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

Antoine Dumont, Anil C. Seth, Jay Strader, Karina Voggel, David J. Sand, Allison K. Hughes, Nelson Caldwell, Denija Crnojević, Mario Mateo, John I. Bailey, et al.

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## To cite this version:

Antoine Dumont, Anil C. Seth, Jay Strader, Karina Voggel, David J. Sand, et al.. A Population of Luminous Globular Clusters and Stripped Nuclei with Elevated Mass to Light Ratios around NGC 5128. The Astrophysical Journal, 2022, 929, 10.3847/1538-4357/ac551c. insu-03668896

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Submitted on 16 May 2022

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

Antoine Dumont<fnref n="1" />, Anil C. Seth<fnref n="1" />, Jay Strader<fnref n="2" />, Karina Voggel<fnref n="3" />, David J. Sand<fnref n="4" />, Allison K. Hughes<fnref n="4" />, Nelson Caldwell<fnref n="5" />, Denija Crnojević<fnref n="6" />, Mario Mateo<fnref n="2" />, John I. Bailey, III<fnref n="7" />, and Duncan A. Forbes<fnref n="8" />

Received 2021 September 30; revised 2022 January 5; accepted 2022 January 19; published 2022 April 21

## Abstract

The dense central regions of tidally disrupted galaxies can survive as ultracompact dwarfs (UCDs) that hide among the luminous globular clusters (GCs) in the halo of massive galaxies. An exciting confirmation of this model is the detection of overmassive black holes in the centers of some UCDs, which also lead to elevated dynamical mass-to-light ratios ($M/L_{dyn}$). Here we present new high-resolution spectroscopic observations of 321 luminous GC candidates in the massive galaxy NGC 5128/Centaurus A. Using these data we confirm 27 new luminous GCs, and measure velocity dispersions for 57 luminous GCs (with g-band luminosities between $2.5 \times 10^5$ and $2.5 \times 10^7 L_\odot$), of which 48 are new measurements. Combining these data with size measurements from Gaia, we determine the $M/L_{dyn}$ for all 57 luminous GCs. We see a clear bimodality in the $M/L_{dyn}$ distribution, with a population of normal GCs with mean $M/L_{dyn} = 1.51 \pm 0.31$, and a second population of ~20 GCs with elevated mean $M/L_{dyn} = 2.68 \pm 0.22$. We show that black holes with masses ~4%–18% of the luminous GCs can explain the elevated mass-to-light ratios. Hence, it is plausible that the NGC 5128 sources with elevated $M/L_{dyn}$ are mostly stripped galaxy nuclei that contain massive central black holes, though future high spatial resolution observations are necessary to confirm this hypothesis for individual sources. We also present a detailed discussion of an extreme outlier, VHH81-01, one of the largest and most massive GC in NGC 5128, making it an exceptionally strong candidate to be a tidally stripped nucleus.

Unified Astronomy Thesaurus concepts: Ultracompact dwarf galaxies (1734); Globular star clusters (656); Mass-to-light ratio (1011); Galaxy nuclei (609); Stellar kinematics (1608); Stellar dynamics (1596)

Supporting material: machine-readable tables

## 1. Introduction

A majority of lower-mass galaxies host dense nuclear star clusters (Neumayer et al. 2020). During merging, the tidal forces of a larger galaxy can strip away the contents of a smaller one, leaving behind these nuclear star clusters to orbit in the halo of the larger galaxy as a stripped galaxy nucleus (e.g., Pfeffer & Baumgardt 2013). Such stripped galaxy nuclei can be challenging to distinguish from massive globular clusters (GCs). The collection of massive GCs and stripped galaxy nuclei is often referred to as ultracompact dwarf galaxies (UCD). The physical definition of UCDs varies widely in the literature (e.g., Mieske et al. 2013; Liu et al. 2015), but commonly refers to objects with $\gtrsim 2 \times 10^6 M_\odot$ and half-light radii of $\gtrsim 7–10$ pc (e.g., Mieske & Kroupa 2008; Forbes & Kroupa 2011). However, nuclear star clusters extend down to

lower masses and sizes than commonly used cutoffs for defining UCDs and can overlap in mass and size with GCs (Neumayer et al. 2020). Thus the definitions of UCDs neither exclude all massive GCs nor include all stripped nuclei. Because of the ambiguity in the classification of UCDs, throughout this paper we use the term luminous GCs. These luminous GCs refer to both massive GCs and stripped galaxy nuclei without assuming a specific mass, luminosity, or size cut.

A large number of stripped nuclei are expected around massive galaxies and in galaxy clusters due to the hierarchical nature of galaxy merging. Simulations are consistent with most of the higher mass GCs ($\gtrsim 10^7 M_\odot$) in clusters being stripped galaxy nuclei (Pfeffer et al. 2016; Norris et al. 2019; Mayes et al. 2021). They also suggest that lower-mass galaxies will contain lower-mass stripped nuclei, and that the Milky Way may contain 2–6 stripped nuclei (Pfeffer et al. 2014; Kruijssen et al. 2019).

Stripped nuclei can be distinguished observationally from normal GCs due to their lives at the centers of galaxies; this can result in extended star formation and the growth of massive black holes (e.g., Neumayer et al. 2020). Within the Milky Way, evidence for large metallicity and age spreads is seen in

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Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

<footnote n="1">¹Department of Physics and Astronomy, University of Utah 115 South 1400 East, Salt Lake City, UT 84112, USA; antoine.dumont.neira@hotmail.com, seth@astro.utah.edu</footnote>

<footnote n="2">²Department of Physics and Astronomy Michigan State University Biomedical & Physical Sciences 567 Wilson Rd, Room 3275 East Lansing, MI 48824-2320, USA; strader@pa.msu.edu</footnote>

<footnote n="3">³Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, F-67000 Strasbourg, France</footnote>

<footnote n="4">⁴Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA</footnote>

<footnote n="5">⁵Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA</footnote>

<footnote n="6">⁶University of Tampa, 401 West Kennedy Boulevard, Tampa, FL 33606, USA</footnote>

<footnote n="7">⁷Department of Physics & Astronomy, Broida Hall, University of California, Santa Barbara, CA 93106, USA</footnote>

<footnote n="8">⁸Centre for Astrophysics & Supercomputing, Swinburne University, Hawthorn, VIC 3122, Australia</footnote>

<footnote>* This paper includes data gathered with the 6.5 m Magellan Telescope at Las Campanas Observatory, Chile.</footnote>
several luminous GCs, including ω Cen (e.g., Johnson & Pilachowski 2010; Villanova et al. 2014), which appears to be the nucleus of a significant building block of the Milky Way (Forbes 2020; Pfeffer et al. 2021), and M54 (Siegel et al. 2007; Alfaro-Cuello et al. 2019), which is the nucleus of the currently infalling Sagittarius dwarf galaxy. An extended star formation history has also been seen in a massive (3 × 10⁷ M☉) UCD around NGC 4546 (Norris et al. 2015).

It is now well established that supermassive black holes are common at the centers of galaxies with stellar mass $M_\star > 10^9 M_{\odot}$, including those with nuclear star clusters (Miller et al. 2015; Nguyen et al. 2018, 2019; Greene et al. 2020). Thus we expect stripped nuclei to host massive black holes as well. Supermassive black holes (SMBHs) have been dynamically detected in all five massive UCDs ($>10^7 M_{\odot}$) with available high spatial resolution integral field spectroscopic data (Seth et al. 2014; Ahn et al. 2017, 2018; Afanasiev et al. 2018). The black holes in these UCDs typically make up ~10% of their total stellar mass, similar to the mass fraction of the SMBH in the nuclear star cluster of the Milky Way (Neumayer et al. 2020). As noted above, simulations suggest that all UCDs in this mass range should be stripped nuclei (Pfeffer et al. 2016; Mayes et al. 2021). These same simulations suggest that many stripped nuclei should have lower masses as well ($<10^7 M_{\odot}$). The star formation histories of ω Cen and M54 discussed above confirm that there are stripped nuclei at lower masses, as does the recent detection of a ~$10^5 M_{\odot}$ black hole in Andromeda's most massive GC (Pechetti et al. 2022).

There have also been many claims of detections of $\lesssim 10^4 M_{\odot}$ black holes at the centers of Milky Way GCs (see recent review by Greene et al. 2020). However, none of these claims is regarded as robust (e.g., Zocchi et al. 2019; Hénault-Brunet et al. 2020), and no accretion evidence for any intermediate mass black holes in Milky Way GCs have been found (Tremou et al. 2018). The claimed detections and upper limits for these black holes correspond to mass fraction of 0.1%–1% of the total mass of the cluster. Theoretically, there are processes that may form intermediate mass black holes during the formation and evolution of GCs, including the merging of massive stars early in the life of the cluster or the merging of stellar mass black holes over time (e.g., Portegies Zwart et al. 2004; Inayoshi et al. 2020; Di Carlo et al. 2021). However, these mechanisms produce small black holes that make up <1% of the total mass of the cluster; thus the black holes found in UCDs are mostly far too massive to result from these processes without significant subsequent accretion that is unlikely outside a nuclear environment. Therefore, the detection of high mass fraction black holes in luminous GCs provides strong evidence that they are stripped nuclei. At the same time, as we discuss below, these high mass fraction black holes are not expected in all stripped nuclei.

Even before SMBHs were detected in UCDs, there was indirect evidence of their existence. Central black holes raise the velocity dispersion of stars near the center of the stripped nuclei, elevating the apparent dynamical mass-to-light ratio derived from integrated dispersion measurements relative to the expected mass-to-light ratio from stellar populations (e.g., Mieske et al. 2013; Forbes et al. 2014). The enhanced mass-to-light ratio was used by Mieske et al. (2013) to predict the central black hole mass in UCDs with integrated dispersion measurements; they found similar mass fractions in many objects to the SMBH detections from resolved kinematics

discussed above. More recently, Voggel et al. (2019) used the inflated mass-to-light ratio measurements to quantify the fraction of luminous GCs that have high mass fraction black holes (and thus are likely stripped nuclei) as a function of luminosity; they find that ~20% of luminous GCs at $10^6 L_{\odot}$ have evidence for black holes, rising to >70% at the highest luminosities. This implies that a significant fraction of massive black holes in the local universe may be present outside of galaxy nuclei, a finding also shared by recent works (Greene et al. 2020; Ricarte et al. 2021). We expect a majority of these black holes in stripped nuclei to reside in lower luminosity nuclei than those that have currently been dynamically confirmed. Dynamical detection of smaller black holes in Virgo is not possible with current technology; thus finding candidates of these lower-mass stripped nuclei in nearby galaxies is important.

In this paper, we focus on finding additional candidate luminous GCs that may be stripped nuclei and have inflated mass-to-light ratios. We use high-resolution spectroscopic data to derive internal velocity dispersion measurements and present size estimates for a new sample of luminous GC candidates around NGC 5128 (hereafter Cen A). These luminous GCs extend out to 150 kpc in Cen A's halo and are compiled from the candidates of Voggel et al. (2020) and Hughes et al. (2021), making it the largest and most complete study of luminous GC velocity dispersions in the outskirts of Cen A. Using the velocity dispersions and sizes, we estimate the dynamical mass-to-light ratio of each luminous GC.

The paper is organized into six sections. In Section 2 we describe the sample selection and observations. Section 3 describes our method to obtain velocity dispersion and metallicities for our luminous GCs. In Section 4 we estimate radii and V-band luminosities, and then calculate mass-to-light ratios and black hole mass predictions in Section 5. Finally, we conclude in Section 6. Throughout this paper we apply a distance modulus for Cen A of ($m-M)_0$ = 27.91 mag, corresponding to a distance of 3.8 Mpc. We correct individual objects for foreground extinction; a typical Milky Way extinction value near Cen A is $A_V$ = 0.306 mag (Schlafly & Finkbeiner 2011).

## 2. Sample Selection and Data Reduction

### 2.1. Sample Selection and Sample Completeness

Based on the catalogs of Voggel et al. (2020) (hereafter KV20) and Hughes et al. (2021), we have targeted 314 GCs and stripped nuclei candidates around Cen A's halo out to a projected distance of ~150 kpc; ~135'. KV20 is a catalog of 614 luminous GC candidates in Cen A based on Gaia DR2, and Hughes et al. (2021) is catalog of 40,502 GC candidates around Cen A based on data from the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) survey, combined with Gaia DR2 and NOAO source catalog data. Our targets span a much larger range of galactocentric distance in comparison with previous studies (e.g., Rejkuba et al. 2007).

In addition to the 314 targets from these catalogs, we have also selected two previously confirmed GCs in Cen A—*aat329848*, from Beasley et al. (2008), and *VHH81-5*, from Rejkuba et al. (2007)—to provide us with some repeat measurements for testing the robustness of our results. We also targeted four nuclear star clusters (NSCs) of known Cen A satellite galaxies (*KK197-NSC*, *ESO269-06*, *Dwl_NSC*, and *DW3* from Crnojević et al. 2014, 2016), and a diffuse cluster in
Cen A, “Fluffy,” which was found through visual inspection of PISCeS images, and whose radial velocity was presented in Voggel et al. (2020). Thus in total, we observed 321 candidate luminous GCs. Of these 321 objects, we were able to measure the radial velocity for 219 candidates, of which 165 also had measurable velocity dispersions (see Section 3.3). Based on the radial velocities, we identify 78 as being Cen A clusters, and we measure the velocity dispersion and mass-to-light ratios (Section 5) for 57 of these.

To quantify the completeness of our sample of luminous GCs around Cen A, we first look at the total sample of luminous GCs around Cen A in the literature. We use the compilation of velocity and Hubble confirmed GCs in Hughes et al. (2021) and make a magnitude cut of $g \le 19.1$ to define a clean sample of luminous GCs. This cut corresponds to $g_0 = 18.8$ and $M_V \sim -9.5$ ($L_V \sim 5 \times 10^5 L_\odot$), and is the same cut used by KV20. We also confirm here 13 clusters from KV20 as Cen A GCs based on their radial velocities. Thus in total there are 118 clusters with $g \le 19.1$ with confirmed radial velocities in the literature. Of these 118 GCs with $g \le 19.1$, 27 have previous reliable velocity dispersion measurements (Harris et al. 2002; Martini & Ho 2004; Rejkuba et al. 2007), while in this work we present 36 new measurements as well as remeasuring dispersions in 10 objects. Thus in total, 63 of the 118 GCs with $g \le 19.1$ now have reliable velocity dispersion measurements. We also measure dispersions for 9 Cen A GCs and 2 additional nuclear star clusters at $g > 19.1$. Also, in the calculation above we exclude the large number of dispersion measurements from Taylor et al. (2010) and Taylor et al. (2015), because the median signal-to-noise ratio (S/N) of their measurements is very low (2 for Taylor et al. 2015), well below the limit where we find we can reliably measure dispersions using similar high-resolution spectroscopy. Just a handful of their measurements have S/N in the range of the measurements we present here. Issues with both their published velocities and dispersions have been documented previously (Voggel et al. 2018, 2019), and we find additional issues that we identify below.

We can also estimate the total number of luminous GCs in Cen A based on our confirmation of KV20 candidates. The KV20 sample is a nearly complete catalog of new luminous GC candidates at galactocentric radii beyond 5.5 kpc. Figure 1 shows the results of how many of our observed targets are confirmed as Cen A clusters based on their radial velocities (see Section 3.3). Using these data for the different ranks of cluster candidates in KV20, we estimate there are a total of ~31 real Cen A GCs in the catalog, of which we have found 13 so far. Combined with previously identified clusters that likely form a complete sample at smaller radii, we estimate a total of ~136 total luminous GCs with $g \le 19.1$ around Cen A.

Throughout this paper, we use photometry for our sources from the NOAO DR2 source catalog (Nidever & Astro Data Lab team 2020). This photometry in ugriz is derived from DECam observations, and appears to be more reliably calibrated and more complete than photometry from the same data presented in Taylor et al. (2017). Throughout this paper, we present magnitudes corrected for galactic extinction using Schlafly & Finkbeiner (2011).

## 2.2. Spectroscopic Data of Luminous GC Candidates

The observations of 321 GC candidates in Cen A were taken over several observing runs between 2017 February and 2019

<figure><img src="image_5.png" /><figcaption>**Figure 1.** Histogram of 321 luminous GCs candidates in our sample categorized as Cen A Objects and Non Cen A Objects based on their radial velocities. We consider objects with $RV \ge 250$ km s$^{-1}$ to be Cen A objects, while those with $RV \le 250$ km s$^{-1}$ respectively are likely Milky Way foreground stars (see Section 3.3 for details). RankA-E KV20 correspond to objects from the Voggel et al. (2020) catalog, with the A ranked objects being the highest likelihood to be GCs in Cen A. We also show objects with previous radial velocity and/or velocity dispersion ($\sigma$) measurements.</figcaption></figure>

<table><caption>**Table 1**
Observation Log</caption><thead><tr><th>Observation</th><th>Instr.</th><th>Setup</th><th>ExpTime (minute)</th><th>Seeing (")</th><th>Obs Date mm/dd/yyyy</th></tr></thead><tbody><tr><td>FieldMG 0</td><td>M2FS</td><td>Mg</td><td>4 × 45</td><td>0.65</td><td>02/24/2017</td></tr><tr><td>FieldMG 1</td><td>M2FS</td><td>Mg</td><td>4 × 45</td><td>0.9</td><td>05/20/2017</td></tr><tr><td>FieldMG 2</td><td>M2FS</td><td>Mg</td><td>4 × 45</td><td>1.2</td><td>05/21/2017</td></tr><tr><td>FieldMG 3</td><td>M2FS</td><td>Mg</td><td>4 × 40</td><td>0.77</td><td>05/30/2017</td></tr><tr><td>FieldMG 4</td><td>M2FS</td><td>Mg</td><td>4 × 48</td><td>0.8</td><td>06/03/2017</td></tr><tr><td>FieldMG 6</td><td>M2FS</td><td>Mg</td><td>3 × 50</td><td>1.1</td><td>05/11/2018</td></tr><tr><td>FieldCa 1</td><td>M2FS</td><td>Ca</td><td>3 × 40</td><td>0.7</td><td>02/26/2019</td></tr><tr><td>FieldCa 2</td><td>M2FS</td><td>Ca</td><td>3 × 67</td><td>0.7</td><td>03/01/2019</td></tr><tr><td>FieldCa 3</td><td>M2FS</td><td>Ca</td><td>3 × 34</td><td>0.7</td><td>03/04/2019</td></tr><tr><td>Night 1</td><td>MIKE</td><td>Full</td><td>180</td><td>0.85-1.02</td><td>06/17/2018</td></tr><tr><td>Night 2</td><td>MIKE</td><td>Full</td><td>270</td><td>0.7-1.2</td><td>04/05/2019</td></tr><tr><td>Night 3</td><td>MIKE</td><td>Full</td><td>405</td><td>0.8-1</td><td>04/06/2019</td></tr></tbody></table>

**Note.** Mg and Ca in column 3 refer to M2FS Magnesium and Calcium Triplets setup respectively. MIKE delivers full wavelength range coverage that includes Magnesium Triplet and Calcium Triplet and is denoted here as “Full” (see Section 2.2). Column 4 shows the number of exposures times the exposure time. For MIKE observations, each individual object has a different exposure time, and we show only the combined exposure time.

March using the Michigan/Magellan Fiber System (M2FS) and the Magellan Inamori Kyocera Echelle (MIKE) spectrograph at the 6.5 m Magellan Clay telescope at Las Campanas Observatory, Chile. The list of M2FS plates and nights of MIKE observations are shown in Table 1.

M2FS is a fiber-fed double spectrograph optimized to operate from 3700–9500 Å (Mateo et al. 2012). Each spectrograph is fed by 128 fibers with a diameter of $1''$. M2FS’s large field of view (30' diameter) and its high spectral resolution ($R \sim 25,000$; ~10 km s$^{-1}$) are a perfect combination
to resolve the velocity dispersions of multiple GCs candidates simultaneously.

MIKE is a single slit echelle, double arm spectrograph, delivering full wavelength coverage from 3350–5000 Å (blue) and 4900–9500 Å (red) (Bernstein et al. 2003). We used a 1" slit width to obtain a spectral resolution of $R \simeq 22,000$; ~13 km s⁻¹ across the full wavelength range.

Our observation plan was to use M2FS for regions around Cen A where three or more high-priority luminous GC candidates (see below) are observable simultaneously, and target the rest of the high-priority candidates individually with MIKE. For targets observed with M2FS we used two distinct setups. First we observed using the MG_Wide filter, providing 4 orders ranging from 5119 to 5443 Å (hereafter Magnesium Triplet). We focused our analysis of these spectra on the second order spanning 5133–5218 Å, where the magnesium triplet lines (5167, 5172, 5183 Å) are located. The second setup uses the CaIRT₀₄₁ filter covering a single order 8471–8819 Å, which includes the “Calcium Triplet” lines at 8498, 8542, and 8662 Å. The Calcium Triplet setup provides higher S/N relative to the Magnesium Triplet but with stronger sky lines. These data allowed us to derive dispersions for fainter candidates. The MIKE data simultaneously provide full wavelength coverage from 3350–9500 Å. Our kinematic analysis of the MIKE data focused on the same regions studied with M2FS, specifically the Magnesium Triplet order covering 5140–5260 Å, and for the Calcium Triplet we use the order covering 8461–8708 Å.

