$χ_{c0}$ production in $\barΛn$ scattering process

Abstract

In the present work, we investigate the production of $χ_{c0}$ in the $\barΛ n \rightarrow χ_{c0} K^{0}_{S}$ process by utilizing an effective Lagrangian approach. Based on the $χ_{c0} \rightarrow n K^{0}_{S} \barΛ$ decay observed by the BESIII Collaboration, the coupling constants are determined by fitting the $M_{K^{0}_{S} \barΛ}$ and $M_{n K^{0}_{S}}$ invariant mass spectra, where eight $N$ and $Λ$ state are considered. Moreover, the parameters $β$ is taken to be 1, 2, 3 as special cases to check the parameter dependence. Our results show that two clear structures can be observed in both $M_{K^{0}_{S} \barΛ}$ and $M_{n K^{0}_{S}}$ invariant mass spectra, which should correspond to $N(1720)/N(1895)$ and $Λ(1600)/Λ(1890)$, respectively. In addition, the contributions from $N(938)$ and $Λ(1116)$ intermediate states are much smaller than those of the above-threshold resonances. With the fitted parameters for $β=1$, 2, 3, the cross sections for $\barΛ n \rightarrow χ_{c0} K^{0}_{S}$ are estimated to be 1.9 nb, 4.2 nb, and 8.0 nb at $\sqrt{s}=6$ GeV, respectively. Furthermore, our estimations indicate that the differential cross sections for $\barΛ n \rightarrow χ_{c0} K^{0}_{S}$ reach a maximum in the forward angle region.