# Astrometric Membership Tests for the Zinn–Newell–Gibson
“UV-Bright” Stars in Galactic Globular Clusters

Howard E. Bond Department of Astronomy & Astrophysics, Pennsylvania State
University, University Park, PA 16802, USA  Space Telescope Science Institute,
3700 San Martin Drive, Baltimore, MD 21218, USA  Visiting Astronomer, Cerro
Tololo Inter-American Observatory and Kitt Peak National Observatory, National
Optical Astronomy Observatory, operated by the Association of Universities for
Research in Astronomy under a cooperative agreement with the National Science
Foundation.

###### Abstract

In 1972, Zinn, Newell, & Gibson (ZNG) published a list of 156 candidate “UV-
bright” stars they had found in 27 Galactic globular clusters (GCs), based on
photographs in the $U$ and $V$ bands. UV-bright stars lie above the horizontal
branch (HB) and blueward of the asymptotic-giant branch (AGB) and red-giant
branch in the clusters’ color-magnitude diagrams. They are in rapid
evolutionary phases—if they are members and not unrelated bright foreground
stars. The ZNG list has inspired numerous follow-up studies, aimed at
understanding late stages of stellar evolution. However, the ZNG candidates
were presented only in finding charts, and celestial coordinates were not
given. Using my own collection of CCD frames in $u$ and $V$, I have identified
all of the ZNG objects, and have assembled their coordinates, parallaxes, and
proper motions from the recent Gaia Early Data Release 3 (EDR3). Based on the
Gaia astrometry, I have determined which objects are probable cluster members
(45% of the sample). For the members, using photometry from EDR3, I have
assigned the stars to various evolutionary stages, including luminous post-AGB
stars, and stars above the HB. I point out several ZNG stars of special
interest that have still, to my knowledge, never been studied in detail. This
study is an adjunct to a forthcoming survey of the Galactic GCs in the uBVI
photometric system, designed for detection of low-gravity stars with large
Balmer discontinuities.

stars: AGB and post-AGB — globular clusters — stars: evolution — post-
horizontal-branch stellar evolution

††facilities: CTIO 0.9m, 1.5m; KPNO 0.9m, 4m; Gaia, Swift, HST

##  1 Stars Above the Horizontal Branch in Globular Clusters

In color-magnitude diagrams (CMDs) of globular clusters (GCs), the vast
majority of stars in post-main-sequence evolutionary stages lie on the
subgiant branch, red-giant branch (RGB), horizontal branch (HB), and
asymptotic-giant branch (AGB). There are, however, rare stars in transient
phases of rapid evolution that lie above the HB and to the blue of the AGB/RGB
in cluster CMDs. These objects include stars that have departed the HB and are
evolving toward the AGB, post-HB stars that reached the AGB but then left it
before arriving at the AGB tip (post-early-AGB, or PEAGB, stars), and objects
that reached the tip of the AGB and are now evolving rapidly toward higher
temperatures (post-AGB, or PAGB, stars). See Moehler et al. (2019, hereafter
M+19; their Figure 7) for examples of theoretical post-HB evolutionary tracks
that produce stars above the HB in GC CMDs. It is also possible that binary
interactions can generate stars lying above the HB.

Our group at Pennsylvania State University is conducting an observational
survey aimed at creating a complete census of above-horizontal-branch (AHB)
stars in the Galactic GC system. This survey is based on photometry in the
uBVI system (Bond, 2005), which is optimized for detection of low-gravity
evolved stars with large Balmer discontinuities in their spectral-energy
distributions. With astrometry from Gaia now available, including the recent
Early Data Release 3 (EDR3; Gaia Collaboration et al. 2020), we can further
test cluster membership using precise parallaxes and proper motions (PMs). Our
uBVI work led to discoveries of luminous “yellow” PAGB stars in M79 (Bond et
al., 2016, hereafter BCS16) and M19 (Bond et al., 2021, hereafter B+21). In
the case of M19, we also discovered a hotter, and equally luminous, blue PAGB
star belonging to the cluster. Full details of our uBVI survey for AHB stars
will be presented in a forthcoming paper (Davis et al., 2021, hereafter D+21).
Subsequent publications will explore the utility of yellow PAGB stars—which
are the visually brightest stars in old populations—as standard candles for
determining extragalactic distances, as I have advocated (Bond, 1997a, b).

##  2 The Zinn-Newell-Gibson “UV-Bright” Stars

The two luminous PAGB stars that B+21 found in M19 are among the brightest and
most conspicuous members known in any GC. In spite of this, they had not, to
our knowledge, been recognized as cluster members by previous investigators of
this massive GC. However, when we researched the literature, we found that
both of the M19 objects had been identified as “UV-bright” candidates in the
classical survey of Zinn et al. (1972, hereafter ZNG).

The ZNG team had blinked photographs of 27 GCs obtained in the $U$ and $V$
bands, and had identified 156 candidates that were the brightest objects in
the clusters in the $U$ band. The term “UV-bright” was a bit of a misnomer.
Many of the ZNG objects are indeed hot post-AGB stars, including the
prototypical luminous blue stars Barnard 29 in M13, and von Zeipel 1128 in M3.
However, many other ZNG candidates are even cooler than the yellow Type II
Cepheids in GCs, but nevertheless brighter than most of the cluster members in
the $U$ band—including objects that are actually unrelated bright foreground
stars.

ZNG presented finding charts for their candidates, but did not provide
celestial coordinates. There have been several follow-up studies of individual
ZNG objects (e.g., Zinn 1974; Harris et al. 1983; de Boer 1985; Jasniewicz et
al. 2004; Moehler 2001, 2010; M+19; and references therein), and several of
these stars have proven to be of great astrophysical interest. These include,
for example, several now well-known hot PAGB stars (see the lists in M+19).
However, there has never, to my knowledge, been a published list of the
celestial coordinates of all of the ZNG stars.

As an adjunct to the D+21 study, I determined the coordinates of all of the
ZNG stars, and I present them here. I then used astrometry from Gaia EDR3 to
test the cluster memberships of the candidates. Lastly, I give an indication
of the evolutionary status of the stars that appear to be cluster members,
based on their locations in the CMDs, and I point out several unstudied
objects of interest.

##  3 Identifying the ZNG Stars

I first identified each ZNG star in my uBVI CCD GC survey CCD images. These
frames had been obtained with 0.9-, 1.5-, and 4-m telescopes at Kitt Peak
National Observatory and Cerro Tololo Inter-American Observatory; they are
described in detail by B+21 and D+21. I blinked the $u$ and $V$ frames, while
comparing them with the ZNG finding charts. In nearly every case, the stars
were identified unambiguously; only a handful of objects near the cluster
centers were less certain. Approximate coordinates were then determined using
images from the Space Telescope Science Institute Digitized Sky
Survey,111https://archive.stsci.edu/cgi-bin/dss_form images from the
PanSTARRS-1 sky survey,222https://ps1images.stsci.edu/ and/or in a few cases
images from the Hubble Space Telescope.333https://hla.stsci.edu/hlaview.html
With all of these tools, coordinates can be obtained by placing a cursor on
the stellar images.

Finally, I identified each object in the Gaia EDR3
catalog.444https://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=I/350/gaiaedr3
Table 1 lists the 156 ZNG candidates, along with their J2000 coordinates, Gaia
parallaxes and PMs, and the Gaia apparent $G$ magnitudes and $BP-RP$ colors.
The notes to the table give information on the few instances of uncertain
identifications, as well as other information on the objects, but are not
intended to be a complete literature survey.