The seeing for the observations was determined from the Las Campanas differential image motion monitor (DIMM) seeing monitor measurements during M2FS observations, and from direct measurements for the MIKE observations. The seeing is given in Table 1.

## 2.3. M2FS Data Reduction

The data reduction for M2FS was done using a combination of tasks in IRAF following the manual by Christian I. Johnson.<fnref n="9" />

The data reduction of the science frames requires a set of flat-fields, Thorium-Argon lamps, and bias frames for calibration. Each image observed with the CCD camera in M2FS is read out through four amplifiers that split the image into four frames. Each amplifier’s frame needs to be trimmed to remove the overscan region, bias subtracted, and rotated to be correctly oriented to join them into a single frame. We then remove cosmic rays from the combined images using the IRAF routine *L.A cosmic*.

At this point the images are ready for data reduction with DOHYDRA. DOHYDRA is a sophisticated script optimized for the reduction of data from the Wisconsin Indiana Yale NOAO (WIYN) and the Blanco Hydra spectrographs, but it can also be used for the data reduction of any similar multi-fiber spectrograph, such as the M2FS. The first step in DOHYDRA is the fiber identification using the luminous twilight spectrum in the flat-fields. For the Magnesium Triplet setup, each individual fiber has four orders on the detector; thus only 32 objects per plate are observable. For the Calcium Triplet setup, each fiber has only a single order, enabling observations of 128 separate objects per plate. For the Calcium Triplet we trace every fiber, because each fiber corresponds to a single target. For the Magnesium triplet we trace only the second order, because this

<figure><img src="image_6.png" /></figure>

**Figure 2.** Summary of S/N and NOAO DR2 *g* magnitude for the 321 observed luminous GC candidates. We measure the S/N as the median of the S/N per pixel across the full wavelength range observed. We identify candidates observed with M2FS in the Magnesium Triplet with triangular markers and in the Calcium Triplet with pentagon markers, and targets observed with the MIKE Calcium Triplet with square markers. Red objects represent targets that have visually verified radial velocities and velocity dispersions, while blue objects have only visually verified radial velocities. Gray objects are targets for which we cannot obtain kinematic measurements. Solid and open markers represent targets with radial velocity consistent with Cen A or foreground stars respectively.

corresponds to the wavelength range with the Magnesium Triplet lines.

Typically flat-fielding would be performed next; however, we found that flat-fielding resulted in noisier spectra. For that reason we did not correct for the flat-fields, because accurate flux calibration is not important for our kinematic measurements. Finally, wavelength calibration was done using a Thorium-Argon (ThAr) lamp atlas (Palmer & Engleman 1983) to identify lines in the lamp frames. The typical rms of our wavelength solution was about a third of a pixel; the pixel size in the Calcium Triplet order is 0.11 Å, whereas for the Magnesium Triplet it is 0.06 Å. For the Calcium order data, the strong sky lines enabled us to check our wavelength solution—we find a standard deviation of the line wavelengths relative to expected of 0.076 Å, suggesting an absolute velocity error of <3 km s⁻¹. No sky subtraction was performed (instead we fit the sky during our kinematic fits; see Section 3.3).

After the data reduction with DOHYDRA was completed, we summed the spectra from multiple exposures into a single spectrum in Python for each object to increase the S/N. Additionally, DOHYDRA returns an error spectrum for each exposure. We summed in quadrature the error spectra of multiple exposures to create a single error spectrum.

A total of 301 targets were observed with M2FS, of them 116 in the Magnesium Triplet, and 185 in the Calcium Triplet setup. Our targets are brighter in the Calcium Triplet, providing significantly higher S/N than the Magnesium Triplet order. The 301 M2FS targets span a range of *g* absolute magnitude of −12.8 to −5.3 mag, with a median of −9.5. Figure 2 shows the S/N ratio and *g* mag brightness for all our luminous GC candidates. For the five luminous GCs with large discrepancies between the NOAO DR2 and Gaia photometry (see Appendix),

<footnote n="9">⁹ https://www.cfa.harvard.edu/oir/m2fsreduction.pdf</footnote>
we present estimated g-band magnitudes based on the median $g-V$ color ($g-V=0.18$) of the rest of our luminous GC candidates.

## 2.4. MIKE Data Reduction

We observed 20 luminous GC candidates with MIKE, along with 22 known foreground stars on two nights from 2019 April 5–7 and on one night on 2018 June 16–17. The spectra were reduced with the CarPy reduction pipeline (Kelson et al. 2000; Kelson 2003). The pipeline automatically applies all the standard steps of applying the bias and flat-field to the data. In addition, it directly takes care of the sky subtraction as well as the rectification of the distorted spectra and cosmic ray removal.

The S/N for the MIKE Calcium Triplet data as a function of g-band magnitude is shown in squares in Figure 2. The 20 MIKE targets span a range of g absolute magnitude of −12.6 to −9.2 mag. Additionally, we had access to the fully reduced MIKE spectra of 14 luminous Cen A GCs from Martini & Ho (2004), used for testing our spectral fits (see Section 3.3).

# 3. Kinematic and Metallicity Measurements

## 3.1. Template Selection

We fitted the spectra of every candidate observed with M2FS and MIKE using the Penalized Pixel-Fitting pPXF routine (Cappellari 2017). pPXF requires a set of templates to model the spectra. We used the high-resolution ($R=500,000$) synthetic stellar templates from the Phoenix library (Husser et al. 2013). We chose the temperature and log(g) of our Phoenix stellar templates based on the Padova Isochrones (Marigo et al. 2017) with an age of 10 Gyr, selecting stars along the subgiant, giant, and horizontal branch because these are expected to dominate the light of GCs. We selected templates with metallicities ranging from [Fe/H] = 0.0 to [Fe/H] = −2.0 with an interval of 0.5 dex, and log(g) from 0 to 4 with an interval of 0.5 dex. The temperature of the templates ranges from 3200–11,200 K. We note that we are not assuming a 10 Gyr age for our templates, but rather use a 10 Gyr isochrone to select the approximate log(g), metallicity, and temperature of the appropriate Phoenix templates because these properties determine the shape of the spectral lines of the templates. This resulted in a library of 46 total stellar templates.

## 3.2. Line-spread Function Determination

The synthetic stellar templates need to be convolved with the intrinsic line-spread function (LSF) of the observed spectra before fitting. We derive the LSF by fitting individual stars observed in each setup with our Phoenix templates using pPXF. We observed stars of known spectral type during the observing runs with MIKE, and those are used to determine the LSF. For M2FS, we did not observe stars of known spectral type, but many of our luminous candidate GCs were found to be Milky Way foreground stars based on their radial velocities ($V<250 \text{ km s}^{-1}$). Assuming the spectrographs have Gaussian LSFs, the derived velocity dispersion for the stars measures the width of the intrinsic LSF of the instrument. The measured dispersion can be converted into FWHM (in Angstroms) $\text{FWHM} = 2\sqrt{2\ln(2)}\sigma_{\text{star}}\lambda_{c}/c$; with $\sigma_{\text{star}}$ being the derived velocity dispersion, c the speed of light, and $\lambda_{c}$ the central wavelength in each order. We used the median FWHM for all

the stars with S/N higher than 20 as the LSF (see Figure A1 in the Appendix). We obtained a different LSF for each filter (Calcium Triplet and Magnesium Triplet) and instrument. The error of the LSF was estimated by taking the standard deviation of the FWHM values, and this was propagated into the dispersion measurements later. The velocity dispersions measured in our luminous GC candidates are much higher than the width of the Gaussian LSF; therefore, the uncertainty in the LSF and errors caused by any non-Gaussianity of the LSF do not significantly affect our results.

## 3.3. Spectral Fitting

To ensure that our GCs are well fit by our selected templates, we optimized our pPXF parameters and template selection to maximize consistency with the velocity dispersion measurements of the 14 massive GCs from Martini & Ho (2004). Specifically, we removed two of our initial templates and set pPXF’s multiplicative polynomial degree to 12. No additive polynomial was used to preserve relative line depths. Our pPXF fits were sensitive to the initial radial velocity guess, with objects with bad initial guesses often resulting in bad fits with unrealistically large dispersions. The initial radial velocity guess was obtained for each luminous GC candidate by running a grid of different radial velocity guesses from 0–900 km s⁻¹ spaced by 100 km s⁻¹, and keeping the results from the fit with the best reduced $\chi^2$. Once a radial velocity guess was obtained, a bad-pixel mask was created by performing a $2\sigma$ clipping to remove outliers.

Because no sky subtraction was done during the data reduction for the M2FS data, for the Calcium Triplet M2FS data, we fit the sky emission lines with spectra from dedicated sky fibers in our field of view. After an initial fit, we examined the residuals at the wavelengths of known sky lines (Hanuschik 2003), and masked any pixels where the sky subtraction left significant residuals. For the MIKE data, sky subtraction along the slit was done during the data reduction; this also left behind sky residuals in some cases, and thus we apply the same masking procedure to the Calcium Triplet MIKE data. Our final radial velocity and velocity dispersion measurement pPXF runs use these initial radial velocity guesses and bad-pixel masks as input. An example of the fits for each setup is shown in Figure 3.

To estimate our errors on the radial velocity and dispersion measurements, we first recalculated the radial velocity and velocity dispersion using the lower and upper LSF values (see Figure A1), and then performed Monte Carlo simulations based on the error spectra for each object. Specifically, we added noise to the observed spectrum in every iteration based on its error spectrum and refit in pPXF. This was repeated 50 times for each object.

Figure 4 summarizes the radial velocity and velocity dispersion measurements for the 165 luminous GC candidates with measurable velocity dispersions. Based on previous spectroscopic studies (e.g Peng et al. 2004), we use a radial velocity cut of 250 km s⁻¹ to separate Cen A objects from possible foreground objects. Most targets with radial velocities lower than 250 km s⁻¹ have significant ($>2\sigma$) Gaia EDR3 proper motions, and thus they are consistent with being Milky Way foreground stars. The target with radial velocity $\sim230 \text{ km s}^{-1}$ (H12_82) has a significant Gaia EDR3 proper motion, suggesting it is a foreground star. High-velocity dispersion foreground objects are most likely binary stars;
<figure><img src="image_7.png" /><figcaption>**Figure 3.** Spectral fit using pPXF examples for three luminous GCs in the M2FS Magnesium Triplet (M2FS Mg) (a), M2FS Calcium Triplet (M2FS Ca) (b), and MIKE Calcium Triplet (MIKE Ca) (c). The y-axis represents the relative flux per unit of wavelength. The observed spectrum (black) is fitted using the combination of stellar models (red). Gray vertical lines show masked regions including sky emission lines.</figcaption></figure>

visual inspection shows double lines in many cases. None of the Cen A objects showed similar double line profiles.

### 3.4. Comparison to Literature and Reliability Assessment

Seventy of our luminous GC targets have literature radial velocity measurements (Peng et al. 2004; Woodley et al. 2005; Rejkuba et al. 2007; Beasley et al. 2008; Woodley et al. 2010). Out of these 70 targets, 13 have available velocity dispersions. Figure 5 shows the comparison of radial velocity measurements with literature values. We find a good agreement between the two with a scatter of 20 km s⁻¹ and minimal bias. This scatter is in excess of reported velocity measurements in many cases. However, we think that this is a result of errors being underestimated in previous work; Beasley et al. (2008) found a 35 km s⁻¹ offset and 60 km s⁻¹ scatter in comparing their work to that of Peng et al. (2004). We reclassify four targets as foreground stars that were previously classified as Cen A GCs based on their radial velocities: these include two targets (HH-32 and AAT112964) from Beasley et al. (2008) and one object from (T17-1974) Taylor et al. (2015).<fnref n="10" />

For the 13 luminous GCs with previous velocity dispersion measurements from Rejkuba et al. (2007), we can determine the velocity dispersion for nine of them. Their comparison with literature values is shown in Figure 6. The velocity dispersions of the 14 luminous GCs from Martini & Ho (2004) used to set up our pPXF fits (see Section 3.3) are shown in gray in Figure 6 because they are not part of the new measurements of luminous GCs presented here. We find a very good agreement with literature values, with a standard deviation of the residuals of 2 km s⁻¹, which is consistent with our velocity dispersion uncertainties. We do not include the S/N < 5 velocity dispersion measurements for T17-1974 in Taylor et al. (2015), which was found to have a Milky Way foreground velocity.

The reliability of our dispersion measurements clearly correlates with S/N. However, due to varying positions of sky lines and outlier pixels in the spectra, a simple S/N cut did not cleanly separate good and bad measurements. For that reason, we visually inspected the shape and depth of multiple absorption lines in the fit for each luminous GC candidate to

determine if the fit was reliable; the kinematic fits passing this inspection are hereafter referred to as “visually verified” measurements. Figure 2 shows that our final visually verified dispersions are clearly correlated with S/N, with most spectra above S/N of 10 providing reliable dispersion measurements. We also find that almost all clusters with visually verified dispersions have $g_0 \lesssim 19$.

### 3.5. Repeated Measurements and Uncertainties

Many targets were observed with multiple setups (M2FS Magnesium Triplet and Calcium Triplet), or both with M2FS and MIKE. This allows us to do a comparison of their radial velocity and velocity dispersion to test any possible instrumental bias or differences between the Calcium Triplet and Magnesium Triplet measurements. The radial velocity comparison for 23 luminous GCs observed in both the Magnesium Triplet and Calcium Triplet is shown in Figure 7. We also included the 14 luminous GCs from Martini & Ho (2004) (see Section 3.3 for more details). For the Calcium Triplet radial velocities, we found a systematic offset toward higher values relative to Magnesium Triplet radial velocities. This systematic offset was 5.91 and 2.41 km s⁻¹ for objects observed with M2FS and MIKE respectively; because we have no way of knowing which velocity is correct, we add these offsets as errors in quadrature with the Monte Carlo radial velocity errors for the two instruments.

In comparing repeat measurements, we found that our Monte Carlo errors for our velocity dispersion (see Section 3.3) were significantly underestimated. We therefore rescaled our errors based on these repeated measurements by fitting a Gaussian distribution to the difference of our repeated measurements normalized by their errors ((σ<sub>Mg</sub> − σ<sub>Ca</sub>)/√(error<sub>σMg</sub>² + error<sub>σCa</sub>²)). This gives us a scaling factor of 3.26 that we apply to all our velocity dispersion errors such that the repeated measurement differences normalized by the errors have a standard deviation of 1.

Three luminous GCs were observed with both M2FS and MIKE: H12_78, KV19-271, and pff_gc-098. These are shown in cyan in Figures 7 and 8—the x-axis position shows their MIKE calcium Triplet measurements. On the y-axis, for KV19-271, the Magnesium Triplet and Calcium Triplet M2FS observations are plotted separately, while for H12_78 we use the M2FS Calcium Triplet value.

<footnote n="10">¹⁰ The previous velocities for these objects are 480 ± 27.4 for HH-32, 439 ± 97.9 km s⁻¹ for AAT112964, and 503 ± 8 km s⁻¹ for T17-1974; our derived velocities are listed in Table 2.</footnote>
<figure><img src="image_8.png" /><figcaption>**Figure 4.** Left: radial velocity versus velocity dispersion for 165 luminous GC candidates with measurable dispersions. The black vertical dashed line shows the minimum radial velocity for Cen A GCs (250 km s⁻¹). Gray symbols show likely binary stars. Right: relation between *g* mag and velocity dispersion for the 57 luminous GCs with visually verified velocity dispersion. We expect a relation between these two quantities assuming that mass follows light, with brighter GC being more massive, and a *g* mag = 18.7 corresponds roughly to a luminous GC mass of 10⁶M☉ assuming a mass-to-light ratio of 2.</figcaption></figure>

<figure><img src="image_9.png" /><figcaption>**Figure 5.** Comparison of 41 radial velocities in common between this work and values from the literature (Peng et al. 2004; Woodley et al. 2005; Rejkuba et al. 2007; Beasley et al. 2008; Woodley et al. 2010). The solid black line shows the one-to-one relation. Symbols represent the different configurations as described in Figure 4. The standard deviation of the residuals is 20 km s⁻¹.</figcaption></figure>

<figure><img src="image_10.png" /><figcaption>**Figure 6.** Comparison of 14 velocity dispersion estimates in common between this work and literature values from Harris et al. (2002), Martini & Ho (2004), Rejkuba et al. (2007), Taylor et al. (2010), and Taylor et al. (2015). The MH2004 MIKE data show the comparison with our analysis of the Martini & Ho (2004) data compared with their published values. The standard deviation of the residuals is 2 km s⁻¹.</figcaption></figure>

Figure 8 shows the velocity dispersion comparison for the same 37 luminous GCs from Figure 7 observed in both the Magnesium Triplet and Calcium Triplet. We find a good agreement between the Magnesium Triplets' and Calcium Triplets' velocity dispersions, with a scatter of ~2 km s⁻¹.

### 3.6. Metallicities

Using the weights of the templates used in the best fit from pPXF, we obtained a luminosity-weighted estimate of the metallicity of our luminous GC sample. The use of individual star templates (rather than Simple Stellar Population templates)

and the known Age-Metallicity degeneracy for stars may lead to systematic uncertainties of the metallicity in some cases. For luminous GCs observed with MIKE where derived metallicities are available in the Calcium Triplet and also in the Magnesium Triplet (centered at 5127–5277 Å), we present the error-weighted average metallicity between the two measurements.

To test the robustness of our metallicity estimates, we examine how they correlate with the measured colors from the NOAO photometry (Section 2.1), as well as metallicities for 31 of our luminous GCs inferred from Washington C − T₁ photometry from Harris et al. (2004). All 31 of these are
<figure><img src="image_11.png" /><figcaption>**Figure 7.** Comparison of 37 radial velocities for luminous GCs observed both in the Calcium Triplet and Magnesium Triplet. The red diamond and green inverse pyramids indicate GCs observed in both orders with M2FS and MIKE respectively. The MH2004 symbols indicate our rereduction of the MIKE data from Martini & Ho (2004), while the Cyan symbols indicate cross-instrument comparisons detailed in the text.</figcaption></figure>

M2FS objects. These comparisons are shown in Figure 9. In the left panel we see the luminous GCs fall along the expected sequence, with lower metallicity objects being bluer, while higher metallicity are redder. In the right panel, the Harris et al. (2004) metallicity estimates are well correlated with our estimated metallicities—they have a Spearman coefficient of $r_{spearman} = 0.56$, suggesting that the correlation has a >99% significance, and a scatter of 0.32 dex. We have added this scatter in quadrature to the Monte Carlo errors in metallicity; these are the error bars shown in the right panel and listed in Table 2.

*Outliers:* In the right panel, we see two clusters lying at $(u - r)_0 \sim 2.4$ that fall far below the GC sequence and that have colors similar to foreground stars. Both objects (K-029 and HGHH-19) have radial velocities consistent with being Cen A GCs ($638.8 \pm 5.9$ km s⁻¹ and 621.7 ± 5.9 km s⁻¹ respectively), and no significant Gaia EDR3 proper motions ($\lesssim 0.8$ mas yr⁻¹). On the right panel, the largest outliers on the bottom right and top left (T17-2078 and HH-10) are both located near the center of Cen A, and both show close companions that contaminate their photometry or spectroscopic measurement and compromise the derived metallicity. Based on these outliers, and the large scatter found in the right panel of Figure 9, we suggest caution in any future use of individual GC metallicities published here.

## 4. Radii and Luminosity Determination

In this section we discuss how we derived structural parameters and determine V-band luminosities for our sample of 57 luminous GCs with visually verified velocity dispersions. Structural parameters, in particular half-mass radii, are needed to derive virial masses. We then use the virial masses combined with V-band luminosities to estimate their mass-to-light ratios, which is the primary scientific goal of this work.

<figure><img src="image_12.png" /><figcaption>**Figure 8.** Comparison of 37 velocity dispersion measurements for luminous GCs observed in both the Calcium Triplet and Magnesium Triplet. Symbols are as described in Figure 7.</figcaption></figure>

### 4.1. Radii Determination

Generally, half-mass radii are determined from the modeling of the light profile of imaging data, such as King models (King 1962, 1966) hereafter King62 and King66 respectively. At the distance of Cen A the typical GC half-light radius of 3 pc corresponds to just 0.′′16; thus high-resolution imaging is needed to estimate their sizes. Unfortunately, there is only archival high-resolution Hubble Space Telescope (HST) imaging data for 12 of our luminous GC candidates. We also have ground-based PISCeS imaging at the 6.5 m telescope Magellan Clay (Crnojević et al. 2016); although these data were taken in good seeing conditions (~0.′′65), they do not resolve the GC sizes, and modeling of the sizes from point-spread function (PSF) convolved-fits results in large errors in the inferred sizes.

