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Effective Q-Q Interactions in Constituent Quark Models

L. Ya. Glozman·Z. Papp·W. Plessas·K. Varga·R. F. Wagenbrun
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Abstract

We study the performance of some recent potential models suggested as effective interactions between constituent quarks. In particular, we address constituent quark models for baryons with hybrid Q-Q interactions stemming from one-gluon plus meson exchanges. Upon recalculating two of such models we find them to fail in describing the N and Δspectra. Our calculations are based on accurate solutions of the three-quark systems in both a variational Schrödinger and a rigorous Faddeev approach. It is argued that hybrid {Q-Q} interactions encounter difficulties in describing baryon spectra due to the specific contributions from one-gluon and pion exchanges together. In contrast, a chiral constituent quark model with a Q-Q interaction solely derived from Goldstone-boson exchange is capable of providing a unified description of both the N and Δspectra in good agreement with phenomenology.

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L. Ya. Glozman, Z. Papp, W. Plessas, K. Varga, R. F. Wagenbrun. 1997-05-05. Effective Q-Q Interactions in Constituent Quark Models. https://doi.org/10.1103/physrevc.57.3406

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