EXPLORING THE CORRELATIONS BETWEEN GLOBULAR CLUSTER POPULATIONS AND SUPERMASSIVE BLACK HOLES IN GIANT GALAXIES

This paper presents an analysis of the correlation between the number of globular clusters (N-GC) in giant galaxies and the mass of the galaxies' central supermassive black hole (M-SMBH). I construct a sample of 20 elliptical, spiral, and S0 galaxies with known SMBH masses and with accurately measured GC system properties derived from wide-field imaging studies. The coefficients of the best-fitting N-GC-M-SMBH relation for the early-type galaxies are consistent with those from previous work but in some cases have smaller relative errors. I examine the correlation between N-GC and M-SMBH for various subsamples and find that elliptical galaxies show the strongest correlation, while S0 and pseudobulge galaxies exhibit increased scatter. I also compare the quality of the fit of the numbers of metal-poor GCs versus SMBH mass and the corresponding fit for metal-rich GCs. I supplement the 20 galaxy sample with 10 additional galaxies with reliable N-GC determinations but without measured M-SMBH. I use this larger sample to investigate correlations between N-GC and host galaxy properties like total galaxy luminosity and stellar mass, and bulge luminosity and mass. I find that the tightest correlation is between N-GC and total galaxy stellar mass. This lends support to the notion that N-GC and M-SMBH are not directly linked but are correlated because both quantities depend on the host galaxy potential. Finally, I use the N-GC-M-SMBH relation derived from the 20 galaxy sample to calculate predicted M-SMBH values for the 10 galaxies with accurate N-GC measurements but without measured SMBH masses.