For that reason, to determine the physical sizes of our GC candidates, we revisited the relation found in Voggel et al. (2020) between HST-based luminous GC sizes and the BP-RP Gaia excess factor (hereafter BR<sub>excess</sub>). The BR<sub>excess</sub> is the ratio of the combined fluxes of the Blue-Pass (BP, 3300–6800 Å) and Red-Pass (RP, 6400–10500 Å) calculated in a window of 3.′′5 × 2.′′1, with the G-band flux determined from PSF fitting. (Gaia EDR3 has an effective angular resolution of ~0.′′4; Fabricius et al. 2021.) The BR<sub>excess</sub> is sensitive to extended objects because the BP and RP are calculated over a larger area than the PSF photometry of the G-band. The BR<sub>excess</sub> is ~1 for point sources and larger for extended sources. We decided to use the newly available Gaia EDR3 catalog, instead of Gaia DR2 used in Voggel et al. (2020). Gaia EDR3 is more complete and thus has more sources with existing HST measurements for comparison. Additionally, the BR<sub>excess</sub> has also been recalibrated in Gaia EDR3 (Riello et al. 2021) relative to the Gaia DR2 values presented in Voggel et al. (2020); we also use half-mass radii here in place of half-light radii used in Voggel et al. (2020) to provide the inputs needed for virial masses.

To determine the relation between half-mass radius and BR<sub>excess</sub>, we compiled a list of 71 half-light radii ($r_h$) and concentrations ($c = r_t/r_c$, with $r_t$ and $r_c$ being the tidal and core radii) of luminous GCs in Cen A derived from King66 model
<figure><img src="image_13.png" /><figcaption>**Figure 9.** Left: r-z vs. u-r color plot for luminous GCs and Milky Way foreground stars colored by luminosity-weighted metallicities estimate. The triangles, pentagons, and squares represent targets observed with M2FS Magnesium Triplet, M2FS Calcium Triplet, and MIKE, respectively. Right: comparison of our flux weighted metallicities (x-axis) to derived metallicities (y-axis) for 31 luminous GCs using color information from the Washington photometric system from Harris et al. (2004). Symbols are as described above. The dashed black line shows the one-to-one comparison.</figcaption></figure>

fits to HST images from McLaughlin et al. (2008). To convert their half-light radii to half-mass radii, we integrated King66 models for a range of concentrations to obtain the following relation:

$$r_{\text{hm}} = r_h(1.33592 - 0.05677 \log(c) + 0.03942 \log(c)^2 + 0.01146 \log(c)^3 - 0.00622 \log(c)^4) \quad (1)$$

The left panel in Figure 10 shows the resulting half-mass radii versus the measured Gaia BR<sub>excess</sub> colored by Gaia G magnitude. These two quantities show a strong positive correlation with a Spearman coefficient r<sub>spearman</sub> = 0.81, suggesting that the correlation has a >99.9% significance.

We find a better recovery of the half-mass radii when including also a G-band magnitude dependence in the relation between half-mass radii and BR<sub>excess</sub>. The resulting relation is shown in Equation (2).

$$r_{\text{hm}}'' = (0.08385 - 0.0086(G - 18))(\text{BR}_{\text{excess}} - 2.5) - 0.00785(G - 18) + 0.16135 \quad (2)$$

The right panel in Figure 10 shows the predicted half-mass radii for the sample of literature GCs. We find a fractional scatter of 14%, which is superior to the quality of ground-based sizes as well as the relation found in Voggel et al. (2020).

In this work we use half-mass radii from King66 fit to HST data when available (McLaughlin et al. 2008; Georgiev et al. 2009), and sizes from Gaia EDR3 from Equation (2) otherwise to calculate the mass-to-light ratios for our 57 luminous GCs. In addition three luminous GCs—*Fluffy*, VHH81-5, and VHH81-01—as well as galaxy nuclei ESO269-06 were not in Gaia EDR3. For both VHH81-5 and ESO269-06, HST ACS F606W imaging was available, and we fit King62 profiles (which are analytical) to determine half-mass radii and concentrations using a custom IDL routine that includes PSF convolution (as in Seth 2010). For *Fluffy*, due to its large size and resolution into individual stars, we created a 1D surface brightness profile from the HST WFC3 F606W, and fit this to a King62 model; this work will be presented in more detail in D. Crnojevic et al. (2022, in preparation). We demonstrate in

Section 5.2 that the differences between King62 and King66 profiles are negligible for the purposes of determining dynamical masses. Finally, for VHH81-01, no HST data was available; however, due to its large size, it was easily resolved in our ground-based PISCeS imaging. Using the r-band image, we fit the cluster with PSF convolution to a King66 model using ishape (Larsen 1999); the seeing of the r-band data was 0.15, significantly smaller than the ~1.3 half-light radius (See more details in Section 5.4).

## 4.2. V-band Luminosities

To make our mass-to-light ratios comparable to previous work, we derived V-band mass-to-light ratios. This required that we transform our extinction corrected NOAO Source Catalog DR2 aperture photometry (see Section 2.1) in u, g, r, and z into V-band using the photometric transformation: V = g - 0.59(g - r) - 0.01 from Jester et al. (2005). We compared the derived V-band magnitudes with previous V-band magnitudes for 185 GCs in Cen A from Peng et al. (2004) and Rejkuba (2001), and saw a slight bias of 0.087 mag toward brighter magnitudes in the NOAO DR2 photometry; this offset was constant with magnitude. Comparisons between Rejkuba (2001) and Peng et al. (2004) photometry suggest they are consistent; thus the offset appears to be related to a photometric calibration or aperture correction issue with the NOAO DR2 catalog. We note that available PISCeS photometry is saturated for many of our targets. We therefore use the derived V-band magnitudes derived from NOAO DR2 and subtract 0.087 mag to correct for this bias. For 10 objects we used HST imaging to obtain V-band magnitudes; these are detailed in Appendix.