##  4 Cluster Membership Tests

Using the EDR3 astrometry, I tested each ZNG candidate for cluster membership.
Two criteria were applied to each star: PM and parallax; and in a few
instances a third one: radial velocity (RV). First, I determined the mean PMs
of each cluster in right ascension and declination and their dispersions,
based on a selection of cluster members from the EDR3 catalog; then I required
that each candidate have a PM consistent with that of the host cluster. In a
large majority of cases, the PM criterion alone was sufficient to exclude the
non-members. Next the parallax was considered. I adopted a nominal parallax
for each cluster, based on the reciprocals of the distances given in the
Harris (2010, hereafter H10) catalog of cluster parameters.555Online version
of 2010 December, at http://physwww.mcmaster.ca/~harris/mwgc.dat. Based on the
discussion in Gaia Collaboration et al. (2018), I used the H10 cluster
distances rather than distances based directly on Gaia parallaxes; in any
case, this choice makes little difference in the membership tests. The
parallax of each candidate was generally required to be consistent, within 3
times its stated uncertainty, with the nominal cluster parallax. There was,
however, a handful of cases where the star’s PM was in accord with membership,
but the parallax was larger (or occasionally smaller) than that of the
cluster, by more than the nominal 3 times the uncertainty. It is plausible
that their EDR3 parallaxes may have been affected by source crowding. These
ambiguous cases are discussed in the notes to Table 1. Finally, in a handful
of instances for the brightest objects, EDR3 also gives a radial velocity
(RV), another valuable membership criterion via comparison with the cluster’s
RV given in H10. The few cases where the Gaia RV helped confirm membership are
indicated in the notes to Table 1.

Figure 1 illustrates the PM and parallax membership tests, for the case of the
cluster M22. I selected stars from Gaia EDR3 lying within $5^{\prime}$ of the
cluster center, and brighter than $G$ magnitude 13. The PMs of these stars are
plotted as black and red points: black for stars with a parallax less than 0.6
mas (which is about twice the nominal cluster parallax), and red for the few
stars with a parallax of more than 0.6 mas (likely foreground stars). The EDR3
PMs are so precise that the cluster members form a tight distribution. The
small number of field stars and foreground objects have a much wider
dispersion and are offset from the cluster mean.

The larger filled circles in Figure 1 plot the PMs of 16 of the 18 ZNG
candidates. (Two of them have PMs so large they are outside the frame.) The
ZNG stars plotted in blue have parallaxes less than 0.6 mas, and the ones with
larger parallaxes are plotted in green. Four of the ZNG objects have PMs
consistent with cluster memberships, as well as small parallax values, making
them highly probable members. One of them, as noted in Table 1, also has a RV
consistent with membership. The remaining ZNG candidates in the figure have
PMs clearly inconsistent with that of the cluster, and most of them also have
parallaxes too large for cluster membership.666There is always a small
possibility of a field star happening to have a similar parallax and PM to
that of the cluster, especially in cases of a cluster with a small PM
superposed on a rich field; we will give a detailed and more formal discussion
of cluster-membership probability estimation in D+21.

Gaia EDR3 proper motions for stars lying within $5^{\prime}$ of the center of
the globular cluster M22. The small points plot stars brighter than $G=13$;
black points are for stars with a parallax less than 0.6 mas, and red points
for stars with larger parallaxes. The proper motions for 16 of the ZNG stars
are plotted as large filled circles, colored blue for parallaxes less than 0.6
mas, and green for larger parallaxes. Two of the ZNG candidates have large
proper motions placing them outside the frame. Four of the ZNG stars have both
proper motions and parallaxes consistent with cluster membership.

The final membership classifications are given in column 10 of Table 1, with a
question mark for the few ambiguous cases; these are discussed in the notes to
the table.

##  5 Evolutionary Status

For the ZNG candidates that I considered to be likely cluster members, I
estimated their evolutionary statuses based on their locations in the cluster
CMDs. The classification scheme that I adopted is based on cluster CMDs in
which the Gaia apparent magnitude $G$ is plotted against the color index $BP-
RP$. Figure 2 provides examples. Here the Gaia data are presented for three
ZNG GCs: M13, M53, and NGC 5897. Also included is M79, which is not one of the
ZNG clusters, but contains the luminous yellow PAGB star discovered by BCS16.
All four clusters are only lightly reddened [$E(B-V)=0.02$, 0.02, 0.09, and
0.01, respectively, from H10]. For each cluster, I selected a sample of likely
members from the EDR3 catalog, with parallaxes and PMs consistent with
membership.

Examples of a schematic classification scheme for stars above the horizontal
branch in globular clusters, based on color-magnitude diagrams plotting the
Gaia $G$ magnitude versus $BP-RP$ color. The black filled circles in each
frame show Gaia photometry for members of four lightly reddened clusters. The
members were selected on the basis of Gaia EDR3 parallaxes and proper motions.
The clusters’ horizontal branch (HB), red-giant branch (RGB), and asymptotic
giant branch (AGB) are labeled. The brightest stars are classified as post-AGB
stars with red (rPAGB), yellow (yPAGB), blue (bPAGB), and violet (vPAGB)
colors. Stars fainter than the PAGB sequence, down to within 0.5 mag of the HB
or AGB, are classified as AHB objects; these are stars evolving off the HB
toward cooler temperatures, along with stars leaving the AGB and evolving back
to hotter temperatures. The hottest and optically faintest objects at the
lower left are a combination of vPAGB stars and AGB-manqué stars. See the text
for further discussion of the scheme. The classification grid is shifted in
color and magnitude according to the reddening and distance of each cluster.
Upper left: M13. Filled colored circles mark the vPAGB star ZNG 1 = Barnard
29, and four AHB stars (ZNG 3, 4, 6, and 7). Upper right: M53. Filled colored
circles mark two AHB stars (ZNG 3 and 4), two stars on the RGB (ZNG 6 and 9),
three stars on the AGB (ZNG 7, 8, and 13), and one star on the HB (ZNG 16).
Lower left: NGC 5897. A filled colored circle marks the rPAGB star ZNG 2.
Lower right: M79. This cluster is not in the ZNG list, but is included to
illustrate its luminous yellow PAGB star, discovered by BCS16.

In each panel in Figure 2, the region of the CMD above the HB and to the blue
of the AGB is divided schematically into several boxes. These are based on
post-HB evolutionary tracks, such as those in M+19. The luminous PAGB sequence
is divided on the basis of color into red, yellow, blue, and violet
objects—rPAGB, yPAGB, bPAGB, and vPAGB, respectively. The rPAGB stars have
unreddened $BP-RP$ colors lying between 0.8 and up to within 0.1 mag of the
AGB, and $G$ magnitudes at least 3.5 mag brighter than that of the HB at $BP-
RP=0.8$. The yPAGB stars have $0<(BP-RP)<0.8$, and lie at least 3.5 mag
brighter than the HB at the same color. bPAGB objects are in the color range
$-0.25<(BP-RP)<0$, and are at least 3.5 mag brighter than the HB at the same
color. The hottest PAGB stars are those bluer than $BP-RP=-0.25$, and either
brighter than the brightness of the HB at a color of zero (vPAGB), or fainter
(vPAGB/AGB manqué). AGB-manqué objects evolve directly from the extremely blue
HB to the white-dwarf (WD) sequence, without ever becoming cool stars. As it
happens, however, the ZNG sample does not contain any such stars. These
divisions are somewhat arbitrary, but give a useful indication of the
approximate temperatures. The scheme should be considered preliminary, and
will be revised in our forthcoming paper (D+21).

Stars lying below the PAGB sequence, but at least 0.5 mag above the HB or AGB,
are called AHB objects. They are a mixture of stars evolving off of the blue
HB to cooler temperatures, along with PEAGB stars returning from the AGB
toward the top of the WD cooling sequence.

##  6 Results

Using the plotting tools at Vizier (see footnote 4) to generate CMDs derived
from Gaia EDR3 data for each GC, I applied the classification scheme described
above to all of the ZNG objects. The classification grid was shifted in color
and magnitude according to the reddening and distance of each cluster. The
classification results are given in column 11 of Table 1.

Out of the 156 candidates, 86 (55%) are non-members or likely non-members,
nearly all of them bright stars that clearly lie in the cluster foregrounds.
Although ZNG excluded stars known to be variable at the time of their survey,
the list contains several objects subsequently found to vary. These include
two Type II Cepheids and, more surprisingly, ten RR Lyrae variables. I
speculate that the latter were selected by ZNG because they happened to be
near maximum light at the epoch of the $U$-band exposures.

