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Chiral Unitary Approach To The N*N*pi, N*N*eta Couplings For The N*(1535) Resonance

J. C. Nacher·A. Parreno·E. Oset·A. Ramos·A. Hosaka·M. Oka
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Abstract

Using a chiral unitary model in which the negative parity nucleon resonance $N^\ast \equiv N^\ast(1535)$ is generated dynamically by means of the Bethe Salpeter equation with coupled meson baryon channels in the $S = 0$ sector, we have obtained the $π^0 N^\ast N^\ast$ and $ηN^\ast N^\ast$ couplings. The $π^0 N^\ast N^\ast$ coupling has smaller strength and the same sign as the $π^0 N N$ coupling. This rules out the mirror assignment of chiral symmetry where the ground state nucleon $N$ and the negative parity resonance $N^\ast$ are envisaged as chiral partners in the baryon sector.

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J. C. Nacher, A. Parreno, E. Oset, A. Ramos, A. Hosaka, M. Oka. 2000-05-31. Chiral Unitary Approach To The N*N*pi, N*N*eta Couplings For The N*(1535) Resonance. https://doi.org/10.1016/s0375-9474(00)00311-0

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