CERES stars in the T_eff − log ɡ diagram. The BaSTI evolutionary track (blue dash-dotted line) has an α-enhanced chemical mixture and does not include rotation. Two MIST evolutionary tracks are also included for non-rotating (blue continuous line) and with rotation v_crit = 0.4 (gray dotted line). All the tracks are for M = 0.8 M_⊙ and [Fe/H] = −2.50 dex. The RGB Bump for the adopted tracks is at T_eff ~ 4880 K and log ɡ ~1.95 dex. The color index on the right side of the figure indicates the [C/N] abundance ratio. The dispersion in T_eff and log ɡ measurements is represented by the error bar in the upper left corner of the figure.