There are several cases of objects that are blends of two or more stars, which
would account for them appearing unusually bright in ground-based images. More
surprising is that there are quite a few candidates that appear to be
unexceptional stars lying on the RGB, AGB, or HB sequences. However, a few of
them are of interest because they are extremely bright, lying close to the
tips of the RGB or AGB. One of the most remarkable of these is NGC 6712 ZNG 4,
a very luminous star at the cluster’s AGB tip; it is the known Mira variable
AP Sct, which is NGC 6712 V2 in the Clement et al. (2001) catalog777Updated
version available online at
http://www.astro.utoronto.ca/~cclement/cat/listngc.html of variable stars in
GCs. One blue object, NGC 6093 (M80) ZNG 3, lies close to the position of a
known X-ray source, CX 3.

Among the bright PAGB stars, there are two red PAGB (rPAGB) objects: NGC 5897
ZNG 2 and NGC 6626 (M28) ZNG 5. The former star has not, to my knowledge, been
recognized previously as a luminous PAGB star; the latter is a known RV Tauri
variable, as described in the notes to Table 1. There is only one yellow PAGB
(yPAGB) star, the one in the cluster M19 that was recently pointed out for the
first time by B+21.

The table contains six luminous blue PAGB (bPAGB) and two violet PAGB (vPAGB)
stars. Of these, several are already well known (see M+19): NGC 5272 (M3) ZNG
1 (von Zeipel 1128), NGC 6205 (M13) ZNG 1 (Barnard 29), NGC 6254 (M10) ZNG 1,
NGC 6712 ZNG 1, and NGC 6779 (M56) ZNG 2. The bPAGB star NGC 6273 (M19) ZNG 2
was only noted for the first time in the recent B+21 study. NGC 6402 (M14) ZNG
1 was identified as a hot PAGB star based on GALEX imaging by Schiavon et al.
(2012), but has not otherwise been studied. The bPAGB object NGC 6333 (M9) ZNG
1 has not, to my knowledge, been recognized previously.

Lastly, Table 1 contains 27 AHB objects. As noted above, these are likely to
be a mixture of stars evolving off the hot HB toward the AGB, and stars that
reached the AGB and are now evolving back toward higher effective
temperatures. Like the PAGB stars, they are worth further study.

The ZNG survey was an important early observational investigation that added
to our understanding of late stellar evolution. Even after nearly five
decades, there are still unexplored objects of considerable interest in the
ZNG catalog. Our group’s uBVI survey, to be reported by B+21, will follow in
the path illuminated by this classical investigation.

I thank the Penn State “post-AGB group”— Robin Ciardullo, Brian Davis, and
Michael Siegel—for discussions of evolved stars in globular clusters. My uBVI
observations were partially supported by NASA grant NAG 5-6821 under the “UV,
Visible, and Gravitational Astrophysics Research and Analysis” program, and by
the Director’s Discretionary Research Fund at STScI. I also thank the staffs
at Cerro Tololo and Kitt Peak for their support over many years. This research
has made use of the VizieR catalogue access tool, CDS, Strasbourg, France
(DOI: 10.26093/cds/vizier). The original description of the VizieR service was
published by Ochsenbein et al. (2000). This work has made use of data from the
European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia),
processed by the Gaia Data Processing and Analysis Consortium (DPAC,
https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has
been provided by national institutions, in particular the institutions
participating in the Gaia Multilateral Agreement. The Digitized Sky Surveys
were produced at the Space Telescope Science Institute under U.S. Government
grant NAG W-2166. The images of these surveys are based on photographic data
obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK
Schmidt Telescope. The plates were processed into the present compressed
digital form with the permission of these institutions. The Pan-STARRS1
Surveys (PS1) and the PS1 public science archive have been made possible
through contributions by the Institute for Astronomy, the University of
Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its
participating institutes, the Max Planck Institute for Astronomy, Heidelberg
and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns
Hopkins University, Durham University, the University of Edinburgh, the
Queen’s University Belfast, the Harvard-Smithsonian Center for Astrophysics,
the Las Cumbres Observatory Global Telescope Network Incorporated, the
National Central University of Taiwan, the Space Telescope Science Institute,
the National Aeronautics and Space Administration under Grant No. NNX08AR22G
issued through the Planetary Science Division of the NASA Science Mission
Directorate, the National Science Foundation Grant No. AST-1238877, the
University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos
National Laboratory, and the Gordon and Betty Moore Foundation. Based in part
on observations made with the NASA/ESA Hubble Space Telescope, obtained from
the data archive at the Space Telescope Science Institute. STScI is operated
by the Association of Universities for Research in Astronomy, Inc. under NASA
contract NAS 5-26555.

