Chiral unitary approach to the pi N*N*, eta N*N* couplings for the N* (1535) resonance
/ Abstract
Abstract Using a chiral unitary model in which the negative parity nucleon resonance N ∗ ≡N ∗ (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 ∗ N ∗ and ηN ∗ N ∗ couplings. The π 0 N ∗ N ∗ coupling has smaller strength but the same sign as the π 0 NN coupling. This rules out the mirror assignment of chiral symmetry where the ground state nucleon N and the negative parity resonance N ∗ are envisaged as chiral partners in the baryon sector.