PM measured at (l,b) = (0, −6) field for bulge RC stars. The blue and red dots identify the selected BRC and FRC stars on the CMD, respectively. A 3σ selection (lower right panel) in the μ_lcos   (b) and μ_b plane is used to define the sample further analyzed with histograms. The lower left panel shows μ_b distribution, while the upper right panel compares μ_lcos   (b) distributions for the BRC and FRC stars. The mean values of μ_lcos   (b) and μ_b for the BRC and FRC samples are given in the respective panels showing the distributions, and we also provide the mean differences in proper motion for the two RC populations.