Role of the $N^{\ast }(1535)$ in the ${\Lambda }_c^{+}\to {\bar{K}}^0\eta p$ decay

Abstract

The nonleptonic weak decay of ${\Lambda }_c^{+}\to {\bar{K}}^0\eta p$ is analyzed from the viewpoint of probing the $N^{\ast }(1535)$ resonance, which has a big decay branching ratio to $\eta N$. Up to an arbitrary normalization, the invariant mass distribution of $\eta p$ is calculated with both the chiral unitary approach and an effective Lagrangian model. Within the chiral unitary approach, the $N^{\ast }(1535)$ resonance is dynamically generated from the final state interaction of mesons and baryons in the strangeness zero sector. For the effective Lagrangian model, we take a Breit-Wigner formula to describe the distribution of the $N^{\ast }(1535)$ resonance. It is found that the behavior of the $N^{\ast }(1535)$ resonance in the ${\Lambda }_c^{+}\to {\bar{K}}^0{N}^{\ast }(1535)\to {\bar{K}}^0\eta p$ decay within the two approaches is different. The proposed ${\Lambda }_c^{+}$ decay mechanism can provide valuable information on the properties of the $N^{\ast }(1535)$ and can in principle be tested by facilities such as BEPC II and SuperKEKB.

Comments: 8 pages and 7 figures