Projected density distribution of RRab stars. The colour-coding is the same as in Fig. 1. The solid black line shows the power-law fit for the innermost area of R <  2.2°. The black semi-dashed line and black dotted line show the power law for 2.2° < R < 8.0° and 8.0° < R < 30.0°, respectively. The open circles are the expected location of the Sgr dwarf galaxy (R > 23°), so these data points are not included in the fitting procedure. The radius is at half maximum density R_{Σ RRab} < 1.7° (R_{Σ RRab} < 0.25 kpc). The top axis shows the distance in kiloparsecs. The conversion from degrees to kiloparsecs is made assuming that the distance to the Galactic centre is R_⊙ = 8.33 kpc from Dékány et al. (2013).