Supermassive Black Holes in Nuclear Star Clusters

I will present a search for spectroscopic evidence of supermassive black holes (SMBHs) in a sample of low-mass galaxies with nuclear star clusters (NSC). It was previously thought that NSCs and SMBHs were mutually exclusive, but it is now theorized that NSCs may facilitate the formation of a SMBH. I am analyzing 38 galaxies that have preliminary X-ray evidence for a SMBH in a NSC, from Baldassare et al. 2022. I'm looking for optical spectroscopic emission lines that indicate photoionization from an active SMBH. Preliminary analysis shows that at least 40% of these objects have optical spectroscopic evidence for a SMBH. If we find emission lines characteristic of a BH in these galaxies, we will strongly increase the number of galaxies known to contain both a SMBH and NSC and improve our understanding of how SMBHs form.