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Table 1: The ZNG UV-Bright Candidates and Gaia Astrometry and Photometry  Cluster | ZNG | RA | Dec | Parallax | $\mu_{\alpha}$ | $\mu_{\delta}$ | $G$ | $BP-RP$ | Cluster | Classi- | Remarkscc Remarks: [1] 4147 ZNG 2: HST images show object to be blend of 5 cluster members of similar brightness; brightest one listed. [2] 4590 ZNG 2: At tip of AGB/RGB; see Schaeuble et al. (2015) and references therein. [3] 5024 ZNG 3: considered a non-member by Boberg et al. (2016). [4] 5024 ZNG 7: Close nearly equal pair, separation 0”.9. Astrometry has large uncertainties, but both components consistent with membership. Brighter component listed. Non-member according to Boberg et al. (2016). [5] 5024 ZNG 8: Astrometry has large uncertainties. Member according to Boberg et al. (2016). [6] 5024 ZNG 9: Member according to Boberg et al. (2016). Blended with a fainter AGB star $2\farcs 0$ away. [7] 5024 ZNG 14: Identification uncertain. Astrometry has large uncertainties, but membership unlikely. [8] 5272 ZNG 1: M3 von Zeipel 1128. [9] 5272 ZNG 3: RR Lyr variable V10. [10] 5272 ZNG 4: Blend of 3 stars; bluest one listed. RR Lyr variable V165. [11] 5272 ZNG 5: RR Lyr variable V90. [12] 5466 ZNG 5: Extreme HB star; see Geier et al. (2019). [13] 5466 ZNG 6: AGB star; see Shetrone et al. (2010). [14] 5897 ZNG 2: Luminous red post-AGB star. Gaia RV consistent with membership. [15] 5904 ZNG 1: Known hot vPAGB star (e.g., Dixon et al. 2004), not contained in EDR3 because of neighboring ($0\farcs 52$) bright red giant; position obtained from HST images. [16] 5904 ZNG 2: Proper motion consistent with membership, parallax discordant; AGB or RGB tip star if member. [17] 5904 ZNG 6: RR Lyr variable V41. [18] 5904 ZNG 7: RR Lyr variable V25. [19] 6093 ZNG 1: Proper motion consistent with membership, parallax discordant; RGB star if member. [20] 6093 ZNG 3: EDR3 does not give a parallax or proper motion for this source; there is a bright blue object at this position in HST images, but the Gaia $BP-RP$ color is red. Position is close to that of the X-ray source CX3 (Heinke et al., 2003). [21] 6121 ZNG 2: RR Lyr variable V19. [22] 6121 ZNG 4: RR Lyr variable V10. [23] 6121 ZNG 5: This object is a blend of two RR Lyr variables, separated by $1\farcs 6$ (Clementini et al., 2019). Brighter component is listed in table. [24] 6121 ZNG 6: Candidate RR Lyr, V58, but non-variable according to Safonova et al. (2016). [25] 6121 ZNG 7: Very bright star at tip of RGB. Gaia RV consistent with membership. [26] 6121 ZNG 9: RR Lyr variable V28. [27] 6205 ZNG 1: Barnard 29 (see M+19). [28] 6205 ZNG 2: Proper motion consistent with membership, but large uncertainties and discordant parallax; suspected low-amplitude variable (Deras et al., 2019). [29] 6205 ZNG 3: Variable star V51, uncertain type (Servillat et al., 2011). [30] 6205 ZNG 4: Spectroscopic analysis by Ambika et al. (2004). [31] 6218 ZNG 7: Gaia RV consistent with membership. [32] 6218 ZNG 8: Gaia RV consistent with membership. [33] 6254 ZNG 1: Blue PAGB star (see M+19). [34] 6273 ZNG 2: Blue PAGB star (see B+21). [35] 6273 ZNG 3: Type II Cepheid, V1 (Clement & Sawyer Hogg, 1978); proper motion consistent with membership, parallax discordant. [36] 6273 ZNG 4: Yellow PAGB star (see B+21). [37] 6333 ZNG 1: Proper motion consistent with membership; parallax slightly discrepant. On boundary between yellow and blue PAGB stars. [38] 6333 ZNG 4: Astrometry consistent with membership, but uncertainties are large. [39] 6341 ZNG 4: Proper motion consistent with membership, but parallax is discordant. Considered a member by Zinn (1974), but not by Roederer & Sneden (2011). [40] 6356 ZNG 2: Proper motion marginally consistent with membership. [41] 6402 ZNG 1: Blue PAGB star (star 33 in Schiavon et al. 2012). [42] 6402 ZNG 5: Above HB (star 202 in Schiavon et al. 2012). [43] 6402 ZNG 14: Type II Cepheid, V167 (Contreras Peña et al., 2018). [44] 6626 ZNG 5: RV Tauri variable V2342 Sgr = V17. [45] 6656 ZNG 14: Gaia RV consistent with membership. [46] 6712 ZNG 1: Blue PAGB star (see M+19). [47] 6712 ZNG 4: Luminous star at AGB tip; Mira variable AP Sct = V2. [48] 6779 ZNG 2: Violet PAGB star (see M+19). [49] 7078 ZNG 1: Hot post-HB or violet PAGB star (see M+19). [50] 7078 ZNG 4: Identification difficult and uncertain. Listed star is brighter of close $1\farcs 4$ pair. [51] 7078 ZNG 5: Identification difficult and uncertain. Listed star is brighter of close $1\farcs 4$ pair. [52] 7078 ZNG 6: Proper motion consistent with membership, but parallax is discordant. If it is a member, it is a bright star near the AGB tip. [53] 7078 ZNG 7: Astrometry has large uncertainties; Gebhardt et al. (1997) give a radial velocity consistent with membership.
---|---|---|---|---|---|---|---|---|---|---|---
NGC/M | No. | [J2000] | [J2000] | [mas] | [$\rm mas\,yr^{-1}$] | [$\rm mas\,yr^{-1}$] | [mag] | [mag] | Member?aaIndication of cluster membership, based on parallax and proper motion. A few uncertain cases are labeled with question marks. | ficationbbEvolutionary classification scheme is explained in text (§6) and Figure 2 caption; based on position in Gaia color-magnitude diagrams. Abbreviations are: AGB (asymptotic-giant branch); RGB (red-giant branch); HB (horizontal branch); rPAGB, yPAGB, bPAGB, and vPAGB (red, yellow, blue, and violet post-AGB stars); AHB (above horizontal branch); and CV (cataclysmic variable). |