For all 57 clusters, we calculated the V-band luminosities using $L_V = 10^{-0.4*(V-(m-M)_V-A_V-M_{V,\odot})}$; we assumed $M_{V,\odot} = 4.81$ and $(m-M)_V = 27.91$ (i.e., distance of 3.8 Mpc) from Harris et al. (2010), and $A_V$ was calculated using Schlafly & Finkbeiner (2011) for each object individually. The absolute V-band magnitudes $M_V$ and $E(B-V)$ values used are listed in Table 3.
<table><caption>Table 2
List of All Observed Luminous GCs Candidates</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>GC_cand_37</td><td>This Work</td><td>200.926244</td><td>-43.565931</td><td>8.08</td><td>19.56</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_38</td><td>This Work</td><td>200.959920</td><td>-43.543763</td><td>4.68</td><td>21.04</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>T17-1027</td><td>Taylor2017</td><td>200.969649</td><td>-43.318745</td><td>4.91</td><td>20.01</td><td>502.0</td><td>7.1</td><td>-0.20</td><td>0.34</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>AAT301956</td><td>Beasley2008</td><td>200.977085</td><td>-43.333630</td><td>5.54</td><td>20.37</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-200841</td><td>This Work</td><td>200.979670</td><td>-43.463985</td><td>7.23</td><td>20.51</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_0</td><td>This Work</td><td>200.989659</td><td>-42.868971</td><td>18.46</td><td>18.79</td><td>0.7</td><td>5.9</td><td>-1.03</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>AAT101931</td><td>Beasley2008</td><td>200.993959</td><td>-42.954726</td><td>13.16</td><td>19.84</td><td>337.1</td><td>6.1</td><td>-1.31</td><td>0.36</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>AAT102120</td><td>Beasley2008</td><td>200.998330</td><td>-42.922039</td><td>14.77</td><td>19.88</td><td>254.4</td><td>5.9</td><td>-1.49</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>RV</td></tr><tr><td>AAT103195</td><td>Beasley2008</td><td>201.003257</td><td>-42.993677</td><td>11.31</td><td>20.89</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>AAT103195</td><td>Beasley2008</td><td>201.024791</td><td>-43.065223</td><td>14.64</td><td>20.27</td><td>244.9</td><td>5.9</td><td>-0.15</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>RV</td></tr><tr><td>AAT304867</td><td>Beasley2008</td><td>201.035856</td><td>-43.274220</td><td>10.10</td><td>20.17</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HH-131</td><td>Harris2004</td><td>201.065690</td><td>-42.886768</td><td>14.83</td><td>20.37</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-235</td><td>Voggel2020</td><td>201.068541</td><td>-43.587734</td><td>29.73</td><td>17.44</td><td>-28.8</td><td>5.9</td><td>-0.57</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>H12_322</td><td>Harris2012</td><td>201.073228</td><td>-43.444351</td><td>9.79</td><td>20.38</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HHH86-28</td><td>Hesser1986</td><td>201.075206</td><td>-42.816956</td><td>23.37</td><td>18.45</td><td>468.1</td><td>6.0</td><td>-0.82</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-236</td><td>Voggel2020</td><td>201.076356</td><td>-43.344684</td><td>26.02</td><td>17.94</td><td>-24.2</td><td>6.0</td><td>-0.32</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr><tr><td>KV19-237</td><td>Voggel2020</td><td>201.079546</td><td>-43.125361</td><td>16.37</td><td>19.14</td><td>26.0</td><td>6.0</td><td>-0.16</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>HH-22</td><td>Harris2004</td><td>201.089178</td><td>-43.043633</td><td>30.51</td><td>18.04</td><td>615.2</td><td>5.9</td><td>-0.36</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>HH-99</td><td>Harris2004</td><td>201.099886</td><td>-42.902972</td><td>14.11</td><td>19.61</td><td>614.8</td><td>6.0</td><td>-1.47</td><td>0.34</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-239</td><td>Voggel2020</td><td>201.103008</td><td>-43.443754</td><td>33.39</td><td>18.00</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC0025</td><td>Woodley2007</td><td>201.106419</td><td>-43.359877</td><td>12.76</td><td>19.36</td><td>797.2</td><td>5.9</td><td>-0.57</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>H21-212899</td><td>This Work</td><td>201.106504</td><td>-43.553764</td><td>21.39</td><td>20.86</td><td>54.1</td><td>5.9</td><td>-0.57</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_7</td><td>This Work</td><td>201.136470</td><td>-42.817503</td><td>12.11</td><td>...</td><td>17.8</td><td>5.9</td><td>-1.01</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_9</td><td>This Work</td><td>201.141940</td><td>-42.890835</td><td>11.63</td><td>20.41</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_40</td><td>This Work</td><td>201.144070</td><td>-43.461493</td><td>10.22</td><td>20.66</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_45</td><td>This Work</td><td>201.154846</td><td>-43.280524</td><td>8.77</td><td>20.36</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_8</td><td>This Work</td><td>201.156854</td><td>-42.885295</td><td>12.82</td><td>20.13</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-217713</td><td>This Work</td><td>201.158430</td><td>-43.607932</td><td>12.01</td><td>19.21</td><td>-1.2</td><td>6.0</td><td>-0.85</td><td>0.35</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_1</td><td>This Work</td><td>201.166150</td><td>-43.134317</td><td>10.41</td><td>21.46</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_39</td><td>This Work</td><td>201.166752</td><td>-43.465841</td><td>3.33</td><td>20.64</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-218792</td><td>This Work</td><td>201.170680</td><td>-42.870212</td><td>13.63</td><td>20.54</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-248</td><td>Voggel2020</td><td>201.174218</td><td>-42.816574</td><td>48.13</td><td>17.90</td><td>13.4</td><td>5.9</td><td>-0.17</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>GC_cand_42</td><td>This Work</td><td>201.179490</td><td>-43.247139</td><td>6.78</td><td>20.67</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HH-143</td><td>Harris2004_new</td><td>201.184850</td><td>-42.952465</td><td>14.33</td><td>19.98</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-250</td><td>Voggel2020</td><td>201.188688</td><td>-43.666411</td><td>18.18</td><td>18.24</td><td>-146.2</td><td>16.0</td><td>-1.89</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>E</td></tr><tr><td>HHH86-10</td><td>Hesser1986</td><td>201.200123</td><td>-43.137294</td><td>6.55</td><td>18.47</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>T17-1253</td><td>Taylor2017</td><td>201.204815</td><td>-43.086707</td><td>17.83</td><td>19.63</td><td>548.3</td><td>5.9</td><td>-0.19</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>GC_cand_10</td><td>This Work</td><td>201.206403</td><td>-42.922385</td><td>14.84</td><td>22.57</td><td>26.1</td><td>6.0</td><td>-1.33</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>H21-222371</td><td>This Work</td><td>201.209112</td><td>-43.167224</td><td>12.03</td><td>20.50</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-222450</td><td>This Work</td><td>201.209890</td><td>-43.700870</td><td>6.12</td><td>19.97</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_3</td><td>This Work</td><td>201.210790</td><td>-43.055253</td><td>11.22</td><td>19.26</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_4</td><td>This Work</td><td>201.222380</td><td>-43.051019</td><td>14.16</td><td>17.46</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>AAT111185</td><td>Beasley2008</td><td>201.224886</td><td>-43.073512</td><td>14.18</td><td>20.00</td><td>297.6</td><td>6.4</td><td>-1.36</td><td>0.34</td><td>M2FS ca</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_2</td><td>This Work</td><td>201.225340</td><td>-43.163812</td><td>9.45</td><td>19.90</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HHH86-30</td><td>Hesser1986</td><td>201.226440</td><td>-42.890201</td><td>52.10</td><td>17.26</td><td>780.2</td><td>5.9</td><td>-0.01</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC0450</td><td>Woodley2010</td><td>201.229040</td><td>-43.047889</td><td>10.77</td><td>20.35</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_320</td><td>Harris2012</td><td>201.236101</td><td>-43.091498</td><td>12.91</td><td>20.15</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_5</td><td>This Work</td><td>201.240711</td><td>-42.875204</td><td>15.94</td><td>20.52</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>KV19-262</td><td>Voggel2020</td><td>201.242945</td><td>-42.990417</td><td>29.11</td><td>18.87</td><td>-5.0</td><td>6.0</td><td>-0.20</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>pff_gc-026</td><td>Peng2004</td><td>201.243514</td><td>-42.714822</td><td>11.58</td><td>19.46</td><td>423.8</td><td>6.2</td><td>-1.25</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>PFF-gc028</td><td>Peng2004</td><td>201.254757</td><td>-42.947666</td><td>25.99</td><td>18.86</td><td>539.6</td><td>5.9</td><td>-0.29</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>HH-146</td><td>Harris2004_new</td><td>201.255640</td><td>-42.997411</td><td>12.57</td><td>19.82</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-265</td><td>Voggel2020</td><td>201.257206</td><td>-43.018565</td><td>47.90</td><td>16.58</td><td>-2.8</td><td>6.0</td><td>-0.24</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr><tr><td>HGHH-G066</td><td>Harris1992</td><td>201.263148</td><td>-43.050712</td><td>29.46</td><td>18.80</td><td>581.4</td><td>5.9</td><td>-0.21</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-268</td><td>Voggel2020</td><td>201.267822</td><td>-43.654668</td><td>4.14</td><td>18.19</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>AAT112964</td><td>Beasley2008</td><td>201.269131</td><td>-43.122756</td><td>15.65</td><td>19.69</td><td>38.3</td><td>6.1</td><td>-1.89</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>RV</td></tr><tr><td>HGHH-43</td><td>Harris1992</td><td>201.269935</td><td>-43.160808</td><td>17.43</td><td>18.65</td><td>497.6</td><td>5.9</td><td>-0.43</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>T17-1388</td><td>Taylor2017</td><td>201.270881</td><td>-42.954239</td><td>...</td><td>17.50</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HGHH-G342</td><td>Harris1992</td><td>201.274196</td><td>-42.983493</td><td>32.27</td><td>18.13</td><td>529.5</td><td>5.9</td><td>-0.26</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-270</td><td>Voggel2020</td><td>201.279400</td><td>-43.589595</td><td>3.77</td><td>16.08</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_362</td><td>Harris2012</td><td>201.280990</td><td>-43.576428</td><td>6.83</td><td>20.25</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-229155</td><td>This Work</td><td>201.284580</td><td>-43.602688</td><td>9.99</td><td>20.65</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>K-029</td><td>Kraft2001</td><td>201.288256</td><td>-42.983105</td><td>22.82</td><td>17.28</td><td>638.8</td><td>5.9</td><td>-0.43</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_41</td><td>This Work</td><td>201.290160</td><td>-43.680682</td><td>7.65</td><td>19.64</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>K-034</td><td>Kraft2001</td><td>201.292745</td><td>-42.892504</td><td>36.00</td><td>17.78</td><td>460.6</td><td>5.9</td><td>-0.20</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>H12_312</td><td>Harris2012</td><td>201.293322</td><td>-43.389607</td><td>9.03</td><td>20.35</td><td>553.3</td><td>5.9</td><td>-0.38</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>HHH86-14</td><td>Hesser1986</td><td>201.293668</td><td>-42.747977</td><td>30.43</td><td>17.88</td><td>699.9</td><td>5.9</td><td>-0.26</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>T17-1444</td><td>Taylor2017</td><td>201.299889</td><td>-42.953690</td><td>20.13</td><td>19.14</td><td>392.8</td><td>5.9</td><td>-0.51</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>H12_321</td><td>Harris2012</td><td>201.300813</td><td>-42.828038</td><td>13.88</td><td>20.37</td><td>422.3</td><td>5.9</td><td>-1.73</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>KV19-273</td><td>Voggel2020</td><td>201.304097</td><td>-42.989558</td><td>27.59</td><td>18.14</td><td>574.4</td><td>5.9</td><td>-0.42</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>C</td></tr><tr><td>GC_cand_6</td><td>This Work</td><td>201.307520</td><td>-42.906243</td><td>16.47</td><td>20.08</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_356</td><td>Harris2012</td><td>201.307530</td><td>-42.891987</td><td>10.81</td><td>21.02</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_11</td><td>This Work</td><td>201.307884</td><td>-43.123905</td><td>13.14</td><td>19.61</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_46</td><td>This Work</td><td>201.316690</td><td>-43.684997</td><td>5.81</td><td>21.11</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HHH86-33</td><td>Hesser1986</td><td>201.317717</td><td>-42.848127</td><td>28.94</td><td>18.53</td><td>526.6</td><td>5.9</td><td>-0.40</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>HGHH-G219</td><td>Harris1992</td><td>201.322045</td><td>-42.979623</td><td>28.59</td><td>16.41</td><td>521.7</td><td>5.9</td><td>-0.30</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>R253</td><td>Rejkuba2001</td><td>201.322105</td><td>-43.144183</td><td>10.29</td><td>19.74</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>T17-1511</td><td>Taylor2017</td><td>201.327091</td><td>-43.021130</td><td>41.86</td><td>16.13</td><td>525.4</td><td>5.9</td><td>-0.26</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_18</td><td>This Work</td><td>201.329656</td><td>-43.152162</td><td>10.54</td><td>21.49</td><td>-47.8</td><td>8.9</td><td>-1.08</td><td>0.37</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_43</td><td>This Work</td><td>201.331820</td><td>-43.267958</td><td>8.27</td><td>20.85</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_17</td><td>This Work</td><td>201.332360</td><td>-42.910364</td><td>11.79</td><td>22.40</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-280</td><td>Voggel2020</td><td>201.334631</td><td>-42.985827</td><td>24.91</td><td>16.22</td><td>492.0</td><td>6.0</td><td>-0.35</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>B</td></tr><tr><td>KV19-281</td><td>Voggel2020</td><td>201.337980</td><td>-43.533540</td><td>17.65</td><td>19.92</td><td>-40.5</td><td>6.0</td><td>-0.14</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr><tr><td>T17-1533</td><td>Taylor2017</td><td>201.339477</td><td>-43.324859</td><td>14.25</td><td>19.00</td><td>328.5</td><td>6.1</td><td>-1.79</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>GC0429</td><td>Woodley2010</td><td>201.345304</td><td>-43.136178</td><td>23.15</td><td>19.19</td><td>38.3</td><td>5.9</td><td>-0.14</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>Sigma</td></tr><tr><td>HH-180</td><td>Harris2004_new</td><td>201.354510</td><td>-43.151349</td><td>9.24</td><td>20.06</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-284</td><td>Voggel2020</td><td>201.357892</td><td>-42.986728</td><td>26.05</td><td>15.15</td><td>-8.7</td><td>5.9</td><td>-2.00</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>KV19-286</td><td>Voggel2020</td><td>201.358467</td><td>-42.972696</td><td>...</td><td>16.51</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_16</td><td>This Work</td><td>201.358769</td><td>-42.851680</td><td>11.43</td><td>20.99</td><td>-71.3</td><td>5.9</td><td>-1.15</td><td>0.37</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>KV19-287</td><td>Voggel2020</td><td>201.368097</td><td>-42.775991</td><td>24.45</td><td>18.00</td><td>187.9</td><td>6.0</td><td>-0.47</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr><tr><td>KV19-288</td><td>Voggel2020</td><td>201.369036</td><td>-42.941958</td><td>30.83</td><td>18.18</td><td>494.3</td><td>5.9</td><td>-0.41</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>A</td></tr><tr><td>WHH-17</td><td>Woodley2005</td><td>201.371848</td><td>-42.963098</td><td>28.44</td><td>18.46</td><td>693.7</td><td>5.9</td><td>-0.45</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>H21-237144</td><td>This Work</td><td>201.373273</td><td>-43.612256</td><td>10.72</td><td>20.50</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>WHH-18</td><td>Woodley2005</td><td>201.375285</td><td>-42.946367</td><td>31.76</td><td>18.50</td><td>790.5</td><td>5.9</td><td>-0.20</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>HH-10</td><td>Harris2004</td><td>201.379309</td><td>-42.837526</td><td>42.67</td><td>17.25</td><td>503.0</td><td>5.9</td><td>-0.20</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-289</td><td>Voggel2020</td><td>201.380317</td><td>-43.046136</td><td>43.11</td><td>14.63</td><td>640.1</td><td>5.9</td><td>-0.21</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>B</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>HGHH-G359</td><td>Harris1992</td><td>201.385034</td><td>-42.980587</td><td>17.31</td><td>15.57</td><td>526.1</td><td>6.0</td><td>-0.63</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>H12_106</td><td>Harris2012</td><td>201.386037</td><td>-43.560646</td><td>21.97</td><td>18.31</td><td>595.8</td><td>5.9</td><td>-0.35</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>A</td></tr><tr><td>PFF-gc056</td><td>Peng2004</td><td>201.386638</td><td>-42.940098</td><td>24.32</td><td>18.67</td><td>280.3</td><td>5.9</td><td>-0.93</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_14</td><td>This Work</td><td>201.386687</td><td>-42.900866</td><td>18.34</td><td>19.54</td><td>101.6</td><td>5.9</td><td>-1.42</td><td>0.34</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_13</td><td>This Work</td><td>201.390917</td><td>-42.832569</td><td>36.32</td><td>17.67</td><td>-19.5</td><td>6.1</td><td>-0.28</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>T17-1637</td><td>Taylor2017</td><td>201.395080</td><td>-42.943318</td><td>12.33</td><td>20.16</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-292</td><td>Voggel2020</td><td>201.396382</td><td>-42.808698</td><td>22.31</td><td>19.45</td><td>1.7</td><td>5.9</td><td>-0.10</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>WHH-22</td><td>Woodley2005</td><td>201.397118</td><td>-43.091414</td><td>26.11</td><td>18.10</td><td>633.9</td><td>5.9</td><td>-0.35</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>T17-1664</td><td>Taylor2017</td><td>201.407702</td><td>-42.941120</td><td>27.23</td><td>19.01</td><td>518.4</td><td>5.9</td><td>-0.23</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>T17-1665</td><td>Taylor2017</td><td>201.408278</td><td>-43.283169</td><td>5.59</td><td>19.92</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-295</td><td>Voggel2020</td><td>201.418464</td><td>-43.047600</td><td>19.89</td><td>19.17</td><td>805.2</td><td>6.0</td><td>-0.45</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>B</td></tr><tr><td>HHH86-34</td><td>Hesser1986</td><td>201.419139</td><td>-43.353852</td><td>22.79</td><td>18.45</td><td>648.5</td><td>5.9</td><td>-0.18</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_48</td><td>This Work</td><td>201.420890</td><td>-43.628902</td><td>...</td><td>19.52</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HGHH-19</td><td>Harris1992</td><td>201.430768</td><td>-43.123036</td><td>22.64</td><td>18.18</td><td>621.7</td><td>5.9</td><td>-0.37</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-296</td><td>Voggel2020</td><td>201.430918</td><td>-43.300956</td><td>32.27</td><td>17.91</td><td>-53.5</td><td>5.9</td><td>-0.12</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>HGHH-35</td><td>Harris1992</td><td>201.434161</td><td>-42.983166</td><td>32.35</td><td>17.91</td><td>595.7</td><td>5.9</td><td>-0.27</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_47</td><td>This Work</td><td>201.436130</td><td>-43.642691</td><td>5.46</td><td>19.45</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>N21</td><td>Gomez2006</td><td>201.437940</td><td>-42.649436</td><td>6.69</td><td>20.21</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>AAT119596</td><td>Beasley2008</td><td>201.441813</td><td>-43.140152</td><td>11.27</td><td>19.85</td><td>625.3</td><td>6.0</td><td>-1.34</td><td>0.35</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_49</td><td>This Work</td><td>201.443400</td><td>-43.604783</td><td>8.18</td><td>22.33</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC0590</td><td>Woodley2010</td><td>201.445670</td><td>-42.876120</td><td>4.83</td><td>19.91</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HGHH-G204</td><td>Harris1992</td><td>201.445728</td><td>-43.034851</td><td>27.90</td><td>18.33</td><td>737.7</td><td>5.9</td><td>-0.74</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>HGHH-G251</td><td>Harris1992</td><td>201.452204</td><td>-42.961431</td><td>25.81</td><td>19.06</td><td>624.5</td><td>5.9</td><td>-0.26</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_44</td><td>This Work</td><td>201.453510</td><td>-43.368077</td><td>10.65</td><td>21.30</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-300</td><td>Voggel2020</td><td>201.461884</td><td>-42.950591</td><td>42.84</td><td>17.19</td><td>-57.7</td><td>5.9</td><td>-0.29</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>GC_cand_21</td><td>This Work</td><td>201.469270</td><td>-43.083283</td><td>9.42</td><td>21.57</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_50</td><td>This Work</td><td>201.471130</td><td>-43.541966</td><td>10.73</td><td>21.16</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC0323</td><td>Woodley2007</td><td>201.472030</td><td>-42.514632</td><td>5.99</td><td>20.34</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_22</td><td>This Work</td><td>201.474470</td><td>-42.995220</td><td>12.67</td><td>19.74</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_23</td><td>This Work</td><td>201.477750</td><td>-43.131096</td><td>8.03</td><td>21.39</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_310</td><td>Harris2012</td><td>201.478079</td><td>-42.712559</td><td>4.02</td><td>20.26</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HH-107</td><td>Harris2004_new</td><td>201.485960</td><td>-42.979333</td><td>13.14</td><td>19.59</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-247341</td><td>This Work</td><td>201.486674</td><td>-42.499387</td><td>10.12</td><td>20.68</td><td>-45.7</td><td>5.9</td><td>-0.74</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_15</td><td>This Work</td><td>201.490884</td><td>-42.918465</td><td>15.12</td><td>20.80</td><td>-26.8</td><td>6.5</td><td>-0.70</td><td>0.34</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>pff-gc-080</td><td>Peng2004</td><td>201.498086</td><td>-42.544269</td><td>6.72</td><td>19.94</td><td>584.7</td><td>6.0</td><td>-1.35</td><td>0.40</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_31</td><td>This Work</td><td>201.499810</td><td>-42.475312</td><td>11.33</td><td>19.33</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC0479</td><td>Woodley2010</td><td>201.500000</td><td>-42.999472</td><td>10.21</td><td>21.04</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_12</td><td>This Work</td><td>201.503270</td><td>-42.811023</td><td>11.80</td><td>20.10</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-309</td><td>Voggel2020</td><td>201.519331</td><td>-43.482248</td><td>21.23</td><td>16.82</td><td>15.2</td><td>5.9</td><td>-0.41</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>AAT122794</td><td>Beasley2008</td><td>201.519470</td><td>-42.793086</td><td>3.34</td><td>20.30</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_215</td><td>Harris2012</td><td>201.525480</td><td>-42.629742</td><td>9.12</td><td>18.58</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_327</td><td>Harris2012</td><td>201.526176</td><td>-42.719741</td><td>4.94</td><td>20.27</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-251200</td><td>This Work</td><td>201.527528</td><td>-42.869796</td><td>12.86</td><td>19.74</td><td>42.6</td><td>6.0</td><td>-0.00</td><td>0.34</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_26</td><td>This Work</td><td>201.529580</td><td>-42.652576</td><td>6.04</td><td>20.31</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-251644</td><td>This Work</td><td>201.531996</td><td>-42.880424</td><td>20.63</td><td>19.74</td><td>-37.8</td><td>6.4</td><td>-0.88</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_24</td><td>This Work</td><td>201.532449</td><td>-43.033752</td><td>19.85</td><td>19.70</td><td>-18.1</td><td>6.1</td><td>-0.97</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>H21-252147</td><td>This Work</td><td>201.537507</td><td>-42.527812</td><td>15.96</td><td>19.96</td><td>-1.6</td><td>6.0</td><td>-0.97</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_19</td><td>This Work</td><td>201.540110</td><td>-42.874367</td><td>10.88</td><td>20.97</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-311</td><td>Voggel2020</td><td>201.543341</td><td>-42.521167</td><td>25.75</td><td>17.05</td><td>-50.4</td><td>6.0</td><td>-0.20</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>GC_cand_20</td><td>This Work</td><td>201.545560</td><td>-42.878286</td><td>9.37</td><td>20.05</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-253874</td><td>This Work</td><td>201.555566</td><td>-42.869355</td><td>14.69</td><td>20.82</td><td>-48.1</td><td>6.0</td><td>-0.40</td><td>0.36</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>GC_cand_32</td><td>This Work</td><td>201.556733</td><td>-42.476640</td><td>9.26</td><td>20.23</td><td>-24.8</td><td>5.9</td><td>-2.00</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>H12_301</td><td>Harris2012</td><td>201.557280</td><td>-42.658710</td><td>5.15</td><td>19.92</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_27</td><td>This Work</td><td>201.560110</td><td>-42.826036</td><td>5.76</td><td>20.69</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HHH86-26</td><td>Hesser1986</td><td>201.563543</td><td>-42.808168</td><td>19.80</td><td>18.25</td><td>366.2</td><td>5.9</td><td>-0.10</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>KV19-320</td><td>Voggel2020</td><td>201.580773</td><td>-42.625020</td><td>20.38</td><td>16.60</td><td>7.4</td><td>5.9</td><td>-0.43</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>D</td></tr><tr><td>GC_cand_25</td><td>This Work</td><td>201.584800</td><td>-42.963931</td><td>8.93</td><td>20.04</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>R118</td><td>Rejkuba2001</td><td>201.591612</td><td>-42.907344</td><td>6.85</td><td>19.84</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-257979</td><td>This Work</td><td>201.592922</td><td>-42.966858</td><td>9.42</td><td>20.20</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>C51</td><td>Harris2004</td><td>201.600676</td><td>-42.783526</td><td>6.86</td><td>18.50</td><td>377.6</td><td>6.2</td><td>-0.07</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>f1.GC-1</td><td>Harris2004_conf</td><td>201.609730</td><td>-42.815443</td><td>5.06</td><td>19.86</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_98</td><td>Harris2012</td><td>201.621990</td><td>-42.690375</td><td>11.07</td><td>18.32</td><td>519.6</td><td>5.9</td><td>-0.21</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>A</td></tr><tr><td>H12_300</td><td>Harris2012</td><td>201.626488</td><td>-42.675358</td><td>5.00</td><td>19.85</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>KV19-325</td><td>Voggel2020</td><td>201.626726</td><td>-42.869731</td><td>4.86</td><td>18.28</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_229</td><td>Harris2012</td><td>201.644783</td><td>-42.677839</td><td>3.50</td><td>19.37</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HGHH-27</td><td>Harris1992</td><td>201.658290</td><td>-42.763861</td><td>4.08</td><td>23.42</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_33</td><td>This Work</td><td>201.671910</td><td>-42.798656</td><td>6.31</td><td>20.38</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>HH-100</td><td>Harris2004</td><td>201.710155</td><td>-42.843434</td><td>5.27</td><td>19.94</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_29</td><td>This Work</td><td>201.712211</td><td>-42.493167</td><td>31.13</td><td>18.11</td><td>94.6</td><td>6.0</td><td>-0.39</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>H21-274800</td><td>This Work</td><td>201.743124</td><td>-42.412481</td><td>8.18</td><td>20.97</td><td>-3.2</td><td>6.2</td><td>-0.89</td><td>0.33</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>pffgc-100</td><td>Peng2004</td><td>201.764180</td><td>-42.454757</td><td>25.09</td><td>18.44</td><td>516.6</td><td>6.0</td><td>-0.26</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>RV</td></tr><tr><td>GC_cand_30</td><td>This Work</td><td>201.765180</td><td>-42.609855</td><td>9.66</td><td>20.09</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_28</td><td>This Work</td><td>201.780810</td><td>-42.462194</td><td>10.10</td><td>19.93</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_36</td><td>This Work</td><td>201.783980</td><td>-42.742342</td><td>9.96</td><td>19.18</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_252</td><td>Harris2012</td><td>201.786313</td><td>-42.770891</td><td>8.93</td><td>19.55</td><td>665.5</td><td>6.3</td><td>-0.96</td><td>0.33</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>H21-281846</td><td>This Work</td><td>201.804760</td><td>-42.548015</td><td>13.25</td><td>20.88</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_194</td><td>Harris2012</td><td>201.824886</td><td>-42.494562</td><td>14.21</td><td>19.13</td><td>508.3</td><td>6.0</td><td>-0.35</td><td>0.32</td><td>M2FS ca</td><td>Y</td><td>New</td></tr><tr><td>H21-284161</td><td>This Work</td><td>201.825763</td><td>-42.490269</td><td>33.38</td><td>18.68</td><td>69.8</td><td>157.9</td><td>-0.03</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>KV19-361</td><td>Voggel2020</td><td>201.871665</td><td>-42.796645</td><td>18.20</td><td>15.97</td><td>3.0</td><td>5.9</td><td>-0.28</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>C</td></tr><tr><td>KV19-367</td><td>Voggel2020</td><td>201.886625</td><td>-42.464203</td><td>7.97</td><td>18.13</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-291979</td><td>This Work</td><td>201.897545</td><td>-42.590191</td><td>11.19</td><td>20.49</td><td>3.0</td><td>6.0</td><td>-0.14</td><td>0.32</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>H21-294165</td><td>This Work</td><td>201.916844</td><td>-42.665642</td><td>10.21</td><td>20.21</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_35</td><td>This Work</td><td>201.923990</td><td>-42.763798</td><td>5.62</td><td>20.93</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H12_259</td><td>Harris2012</td><td>201.926042</td><td>-42.546890</td><td>9.47</td><td>19.60</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_34</td><td>This Work</td><td>201.951410</td><td>-42.532064</td><td>1.54</td><td>19.91</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-301067</td><td>This Work</td><td>201.980690</td><td>-42.662425</td><td>6.29</td><td>20.95</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>H21-301709</td><td>This Work</td><td>201.986469</td><td>-42.636172</td><td>6.66</td><td>20.05</td><td>-1.3</td><td>6.1</td><td>-0.43</td><td>0.34</td><td>M2FS ca</td><td>N</td><td>New</td></tr><tr><td>KV19-386</td><td>Voggel2020</td><td>202.039586</td><td>-42.667068</td><td>15.17</td><td>17.87</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS ca</td><td>...</td><td>...</td></tr><tr><td>GC_cand_58</td><td>This Work</td><td>200.705866</td><td>-43.101057</td><td>14.14</td><td>18.12</td><td>-67.5</td><td>5.9</td><td>-0.08</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_59</td><td>This Work</td><td>200.752432</td><td>-43.112764</td><td>3.19</td><td>18.03</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_57</td><td>This Work</td><td>200.771436</td><td>-42.891460</td><td>1.68</td><td>18.03</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_56</td><td>This Work</td><td>200.772643</td><td>-42.836061</td><td>22.04</td><td>17.51</td><td>-26.4</td><td>5.9</td><td>-0.07</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_98</td><td>This Work</td><td>200.780177</td><td>-42.725442</td><td>16.06</td><td>17.50</td><td>-11.9</td><td>5.9</td><td>-0.10</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_97</td><td>This Work</td><td>200.792280</td><td>-42.467880</td><td>7.44</td><td>17.75</td><td>5.3</td><td>6.0</td><td>-0.32</td><td>0.33</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_99</td><td>This Work</td><td>200.793307</td><td>-42.710812</td><td>16.95</td><td>17.32</td><td>-17.1</td><td>5.9</td><td>-0.23</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_103</td><td>This Work</td><td>200.826807</td><td>-42.720283</td><td>23.66</td><td>17.36</td><td>6.2</td><td>5.9</td><td>-0.05</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>GC_cand_104</td><td>This Work</td><td>200.827638</td><td>-42.603832</td><td>26.15</td><td>17.21</td><td>-24.0</td><td>5.9</td><td>-0.75</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_96</td><td>This Work</td><td>200.833672</td><td>-42.470965</td><td>1.33</td><td>17.21</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_102</td><td>This Work</td><td>200.838575</td><td>-42.504426</td><td>22.64</td><td>17.38</td><td>-19.2</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_108</td><td>This Work</td><td>200.855482</td><td>-42.625245</td><td>25.66</td><td>17.33</td><td>-43.3</td><td>5.9</td><td>-0.01</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>T17-0962</td><td>Taylor2017</td><td>200.867583</td><td>-42.795075</td><td>...</td><td>16.76</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_109</td><td>This Work</td><td>200.884594</td><td>-42.606130</td><td>27.94</td><td>17.31</td><td>-37.4</td><td>5.9</td><td>-0.00</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_61</td><td>This Work</td><td>200.887129</td><td>-42.948218</td><td>15.89</td><td>17.89</td><td>-28.1</td><td>5.9</td><td>-0.04</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HH-32</td><td>Harris2004</td><td>200.909655</td><td>-42.773054</td><td>15.85</td><td>18.30</td><td>-16.4</td><td>5.9</td><td>-0.68</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>RV</td></tr><tr><td>GC_cand_101</td><td>This Work</td><td>200.926014</td><td>-42.441631</td><td>23.23</td><td>17.47</td><td>6.7</td><td>5.9</td><td>-0.24</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HGHH-40</td><td>Harris1992</td><td>200.926391</td><td>-43.160493</td><td>11.08</td><td>18.88</td><td>371.8</td><td>5.9</td><td>-1.46</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>RV</td></tr><tr><td>VHH81-01</td><td>Berg1981</td><td>200.934030</td><td>-43.186620</td><td>16.77</td><td>17.42</td><td>640.0</td><td>5.9</td><td>-0.82</td><td>0.33</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_66</td><td>This Work</td><td>201.001818</td><td>-43.039715</td><td>27.59</td><td>17.88</td><td>-2.7</td><td>5.9</td><td>-0.04</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_67</td><td>This Work</td><td>201.009884</td><td>-43.038126</td><td>12.54</td><td>18.57</td><td>-34.3</td><td>5.9</td><td>-1.01</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_114</td><td>This Work</td><td>201.017203</td><td>-42.476733</td><td>21.41</td><td>18.39</td><td>-11.7</td><td>5.9</td><td>-0.67</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_100</td><td>This Work</td><td>201.017322</td><td>-42.425581</td><td>22.95</td><td>17.45</td><td>65.8</td><td>5.9</td><td>-1.25</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_115</td><td>This Work</td><td>201.029323</td><td>-42.478151</td><td>22.18</td><td>17.77</td><td>-6.6</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_106</td><td>This Work</td><td>201.034219</td><td>-42.375900</td><td>21.56</td><td>17.44</td><td>-25.1</td><td>5.9</td><td>-0.66</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_107</td><td>This Work</td><td>201.054692</td><td>-42.454430</td><td>25.20</td><td>17.54</td><td>-13.6</td><td>5.9</td><td>-0.16</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_105</td><td>This Work</td><td>201.061614</td><td>-42.457369</td><td>28.80</td><td>17.63</td><td>-14.4</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_60</td><td>This Work</td><td>201.066234</td><td>-42.978155</td><td>12.01</td><td>17.97</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_68</td><td>This Work</td><td>201.085209</td><td>-43.028346</td><td>11.81</td><td>17.67</td><td>-20.7</td><td>5.9</td><td>-0.33</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_64</td><td>This Work</td><td>201.093532</td><td>-43.937789</td><td>6.77</td><td>18.58</td><td>-10.9</td><td>5.9</td><td>-0.52</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_67</td><td>Harris2012</td><td>201.100143</td><td>-43.386317</td><td>9.85</td><td>17.68</td><td>-36.2</td><td>5.9</td><td>-0.20</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_65</td><td>This Work</td><td>201.106850</td><td>-42.987902</td><td>47.22</td><td>16.15</td><td>-21.9</td><td>5.9</td><td>-0.59</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>C</td></tr><tr><td>GC_cand_113</td><td>This Work</td><td>201.121446</td><td>-42.424813</td><td>21.84</td><td>17.74</td><td>-2.4</td><td>5.9</td><td>-0.00</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_112</td><td>This Work</td><td>201.130572</td><td>-42.397736</td><td>23.89</td><td>17.52</td><td>-4.1</td><td>5.9</td><td>-0.40</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_54</td><td>Harris2012</td><td>201.132246</td><td>-43.385425</td><td>20.40</td><td>17.62</td><td>17.3</td><td>5.9</td><td>-0.00</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_62</td><td>This Work</td><td>201.137483</td><td>-42.891258</td><td>6.30</td><td>18.14</td><td>-43.7</td><td>5.9</td><td>-0.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_38</td><td>Harris2012</td><td>201.145898</td><td>-43.419643</td><td>17.62</td><td>17.16</td><td>-102.6</td><td>5.9</td><td>-0.47</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_63</td><td>This Work</td><td>201.148937</td><td>-42.944297</td><td>21.12</td><td>17.99</td><td>-43.7</td><td>5.9</td><td>-0.32</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_34</td><td>Harris2012</td><td>201.151485</td><td>-43.394451</td><td>22.04</td><td>17.21</td><td>68.6</td><td>5.9</td><td>-0.22</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HGHH-41</td><td>Harris1992</td><td>201.162357</td><td>-43.335133</td><td>12.23</td><td>18.64</td><td>360.0</td><td>5.9</td><td>-0.40</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>H12_64</td><td>Harris2012</td><td>201.162932</td><td>-43.412671</td><td>18.80</td><td>17.67</td><td>9.2</td><td>5.9</td><td>-0.29</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HHH86-29</td><td>Hesser1986</td><td>201.168230</td><td>-43.301482</td><td>12.58</td><td>18.06</td><td>729.2</td><td>5.9</td><td>-0.30</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>H12_50</td><td>Harris2012</td><td>201.168389</td><td>-43.405788</td><td>24.03</td><td>17.58</td><td>4.2</td><td>5.9</td><td>-0.14</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HGHH-11</td><td>Harris1992</td><td>201.227938</td><td>-43.022712</td><td>5.74</td><td>17.88</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>VHH81-03</td><td>Berg1981</td><td>201.242499</td><td>-42.936124</td><td>15.00</td><td>17.65</td><td>558.4</td><td>5.9</td><td>-0.29</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_110</td><td>This Work</td><td>201.246411</td><td>-42.431244</td><td>19.09</td><td>17.55</td><td>50.8</td><td>5.9</td><td>-0.69</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HGHH-12</td><td>Harris1992</td><td>201.273697</td><td>-43.175240</td><td>8.24</td><td>17.96</td><td>441.4</td><td>5.9</td><td>-0.38</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>T17-1412</td><td>Taylor2017</td><td>201.281782</td><td>-43.020912</td><td>15.82</td><td>17.82</td><td>670.2</td><td>5.9</td><td>-0.39</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_111</td><td>This Work</td><td>201.295914</td><td>-42.467668</td><td>22.76</td><td>17.56</td><td>6.4</td><td>5.9</td><td>-0.26</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_51</td><td>This Work</td><td>201.326213</td><td>-43.418236</td><td>18.40</td><td>18.26</td><td>-55.5</td><td>5.9</td><td>-0.25</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_37</td><td>Harris2012</td><td>201.334010</td><td>-43.207306</td><td>24.70</td><td>17.21</td><td>37.8</td><td>5.9</td><td>-0.30</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HGHH-44</td><td>Harris1992</td><td>201.382221</td><td>-43.322982</td><td>12.29</td><td>18.68</td><td>508.3</td><td>5.9</td><td>-1.11</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_52</td><td>This Work</td><td>201.397008</td><td>-43.401533</td><td>14.10</td><td>17.89</td><td>89.1</td><td>5.9</td><td>-1.22</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_95</td><td>Harris2012</td><td>201.500890</td><td>-43.475899</td><td>16.70</td><td>18.17</td><td>902.3</td><td>5.9</td><td>-1.35</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>A</td></tr><tr><td>HGHH-25</td><td>Harris1992</td><td>201.511787</td><td>-42.949167</td><td>2.15</td><td>18.55</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>HGHH-07</td><td>Harris1992</td><td>201.522474</td><td>-42.942327</td><td>7.85</td><td>17.09</td><td>602.7</td><td>6.1</td><td>-0.91</td><td>0.34</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>HHH86-36</td><td>Hesser1986</td><td>201.532145</td><td>-42.866721</td><td>3.99</td><td>18.42</td><td>694.4</td><td>6.3</td><td>-1.26</td><td>0.36</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>HHH86-37</td><td>Hesser1986</td><td>201.544021</td><td>-42.895178</td><td>0.78</td><td>18.56</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>T17-1974</td><td>Taylor2017</td><td>201.566079</td><td>-42.916914</td><td>9.17</td><td>18.07</td><td>86.1</td><td>6.2</td><td>-1.08</td><td>0.33</td><td>M2FS mg</td><td>N</td><td>Sigma</td></tr><tr><td>GC_cand_54</td><td>This Work</td><td>201.584728</td><td>-43.261976</td><td>12.72</td><td>18.35</td><td>22.9</td><td>5.9</td><td>-0.03</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>HHH86-38</td><td>Hesser1986</td><td>201.599020</td><td>-42.900292</td><td>10.41</td><td>18.53</td><td>405.1</td><td>5.9</td><td>-0.69</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>Sigma</td></tr><tr><td>GC_cand_53</td><td>This Work</td><td>201.609501</td><td>-43.229469</td><td>14.49</td><td>18.42</td><td>91.3</td><td>5.9</td><td>-0.29</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_85</td><td>This Work</td><td>201.613929</td><td>-42.851094</td><td>13.84</td><td>18.15</td><td>34.9</td><td>5.9</td><td>-0.20</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_55</td><td>This Work</td><td>201.627922</td><td>-43.467694</td><td>18.70</td><td>17.79</td><td>38.9</td><td>5.9</td><td>-1.09</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_84</td><td>This Work</td><td>201.645428</td><td>-42.845629</td><td>11.03</td><td>18.26</td><td>12.6</td><td>5.9</td><td>-0.25</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>T17-2078</td><td>Taylor2017</td><td>201.674724</td><td>-43.129189</td><td>7.96</td><td>17.55</td><td>228.1</td><td>5.9</td><td>-0.81</td><td>0.33</td><td>M2FS mg</td><td>N</td><td>RV</td></tr><tr><td>GC_cand_82</td><td>This Work</td><td>201.697685</td><td>-42.902040</td><td>20.99</td><td>17.85</td><td>158.5</td><td>5.9</td><td>-1.30</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_42</td><td>Harris2012</td><td>201.713064</td><td>-43.391586</td><td>24.00</td><td>17.35</td><td>55.5</td><td>5.9</td><td>-0.15</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_83</td><td>This Work</td><td>201.747338</td><td>-42.846370</td><td>15.72</td><td>18.05</td><td>-8.1</td><td>5.9</td><td>-0.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_39</td><td>Harris2012</td><td>201.810932</td><td>-43.278301</td><td>30.31</td><td>17.28</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>H12_80</td><td>Harris2012</td><td>201.829811</td><td>-43.283793</td><td>25.22</td><td>18.01</td><td>7.2</td><td>5.9</td><td>-0.11</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_87</td><td>This Work</td><td>201.851621</td><td>-42.999337</td><td>22.54</td><td>17.82</td><td>-0.2</td><td>5.9</td><td>-0.33</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_86</td><td>This Work</td><td>201.897707</td><td>-43.087222</td><td>11.06</td><td>18.27</td><td>-29.5</td><td>5.9</td><td>-0.56</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_88</td><td>This Work</td><td>201.901736</td><td>-43.083001</td><td>8.52</td><td>18.61</td><td>36.0</td><td>5.9</td><td>-1.08</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_70</td><td>This Work</td><td>201.916629</td><td>-43.212664</td><td>18.88</td><td>18.25</td><td>4.0</td><td>5.9</td><td>-0.11</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_69</td><td>This Work</td><td>201.921895</td><td>-43.254038</td><td>14.36</td><td>18.40</td><td>-12.4</td><td>5.9</td><td>-0.08</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_89</td><td>This Work</td><td>201.946089</td><td>-43.067028</td><td>18.23</td><td>17.99</td><td>-46.9</td><td>5.9</td><td>-0.07</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_82</td><td>Harris2012</td><td>201.993013</td><td>-43.443015</td><td>22.66</td><td>17.24</td><td>...</td><td>...</td><td>...</td><td>...</td><td>M2FS mg</td><td>...</td><td>...</td></tr><tr><td>GC_cand_71</td><td>This Work</td><td>202.001586</td><td>-43.322300</td><td>21.94</td><td>18.08</td><td>-15.9</td><td>5.9</td><td>-0.15</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_92</td><td>This Work</td><td>202.014541</td><td>-42.847463</td><td>17.55</td><td>18.02</td><td>10.8</td><td>5.9</td><td>-0.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_90</td><td>This Work</td><td>202.046173</td><td>-42.885030</td><td>12.55</td><td>17.81</td><td>52.7</td><td>5.9</td><td>-0.27</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_93</td><td>This Work</td><td>202.049456</td><td>-43.003961</td><td>13.84</td><td>18.06</td><td>-34.9</td><td>5.9</td><td>-0.08</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_95</td><td>This Work</td><td>202.070384</td><td>-43.001883</td><td>16.16</td><td>18.09</td><td>-25.8</td><td>5.9</td><td>-0.08</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_94</td><td>This Work</td><td>202.070749</td><td>-43.022249</td><td>16.58</td><td>17.85</td><td>25.9</td><td>5.9</td><td>-0.32</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_91</td><td>This Work</td><td>202.073686</td><td>-42.989262</td><td>11.84</td><td>18.12</td><td>105.3</td><td>5.9</td><td>-0.25</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_75</td><td>This Work</td><td>202.083470</td><td>-43.327759</td><td>19.77</td><td>18.37</td><td>-38.1</td><td>5.9</td><td>-0.14</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_74</td><td>This Work</td><td>202.084923</td><td>-43.263532</td><td>14.23</td><td>18.83</td><td>-20.5</td><td>5.9</td><td>-0.69</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_73</td><td>This Work</td><td>202.086062</td><td>-43.247189</td><td>20.71</td><td>18.13</td><td>31.3</td><td>5.9</td><td>-0.22</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_72</td><td>This Work</td><td>202.108435</td><td>-43.134846</td><td>27.46</td><td>17.14</td><td>-4.6</td><td>5.9</td><td>-0.36</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>H12_141</td><td>Harris2012</td><td>202.112521</td><td>-43.267474</td><td>16.53</td><td>18.50</td><td>427.1</td><td>5.9</td><td>-0.91</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>GC_cand_76</td><td>This Work</td><td>202.113796</td><td>-43.583358</td><td>8.47</td><td>17.64</td><td>51.3</td><td>5.9</td><td>-0.43</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_77</td><td>This Work</td><td>202.125409</td><td>-43.300774</td><td>24.76</td><td>18.10</td><td>-55.5</td><td>5.9</td><td>-0.15</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_80</td><td>This Work</td><td>202.147715</td><td>-43.444444</td><td>33.13</td><td>17.60</td><td>104.7</td><td>5.9</td><td>-0.47</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_79</td><td>This Work</td><td>202.151394</td><td>-43.144182</td><td>12.78</td><td>18.54</td><td>0.5</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_78</td><td>This Work</td><td>202.163200</td><td>-43.252491</td><td>19.57</td><td>17.61</td><td>5.8</td><td>5.9</td><td>-0.31</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_81</td><td>107</td><td>202.218800</td><td>-43.538992</td><td>16.66</td><td>17.62</td><td>-17.6</td><td>5.9</td><td>-0.23</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_119</td><td>This Work</td><td>202.425319</td><td>-41.932317</td><td>18.65</td><td>16.74</td><td>36.1</td><td>5.9</td><td>-0.09</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_118</td><td>This Work</td><td>202.448192</td><td>-42.058635</td><td>20.86</td><td>17.64</td><td>54.3</td><td>5.9</td><td>-0.13</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_117</td><td>This Work</td><td>202.465986</td><td>-41.890188</td><td>13.12</td><td>17.70</td><td>96.2</td><td>5.9</td><td>-0.14</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_116</td><td>This Work</td><td>202.514518</td><td>-41.866283</td><td>19.76</td><td>17.89</td><td>-30.2</td><td>5.9</td><td>-0.22</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_121</td><td>This Work</td><td>202.516108</td><td>-42.095004</td><td>25.43</td><td>17.65</td><td>-23.0</td><td>5.9</td><td>-0.11</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_122</td><td>This Work</td><td>202.516587</td><td>-42.020768</td><td>22.58</td><td>17.75</td><td>-65.9</td><td>5.9</td><td>-0.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr></tbody></table>
<table><caption>Table 2
(Continued)</caption><thead><tr><th>ID</th><th>ID Ref</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>S/N</th><th>g<sub>0</sub><br>(mag)</th><th>R.V<br>(km s<sup>-1</sup>)</th><th>R.V err<br>(km s<sup>-1</sup>)</th><th>Metallicity<br>(Fe/H)</th><th>Metallicity err<br>(Fe/H)</th><th>Setup</th><th>Cen A?</th><th>Ref</th></tr></thead><tbody><tr><td>GC_cand_120</td><td>This Work</td><td>202.542261</td><td>-41.827168</td><td>23.31</td><td>17.68</td><td>26.5</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>Dw1 GC1</td><td>Crnojević</td><td>202.542780</td><td>-41.904666</td><td>5.19</td><td>20.48</td><td>266.0</td><td>5.9</td><td>-1.39</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>Dw1 gc3</td><td>Crnojević</td><td>202.550340</td><td>-41.884030</td><td>2.41</td><td>21.20</td><td>261.6</td><td>6.2</td><td>-1.07</td><td>0.34</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>Dw1 NSC</td><td>Crnojević</td><td>202.558373</td><td>-41.892037</td><td>7.87</td><td>19.51</td><td>273.2</td><td>5.9</td><td>-1.71</td><td>0.32</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>GC_cand_124</td><td>This Work</td><td>202.562538</td><td>-41.830811</td><td>19.20</td><td>17.99</td><td>2.5</td><td>5.9</td><td>-0.17</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>Dw1 gc2</td><td>Crnojević</td><td>202.576700</td><td>-41.890874</td><td>4.57</td><td>20.72</td><td>259.6</td><td>5.9</td><td>-1.13</td><td>0.35</td><td>M2FS mg</td><td>Y</td><td>New</td></tr><tr><td>GC_cand_126</td><td>This Work</td><td>202.652907</td><td>-42.018333</td><td>19.88</td><td>17.67</td><td>-13.4</td><td>5.9</td><td>-0.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_123</td><td>This Work</td><td>202.711633</td><td>-41.896283</td><td>23.86</td><td>17.96</td><td>-54.5</td><td>5.9</td><td>-0.13</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_130</td><td>This Work</td><td>202.745810</td><td>-41.946335</td><td>14.58</td><td>18.34</td><td>-22.5</td><td>5.9</td><td>-1.02</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_129</td><td>This Work</td><td>202.753764</td><td>-41.926794</td><td>24.92</td><td>17.87</td><td>-34.3</td><td>5.9</td><td>-0.10</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_127</td><td>This Work</td><td>202.780820</td><td>-41.922054</td><td>28.91</td><td>17.73</td><td>-71.1</td><td>5.9</td><td>-0.07</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_131</td><td>This Work</td><td>202.782970</td><td>-42.008797</td><td>24.00</td><td>17.93</td><td>6.5</td><td>5.9</td><td>-0.13</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_128</td><td>This Work</td><td>202.822320</td><td>-41.997500</td><td>26.89</td><td>17.73</td><td>53.8</td><td>5.9</td><td>-0.06</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_133</td><td>This Work</td><td>202.890194</td><td>-42.035338</td><td>28.24</td><td>17.66</td><td>32.8</td><td>5.9</td><td>-0.39</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>GC_cand_132</td><td>This Work</td><td>202.915151</td><td>-42.053034</td><td>17.53</td><td>18.24</td><td>37.6</td><td>5.9</td><td>-1.03</td><td>0.32</td><td>M2FS mg</td><td>N</td><td>New</td></tr><tr><td>ESO269-06</td><td>This Work</td><td>198.286770</td><td>-44.889356</td><td>24.28</td><td>16.54</td><td>744.0</td><td>2.4</td><td>-1.26</td><td>0.33</td><td>MIKE</td><td>Y</td><td>RV</td></tr><tr><td>KV19-054</td><td>Voggel2020</td><td>199.102140</td><td>-44.554587</td><td>10.35</td><td>18.04</td><td>...</td><td>...</td><td>...</td><td>...</td><td>MIKE</td><td>...</td><td>...</td></tr><tr><td>Fluffy</td><td>Voggel2020</td><td>199.545360</td><td>-44.157251</td><td>10.52</td><td>18.48</td><td>764.3</td><td>2.5</td><td>-1.79</td><td>0.39</td><td>MIKE</td><td>Y</td><td>RV</td></tr><tr><td>KK197-NSC</td><td>Georgiev2009</td><td>200.508563</td><td>-42.535357</td><td>21.61</td><td>18.00</td><td>639.7</td><td>2.4</td><td>-1.16</td><td>0.34</td><td>MIKE</td><td>Y</td><td>Sigma</td></tr><tr><td>KV19-212</td><td>Voggel2020</td><td>200.790847</td><td>-43.874458</td><td>34.85</td><td>17.92</td><td>571.5</td><td>2.4</td><td>-1.03</td><td>0.33</td><td>MIKE</td><td>Y</td><td>A</td></tr><tr><td>KV19-258</td><td>Voggel2020</td><td>201.223936</td><td>-44.931835</td><td>32.12</td><td>16.06</td><td>2.2</td><td>3.3</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>C</td></tr><tr><td>KV19-271</td><td>Voggel2020</td><td>201.296298</td><td>-43.509212</td><td>9.49</td><td>17.90</td><td>548.3</td><td>2.4</td><td>-0.42</td><td>0.32</td><td>MIKE</td><td>Y</td><td>A</td></tr><tr><td>VHH81-5</td><td>Berg1981</td><td>201.317123</td><td>-42.882801</td><td>33.26</td><td>17.51</td><td>563.2</td><td>2.4</td><td>-1.38</td><td>0.32</td><td>MIKE</td><td>Y</td><td>Sigma</td></tr><tr><td>aat329848</td><td>Beasley2008</td><td>201.505241</td><td>-43.570995</td><td>21.05</td><td>18.26</td><td>552.0</td><td>2.4</td><td>-0.55</td><td>0.33</td><td>MIKE</td><td>Y</td><td>RV</td></tr><tr><td>H12_78</td><td>Harris2012</td><td>201.672201</td><td>-42.703936</td><td>6.50</td><td>17.99</td><td>657.3</td><td>2.4</td><td>-0.71</td><td>0.34</td><td>MIKE</td><td>Y</td><td>A</td></tr><tr><td>pff gc-098</td><td>Peng2004</td><td>201.724630</td><td>-43.321592</td><td>25.70</td><td>18.34</td><td>609.9</td><td>2.4</td><td>-0.50</td><td>0.32</td><td>MIKE</td><td>Y</td><td>RV</td></tr><tr><td>KV19-397</td><td>Voggel2020</td><td>202.104797</td><td>-42.858302</td><td>22.93</td><td>16.52</td><td>-47.9</td><td>3.3</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>D</td></tr><tr><td>KV19-424</td><td>Voggel2020</td><td>202.321726</td><td>-45.212909</td><td>52.44</td><td>15.30</td><td>-62.0</td><td>3.3</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>E</td></tr><tr><td>KV19-442</td><td>Voggel2020</td><td>202.432394</td><td>-42.391404</td><td>6.93</td><td>17.65</td><td>476.5</td><td>2.4</td><td>-1.35</td><td>0.34</td><td>MIKE</td><td>Y</td><td>A</td></tr><tr><td>DW3</td><td>Crnojević</td><td>202.586867</td><td>-42.191885</td><td>17.26</td><td>18.79</td><td>359.6</td><td>2.4</td><td>-1.12</td><td>0.35</td><td>MIKE</td><td>Y</td><td>New</td></tr><tr><td>KV19-464</td><td>Voggel2020</td><td>202.645456</td><td>-44.666926</td><td>30.24</td><td>17.54</td><td>-20.0</td><td>3.7</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>B</td></tr><tr><td>KV19-492</td><td>Voggel2020</td><td>202.862883</td><td>-42.611324</td><td>12.57</td><td>17.88</td><td>-46.0</td><td>3.6</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>B</td></tr><tr><td>KV19-521</td><td>Voggel2020</td><td>203.050732</td><td>-41.300504</td><td>15.81</td><td>17.87</td><td>-48.9</td><td>4.9</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>B</td></tr><tr><td>KV19-569</td><td>Voggel2020</td><td>203.478428</td><td>-42.362581</td><td>12.39</td><td>18.00</td><td>56.7</td><td>3.4</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>B</td></tr><tr><td>KV19-573</td><td>Voggel2020</td><td>203.537185</td><td>-42.866560</td><td>12.36</td><td>18.50</td><td>-25.4</td><td>3.4</td><td>...</td><td>...</td><td>MIKE</td><td>N</td><td>B</td></tr></tbody></table>

