$Λ(1405)$ production in the process $χ_{c0}(1P)\to \barΛΣπ$

Abstract

We have performed a theoretical study on the process $χ_{c0}(1P)\to \barΛΣπ$, by taking into account the final state interactions of $πΣ$ and $π\barΛ$ based on the chiral unitary approach. As the isospin filters of $I=0$ in the $πΣ$ channel and $I=1$ in the $π\barΛ$ channel, this process can be used to study the molecular structure of the $Λ(1405)$ resonance, and to test the existence of the predicted states $Σ(1380)$ and $Σ(1430)$ with spin-parity $J^P=1/2^-$. Our results show that there is a peak around $1350 \sim 1400$~MeV, and a cusp around the $\bar{K}N$ threshold in the $πΣ$ invariant mass distribution, which should be the important feature of the molecular state $Λ(1405)$. We also find a peak around $1380$~MeV, and a cusp around $\bar{K}N$ threshold in the $π\barΛ$ invariant mass distribution, which are associated to the $Σ(1380)$ and $Σ(1430)$ resonances.