Chiral unitary approach to the pi N*N*, eta N*N* couplings for the N* (1535) resonance

摘要

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 π0N∗N∗ and ηN∗N∗ couplings. The π0N∗N∗ coupling has smaller strength and the same sign as the π0NN 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.