Dynamical mass measurements in the nuclear region of the Circinus galaxy. Measurements are marked by filled circles of different colors and are identified in the legend. The red filled circle represents the CRIRES spectroastrometry mass measurement obtained assuming a disk with i = 61° with respect to the line of sight, same as the large-scale measurements; the open red circle represents the spectroastrometry mass measurement obtained assuming an edge-on disk, same as the maser disk. The region shaded by gray dotted lines is characterized by r < 20 mas and is the region probed by the H₂O maser rotation curve, where the dynamical mass is mostly unresolved and belongs to the BH. The enclosed mass within this region must be dominated by the BH, since no evidence for extended mass is seen in the maser rotation curve. The gray stripe represents the radial total mass distribution of the best-fit model for the CRIRES rotation curves (taking into account errors on M_UDM and M/L). The orange line represents the total mass distribution, which is a combination of BH mass, nuclear (4 pc size) and extended mass distribution, with the mass distribution derived by Müller Sanchez et al. (2006). The nuclear mass distribution corresponds to what we measure as M_UDM. The green line is similar to the orange line but the nuclear mass distribution now has a size of 2 pc. The dashed green line is the contribution of BH mass and nuclear mass distribution, while the dotted line represents the BH mass and the extended mass distribution. The continuous black line represents the radial mass distribution of the nuclear star cluster at the center of the Milky Way (Genzel et al. 2010) combined with the BH mass (Greenhill et al. 2003a) and rescaled to match the measurements at  ~10 pc scale.