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Electroproduction of the Roper resonance and the constituent quark model

F. Cardarelli·E. Pace·G. Salme'·S. Simula
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Abstract

A parameter-free evaluation of the $N - P_{11}(1440)$ electromagnetic transition form factors is performed within a light-front constituent quark model, using for the first time the eigenfunctions of a mass operator which generates a large amount of configuration mixing in baryon wave functions. A one-body electromagnetic current, which includes the phenomenological constituent quark form factors already determined from an analysis of pion and nucleon experimental data, is adopted. For $Q^2$ up to few $(GeV/c)^2$, at variance with the enhancement found in the elastic channel, the effect of configuration mixing results in a significant suppression of the calculated helicity amplitudes with respect to both relativistic and non-relativistic calculations, based on a simple gaussian-like ansatz for the baryon wave functions.

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F. Cardarelli, E. Pace, G. Salme', S. Simula. 1997-02-11. Electroproduction of the Roper resonance and the constituent quark model. https://doi.org/10.1016/s0370-2693(97)00149-4

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