A Population of Luminous Globular Clusters and Stripped Nuclei with Elevated Mass to Light Ratios around NGC 5128*

The dense central regions of tidally disrupted galaxies can survive as ultra-compact dwarfs (UCDs) that hide among the luminous globular clusters (GCs) in halo massive galaxies. An exciting confirmation this model is detection overmassive black holes centers some UCDs, which also lead to elevated dynamical mass-to-light ratios ($M/L_{dyn}$). Here we present new high-resolution spectroscopic observations 321 GC candidates galaxy NGC 5128/Centaurus A. Using these data confirm 27 GCs, and measure velocity dispersions for 57 GCs (with $g$-band luminosities between $2.5 \times 10^5$ 10^7 L_{\odot}$), 48 are measurements. Combining with size measurements from Gaia, determine $M/L_{dyn}$ all GCs. We see a clear bimodality distribution, population normal mean $M/L_{dyn}=1.51\pm0.31$, second $\sim$20 $M/L_{dyn}=2.68\pm0.22$. show masses $\sim4$-18 % explain ratios. Hence, it plausible 5128 sources mostly stripped nuclei contain holes, though future high spatial resolution necessary hypothesis individual sources. detailed discussion an extreme outlier, \textit{VHH81-01}, one largest most 5128, making exceptionally strong candidate be nucleus.