Number density map of the stellar halo in R − Z space for the BHB stars in the subsample (log₁₀ ν, left panel) and the model (log₁₀ ν_fitting, middle panel). The pixel size is 0.5 × 0.5 (kpc). The color in each pixel represents the mean density on a logarithmic scale. The residual map ((ν − ν_fitting)/ν_fitting) presented in the right panel indicates a good consistency between the data and the model, where no prominent overdensity exists in the solar neighborhood and the outer parts of the stellar halo.