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Mesonic Content of the Nucleon and the Roper Resonance

M. Dillig·M. Schott
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Abstract

We investigate colorless (mesonic) 3q-q qbar components in the nucleon and the Roper resonance N*(1440). Starting from constituent quarks and gluons we estimate the excitation of quark-antiquark pairs in a gluon exchange model with the strong coupling constant extracted from a comparison with a non-perturbative resonating group calculation of the pi, eta, rho and omega content of the nucleon. Applying the same model to the Roper resonance, we find as the most striking result a very strong scalar-isoscalar sigma content of the N*(1440) with a strength of the 3q-q qbar configurations comparable to the 3q component itself.

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M. Dillig, M. Schott. 2006-04-24. Mesonic Content of the Nucleon and the Roper Resonance. https://doi.org/10.1103/physrevc.75.067001%2010.1103%2Fphysrevc.76.019903

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