Note. Column 1 shows the Discovery ID for the luminous GC candidates. For 133 targets that were based on preliminary versions of Voggel et al. (2020) and Hughes et al. (2021) and do not have literature names, we name them as GC\_cand with numbers running from 1 to 133. Literature references for the target ID are from van den Bergh et al. (1981), Lauberts (1982), Hesser et al. (1986), Karachentseva & Karachentsev (1998), Harris et al. (2002), Peng et al. (2004), Woodley et al. (2007), Georgiev et al. (2009), Harris et al. (2012), Crnojević et al. (2014, 2016), Taylor et al. (2017), Voggel et al. (2020), and Hughes et al. (2021). Columns 3 and 4 show R.A. and decl. in J2000 respectively. The S/N is shown in Column 5. Column 6 shows the extinction corrected NOAO DR2 g-band magnitude for the target. Columns 7 and 8 the heliocentric radial velocity and its error respectively. Columns 9 and 10 show the derived luminosity-weighted metallicity and its error. Column 11 denotes the instrument and setup used in the observation, with ca and mg being the Calcium Triplet and Magnesium Triplet respectively. For targets observed with MIKE, only the Calcium Triplet measurements are shown in this table. Y in Column 12 denotes if the target has radial velocity expected for Cen A GCs (RV > 250 km s⁻¹), N if it has radial velocity consistent with Milky Way foreground stars, and N/A if we cannot reliably determine its radial velocity. Column 13 shows the literature source of the target. A–E denote the likelihood rank of being a Cen A GC from Voggel et al. (2020), with A and E being more and less likely respectively. RV and Sigma denote if the target has previous literature measured radial velocity and velocity dispersion respectively from Harris et al. (2002), Peng et al. (2004), Martini & Ho (2004), Rejkuba et al. (2007), or Taylor et al. (2010, 2015). Finally, “New” denotes targets that are not in the KV20 catalog, and that have no previous literature kinematic measurements.

