CMD, spatial distribution, radial velocity, and metallicity distribution of the cluster and extra-tidal candidates based on Gaia EDR3 photometry (Gaia Collaboration 2021). The gray crosses in the upper left panel represents cluster stars that are located within 1 r_t and whose star PM matches that of the GC. The gray points in the upper right panel represent the extra-tidal candidates selected following the method described in Sect. 2.2. The red points represent extra-tidal candidates with RV and [Fe/H] compatible with the cluster. The green circles represent 1 and 5 tidal radii, and the blue circle represents the Jacobi radius. In the bottom two panels the orange points represent stars with radial velocity and metallicity observations that do not match the cluster. The solid horizontal line represents the mean value of the cluster, and the dashed horizontal line represents the corresponding dispersion or error range for cluster. The error bar represents the observation error of the individual stars.