CMDs with the color indices of gi minus JHK_s band and gi magnitudes. The colored dots are the stars that are brighter than the TRGB magnitude (K_s = 18.2), which corresponds to the slanted line in the (g − Ks,g) CMD. The Galactic foreground and supergiants stars are indicated by the blue and orange dots, respectively. The green and red dots correspond to the M-giant and C stars. The red curves in the (g − Ks,g) CMD are isochrones (Girardi et al. 2010) for the metallicity of Z = 0.001 with an age of log (t_yr) = 9.0,9.4.