2419 | 1 | 07 38 11.156 |  $+38$ 52 27.74 | $0.5929\pm 0.0633$ | $4.740\pm 0.057$ | $-8.559\pm 0.036$ | 16.318 | $0.987$ | no |  |
| 2 | 07 38 09.234 |  $+38$ 53 12.77 | $0.2301\pm 0.1527$ | $-0.257\pm 0.135$ | $-0.414\pm 0.090$ | 17.395 | $0.305$ | yes | AHB |
4147 | 1 | 12 09 58.479 |  $+18$ 34 08.78 | $1.0151\pm 0.0248$ | $-20.213\pm 0.026$ | $-8.615\pm 0.023$ | 14.326 | $0.823$ | no |  |
| 2 | 12 10 05.661 |  $+18$ 32 45.69 | $0.1253\pm 0.1069$ | $-1.858\pm 0.105$ | $-2.430\pm 0.099$ | 16.856 | $0.250$ | yes | HB | -52
4590/ | 1 | 12 39 40.099 |  $-26$ 43 02.62 | $0.3911\pm 0.0289$ | $-11.104\pm 0.030$ | $-5.431\pm 0.021$ | 14.300 | $0.498$ | no |  |
M68 | 2 | 12 39 22.513 |  $-26$ 45 11.87 | $0.0916\pm 0.0160$ | $-2.792\pm 0.016$ | $1.943\pm 0.012$ | 12.258 | $1.451$ | yes | AGB | -51
5024/ | 1 | 13 12 56.879 |  $+18$ 10 53.17 | $4.6060\pm 0.0146$ | $-78.011\pm 0.019$ | $-29.825\pm 0.016$ | 12.388 | $1.013$ | no |  |
M53 | 2 | 13 12 47.541 |  $+18$ 10 23.15 | $1.1056\pm 0.0206$ | $-17.135\pm 0.026$ | $-4.531\pm 0.024$ | 14.395 | $0.903$ | no |  |
| 3 | 13 12 45.206 |  $+18$ 11 57.44 | $0.0211\pm 0.0269$ | $-0.165\pm 0.036$ | $-1.351\pm 0.033$ | 14.850 | $0.192$ | yes | AHB | -50
| 4 | 13 12 47.406 |  $+18$ 07 10.77 | $0.0519\pm 0.0505$ | $-0.401\pm 0.065$ | $-1.422\pm 0.062$ | 15.701 | $0.297$ | yes | AHB |
| 5 | 13 13 09.478 |  $+18$ 10 58.70 | $0.9811\pm 0.0241$ | $-15.057\pm 0.032$ | $-24.435\pm 0.031$ | 14.741 | $0.770$ | no |  |
| 6 | 13 13 11.459 |  $+18$ 08 09.47 | $0.0533\pm 0.0361$ | $-0.080\pm 0.049$ | $-1.297\pm 0.047$ | 15.734 | $1.136$ | yes | RGB |
| 7 | 13 12 48.140 |  $+18$ 09 45.71 | $-0.3570\pm 0.0836$ | $-0.588\pm 0.100$ | $-0.379\pm 0.100$ | 15.129 | $1.133$ | yes? | AGB | -49
| 8 | 13 13 02.930 |  $+18$ 11 06.60 | $-0.2584\pm 0.0964$ | $-0.627\pm 0.124$ | $-0.644\pm 0.125$ | 14.015 | $1.332$ | yes | AGB | -48
| 9 | 13 13 03.347 |  $+18$ 11 43.51 | $0.0281\pm 0.0225$ | $-0.096\pm 0.030$ | $-1.392\pm 0.029$ | 14.613 | $1.292$ | yes | RGB | -47
| 10 | 13 13 11.209 |  $+18$ 13 08.27 | $1.0669\pm 0.0238$ | $0.680\pm 0.032$ | $-21.557\pm 0.031$ | 14.764 | $0.808$ | no |  |
| 11 | 13 12 29.048 |  $+18$ 07 16.08 | $1.3456\pm 0.0185$ | $-8.315\pm 0.024$ | $10.187\pm 0.025$ | 14.137 | $0.776$ | no |  |
| 12 | 13 13 22.626 |  $+18$ 10 09.39 | $1.0159\pm 0.0362$ | $2.877\pm 0.048$ | $-10.336\pm 0.048$ | 14.872 | $0.842$ | no |  |
| 13 | 13 12 57.021 |  $+18$ 10 34.92 | $-0.1280\pm 0.0818$ | $-0.573\pm 0.105$ | $-1.402\pm 0.100$ | 14.309 | $1.177$ | yes | AGB |
| 14 | 13 12 54.119 |  $+18$ 09 56.99 | $0.3272\pm 0.2388$ | $1.954\pm 0.319$ | $-4.473\pm 0.376$ | 13.968 | $1.111$ | no? |  | -46
| 15 | 13 12 58.238 |  $+18$ 08 36.84 | $2.7637\pm 0.2488$ | $3.468\pm 0.323$ | $-0.208\pm 0.313$ | 15.881 | $0.802$ | no |  |
| 16 | 13 12 54.235 |  $+18$ 11 47.54 | $-0.0415\pm 0.0832$ | $-0.122\pm 0.111$ | $-1.451\pm 0.101$ | 16.995 | $0.197$ | yes | HB |
5053 | 1 | 13 16 39.651 |  $+17$ 41 39.43 | $1.5468\pm 0.0237$ | $-7.021\pm 0.025$ | $4.437\pm 0.026$ | 14.461 | $0.923$ | no |  |
| 2 | 13 16 08.506 |  $+17$ 41 43.35 | $1.1008\pm 0.0251$ | $-13.801\pm 0.029$ | $-8.455\pm 0.027$ | 14.411 | $0.821$ | no |  |
5272/ | 1 | 13 42 16.750 |  $+28$ 26 00.61 | $0.0387\pm 0.0413$ | $-0.241\pm 0.050$ | $-2.716\pm 0.028$ | 14.947 | $-0.442$ | yes | vPAGB | -45
M3 | 2 | 13 42 10.767 |  $+28$ 19 05.32 | $1.9252\pm 0.0153$ | $-10.787\pm 0.018$ | $5.088\pm 0.010$ | 13.343 | $0.859$ | no |  |
| 3 | 13 42 23.099 |  $+28$ 25 00.53 | $0.0417\pm 0.0415$ | $-0.115\pm 0.045$ | $-2.521\pm 0.025$ | 15.621 | $0.637$ | yes | HB | -44
| 4 | 13 42 17.042 |  $+28$ 23 02.81 | $0.0561\pm 0.1787$ | $-0.243\pm 0.192$ | $-1.689\pm 0.118$ | 15.616 | $0.669$ | yes | HB | -43
| 5 | 13 42 18.924 |  $+28$ 19 34.11 | $0.0615\pm 0.0368$ | $-0.291\pm 0.042$ | $-2.495\pm 0.024$ | 15.657 | $0.551$ | yes | HB | -42
| 6 | 13 41 51.504 |  $+28$ 17 44.54 | $0.7638\pm 0.0203$ | $-13.185\pm 0.022$ | $-4.738\pm 0.012$ | 13.931 | $0.813$ | no |  |
5466 | 1 | 14 05 10.675 |  $+28$ 28 54.23 | $0.6579\pm 0.0257$ | $7.710\pm 0.027$ | $-13.591\pm 0.022$ | 13.861 | $0.592$ | no |  |
| 2 | 14 05 15.075 |  $+28$ 26 52.20 | $1.4961\pm 0.0184$ | $19.140\pm 0.019$ | $-17.784\pm 0.016$ | 13.987 | $0.874$ | no |  |
| 3 | 14 05 16.967 |  $+28$ 25 46.55 | $1.1790\pm 0.0158$ | $-4.106\pm 0.017$ | $-6.210\pm 0.014$ | 13.867 | $0.719$ | no |  |
| 4 | 14 05 38.767 |  $+28$ 33 00.05 | $0.1491\pm 0.0185$ | $0.447\pm 0.020$ | $-11.631\pm 0.017$ | 14.060 | $0.818$ | no |  |
| 5 | 14 05 41.566 |  $+28$ 34 37.32 | $-0.1447\pm 0.0802$ | $-5.302\pm 0.093$ | $-0.753\pm 0.075$ | 17.410 | $-0.144$ | yes | HB | -41
| 6 | 14 05 29.091 |  $+28$ 32 47.23 | $0.0124\pm 0.0176$ | $-5.360\pm 0.019$ | $-0.868\pm 0.016$ | 14.188 | $1.139$ | yes | AGB | -40
5634 | 1 | 14 29 36.219 |  $-05$ 58 16.76 | $0.2767\pm 0.0423$ | $0.074\pm 0.053$ | $-26.117\pm 0.042$ | 15.650 | $0.762$ | no |  |