(This table is available in machine-readable form.)
<figure><img src="image_14.png" /><figcaption>**Figure 10.** Left: a correlation is seen between the Gaia EDR3 BRexcess and the half-mass radii for Cen A GCs with available literature sizes from McLaughlin et al. (2008). Right: predicted half-mass radii for the same luminous GCs shown in the left using the fit to the correlation in the left panel given in Equation (2). This relation has a scatter of 14%.</figcaption></figure>

## 5. Mass-To-Light Ratios

A primary goal of this work is to find potential stripped nuclei around Cen A that have elevated mass-to-light ratios that indicate the presence of a massive black hole (Mieske et al. 2013; Seth et al. 2014; Voggel et al. 2019). We use the velocity dispersion measurements combined with the half-light mass radii estimates from Section 4.1 to calculate each luminous GC’s virial mass using Equation (1) from Strader et al. (2009),

$$M_{\text{vir}} = \frac{7.5\sigma_{\infty}^2 r_{\text{hm}}}{G} \quad (3)$$

where $\sigma_{\infty}$ is the global velocity dispersion and $r_{\text{hm}}$ is the half-mass radius (see Section 4), and $G$ is the gravitational constant. At the distance of Cen A, luminous GC candidates are partially resolved from ground-based observations, resulting in the derived velocity dispersion being different from the global velocity dispersion ($\sigma_{\infty}$). Due to the declining dispersion with radius in GCs, $\sigma_{\infty}$ will always be lower than our measured velocity dispersion. We calculate this difference by integrating a King66 profile convolved with the seeing over the spectrograph aperture of our observations as previously done in Strader et al. (2009). For clusters with Gaia estimated sizes, we assumed a concentration parameter $c = 30$, a typical value for Local Group GCs. The typical difference between the derived and global velocity dispersion is about 2% at $r_{\text{hm}} = 2.7$ pc, 5% at $r_{\text{hm}} = 4$ pc, and 7% for $r_{\text{hm}} = 7$ pc, with 1 pc $\approx 0.05$. The maximum correction for any cluster in our sample was 15% for cluster VHH81-01, which has a half-mass radius of 1.78. Both our derived dispersion and the calculated $\sigma_{\infty}$ are listed in Table 3.

Figure 11 shows the V-band mass-to-light ratios ($M/L_V$) for our sample of 57 luminous GCs in Cen A. Also shown are GCs from M31 (Strader et al. 2011), UCDs from Virgo and Fornax compiled by Mieske et al. (2013), as well as literature objects from Cen A (Martini & Ho 2004; Rejkuba et al. 2007). Our mass-to-light ratios were computed by dividing the derived virial masses by the calculated V-band luminosities. For Cen A’s literature objects from Martini & Ho (2004) and

Rejkuba et al. (2007), we use updated half-light radii from McLaughlin et al. (2008) to revise the $M/L_V$ estimates presented in the original papers. The half-light radii are then converted to half-mass radii (necessary to get $M/L_V$) using Equation (1). The list of clusters, half-mass radii, and their $M/L_V$ values is shown in Table 4. As discussed in Section 2, we do not include objects from Taylor et al. (2010) and Taylor et al. (2015) in Figure 11 due to their typically low S/N. We also note that the half-light radii used in Taylor et al. (2015) are from unpublished work and are systematically larger than those presented by McLaughlin et al. (2008)—this would bias these values to higher $M/L_V$ values than those presented in our work.

To investigate the $M/L_V$ trends further, we plot their histogram in Figure 12 (blue-shaded region), revealing a bimodal distribution. We also show a kernel density estimate of the same data with a kernel width of 0.1 in red, while a similar kernel density estimate for the 45 M31 clusters with $M_V \le -9.5$ from Strader et al. 2011 are shown in green. We choose to include only the brightest M31 clusters in this comparison to make the sample comparable in brightness to our Cen A clusters, and to reduce the impact of M/L evolution due to relaxation in the lower-mass clusters (e.g., Kruijssen 2008). The bulk of clusters in both samples have $M/L_V$ between 1 and 2. However, in Cen A, the histogram as well as the comparison with M31 reveal a second population of clusters with an elevated $M/L_V \sim 3$. A KolmogorovSmirnov test gives a $>99.6\%$ significance that our observed distribution of $M/L_V$ for luminous GCs in Cen A is different from those of M31 GCs. We also note that the high $M/L_V$ population in Cen A is above the mean value of $\sim 2.15$ inferred by Voggel et al. (2019) from long relaxation M31 and Milky Way GCs and existing Virgo UCD measurements with black hole components removed.

To quantify the fraction of our luminous GCs with elevated $M/L_V$ we used a Gaussian mixture model using the `sklearn` Python package.<fnref n="11" /> After excluding the highest $M/L_V$ cluster VHH81-01 (our most massive and largest luminous GC; more details Section 5.4), we find that a Gaussian mixture model

<footnote n="11">¹¹ https://scikit-learn.org/stable/modules/generated/sklearn.mixture.GaussianMixture.html.</footnote>
<table><caption>Table 3
List of 57 Luminous GCs with Visually Verified Velocity Dispersion</caption><thead><tr><th>ID</th><th>R.V (km s<sup>-1</sup>)</th><th>R.V err (km s<sup>-1</sup>)</th><th>σ (km s<sup>-1</sup>)</th><th>σ err (km s<sup>-1</sup>)</th><th>σ<sub>∞</sub> (km s<sup>-1</sup>)</th><th>setup</th><th>r<sub>hm</sub> (")</th><th>r<sub>hm</sub> Ref</th><th>M<sub>V</sub> (mag)</th><th>E(B-V) (mag)</th><th>M/L<sub>V</sub></th><th>BH Mass (M<sub>☉</sub>)</th><th>Ref</th></tr></thead><tbody><tr><td>HH-22</td><td>615.2</td><td>5.93</td><td>13.07</td><td>1.82</td><td>12.44</td><td>M2FS ca</td><td>0.2498</td><td>Gaia</td><td>-10.18</td><td>0.108</td><td>1.25<sup>+0.44</sup><sub>-0.36</sub></td><td>...</td><td>RV</td></tr><tr><td>T17-1253</td><td>548.3</td><td>5.94</td><td>11.95</td><td>1.49</td><td>11.66</td><td>M2FS ca</td><td>0.1549</td><td>Gaia</td><td>-8.66</td><td>0.106</td><td>2.77<sup>+0.89</sup><sub>-0.73</sub></td><td>1.12<sup>+0.9</sup><sub>-0.6</sub> × 10<sup>5</sup></td><td>New</td></tr><tr><td>HHH86-14</td><td>699.9</td><td>5.92</td><td>15.48</td><td>1.91</td><td>14.12</td><td>M2FS ca</td><td>0.3407</td><td>M08/ACS</td><td>-10.39</td><td>0.109</td><td>1.81<sup>+0.79</sup><sub>-0.49</sub></td><td>...</td><td>RV</td></tr><tr><td>HHH86-30</td><td>780.2</td><td>5.91</td><td>21.97</td><td>4.69</td><td>20.97</td><td>M2FS ca</td><td>0.2352</td><td>Gaia</td><td>-11.02</td><td>0.106</td><td>1.54<sup>+0.82</sup><sub>-0.61</sub></td><td>...</td><td>RV</td></tr><tr><td>K-034</td><td>460.6</td><td>5.91</td><td>14.00</td><td>2.19</td><td>13.15</td><td>M2FS ca</td><td>0.3001</td><td>Gaia</td><td>-10.53</td><td>0.102</td><td>1.21<sup>+0.47</sup><sub>-0.39</sub></td><td>...</td><td>RV</td></tr><tr><td>PFF-gc028</td><td>539.6</td><td>5.92</td><td>10.20</td><td>1.48</td><td>9.90</td><td>M2FS ca</td><td>0.1768</td><td>Gaia</td><td>-9.40</td><td>0.101</td><td>1.15<sup>+0.41</sup><sub>-0.34</sub></td><td>...</td><td>RV</td></tr><tr><td>HHH86-28</td><td>468.1</td><td>5.97</td><td>13.35</td><td>1.27</td><td>12.68</td><td>M2FS ca</td><td>0.2557</td><td>Gaia</td><td>-9.75</td><td>0.122</td><td>1.98<sup>+0.54</sup><sub>-0.43</sub></td><td>...</td><td>RV</td></tr><tr><td>HGHH-G066</td><td>581.4</td><td>5.93</td><td>13.63</td><td>1.68</td><td>13.25</td><td>M2FS ca</td><td>0.1692</td><td>Gaia</td><td>-9.49</td><td>0.101</td><td>1.82<sup>+0.57</sup><sub>-0.47</sub></td><td>...</td><td>RV</td></tr><tr><td>HGHH-43</td><td>497.6</td><td>5.92</td><td>8.31</td><td>1.20</td><td>7.86</td><td>M2FS ca</td><td>0.2584</td><td>M08/ACS</td><td>-9.57</td><td>0.103</td><td>0.91<sup>+0.32</sup><sub>-0.27</sub></td><td>...</td><td>RV</td></tr><tr><td>KV19-273</td><td>574.4</td><td>5.93</td><td>14.26</td><td>1.65</td><td>13.37</td><td>M2FS ca</td><td>0.3118</td><td>Gaia</td><td>-9.59</td><td>0.100</td><td>3.12<sup>+0.96</sup><sub>-0.79</sub></td><td>1.96<sup>+2.33</sup><sub>-0.96</sub> × 10<sup>5</sup></td><td>C</td></tr><tr><td>HGHH-G342</td><td>529.5</td><td>5.92</td><td>13.08</td><td>1.68</td><td>12.49</td><td>M2FS ca</td><td>0.2321</td><td>Gaia</td><td>-10.07</td><td>0.100</td><td>1.30<sup>+0.42</sup><sub>-0.35</sub></td><td>...</td><td>RV</td></tr><tr><td>K-029</td><td>638.8</td><td>5.94</td><td>21.26</td><td>1.13</td><td>20.52</td><td>M2FS ca</td><td>0.1950</td><td>Gaia</td><td>-10.89</td><td>0.100</td><td>1.38<sup>+0.25</sup><sub>-0.22</sub></td><td>...</td><td>RV</td></tr><tr><td>HGHH-G219</td><td>521.7</td><td>5.91</td><td>14.83</td><td>1.33</td><td>14.25</td><td>M2FS ca</td><td>0.2101</td><td>Gaia</td><td>-9.42</td><td>0.099</td><td>2.79<sup>+0.69</sup><sub>-0.58</sub></td><td>1.78<sup>+1.50</sup><sub>-0.78</sub> × 10<sup>5</sup></td><td>RV</td></tr><tr><td>T17-1444</td><td>392.8</td><td>5.93</td><td>13.18</td><td>1.42</td><td>12.78</td><td>M2FS ca</td><td>0.1795</td><td>Gaia</td><td>-9.10</td><td>0.100</td><td>2.57<sup>+0.71</sup><sub>-0.61</sub></td><td>1.24<sup>+1.14</sup><sub>-0.72</sub> × 10<sup>5</sup></td><td>New</td></tr><tr><td>T17-1664</td><td>518.4</td><td>5.93</td><td>13.22</td><td>1.69</td><td>12.96</td><td>M2FS ca</td><td>0.1398</td><td>Gaia</td><td>-9.28</td><td>0.098</td><td>1.75<sup>+0.57</sup><sub>-0.46</sub></td><td>...</td><td>RV</td></tr><tr><td>HH-10</td><td>503.0</td><td>5.92</td><td>20.14</td><td>1.88</td><td>18.19</td><td>M2FS ca</td><td>0.5185</td><td>Gaia</td><td>-10.98</td><td>0.098</td><td>2.66<sup>+0.71</sup><sub>-0.61</sub></td><td>3.22<sup>+6.65</sup><sub>-1.68</sub> × 10<sup>5</sup></td><td>RV</td></tr><tr><td>HHH86-33</td><td>526.6</td><td>5.93</td><td>8.70</td><td>1.35</td><td>8.28</td><td>M2FS ca</td><td>0.2457</td><td>Gaia</td><td>-9.68</td><td>0.103</td><td>0.87<sup>+0.34</sup><sub>-0.27</sub></td><td>...</td><td>RV</td></tr><tr><td>PFF-gc056</td><td>280.3</td><td>5.92</td><td>11.49</td><td>1.22</td><td>11.06</td><td>M2FS ca</td><td>0.2086</td><td>Gaia</td><td>-9.52</td><td>0.099</td><td>1.53<sup>+0.42</sup><sub>-0.35</sub></td><td>...</td><td>RV</td></tr><tr><td>KV19-288</td><td>494.3</td><td>5.93</td><td>15.14</td><td>1.50</td><td>14.02</td><td>M2FS ca</td><td>0.3685</td><td>Gaia</td><td>-10.02</td><td>0.099</td><td>2.72<sup>+0.74</sup><sub>-0.63</sub></td><td>1.90<sup>+2.81</sup><sub>-0.66</sub> × 10<sup>5</sup></td><td>A</td></tr><tr><td>T17-1511</td><td>525.4</td><td>5.92</td><td>19.63</td><td>2.52</td><td>18.78</td><td>M2FS ca</td><td>0.1924</td><td>M08/ACS</td><td>-10.06</td><td>0.099</td><td>2.45<sup>+0.81</sup><sub>-0.69</sub></td><td>2.38<sup>+3.35</sup><sub>-1.74</sub> × 10<sup>5</sup></td><td>RV</td></tr><tr><td>KV19-280</td><td>492.0</td><td>5.95</td><td>16.78</td><td>1.08</td><td>16.26</td><td>M2FS ca</td><td>0.1785</td><td>Gaia</td><td>-9.66</td><td>0.099</td><td>2.47<sup>+0.50</sup><sub>-0.44</sub></td><td>1.90<sup>+1.38</sup><sub>-0.84</sub> × 10<sup>5</sup></td><td>B</td></tr><tr><td>HGHH-19</td><td>621.7</td><td>5.92</td><td>11.24</td><td>1.26</td><td>10.41</td><td>M2FS ca</td><td>0.3159</td><td>M08/ACS</td><td>-10.06</td><td>0.098</td><td>1.24<sup>+0.37</sup><sub>-0.31</sub></td><td>...</td><td>RV</td></tr><tr><td>WHH-22*</td><td>633.9</td><td>5.94</td><td>12.10</td><td>1.92</td><td>11.58</td><td>M2FS ca</td><td>0.1850</td><td>M08/ACS</td><td>-9.83</td><td>0.098</td><td>1.11<sup>+0.44</sup><sub>-0.35</sub></td><td>...</td><td>RV</td></tr><tr><td>KV19-295*</td><td>805.2</td><td>5.95</td><td>13.24</td><td>1.12</td><td>12.98</td><td>M2FS ca</td><td>0.1366</td><td>Gaia</td><td>-9.34</td><td>0.098</td><td>1.61<sup>+0.38</sup><sub>-0.32</sub></td><td>...</td><td>B</td></tr><tr><td>KV19-289</td><td>640.1</td><td>5.92</td><td>18.48</td><td>2.70</td><td>17.72</td><td>M2FS ca</td><td>0.2191</td><td>Gaia</td><td>-10.37</td><td>0.099</td><td>1.87<sup>+0.68</sup><sub>-0.56</sub></td><td>...</td><td>B</td></tr><tr><td>HGHH-G359</td><td>526.1</td><td>6.04</td><td>16.15</td><td>1.02</td><td>15.77</td><td>M2FS ca</td><td>0.1537</td><td>Gaia</td><td>-9.26</td><td>0.099</td><td>2.90<sup>+0.57</sup><sub>-0.51</sub></td><td>2.20<sup>+1.02</sup><sub>-0.78</sub> × 10<sup>5</sup></td><td>RV</td></tr><tr><td>WHH-17</td><td>693.7</td><td>5.92</td><td>16.64</td><td>1.40</td><td>16.11</td><td>M2FS ca</td><td>0.1832</td><td>Gaia</td><td>-9.95</td><td>0.099</td><td>1.90<sup>+0.44</sup><sub>-0.39</sub></td><td>...</td><td>RV</td></tr><tr><td>WHH-18</td><td>790.5</td><td>5.92</td><td>15.14</td><td>1.51</td><td>14.66</td><td>M2FS ca</td><td>0.1822</td><td>Gaia</td><td>-9.78</td><td>0.099</td><td>1.83<sup>+0.49</sup><sub>-0.51</sub></td><td>...</td><td>RV</td></tr><tr><td>HHH86-26</td><td>366.2</td><td>5.94</td><td>12.13</td><td>1.34</td><td>11.47</td><td>M2FS ca</td><td>0.2708</td><td>Gaia</td><td>-10.12</td><td>0.087</td><td>1.22<sup>+0.34</sup><sub>-0.30</sub></td><td>...</td><td>RV</td></tr><tr><td>HGHH-G204</td><td>737.7</td><td>5.92</td><td>16.09</td><td>1.07</td><td>15.26</td><td>M2FS ca</td><td>0.2574</td><td>Gaia</td><td>-9.85</td><td>0.098</td><td>2.62<sup>+0.54</sup><sub>-0.48</sub></td><td>1.90<sup>+1.92</sup><sub>-0.78</sub> × 10<sup>5</sup></td><td>RV</td></tr><tr><td>HGHH-35</td><td>595.7</td><td>5.92</td><td>15.53</td><td>1.32</td><td>14.93</td><td>M2FS ca</td><td>0.2114</td><td>Gaia</td><td>-10.30</td><td>0.098</td><td>1.36<sup>+0.34</sup><sub>-0.27</sub></td><td>...</td><td>RV</td></tr><tr><td>HGHH-G251</td><td>624.5</td><td>5.92</td><td>10.71</td><td>1.39</td><td>10.44</td><td>M2FS ca</td><td>0.1577</td><td>Gaia</td><td>-9.23</td><td>0.098</td><td>1.33<sup>+0.44</sup><sub>-0.35</sub></td><td>...</td><td>RV</td></tr><tr><td>pff-kc-100</td><td>516.6</td><td>5.96</td><td>12.44</td><td>1.69</td><td>11.91</td><td>M2FS ca</td><td>0.2233</td><td>Gaia</td><td>-9.86</td><td>0.099</td><td>1.38<sup>+0.48</sup><sub>-0.38</sub></td><td>...</td><td>RV</td></tr><tr><td>H12_194</td><td>508.3</td><td>6.02</td><td>13.81</td><td>1.56</td><td>13.33</td><td>M2FS ca</td><td>0.1947</td><td>Gaia</td><td>-9.10</td><td>0.096</td><td>3.02<sup>+0.90</sup><sub>-0.74</sub></td><td>1.72<sup>+1.38</sup><sub>-0.84</sub> × 10<sup>5</sup></td><td>New</td></tr><tr><td>HHH86-34</td><td>648.5</td><td>5.92</td><td>14.95</td><td>2.28</td><td>14.23</td><td>M2FS ca</td><td>0.2457</td><td>Gaia</td><td>-9.85</td><td>0.097</td><td>2.19<sup>+0.83</sup><sub>-0.68</sub></td><td>...</td><td>RV</td></tr><tr><td>H12_106</td><td>595.8</td><td>5.91</td><td>11.79</td><td>2.80</td><td>10.86</td><td>M2FS ca</td><td>0.3908</td><td>Gaia</td><td>-9.93</td><td>0.096</td><td>1.88<sup>+1.13</sup><sub>-0.85</sub></td><td>...</td><td>A</td></tr><tr><td>HGHH-41</td><td>360.0</td><td>5.92</td><td>12.79</td><td>1.18</td><td>11.90</td><td>M2FS mg</td><td>0.3233</td><td>M08/STIS</td><td>-9.66</td><td>0.115</td><td>2.39<sup>+0.37</sup><sub>-0.35</sub></td><td>1.12<sup>+1.80</sup><sub>-0.36</sub> × 10<sup>5</sup></td><td>Sigma</td></tr><tr><td>HGHH-12</td><td>441.4</td><td>5.92</td><td>15.60</td><td>1.63</td><td>14.81</td><td>M2FS mg</td><td>0.2462</td><td>Gaia</td><td>-10.35</td><td>0.106</td><td>1.49<sup>+0.23</sup><sub>-0.22</sub></td><td>...</td><td>Sigma</td></tr><tr><td>HHH86-29</td><td>729.2</td><td>5.92</td><td>16.19</td><td>1.64</td><td>14.90</td><td>M2FS mg</td><td>0.3628</td><td>M08/ACS</td><td>-10.25</td><td>0.112</td><td>2.46<sup>+0.39</sup><sub>-0.36</sub></td><td>1.60<sup>+3.71</sup><sub>-0.36</sub> × 10<sup>5</sup></td><td>Sigma</td></tr><tr><td>HGHH-44</td><td>508.3</td><td>5.94</td><td>12.48</td><td>1.45</td><td>11.93</td><td>M2FS mg</td><td>0.2642</td><td>M08/STIS</td><td>-9.52</td><td>0.099</td><td>2.23<sup>+0.35</sup><sub>-0.34</sub></td><td>1.12<sup>+1.14</sup><sub>-0.54</sub> × 10<sup>5</sup></td><td>Sigma</td></tr><tr><td>H12_95</td><td>902.3</td><td>5.93</td><td>15.62</td><td>1.20</td><td>14.92</td><td>M2FS mg</td><td>0.2318</td><td>Gaia</td><td>-10.05</td><td>0.090</td><td>1.88<sup>+0.29</sup><sub>-0.27</sub></td><td>...</td><td>A</td></tr><tr><td>VHH81-01</td><td>640.0</td><td>5.92</td><td>17.56</td><td>1.86</td><td>14.81</td><td>M2FS mg</td><td>1.7821</td><td>This Work</td><td>-10.80</td><td>0.118</td><td>7.17<sup>+1.14</sup><sub>-1.08</sub></td><td>8.61<sup>+10.3</sup><sub>-0.12</sub> × 10<sup>5</sup></td><td>Sigma</td></tr></tbody></table>
<table><caption>Table 3
(Continued)</caption><thead><tr><th>ID</th><th>R.V (km s<sup>-1</sup>)</th><th>R.V err (km s<sup>-1</sup>)</th><th>σ (km s<sup>-1</sup>)</th><th>σ err (km s<sup>-1</sup>)</th><th>σ<sub>∞</sub> (km s<sup>-1</sup>)</th><th>setup</th><th>r<sub>hm</sub> (")</th><th>r<sub>hm</sub> Ref</th><th>M<sub>V</sub> (mag)</th><th>E(B-V) (mag)</th><th>M/L<sub>V</sub></th><th>BH Mass (M<sub>☉</sub>)</th><th>Ref</th></tr></thead><tbody><tr><td>VHH81-03</td><td>558.4</td><td>5.92</td><td>16.38</td><td>1.73</td><td>15.59</td><td>M2FS mg</td><td>0.2576</td><td>Gaia</td><td>-10.65</td><td>0.101</td><td>1.32<sup>+0.21</sup><sub>-0.19</sub></td><td>...</td><td>Sigma</td></tr><tr><td>T17-1412</td><td>670.2</td><td>5.92</td><td>20.37</td><td>0.80</td><td>19.86</td><td>M2FS mg</td><td>0.1619</td><td>Gaia</td><td>-10.30</td><td>0.099</td><td>1.85<sup>+0.26</sup><sub>-0.25</sub></td><td>...</td><td>Sigma</td></tr><tr><td>H12_141</td><td>427.1</td><td>5.91</td><td>9.64</td><td>1.53</td><td>9.07</td><td>M2FS mg</td><td>0.3021</td><td>Gaia</td><td>-9.70</td><td>0.093</td><td>1.25<sup>+0.22</sup><sub>-0.20</sub></td><td>...</td><td>New</td></tr><tr><td>HHH86-38</td><td>405.1</td><td>5.93</td><td>12.56</td><td>2.34</td><td>12.19</td><td>M2FS mg</td><td>0.2172</td><td>Gaia</td><td>-9.72</td><td>0.087</td><td>1.60<sup>+0.31</sup><sub>-0.27</sub></td><td>...</td><td>Sigma</td></tr><tr><td>aat329848</td><td>552.0</td><td>2.43</td><td>14.20</td><td>1.41</td><td>13.90</td><td>MIKE</td><td>0.2544</td><td>Gaia</td><td>-9.95</td><td>0.095</td><td>1.96<sup>+0.29</sup><sub>-0.29</sub></td><td>...</td><td>RV</td></tr><tr><td>Fluffy</td><td>764.3</td><td>2.46</td><td>6.51</td><td>2.14</td><td>5.89</td><td>MIKE</td><td>1.6590</td><td>Crnojević</td><td>-9.67</td><td>0.093</td><td>2.99<sup>+0.85</sup><sub>-0.71</sub></td><td>7.60<sup>+21</sup><sub>-3.0</sub> × 10<sup>4</sup></td><td>RV</td></tr><tr><td>DW3</td><td>359.6</td><td>2.42</td><td>8.82</td><td>1.37</td><td>8.60</td><td>MIKE</td><td>0.2546</td><td>Gaia</td><td>-9.49</td><td>0.098</td><td>1.15<sup>+0.20</sup><sub>-0.18</sub></td><td>...</td><td>New</td></tr><tr><td>ESO269-06</td><td>744.0</td><td>2.42</td><td>11.37</td><td>0.91</td><td>10.87</td><td>MIKE</td><td>0.3337</td><td>This Work</td><td>-9.88</td><td>0.081</td><td>1.69<sup>+0.25</sup><sub>-0.24</sub></td><td>...</td><td>RV</td></tr><tr><td>pff_gc-098</td><td>609.9</td><td>2.42</td><td>14.93</td><td>1.12</td><td>14.62</td><td>MIKE</td><td>0.2028</td><td>Gaia</td><td>-9.92</td><td>0.093</td><td>1.79<sup>+0.26</sup><sub>-0.26</sub></td><td>...</td><td>RV</td></tr><tr><td>KV19-212</td><td>571.5</td><td>2.42</td><td>19.38</td><td>1.13</td><td>18.84</td><td>MIKE</td><td>0.2725</td><td>Gaia</td><td>-10.33</td><td>0.111</td><td>2.73<sup>+0.39</sup><sub>-0.39</sub></td><td>3.46<sup>+2.81</sup><sub>-0.9</sub> × 10<sup>5</sup></td><td>A</td></tr><tr><td>KK197-NSC</td><td>639.7</td><td>2.42</td><td>12.91</td><td>1.33</td><td>12.55</td><td>MIKE</td><td>0.2111</td><td>G09/ACS</td><td>-9.80</td><td>0.133</td><td>1.53<sup>+0.23</sup><sub>-0.22</sub></td><td>...</td><td>RV</td></tr><tr><td>VHH81-5</td><td>563.2</td><td>2.42</td><td>13.13</td><td>1.75</td><td>12.44</td><td>MIKE</td><td>0.7707</td><td>This Work</td><td>-10.63</td><td>0.101</td><td>2.55<sup>+0.43</sup><sub>-0.40</sub></td><td>1.96<sup>+4.13</sup><sub>-0.54</sub> × 10<sup>5</sup></td><td>Sigma</td></tr><tr><td>KV19-442</td><td>476.5</td><td>2.42</td><td>12.63</td><td>2.53</td><td>11.95</td><td>MIKE</td><td>0.4750</td><td>Gaia</td><td>-10.55</td><td>0.086</td><td>1.57<sup>+0.31</sup><sub>-0.28</sub></td><td>...</td><td>A</td></tr><tr><td>H12_78</td><td>657.3</td><td>2.42</td><td>20.59</td><td>0.85</td><td>20.18</td><td>MIKE</td><td>0.2270</td><td>Gaia</td><td>-10.25</td><td>0.088</td><td>2.82<sup>+0.39</sup><sub>-0.39</sub></td><td>4.59<sup>+2.4</sup><sub>-1.25</sub> × 10<sup>5</sup></td><td>A</td></tr><tr><td>KV19-271</td><td>548.3</td><td>2.42</td><td>21.89</td><td>1.57</td><td>21.41</td><td>MIKE</td><td>0.2214</td><td>Gaia</td><td>-10.41</td><td>0.103</td><td>2.65<sup>+0.39</sup><sub>-0.38</sub></td><td>4.47<sup>+2.76</sup><sub>-1.37</sub> × 10<sup>5</sup></td><td>A</td></tr></tbody></table>

