Do Nuclear Star Clusters and Supermassive Black Holes Follow the Same Host-Galaxy Correlations?

Figure 4

Relative masses of NSCs versus Hubble type of host galaxy, based on the compilation of Seth et al. [48]. Filled gray circles are NSC masses estimated from broadband colors or assumed 𝑀/𝐿 ratios by Seth et al [29]; red stars indicate NSC masses from spectroscopic (hollow) or dynamical (filled) measurements (see Table 2 for references). Also shown are simple fits to the dynamical+spectroscopic masses (dashed red line) and to the entire sample (dashed gray line), along with the mean mass ratio of SMBHs relative to their host bulges (dotted gray line).