| 2 | 14 29 33.211 |  $-05$ 57 45.36 | $0.5259\pm 0.0181$ | $-19.371\pm 0.023$ | $-21.113\pm 0.019$ | 14.080 | $1.030$ | no |  |
| 3 | 14 29 29.487 |  $-05$ 58 44.27 | $0.9716\pm 0.0202$ | $-3.394\pm 0.026$ | $-9.159\pm 0.021$ | 13.988 | $0.828$ | no |  |
5897 | 1 | 15 17 17.592 |  $-21$ 03 18.75 | $0.2510\pm 0.0173$ | $-4.685\pm 0.017$ | $-7.882\pm 0.014$ | 13.330 | $0.961$ | no |  |
| 2 | 15 17 30.443 |  $-21$ 00 10.37 | $0.1025\pm 0.0178$ | $-5.433\pm 0.017$ | $-3.241\pm 0.016$ | 12.672 | $1.378$ | yes | rPAGB | -39
5904/ | 1 | 15 18 34.101 |  $+02$ 04 59.76 | $\dots$ | $\dots$ | $\dots$ | $\dots$ | $\dots$ | yes | vPAGB | -38
M5 | 2 | 15 18 35.690 |  $+02$ 03 46.11 | $-0.1568\pm 0.0394$ | $4.195\pm 0.049$ | $-9.910\pm 0.038$ | 11.562 | $1.705$ | no? |  | -37
| 3 | 15 18 17.349 |  $+02$ 02 29.55 | $1.4686\pm 0.0485$ | $-7.348\pm 0.054$ | $-2.279\pm 0.054$ | 13.317 | $0.874$ | no |  |
| 4 | 15 18 48.160 |  $+02$ 02 16.81 | $1.5443\pm 0.0181$ | $-23.625\pm 0.019$ | $17.194\pm 0.021$ | 13.422 | $0.846$ | no |  |
| 5 | 15 18 45.927 |  $+02$ 04 14.90 | $1.0363\pm 0.0226$ | $-17.570\pm 0.024$ | $-1.869\pm 0.024$ | 13.776 | $0.811$ | no |  |
| 6 | 15 18 35.026 |  $+02$ 08 40.09 | $0.0479\pm 0.0338$ | $4.147\pm 0.031$ | $-9.885\pm 0.031$ | 15.123 | $0.617$ | yes | HB | -36
| 7 | 15 18 31.070 |  $+02$ 02 42.76 | $-0.1631\pm 0.1482$ | $3.869\pm 0.132$ | $-9.659\pm 0.129$ | 14.574 | $0.879$ | yes | HB | -35
6093/ | 1 | 16 17 04.351 |  $-22$ 59 11.72 | $0.2111\pm 0.0280$ | $-2.942\pm 0.034$ | $-5.821\pm 0.029$ | 13.660 | $1.573$ | no? |  | -34
M80 | 2 | 16 17 15.936 |  $-22$ 58 28.32 | $1.7916\pm 0.0194$ | $-3.290\pm 0.027$ | $-1.695\pm 0.021$ | 13.826 | $0.982$ | no |  |
| 3 | 16 17 01.555 |  $-22$ 58 30.68 | $\dots$ | $\dots$ | $\dots$ | 15.216 | $1.313$ | yes? | CV? | -33
| 4 | 16 17 11.479 |  $-23$ 01 57.38 | $1.8891\pm 0.1118$ | $-13.539\pm 0.131$ | $-13.728\pm 0.100$ | 13.842 | $1.131$ | no |  |
| 5 | 16 17 08.152 |  $-22$ 56 32.05 | $2.1391\pm 0.0187$ | $-12.222\pm 0.024$ | $-14.064\pm 0.020$ | 12.124 | $0.898$ | no |  |
6121/ | 1 | 16 23 32.449 |  $-26$ 26 45.86 | $5.0588\pm 0.0206$ | $5.387\pm 0.026$ | $-8.654\pm 0.019$ | 11.182 | $1.128$ | no |  |
M4 | 2 | 16 23 35.031 |  $-26$ 25 36.49 | $0.5575\pm 0.0189$ | $-13.069\pm 0.024$ | $-18.276\pm 0.018$ | 13.183 | $1.087$ | yes | HB | -32
| 3 | 16 23 39.404 |  $-26$ 34 54.53 | $4.7764\pm 0.0205$ | $17.849\pm 0.025$ | $-15.673\pm 0.018$ | 10.103 | $1.189$ | no |  |
| 4 | 16 23 29.185 |  $-26$ 28 54.38 | $0.5858\pm 0.0205$ | $-12.286\pm 0.025$ | $-18.590\pm 0.018$ | 13.161 | $1.095$ | yes | HB | -31
| 5 | 16 23 36.469 |  $-26$ 30 44.33 | $0.6220\pm 0.0239$ | $-11.733\pm 0.029$ | $-20.013\pm 0.022$ | 12.894 | $0.992$ | yes | HB | -30
| 6 | 16 23 47.824 |  $-26$ 32 05.99 | $0.5006\pm 0.0165$ | $-12.794\pm 0.022$ | $-20.022\pm 0.016$ | 13.395 | $0.605$ | yes | HB | -29
| 7 | 16 23 48.797 |  $-26$ 35 09.17 | $0.5526\pm 0.0467$ | $-11.702\pm 0.059$ | $-18.739\pm 0.036$ | 11.026 | $1.888$ | yes | RGB | -28
| 8 | 16 23 50.103 |  $-26$ 36 09.55 | $0.5132\pm 0.0188$ | $-12.461\pm 0.022$ | $-18.989\pm 0.017$ | 12.894 | $0.731$ | yes | HB |
| 9 | 16 23 53.591 |  $-26$ 30 05.35 | $0.5757\pm 0.0221$ | $-12.615\pm 0.028$ | $-19.512\pm 0.021$ | 12.946 | $1.016$ | yes | HB | -27
6205/ | 1 | 16 41 33.666 |  $+36$ 26 07.78 | $0.0775\pm 0.0298$ | $-3.203\pm 0.031$ | $-2.760\pm 0.033$ | 13.123 | $-0.255$ | yes | vPAGB | -26
M13 | 2 | 16 41 34.759 |  $+36$ 29 13.89 | $2.0187\pm 0.4059$ | $-3.190\pm 0.411$ | $-3.180\pm 0.464$ | 14.270 | $0.267$ | yes? | AHB | -25
| 3 | 16 41 52.090 |  $+36$ 26 28.90 | $0.0934\pm 0.0164$ | $-3.137\pm 0.015$ | $-2.712\pm 0.018$ | 14.089 | $0.182$ | yes | AHB | -24
| 4 | 16 41 36.437 |  $+36$ 30 51.67 | $0.1158\pm 0.0174$ | $-3.229\pm 0.017$ | $-2.572\pm 0.021$ | 14.055 | $0.206$ | yes | AHB | -23
| 5 | 16 41 19.580 |  $+36$ 21 15.62 | $0.2542\pm 0.0146$ | $-4.672\pm 0.015$ | $-1.707\pm 0.019$ | 11.380 | $1.442$ | no |  |
| 6 | 16 41 43.018 |  $+36$ 28 42.20 | $0.0894\pm 0.0228$ | $-3.397\pm 0.021$ | $-2.414\pm 0.027$ | 14.646 | $0.014$ | yes | AHB |
| 7 | 16 41 08.024 |  $+36$ 30 05.38 | $0.0878\pm 0.0250$ | $-3.287\pm 0.025$ | $-2.469\pm 0.034$ | 15.361 | $-0.185$ | yes | AHB |
6218/ | 1 | 16 47 18.547 |  $-02$ 00 10.86 | $1.8183\pm 0.0132$ | $-57.328\pm 0.014$ | $-89.440\pm 0.012$ | 12.326 | $1.005$ | no |  |
M12 | 2 | 16 47 00.790 |  $-01$ 58 28.25 | $0.3748\pm 0.0137$ | $-9.177\pm 0.015$ | $-21.670\pm 0.013$ | 12.587 | $1.294$ | no |  |
| 3 | 16 47 12.136 |  $-01$ 54 06.92 | $1.2808\pm 0.0132$ | $-2.300\pm 0.015$ | $8.715\pm 0.012$ | 11.926 | $1.300$ | no |  |
| 4 | 16 47 08.603 |  $-02$ 01 37.07 | $0.4723\pm 0.0123$ | $-1.061\pm 0.014$ | $-4.560\pm 0.011$ | 12.479 | $1.338$ | no |  |
| 5 | 16 47 45.287 |  $-01$ 55 03.50 | $0.7490\pm 0.0136$ | $-7.806\pm 0.015$ | $-6.641\pm 0.012$ | 13.183 | $0.915$ | no |  |
| 6 | 16 47 27.241 |  $-01$ 52 19.49 | $1.2837\pm 0.0151$ | $6.753\pm 0.019$ | $-8.277\pm 0.015$ | 13.590 | $0.921$ | no |  |
| 7 | 16 47 18.056 |  $-01$ 58 17.40 | $0.1382\pm 0.0135$ | $-0.358\pm 0.015$ | $-6.911\pm 0.013$ | 12.690 | $1.401$ | yes | AGB | -22
| 8 | 16 47 25.974 |  $-02$ 01 03.39 | $0.1799\pm 0.0119$ | $-0.187\pm 0.013$ | $-6.882\pm 0.010$ | 12.136 | $1.435$ | yes | AGB | -21
