Theoretical study of N (1535) and ^* (1/2^-) in the Cabibbo-favored process c^+ p K⁰

Motivated by the recent experimental measurements, we have investigated the Cabibbo-favored process c^+ p K⁰, where the N (1535) resonance is dynamically generated from the S-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach. The contributions from the intermediate N (1650) and the predicted low-lying baryon ^* (1/2^-) are also considered. In addition, a Breit-Wigner amplitude for the N (1535) resonance is checked. By comparing with the measured p, K⁰, and p K⁰ invariant mass squared distributions, our results support the interpretation of N (1535) as a dynamically generated state. Furthermore, we demonstrate that, with the contribution from ^* (1/2^-) taken into account, the calculated invariant mass spectrum agrees with the Belle measurements. Future precise measurements of the c^+ p K⁰ process can further elucidate the existence of the low-lying baryon ^* (1/2^-).