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arXiv · hep-ph/0103171

N^* electroproduction amplitudes in a model with dynamical confinement

P. Alberto·M. Fiolhais·B. Golli·J. Marques
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Abstract

The Roper resonance is described in a chiral version of the chromodielectric model as a cluster of three quarks in radial-orbital configuration (1s)$^2$(2s)$^1$, surrounded by $π$ and $σ$-meson clouds and by a chromodielectric field which assures quark dynamical confinement. Radial profiles for all fields are determined self-consistently for each baryon. Transverse $A_{1/2}$ and scalar $S_{1/2}$ helicity amplitudes for the nucleon-Roper transition are calculated. The contribution of glueball and $σ$-meson vibrations is estimated; although small for N(1440), the $σ$ contribution can be large for N(1710).

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P. Alberto, M. Fiolhais, B. Golli, J. Marques. 2001-10-15. N^* electroproduction amplitudes in a model with dynamical confinement. https://doi.org/10.1016/s0370-2693(01)01348-x

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