| 9 | 16 47 39.628 |  $-02$ 01 25.49 | $1.7309\pm 0.0176$ | $15.382\pm 0.020$ | $-1.958\pm 0.016$ | 13.089 | $0.876$ | no |  |
6254/ | 1 | 16 57 09.253 |  $-04$ 04 24.40 | $0.1131\pm 0.0230$ | $-4.844\pm 0.025$ | $-6.795\pm 0.019$ | 13.485 | $0.016$ | yes | bPAGB | -20
M10 | 2 | 16 57 09.836 |  $-04$ 04 28.50 | $0.1663\pm 0.0205$ | $-4.342\pm 0.023$ | $-6.248\pm 0.017$ | 13.729 | $0.354$ | yes | AHB |
| 3 | 16 57 18.697 |  $-04$ 09 06.82 | $0.9588\pm 0.0262$ | $0.859\pm 0.027$ | $-5.637\pm 0.020$ | 11.152 | $1.434$ | no |  |
| 4 | 16 57 10.387 |  $-04$ 04 01.74 | $0.1697\pm 0.0170$ | $-4.934\pm 0.018$ | $-6.616\pm 0.014$ | 13.026 | $1.525$ | yes | RGB |
| 5 | 16 57 05.571 |  $-04$ 06 52.31 | $0.2817\pm 0.0335$ | $-4.618\pm 0.035$ | $-6.585\pm 0.029$ | 13.998 | $0.426$ | yes | AHB |
| 6 | 16 57 06.332 |  $-04$ 07 17.03 | $0.1471\pm 0.0734$ | $-4.279\pm 0.082$ | $-6.317\pm 0.069$ | 13.940 | $0.741$ | yes | AHB |
| 7 | 16 57 12.231 |  $-04$ 11 26.97 | $1.7263\pm 0.0232$ | $-0.705\pm 0.024$ | $2.203\pm 0.019$ | 11.398 | $1.392$ | no |  |
| 8 | 16 56 57.629 |  $-04$ 07 16.03 | $0.2181\pm 0.0229$ | $-4.786\pm 0.024$ | $-6.737\pm 0.018$ | 14.248 | $0.376$ | yes | AHB |
6273/ | 1 | 17 02 41.532 |  $-26$ 15 16.42 | $0.9908\pm 0.0165$ | $-1.240\pm 0.018$ | $-2.328\pm 0.012$ | 12.083 | $0.526$ | no |  |
M19 | 2 | 17 02 39.154 |  $-26$ 15 29.36 | $0.1582\pm 0.0236$ | $-2.990\pm 0.025$ | $1.454\pm 0.018$ | 13.207 | $0.518$ | yes | bPAGB | -19
| 3 | 17 02 38.139 |  $-26$ 15 11.75 | $0.3344\pm 0.0409$ | $-3.034\pm 0.048$ | $1.946\pm 0.033$ | 13.342 | $1.404$ | yes? | AHB | -18
| 4 | 17 02 35.185 |  $-26$ 15 24.13 | $0.1177\pm 0.0157$ | $-2.878\pm 0.019$ | $1.146\pm 0.012$ | 12.204 | $1.238$ | yes | yPAGB | -17
| 5 | 17 02 24.171 |  $-26$ 14 40.71 | $1.8255\pm 0.0176$ | $-4.142\pm 0.019$ | $-2.644\pm 0.013$ | 12.718 | $0.931$ | no |  |
| 6 | 17 02 26.447 |  $-26$ 16 08.28 | $1.2297\pm 0.4424$ | $-3.274\pm 0.508$ | $-10.004\pm 0.353$ | 13.570 | $1.285$ | no |  |
6333/ | 1 | 17 19 15.461 |  $-18$ 31 10.71 | $0.0697\pm 0.0183$ | $-2.326\pm 0.020$ | $-3.390\pm 0.014$ | 12.836 | $0.561$ | yes? | bPAGB | -16
M9 | 2 | 17 19 05.776 |  $-18$ 32 53.32 | $0.3581\pm 0.0150$ | $6.749\pm 0.018$ | $-14.170\pm 0.012$ | 13.187 | $0.569$ | no |  |
| 3 | 17 19 03.581 |  $-18$ 30 43.67 | $2.5533\pm 0.0162$ | $0.193\pm 0.019$ | $-0.128\pm 0.012$ | 13.308 | $1.147$ | no |  |
| 4 | 17 19 05.924 |  $-18$ 31 33.16 | $0.3946\pm 0.1833$ | $-2.197\pm 0.212$ | $-4.114\pm 0.137$ | 14.480 | $0.787$ | yes? | AHB | -15
6341/ | 1 | 17 16 56.770 |  $+43$ 05 36.82 | $2.0357\pm 0.0127$ | $5.480\pm 0.015$ | $-2.531\pm 0.015$ | 11.670 | $0.576$ | no |  |
M92 | 2 | 17 17 03.850 |  $+43$ 05 50.45 | $4.9922\pm 0.0386$ | $-56.771\pm 0.046$ | $-63.174\pm 0.047$ | 12.679 | $1.085$ | no |  |
| 3 | 17 16 58.376 |  $+43$ 01 18.04 | $1.0549\pm 0.0130$ | $-8.175\pm 0.016$ | $0.250\pm 0.016$ | 12.953 | $0.775$ | no |  |
| 4 | 17 16 29.018 |  $+43$ 09 43.80 | $0.2461\pm 0.0105$ | $-4.061\pm 0.013$ | $-1.535\pm 0.012$ | 13.328 | $0.943$ | no |  | -14
6356 | 1 | 17 23 32.455 |  $-17$ 49 38.41 | $1.1879\pm 0.0297$ | $2.353\pm 0.030$ | $-6.151\pm 0.020$ | 14.380 | $1.101$ | no |  |
| 2 | 17 23 29.547 |  $-17$ 49 10.62 | $0.0568\pm 0.0294$ | $1.815\pm 0.036$ | $-3.089\pm 0.021$ | 14.265 | $1.482$ | yes? | AHB | -13
| 3 | 17 23 40.827 |  $-17$ 49 24.47 | $0.4388\pm 0.1070$ | $-4.023\pm 0.099$ | $1.345\pm 0.074$ | 14.820 | $1.295$ | no |  |
6402/ | 1 | 17 37 33.178 |  $-03$ 14 51.68 | $0.0748\pm 0.0368$ | $-3.803\pm 0.034$ | $-5.178\pm 0.026$ | 14.538 | $0.863$ | yes | bPAGB | -12
M14 | 2 | 17 37 33.434 |  $-03$ 16 09.89 | $1.3874\pm 0.0193$ | $-4.388\pm 0.019$ | $5.385\pm 0.014$ | 13.217 | $1.356$ | no |  |
| 3 | 17 37 44.596 |  $-03$ 11 50.37 | $0.5030\pm 0.0229$ | $4.054\pm 0.022$ | $-1.104\pm 0.017$ | 13.696 | $1.000$ | no |  |
| 4 | 17 37 48.410 |  $-03$ 15 47.78 | $2.2708\pm 0.0663$ | $0.130\pm 0.063$ | $-10.114\pm 0.050$ | 13.446 | $1.482$ | no |  |
| 5 | 17 37 30.986 |  $-03$ 15 03.77 | $0.1841\pm 0.0449$ | $-3.501\pm 0.043$ | $-5.080\pm 0.033$ | 15.257 | $0.842$ | yes | AHB | -11
| 6 | 17 37 33.749 |  $-03$ 15 42.09 | $-0.0981\pm 0.0531$ | $-3.659\pm 0.051$ | $-4.962\pm 0.039$ | 14.642 | $1.128$ | yes | AHB |
| 7 | 17 37 31.877 |  $-03$ 14 52.47 | $-0.0424\pm 0.0385$ | $-3.687\pm 0.037$ | $-5.033\pm 0.029$ | 15.353 | $0.966$ | yes | AHB |
| 8 | 17 37 21.521 |  $-03$ 15 18.01 | $1.1383\pm 0.1176$ | $4.360\pm 0.094$ | $0.377\pm 0.074$ | 14.727 | $1.345$ | no |  |
| 9 | 17 37 27.238 |  $-03$ 12 56.63 | $1.3406\pm 0.0259$ | $1.469\pm 0.024$ | $10.036\pm 0.019$ | 14.759 | $1.510$ | no |  |
| 10 | 17 37 35.767 |  $-03$ 16 29.98 | $0.1324\pm 0.0385$ | $-3.612\pm 0.035$ | $-4.943\pm 0.028$ | 15.569 | $0.916$ | yes | AHB |
| 11 | 17 37 48.235 |  $-03$ 15 52.97 | $2.0882\pm 0.0188$ | $0.019\pm 0.018$ | $-10.942\pm 0.014$ | 13.862 | $1.458$ | no |  |
| 12 | 17 37 42.232 |  $-03$ 14 59.35 | $0.1898\pm 0.0961$ | $-3.961\pm 0.088$ | $-5.138\pm 0.071$ | 15.622 | $0.895$ | yes | AHB |
| 13 | 17 37 26.563 |  $-03$ 17 15.06 | $0.5451\pm 0.0140$ | $-2.361\pm 0.013$ | $-1.307\pm 0.010$ | 12.538 | $1.842$ | no |  |
