The Origins of Neutron-capture Elements In Globular Cluster M22

The chemical abundances of metal-poor stars in globular clusters provide important constraints on their evolutionary scenarios. Using both main r-process and weak r-process patterns, we fit the abundances of s-poor stars in the globular cluster M22. The coefficients of the main and weak r-process components are nearly constant for the sample stars, including s-rich stars. By accounting for the contribution of the s-process from low-mass asymptotic giant branch stars, the abundances of s-rich stars in M22 can also be fitted effectively. In addition, the increasing trend in the s-process component coefficients with rising [Fe/H] indicates a gradual increase in the contribution from low-mass asymptotic giant branch stars.