Note. Columns 1–3 are identical to Columns 1, 6, and 7 in Table 2. Columns 4, 5, and 6 show the derived velocity dispersion, its error, and the global velocity dispersions (see Section 5) respectively. In Column 7 are the calculated half-mass radii in arcseconds. Column 8 denotes the source of the calculated half-mass radii, with Gaia being the BR<sub>excess</sub>-half-mass radii relation described in Section 4; M08/ACS and M08/STIS are sizes from McLaughlin et al. (2008). Column 9 shows the extinction corrected absolute V-band magnitude (assuming a distance modulus of (m − M)<sub>V</sub> = 27.91). Column 10 shows the Galactic dust reddening used in column 9. Column 11 shows the calculated V-band mass-to-light ratio. Column 11 shows the predicted black hole mass necessary for luminous GCs with M/L<sub>V</sub> ≥ 2.3 to reproduce the observed elevated M/L<sub>V</sub>. Column 13 is identical to column 13 in Table 2. We highlight (*) two luminous GCs with probably incorrect V-band luminosity (see Section 4).

(This table is available in machine-readable form.)
<figure><img src="image_15.png" /><figcaption>**Figure 11.** Luminosity of stripped nuclei and GCs compared with their $M/L_V$. Solid red circles are the 57 objects from this paper, while lighter red points are Cen A objects from the literature, and gray points are from other galaxies (see text for details). The horizontal dashed lines are the best fit and scatter of the stellar mass-to-light ratios of long relaxation systems from Voggel et al. (2019).</figcaption></figure>

with 2 components best describes the observed distribution of $M/L_V$, with the lower $M/L_V$ population peaking at $M/L_V = 1.51$ with a standard deviation of 0.32. The higher $M/L_V$ peak is at 2.68 with a standard deviation of 0.21. The Gaussian mixture model suggests that 35.2% of our sample of luminous GCs (20/57) have an inflated $M/L_V$. This is the same as the number of objects that are above $M/L_V$ of 2.3, which represents the dividing line where the probability of being in the lower and upper $M/L_V$ population is equal. Relative to M31, we find $2.53 \times$ more luminous GCs above $M/L_V$ of 2.3.

One expectation from stellar models that is not borne out in observations is that the $M/L_V$ should be metallicity dependent; this has also been found in previous work (Strader et al. 2011; Bruzual et al. 2013). We find no significant evidence of any trend of $M/L_V$ with our derived metallicity (see Section 3.6) or PISCS $g-r$ color. We note that for two objects, KV19-295 and WHH-22, our $M/L_V$ values may be incorrect due to bad $g-r$ colors used to estimate their V-band luminosity (see Appendix); their $M/L_V$ values are 1.6 and 1.1, and thus both belong to the lower $M/L$ population.

## 5.1. Nuclear Star Clusters

Our observations include four nuclear star clusters of present day galaxies. Of these, we were able to estimate mass-to-light ratios in three, *KK197-NSC*, *ESO269-06*, and *DW3*, from Crnojević et al. (2016). All three galaxies have total V-band luminosities of $<4 \times 10^7 L_\odot$ (Crnojević et al. 2019) and thus stellar masses of $\lesssim 10^8 M_\odot$. The nuclear star clusters have $M/L_V$ of 1.13, 1.69, and 1.15 respectively, and thus none is consistent with being elevated and having high mass fraction black holes. Their virial masses range from $6 \times 10^5 M_\odot$ in *DW3* to $1.2 \times 10^6 M_\odot$ in *ESO269-06*. We note that *KK197-NSC* has a dynamical mass-to-light ratio estimate from Fahrion et al. (2020). We find a $\sim 3.5 \times$ lower $M/L_V$ than their published value of $M/L_V = 5.65 \pm 0.5$. This disagreement is due solely to their derived global velocity dispersion of $24.8 \pm 0.8 \text{ km s}^{-1}$ from

<figure><img src="image_16.png" /><figcaption>**Figure 12.** Histogram of the distribution of the $M/L_V$ for the 57 luminous GC. A clear bimodality is seen in our data. A one-dimensional Kernel Density Estimation for our luminous GC is shown in red, compared with a similar estimate for M31 globular clusters (shown in green). The black dashed lines show the two mixture models for the best Gaussian mixture model for our luminous GCs. We find a clear bimodality with “normal” GCs peaking at $M/L_V = 1.51$, and luminous GCs with inflated $M/L_V$ peaking at $M/L_V = 2.68$. The two populations are divided at $M/L_V = 2.3$. The outlier in $M/L_V$ is our most massive luminous GC VH81-01 (more details Section 5.4).</figcaption></figure>

Very Large Telescope (VLT) Ultraviolet and Visual Echelle Spectrograph (UVES) data, which is a factor of $\sim 2 \times$ higher than our global velocity dispersion of $12.5 \pm 0.4 \text{ km s}^{-1}$. For comparison we fitted the MIKE Calcium Triplet spectrum of KK197-NSC with a fixed velocity dispersion of $24.8 \text{ km s}^{-1}$ from Fahrion et al. (2020). The fit has a reduced $\chi^2$ of 1.48; this is 0.06 higher than our best fit reduced $\chi^2$ of 1.42, a difference of more than $3\sigma$. Additionally, the velocity dispersion measurement for the (lower S/N) MIKE Magnesium Triplet spectra of $15.3 \pm 4.3 \text{ km s}^{-1}$ is consistent with our best-fit MIKE Calcium Triplet velocity dispersion within the errors. We believe that the difference in velocity dispersion arises from the difference in extraction apertures. We use MIKE data with a $1''$ slit diameter and an optimal extraction with FWHM of $0.2''$81. The extraction aperture in Fahrion et al. (2020) was significantly larger, $1.2 \times 4.0''$, and thus may be dominated by the kinematics of the galaxy. Thus overall, we find that none of the nuclei has inflated mass-to-light ratios. Either these nuclei have no central black holes, or their black holes are lower mass than we can detect. As we show below, we can only detect black holes with $\gtrsim 10^4 M_\odot$ (or $\gtrsim 4\%$ of the cluster mass).

## 5.2. BH Mass Estimates for Luminous GCs

The population of high $M/L_V$ objects could be due to the presence of massive black holes. This idea was suggested by Mieske et al. (2013), and the presence of black holes indicated by enhanced $M/L_V$ values was verified in five high-mass UCDs in Virgo (Seth et al. 2014; Ahn et al. 2017, 2018; Afanasiev et al. 2018), as well as in the nuclei of galaxies (Pechetti et al. 2017; Krajnović et al. 2018). The finding of high mass fraction black holes in UCDs/luminous GCs is a strong indication of them being stripped galaxy nuclei. In this section we provide an estimate for the hypothetical central black hole (BH) mass for the 20 luminous GCs with elevated mass-to-light ratios ($M/L_V > 2.3$). The basic assumption we make here is that the
<figure><img src="image_17.png" /><figcaption>**Figure 13.** Left: predicted black hole masses for 20 luminous GCs in Cen A with inflated mass-to-light ratios versus their absolute V-band magnitudes (blue squares). Solid squares show luminous GCs with $M/L_V$ enhancements >3$\sigma$, while open squares have less significant $M/L_V$ enhancements. Gray stars are black hole mass predictions for stripped nuclei from Mieske et al. (2013). The five known black hole masses in UCDs from Seth et al. (2014), Ahn et al. (2017, 2018), and Afanasiev et al. (2018) are shown in red triangles together with two upper limits for two UCDs from Voggel et al. (2018) and the recent BH mass estimate from the most massive M31 globular cluster (B023-G078; $M_V = -11.4$) by Pechetti et al. (2022). Right: the X-axis shows the mass for 20 luminous GCs based on their V-band luminosity ($L_V$) from Table 3 assuming a $M/L_V = 1.51$ ($Mass_{pop} = L_V \times 1.51$). The Y-axis shows the predicted NSC mass based on the inferred black hole in the left panel using the empirical relation between black hole and total galaxy stellar mass (Reines & Volonteri 2015, Equation (4)) and total galaxy stellar mass and NSC mass (Neumayer et al. 2020, Equation (5)). The blue error bar indicates the uncertainty in both quantities: the vertical error bar is dominated by the scatter in the scaling relations, and the horizontal error bar is determined based on the width of the lower $M/L_V$ component in Figure 12. Objects close to the one-to-one line (black dashed) are consistent with being stripped galaxy nuclei.</figcaption></figure>

<table><caption>**Table 4**
List of Updated Mass-to-light Ratios for Literature Globular Clusters</caption><thead><tr><th>ID</th><th>R.A.<br>(deg)</th><th>Decl.<br>(deg)</th><th>σ<br>(km s<sup>-1</sup>)</th><th>M<sub>v</sub><br>(mag)</th><th>r<sub>hm</sub><br>(pc)</th><th>M/L<sub>v</sub></th></tr></thead><tbody><tr><td>HGHH92-C7</td><td>201.522542</td><td>-42.942333</td><td>21.10</td><td>-11.09</td><td>6.82</td><td>2.22<sup>+0.07</sup><sub>-0.07</sub></td></tr><tr><td>HGHH92-C11</td><td>201.228042</td><td>-43.022694</td><td>19.20</td><td>-10.35</td><td>10.67</td><td>5.68<sup>+0.80</sup><sub>-0.75</sub></td></tr><tr><td>HGHH92-C12</td><td>201.273833</td><td>-43.175194</td><td>13.10</td><td>-10.52</td><td>7.05</td><td>1.49<sup>+0.19</sup><sub>-0.17</sub></td></tr><tr><td>HGHH92-C17</td><td>201.415542</td><td>-42.933111</td><td>20.90</td><td>-10.63</td><td>7.41</td><td>3.61<sup>+0.64</sup><sub>-0.58</sub></td></tr><tr><td>HGHH92-C21</td><td>201.469750</td><td>-43.096222</td><td>19.00</td><td>-10.39</td><td>9.19</td><td>4.62<sup>+0.48</sup><sub>-0.47</sub></td></tr><tr><td>HGHH92-C22</td><td>201.473208</td><td>-42.985444</td><td>17.90</td><td>-10.11</td><td>4.99</td><td>2.88<sup>+0.18</sup><sub>-0.17</sub></td></tr><tr><td>HGHH92-C23</td><td>201.477417</td><td>-42.990389</td><td>30.50</td><td>-11.66</td><td>4.46</td><td>1.79<sup>+0.14</sup><sub>-0.13</sub></td></tr><tr><td>HGHH92-C29</td><td>201.168292</td><td>-43.301472</td><td>16.10</td><td>-10.11</td><td>6.68</td><td>3.12<sup>+0.47</sup><sub>-0.42</sub></td></tr><tr><td>HGHH92-C36</td><td>201.532208</td><td>-42.866750</td><td>15.70</td><td>-9.91</td><td>4.14</td><td>2.21<sup>+0.74</sup><sub>-0.61</sub></td></tr><tr><td>HGHH92-C37</td><td>201.544083</td><td>-42.895194</td><td>12.60</td><td>-9.83</td><td>3.04</td><td>1.13<sup>+0.33</sup><sub>-0.28</sub></td></tr><tr><td>HGHH92-C41</td><td>201.162417</td><td>-43.335111</td><td>11.50</td><td>-9.67</td><td>5.96</td><td>2.13<sup>+0.75</sup><sub>-0.61</sub></td></tr><tr><td>HGHH92-C44</td><td>201.382208</td><td>-43.322944</td><td>13.10</td><td>-9.57</td><td>4.87</td><td>2.48<sup>+0.49</sup><sub>-0.44</sub></td></tr><tr><td>HCH99 21</td><td>201.394375</td><td>-43.057694</td><td>10.60</td><td>-10.28</td><td>3.92</td><td>0.68<sup>+0.34</sup><sub>-0.27</sub></td></tr><tr><td>R223</td><td>201.386667</td><td>-43.117278</td><td>14.40</td><td>-9.49</td><td>3.09</td><td>2.04<sup>+0.67</sup><sub>-0.55</sub></td></tr><tr><td>R261</td><td>201.303750</td><td>-43.133083</td><td>14.60</td><td>-10.06</td><td>2.63</td><td>1.06<sup>+0.27</sup><sub>-0.24</sub></td></tr></tbody></table>

**Note.** Column 1 shows the name of the GC as identified in Rejkuba et al. (2007). Column 4 shows the derived velocity dispersion from Rejkuba et al. (2007). Column 5 shows the extinction corrected V-band absolute magnitude from Rejkuba et al. (2007). Column 6 shows the corresponding half-mass radii using transformation 1 with half-light radii from McLaughlin et al. (2008). Column 7 shows the updated V-band mass-to-light ratio. We calculated the mass-to-light ratio by taking the ratio of virial mass from Equation (3) using a central velocity dispersion based in values of Column 4 with the V-band luminosity from Column 5. For the central velocity dispersion we assumed a 6% correction between values of column 4 and $\sigma_\infty$ based on the average correction by Rejkuba et al. (2007).

inflated $M/L_V$ values are due to the presence of a black hole. We create dynamical models to derive the black hole mass required in each object assuming the true stellar $M/L_V$ is given by the peak of the lower Gaussian mixture model component of 1.51 (see Section 5). This then provides a rough estimate of the masses of the possible black holes in these systems.