| 14 | 17 37 33.474 |  $-03$ 15 27.77 | $-0.0213\pm 0.0339$ | $-3.825\pm 0.033$ | $-5.680\pm 0.026$ | 14.980 | $1.689$ | yes | AHB | -10
6626/ | 1 | 18 24 34.602 |  $-24$ 53 21.19 | $0.5888\pm 0.0213$ | $0.742\pm 0.034$ | $-0.457\pm 0.024$ | 12.928 | $0.765$ | no |  |
M28 | 2 | 18 24 28.326 |  $-24$ 54 24.28 | $0.7298\pm 0.0293$ | $1.540\pm 0.039$ | $-0.620\pm 0.028$ | 12.760 | $0.599$ | no |  |
| 3 | 18 24 29.356 |  $-24$ 50 47.10 | $0.5752\pm 0.0282$ | $0.703\pm 0.042$ | $0.210\pm 0.030$ | 13.733 | $0.815$ | no |  |
| 4 | 18 24 31.597 |  $-24$ 49 16.99 | $1.1453\pm 0.0205$ | $0.719\pm 0.023$ | $-3.168\pm 0.017$ | 12.554 | $0.762$ | no |  |
| 5 | 18 24 35.838 |  $-24$ 53 15.87 | $0.1444\pm 0.0242$ | $0.137\pm 0.030$ | $-8.671\pm 0.021$ | 11.610 | $1.755$ | yes | rPAGB | -9
6656/ | 1 | 18 36 13.295 |  $-23$ 52 46.13 | $4.3374\pm 0.0167$ | $12.512\pm 0.018$ | $11.282\pm 0.013$ | 10.969 | $1.043$ | no |  |
M22 | 2 | 18 36 40.101 |  $-23$ 52 51.13 | $3.4277\pm 0.0179$ | $15.181\pm 0.017$ | $-4.332\pm 0.013$ | 11.812 | $1.011$ | no |  |
| 3 | 18 36 49.468 |  $-23$ 55 48.96 | $1.0871\pm 0.0164$ | $-0.813\pm 0.016$ | $-4.461\pm 0.013$ | 11.863 | $0.983$ | no |  |
| 4 | 18 36 35.319 |  $-23$ 48 20.50 | $1.2092\pm 0.0432$ | $2.420\pm 0.038$ | $-4.826\pm 0.028$ | 11.576 | $0.697$ | no |  |
| 5 | 18 36 10.796 |  $-23$ 49 57.14 | $0.3008\pm 0.0180$ | $9.250\pm 0.019$ | $-5.808\pm 0.014$ | 12.519 | $0.668$ | yes | AHB |
| 6 | 18 36 30.544 |  $-23$ 53 58.10 | $0.2797\pm 0.0181$ | $10.187\pm 0.020$ | $-5.710\pm 0.017$ | 10.970 | $1.805$ | yes | AGB |
| 7 | 18 36 24.181 |  $-23$ 52 57.09 | $0.2833\pm 0.0185$ | $10.493\pm 0.021$ | $-6.293\pm 0.014$ | 10.782 | $1.975$ | yes | RGB |
| 8 | 18 35 50.312 |  $-23$ 58 25.91 | $1.0202\pm 0.0437$ | $0.880\pm 0.047$ | $-4.359\pm 0.038$ | 10.999 | $0.578$ | no |  |
| 9 | 18 36 49.548 |  $-24$ 01 16.01 | $0.2440\pm 0.1104$ | $-2.543\pm 0.127$ | $-6.754\pm 0.116$ | 11.898 | $0.950$ | no |  |
| 10 | 18 35 52.789 |  $-23$ 53 34.20 | $1.0688\pm 0.0215$ | $0.383\pm 0.022$ | $-3.565\pm 0.016$ | 10.210 | $1.730$ | no |  |
| 11 | 18 36 33.013 |  $-23$ 54 35.71 | $1.4884\pm 0.0158$ | $5.226\pm 0.018$ | $-14.614\pm 0.015$ | 10.999 | $1.438$ | no |  |
| 12 | 18 36 15.426 |  $-23$ 46 17.40 | $1.0804\pm 0.0182$ | $1.260\pm 0.021$ | $1.393\pm 0.017$ | 12.369 | $0.501$ | no |  |
| 13 | 18 36 10.475 |  $-23$ 46 27.45 | $1.5638\pm 0.0968$ | $3.307\pm 0.099$ | $-2.470\pm 0.080$ | 10.501 | $0.537$ | no |  |
| 14 | 18 35 54.081 |  $-23$ 45 31.73 | $0.2634\pm 0.0188$ | $9.807\pm 0.021$ | $-4.879\pm 0.016$ | 10.931 | $1.750$ | yes | AGB | -8
| 15 | 18 35 43.009 |  $-23$ 48 32.99 | $5.2690\pm 0.0178$ | $-46.562\pm 0.022$ | $-77.378\pm 0.016$ | 10.792 | $0.985$ | no |  |
| 16 | 18 36 29.196 |  $-23$ 49 53.24 | $0.3072\pm 0.0233$ | $4.747\pm 0.022$ | $-0.703\pm 0.016$ | 13.520 | $0.356$ | no |  |
| 17 | 18 36 53.525 |  $-23$ 51 29.50 | $1.2703\pm 0.0167$ | $0.881\pm 0.017$ | $0.937\pm 0.013$ | 9.739 | $1.431$ | no |  |
| 18 | 18 36 28.974 |  $-24$ 04 04.05 | $1.5693\pm 0.0174$ | $4.618\pm 0.020$ | $-6.379\pm 0.016$ | 12.822 | $0.949$ | no |  |
6712 | 1 | 18 53 05.791 |  $-08$ 42 37.85 | $0.0890\pm 0.0156$ | $3.275\pm 0.018$ | $-4.515\pm 0.014$ | 13.135 | $0.556$ | yes | bPAGB | -7
| 2 | 18 53 07.295 |  $-08$ 43 09.29 | $0.3587\pm 0.0250$ | $0.766\pm 0.027$ | $0.328\pm 0.021$ | 13.870 | $0.797$ | no |  |
| 3 | 18 53 01.434 |  $-08$ 42 33.89 | $1.2943\pm 0.0212$ | $6.463\pm 0.025$ | $-0.903\pm 0.022$ | 14.109 | $0.986$ | no |  |
| 4 | 18 53 08.772 |  $-08$ 41 56.66 | $0.1354\pm 0.0196$ | $3.367\pm 0.021$ | $-4.476\pm 0.017$ | 12.025 | $2.443$ | yes | AGB | -6
6779/ | 1 | 19 16 36.583 |  $+30$ 11 17.37 | $0.3612\pm 0.1729$ | $-6.241\pm 0.160$ | $-18.053\pm 0.183$ | 14.423 | $0.969$ | no |  |
M56 | 2 | 19 16 41.278 |  $+30$ 12 48.55 | $0.0486\pm 0.0237$ | $-1.946\pm 0.021$ | $1.598\pm 0.025$ | 15.099 | $-0.038$ | yes | vPAGB | -5
6934 | 1 | 20 34 07.304 |  $+07$ 23 47.01 | $0.9455\pm 0.0213$ | $12.508\pm 0.023$ | $-2.894\pm 0.017$ | 14.528 | $0.874$ | no |  |
7078/ | 1 | 21 29 58.194 |  $+12$ 11 42.55 | $0.0825\pm 0.0435$ | $-0.631\pm 0.047$ | $-3.736\pm 0.039$ | 15.065 | $0.053$ | yes | AHB | -4
M15 | 2 | 21 30 07.438 |  $+12$ 11 07.73 | $0.0962\pm 0.0217$ | $-0.568\pm 0.022$ | $-3.859\pm 0.017$ | 14.313 | $0.137$ | yes | AHB |
| 3 | 21 29 44.092 |  $+12$ 09 16.73 | $1.1896\pm 0.0149$ | $-2.117\pm 0.014$ | $-3.762\pm 0.012$ | 13.477 | $0.910$ | no |  |
| 4 | 21 30 00.789 |  $+12$ 09 43.28 | $-0.5487\pm 0.2111$ | $-0.971\pm 0.219$ | $-2.189\pm 0.192$ | 13.820 | $1.160$ | yes | AGB | -3
| 5 | 21 29 55.072 |  $+12$ 10 14.49 | $-0.1125\pm 0.0343$ | $-0.398\pm 0.036$ | $-3.492\pm 0.033$ | 13.119 | $1.373$ | yes | AGB | -2
| 6 | 21 29 56.179 |  $+12$ 10 17.93 | $0.3868\pm 0.0513$ | $-0.405\pm 0.052$ | $-4.058\pm 0.045$ | 12.352 | $1.511$ | no? |  | -1
| 7 | 21 30 00.981 |  $+12$ 08 41.83 | $-0.4838\pm 0.1057$ | $-0.638\pm 0.109$ | $-2.803\pm 0.091$ | 15.194 | $0.230$ | yes? | AHB | 0
7089/ | 1 | 21 33 34.128 |  $-00$ 53 37.99 | $0.0232\pm 0.0324$ | $3.278\pm 0.034$ | $-2.200\pm 0.021$ | 14.570 | $0.139$ | yes | AHB |
M2 | 2 | 21 33 29.872 |  $-00$ 45 51.60 | $-0.0170\pm 0.0773$ | $3.276\pm 0.091$ | $-2.724\pm 0.065$ | 15.113 | $0.162$ | yes | AHB |