercentral constituent quark model contains a spin independent three-quark interaction inspired by lattice QCD calculations which reproduces the average energy of SU(6) multiplets. The splittings are obtained with a residual generalized SU(6)-breaking interaction including an isospin dependent term. The long standing problem of the Roper is absent and all the 3- and 4-star states are well reproduced. The model has been used in a systematic way for transverse and longitudinal electromagnetic transition form factor of the 3- and 4- star and also for the missing resonances. The prediction of the electromagnetic helicity amplitudes agrees quite well with the data except for low $Q^2$, showing that it can supply a realistic set of quark wave functions. In particular we report the calculated helicity amplitude $A_{1/2}$ for the $S11(1535)$, which is in agreement with the TJNAF data.

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M. M. Giannini, E. Santopinto, A. Vassallo. 2003-01-27. The Hypercentral Constituent Quark Model. https://doi.org/10.1142/9789812704887_0055

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