We first created a synthetic 1D King62 light profile for each object (due to the availability of an analytic expression for the King62 models). For objects with HST measurements, we used their corresponding concentration (c) and half-light radii, while for those where our half-light radii are from Gaia, we assume a concentration parameter c = 30. We then fit a Multi Gaussian
Expansion (MGE) model (Cappellari 2002) to the 1D King62 light profiles. Next, we use the MGE models as an ingredient in Jeans dynamical models (as implemented in the spherical version of the Jeans Anisotropic Modeling (JAM) software; Cappellari 2008). These models use the MGE light profiles of the clusters to predict the velocity dispersion within the observed aperture as a function of two free parameters: the stellar mass-to-light ratio and black hole mass. For this modeling, we assume the orbits of stars in the cluster are isotropic. Comparison of the predicted dispersion to the observed dispersion enables constraints on the mass-to-light ratio and BH mass. We note that without a black hole, the derived $M/L_V$ for the clusters agrees extremely well with the virial mass measurements presented above (well within the $1\sigma$ errors), suggesting that the differences created by translating the effective radii and concentrations of King66 to King62 models are negligible. Next, we fixed the stellar mass-to-light ratio to 1.51, the mean $M/L_V$ for clusters with lower $M/L_V$ (see Section 5). Using this stellar $M/L_V$, we run a set of JAM models with a grid of increasing BH masses to simulate the effect of a BH on the integrated velocity dispersion. The BH mass that gives the closest velocity dispersion to the observed value is picked as the best BH mass. We obtained an upper and lower limit for the predicted BH mass using the errors in the $M/L_V$ of each individual luminous GC.

The predicted BH masses versus their V magnitude are shown in the left panel of Figure 13, and their BH masses are listed in Table 3. We distinguish luminous GCs with significant BH mass predictions (BH mass $3 \times$ above their lower error) with solid blue squares from less significant BH mass predictions (open blue squares). We also plot BHs determined in a similar way from Mieske et al. (2013). Our luminosity-BH relationship follows a similar trend to that found in Mieske et al. (2013), extending the predicted BH mass for luminous GCs down to $M_V$ fainter than $-9.5$ ($M_V > -9.5$).

We find that BH masses of 4%–18% of the luminous GC virial mass (as calculated in Section 5) explain the inflated $M/L_V$ that we observe, with a mean BH mass of $3.3 \times 10^5 M_\odot$ and a maximum BH mass of $8.61_{-0.12}^{+10.3} \times 10^5 M_\odot$ for the luminous GC VHH81-01, which we describe in more detail at the end of this section.

### 5.3. A Consistency Check for the Tidal Stripping Formation Scenario

We can test the plausibility of the stripped nuclei hypothesis by comparing the stellar mass of the clusters with a predicted NSC mass inferred from scaling relationships between black holes, NSCs, and their host galaxies similar to what was done in Graham (2020). If the luminous GCs with elevated $M/L_V$ are the remnant stripped nuclei of galaxies, we expect their stellar mass to be comparable with the NSC mass of their progenitor galaxy (Pfeffer & Baumgardt 2013). We therefore use our inferred black hole mass in each cluster to predict the progenitor NSC mass and compare this with the observed cluster stellar mass. Because of the large scatter in the scaling relations, this test provides only an order of magnitude-level consistency check.

We estimate the cluster stellar mass based on their V-band luminosity with an assumed $M/L_V$ of 1.51—the peak lower component of the Gaussian mixture model of Figure 12; we call this quantity MassPop. We use MassPop rather than a virial mass, because if these clusters do indeed have high mass fraction

black holes, our virial masses overestimate the stellar mass of the clusters. We then compare this mass with the NSC mass predicted based on the BH mass. To predict the NSC mass, we first infer the progenitor galaxy stellar mass based on the BH mass—total galaxy stellar mass from Reines & Volonteri (2015). A simple rearrangement of their Equation (4) with constants from their Equation (5) give us the following relation between galaxy stellar mass and BH mass:

$$M_* = 10^{\frac{\log(M_{BH}) - 7.45 \pm 0.08}{1.05 \pm 0.11}} \times 10^{11}[M_\odot] \quad (4)$$

where $M_*$ is the galaxy stellar mass and $M_{BH}$ the BH mass. Reines & Volonteri (2015) report a 0.55 dex scatter around this relation. The $M_*$ is then translated back into an expected NSC mass using Equation (1) from Neumayer et al. (2020):

$$\log(M_{NSC}) = 0.48 \log \left( \frac{M_*}{10^9 M_\odot} \right) + 6.51 \quad (5)$$

with $M_{NSC}$ being the NSC mass. Neumayer et al. (2020) report a 0.6 dex scatter around this relation. The comparison of the MassPop values and the predicted NSC mass are shown in the right panel of Figure 13. We calculated the errors in the predicted NSC mass by combining (in quadrature) the scatter of Equations (4) and (5). We find a good agreement between our MassPop and predicted NSC masses, with a mean difference of 0.11 dex for our significant BH predictions (those with $3\sigma M/L_V$ enhancements; these are shown as solid blue squares). This agreement is surprisingly good—the difference is much smaller than the scatter of relations from Reines & Volonteri (2015) and Neumayer et al. (2020). We also show data from similar measurements by Mieske et al. (2013) and literature UCDs with dynamical BH masses (Seth et al. 2014; Ahn et al. 2017, 2018; Afanasiev et al. 2018) and a recent BH mass estimate from the most massive M31 GC by Pechetti et al. (2022). For objects in Mieske et al. (2013), we estimated the NSC mass by multiplying their V-band luminosities with their $M/L_V$ based on stellar population models for each individual object in Mieske et al. (2013). For the dynamical measurements, the stellar mass estimates on the y-axis are dynamically estimated based on the inner components of the UCDs. These show a rough agreement with the predictions with a few outliers including M59-UCD3 ($\log(\text{MassPop}) \approx 8.2$) (Ahn et al. 2018).

We also made a similar comparison using the NSC mass—black hole mass relation derived by Graham (2020), who previously showed the good agreement between the BH masses and stellar masses for the UCDs with dynamical BH mass estimates. The Graham (2020) relation (their Equation (8)) combines the previous NSC-spheroid (Graham 2016) and black hole mass-spheroid (Scott et al. 2013) relationships to get a direct correlation between the NSC and BH masses. The agreement is not as good as using the total stellar mass relations above; we find the MassPop is on average 0.5 dex lower than the predicted NSC masses using the Graham (2020) relation for our significant BH detections. This discrepancy could be due to the extrapolation of the Scott et al. (2013) relation to lower BH masses than the galaxies it was based on, or simply due to the large scatter in this relationship (black hole masses have a range of ~2 dex at a given spheroid mass).

Overall, these comparisons support the idea that some of our luminous GCs are the remnant NSCs of stripped galaxies. We
stress here that these inflated mass-to-light ratio objects are likely just a subset of all the stripped nuclei around Cen A, because stripped nuclei could lack BHs or have BHs with mass fractions too small for us to detect.

As an alternative to central black holes, the inflated mass-to-light ratios could be due to tidal effects during stripping (Forbes et al. 2014). However, two points argue against this: (1) elevated mass-to-light ratios are seen in nearly a third of our luminous GCs, while inflated mass-to-light ratios due to tidal effects should be limited in duration and thus frequency, and (2) we see no trend of the fraction of luminous GCs with inflated mass-to-light ratios with radius. We find a mean galactocentric radius of 21.2 and 21.8 kpc for luminous GCs with inflated and non-inflated $M/L_V$ respectively.

Another possibility is that the inflated mass-to-light ratios are due to variations from the canonical initial stellar mass function (IMF) in luminous GCs. Both top-heavy IMFs that would produce large numbers of stellar remnants (Dabringhausen et al. 2009) and bottom-heavy IMFs that would produce an abundance of low-mass stars (Mieske & Kroupa 2008) could explain the apparent high mass-to-light ratios. However, the dynamical detection of central SMBHs in massive UCDs (Seth et al. 2014; Ahn et al. 2017, 2018; Afanasiev et al. 2018) argues against these interpretations, because they show that the mass-to-light ratio clearly rises toward the center, and the outer mass-to-light ratio are consistent (or lighter than) predictions from stellar population models with standard IMFs. Additionally, a metallicity and density dependent IMF combined with a mass dependent BH retention fraction has been proposed to explain the $M/L_V$ seen in UCDs (Jeřábková et al. 2017; Mahani et al. 2021). The mass segregation of the stellar mass BHs can produce a compact subcluster of BHs in lower-mass UCDs, such as those we discuss here, that raises their inferred $M/L_V$, although this mechanism cannot explain the central dispersion rises in the most massive UCDs ($>10^8 M_\odot$). Related work by Kroupa et al. (2020) suggests that a merger of the stellar mass BHs to form a central massive SMBH can occur at the centers of galaxies with spheroid masses $\gtrsim 10^9 M_\odot$; this threshold is close to the inferred spheroid masses in our sample of luminous GCs.

## 5.4. VHH81-01, a Very Massive Cen A Cluster

The cluster VHH81-01 has the highest mass-to-light ratio in our sample with $M/L_V = 7.16_{-1.0}^{+1.16}$, and also the highest predicted black hole mass. The virial mass estimate is $1.25 \times 10^7 M_\odot$, nearly identical to the Cen A cluster HCH99 18 from (Rejkuba et al. 2007), with a $M/L_V = 4.7_{-1.6}^{+1.2}$ (which they also suggest is a stripped galaxy nucleus). VHH81-01 has one of the two highest virial mass estimates of all clusters in Cen A.

VHH81-01 has literature velocity dispersion measurements from several sources (Rejkuba et al. 2007; Taylor et al. 2010, 2015). The Rejkuba et al. (2007) UVES dispersion is shown in Figure 6 and is $4.6 \text{ km s}^{-1}$ lower than our derived dispersion of $17.6 \pm 0.8 \text{ km s}^{-1}$. While the UVES data Rejkuba et al. (2007) is higher resolution, their global dispersion of $12.4 \pm 0.8 \text{ km s}^{-1}$ agrees within the 1 sigma errors with our global dispersion of $14.8 \pm 1.8 \text{ km s}^{-1}$. Our derived dispersion agrees well with the values from Taylor et al. (2010), $15.9 \pm 1.6 \text{ km s}^{-1}$, and Taylor et al. (2015), $17.3 \pm 0.8 \text{ km s}^{-1}$. If we assume the $12.4 \pm 0.8 \text{ km s}^{-1}$ global velocity dispersion reported in Rejkuba et al. (2007) as the true value,

<figure><img src="image_18.png" /><figcaption>**Figure 14.** Color cutout of VHH81-01 from ground-based PISCeS imaging at the 6.5 m telescope Magellan Clay (Crnojević et al. 2016). The cutout is $0.8' \times 0.8'$ in size, and oriented such that north is up and east is left.</figcaption></figure>

we still get a high a mass-to-light ratio of $M/L_V = 4.91_{-0.48}^{+0.63}$ and a predicted BH mass of $4.96_{-1.2}^{+1.51} \times 10^5 M_\odot$, thus giving qualitatively similar results.

Our effective radius estimate of $1.7'' (31.5 pc) derived from ground-based PISCeS imaging data (see Figure 14) is in good agreement with that from Taylor et al. (2015), which is from unpublished ground-based analysis by M. Goméz. Given the good seeing and large effective radius, we do not think that our size estimate could be falsely inflating the mass-to-light ratio. Furthermore we do not observe an unusual $g-r$ color for VHH81-01 that could underestimate its $L_V$ and produce an inflated $M/L_V$. Therefore, it appears that this object truly has a high mass-to-light ratio and is the most likely of all of our objects to host a high mass fraction black hole.

In addition to VHH81-01, there are two other objects in Rejkuba et al. (2007), HGGH92-C11 and HGGH92-C21, that have similarly high $M/L_V$ to VHH81-01. All three of these objects are highly flattened, with ellipticity $\gtrsim 0.25$ (greater than any MW GCs). We know that many nuclear star clusters are quite flattened, both in late-type galaxies and in massive early types (Seth et al. 2006; Spengler et al. 2017; Neumayer et al. 2020). HGGH92-C21 has an upper limit in the black hole mass of $1 \times 10^6 M_\odot$ from Voggel et al. (2018) (published there as UCD320), corresponding to a BH mass fraction of 38%. Voggel et al. (2018) also found a much lower $M/L$ than previously published work due to a smaller derived effective radius for HGGH92-C21.

## 6. Conclusions

In this paper we present new high-resolution spectral data from M2FS and MIKE for 321 luminous GC candidates around Cen A. Of the 321 luminous GC candidates we can reliably determine the radial velocities for 219. Based on their radial velocities, we discover that 78 luminous GCs are members of Cen A, of which 27 are new discoveries. Of these 78, we can reliably measure the velocity dispersion of 57, including first
<figure><img src="image_19.png" /></figure>

<figure><img src="image_20.png" /><figcaption>**Figure A1.** Line-spread function determination for Mg and Ca M2FS data. We restricted our line-spread function determination for the stars in our field with S/N ≥ 20.</figcaption></figure>

velocity dispersion measurements of 48 clusters. This more
than doubles the sample of reliable velocity dispersion
measurements, and represents measurements of nearly half of
all luminous GCs around Cen A.

To determine radii for these clusters, we updated the BP-RP Gaia excess factor and half-light radii relation from Voggel et al. (2020) using Gaia EDR3 (Riello et al. 2021). Gaia EDR3 is more complete than Gaia DR2 used in Voggel et al. (2020) and the BP-RP excess factor has been recalculated. This revised relation (Equation (2)) can be used to estimate half-mass radii for extragalactic GCs with sizes <1" to an accuracy of 14%.

We combine size measurements with the derived velocity
dispersions to determine virial masses and V-band mass-to-light
ratio for 57 luminous GCs. We find a bimodal distribution of
*M/L*<sub>V</sub> with a second population of elevated mass-to-light ratios
(*M/L*<sub>V</sub> > 2.3). Using a two component Gaussian mixture model
we find that 35% (20/57) of our luminous GC have inflated
*M/L*<sub>V</sub>.

Our preferred explanation for the elevated *M/L*<sub>V</sub> in these clusters is the presence of high mass fraction central black holes in the clusters. We create JAM dynamical models based on the integrated velocity dispersion to derive the central black hole mass needed to produce the elevated mass-to-light ratio. We find that black hole masses comprising 4%–18% of the luminous GC mass can explain the elevated mass-to-light ratios in these clusters. The maximum inferred BH mass is 8.61<sup>+10.3</sup><sub>-0.12</sub> × 10<sup>5</sup> *M*<sub>☉</sub> for the cluster VHH81-01. The possible presence of high mass fraction black holes supports the idea that some or even all of the 20 luminous GCs with elevated *M/L*<sub>V</sub> are the remnant nuclear star clusters of stripped galaxies. Future high spatial resolution kinematic observations will be able to verify directly if these clusters contain high mass fraction black holes.

Work by A.D. and A.C.S. has been supported by NSF AST-
1813609. AKH and DJS acknowledge support from NSF
grants AST-1821967 and 1813708. NC acknowledges support
by NSF grant AST-1812461. JS acknowledges support from
NSF grant AST-1812856 and the Packard Foundation. We

thank Christian I. Johnson for his recipe book for reducing
M2FS data. We also thank Paul Martini for providing the
MIKE spectroscopic data for 14 luminous GCs from his 2004
paper, and Pauline Barmby for globular cluster structural
properties from McLaughlin et al. (2008).

This paper made use of the the MGE fitting method and
software by Cappellari (2002) and JAM modeling method of
Cappellari (2008), as well as the astropy package (Astropy
Collaboration et al. 2013).

Facility: Magellan:Clay (LDSS2 imaging spectrograph).

Appendix
HST V-band Magnitudes

Figure A1 shows the derived FWHM of the stars used to measure the intrinsic LSF for the M2FS Magnesium Triplet and M2FS Calcium Triplet. The complete list of 321 luminous GCs candidates with their measured radial velocities and luminosity-weighted metallicities can be found in Table 2. The list of the 57 luminous GCs with measured velocity dispersions is presented in Table 3. Finally, the list of updated half-mass radii and mass-to-light ratios for 15 literature CenA's GCs are shown in Table 4. We found five objects (T17-1498, T17-1511, KV-280, KV19-289, T17-1614) where the magnitudes had large differences between their (very bright) NOAO DR2 values and (fainter) Gaia magnitudes (i.e., |g - G| > 2). PISCeS imaging cutouts for these objects show they are in crowded or star-forming regions that affect the ability to obtain reliable aperture photometry as is used for the NOAO catalog. Fortunately, all five objects had available HST F555W imaging—we obtained V-band magnitudes from the HST Legacy Archive SExtractor catalogs F555W SExtractor imaging photometry. Because F555W are Vega-based magnitudes, we assume they are equal to V-band magnitudes. (V − F555W = 0.02-0.4 based on old stellar populations from Marigo et al. 2017) models of 0.02-0.04 for old stellar populations). Additionally, three luminous GCs have g − r colors not consistent with the rest of our luminous GCs. KV19-273 and KV19-295 have very red colors, g − r > 1.1, and T17-1648 a very blue color of g − r ~ 0.1mag. PISCeS imaging cutouts for these objects show that two are in crowded regions and one is close to a
bright star. Only KV19-273 has available HST F555W imaging, and we were able to obtain V-band magnitude as described above. For KV19-295 and T17-1648 their bad g − r color affects our ability to estimate V-band magnitudes, and their V-band magnitudes may be wrong. Two more luminous GCs, *Fluffy* and *VHH81-5*, and a nuclear star cluster, ESO269-06, were not present in the Gaia EDR3 source catalog, and we estimated their sizes from fits to HST imaging data (see Section 4.1). To be consistent, we estimated their V-band magnitude from the same data assuming V-F606W ~ 0.25 based on expected colors for metal-poor old stellar populations using Padova Single Stellar Population (SSP) models (Marigo et al. 2017). Finally, we use the V-band magnitude of the nuclear star cluster of KK197-NSC from Georgiev et al. (2009). We correct for foreground extinction for these 10 sources using the same recipe as that for the NOAO DR2 photometry (see Section 2.1).

ORCID iDs

Antoine Dumont https://orcid.org/0000-0003-0234-3376

Anil C. Seth https://orcid.org/0000-0003-0248-5470

Jay Strader https://orcid.org/0000-0002-1468-9668

Karina Voggel https://orcid.org/0000-0001-6215-0950

David J. Sand https://orcid.org/0000-0003-4102-380X

Allison K. Hughes https://orcid.org/0000-0002-1718-0402

Nelson Caldwell https://orcid.org/0000-0003-2352-3202

Denija Crnojević https://orcid.org/0000-0002-1763-4128

John I. Bailey, III https://orcid.org/0000-0002-4272-263X

Duncan A. Forbes https://orcid.org/0000-0001-5590-5518

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