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arXiv · 1106.4992

Negative parity baryons in the $1/N_c$ expansion: the quark excitation versus the meson-nucleon resonance picture

N. Matagne·Fl. Stancu
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Abstract

In order to better understand the fundamental issue regarding the compatibility between the quark-shell picture and that of resonances in meson-nucleon scattering in large $N_c$ QCD we extend the work of Cohen and Lebed on mixed symmetric $\ell $ = 1 baryons to analyze excited states with $\ell $ = 3. We give an explicit proof on the degeneracy of mass eigenvalues of a simple Hamiltonian including operators up to order $\mathcal{O}(N^0_c)$ \emph{i. e.} neglecting $1/N_c$ corrections in the quark-shell picture in the large $N_c$ limit. We obtain three degenerate multiplets formed of $\ell = 3$ states, as in the case of $\ell $ = 1 baryons. The compatibility between this picture and that of resonances in meson-nucleon scattering is discussed in the light of the present results.

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N. Matagne, Fl. Stancu. 2011-09-21. Negative parity baryons in the $1/N_c$ expansion: the quark excitation versus the meson-nucleon resonance picture. https://doi.org/10.1103/physrevd.84.056013

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