Chiral-symmetry realization for even- and odd-parity baryon resonances

Baryon resonances with even and odd parity are collectively investigated from the viewpoint of chiral symmetry (ChS). We propose a quarter scheme where Delta's and N*'s with even and odd parity form a chiral multiplet. This scheme gives parameter-free constraints on the baryon masses in the quarter, which are consistent with observed masses with spin 1/2, 3/2, 5/2. The scheme also gives selection rules in the one-pion decay: The absence of the parity nonchanging decay N(1720) --> pi Delta(1232) is a typical example which should be confirmed experimentally to unravel the role of ChS Ln baryon resonances.