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1351. Globular clusters around NGC 1399
ID:
ivo://CDS.VizieR/J/AJ/127/2114
Title:
Globular clusters around NGC 1399
Short Name:
J/AJ/127/2114
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radial velocities of 468 globular clusters around NGC 1399, the central galaxy in the Fornax cluster, have been obtained with FORS2 and the Mask Exchange Unit (MXU) at the ESO Very Large Telescope. This is the largest sample of globular cluster velocities around any galaxy obtained so far. The mean velocity uncertainty is 50km/s. This data sample is accurate and large enough to be used in studies of the mass distribution of NGC 1399 and the properties of its globular cluster system. Here we describe the observations and the reduction procedure, and we discuss the uncertainties of the resulting velocities. The complete sample of cluster velocities that is used in a dynamical study of NGC 1399 is tabulated. A subsample is compared with previously published values.
1352. Globular clusters around NGC 1407
ID:
ivo://CDS.VizieR/J/AJ/137/4956
Title:
Globular clusters around NGC 1407
Short Name:
J/AJ/137/4956
Date:
21 Oct 2021
Publisher:
CDS
Description:
NGC 1407 is the central elliptical in a nearby evolved group of galaxies apparently destined to become a galaxy cluster core. We use the kinematics of globular clusters (GCs) to probe the dynamics and mass profile of the group's center, out to a radius of 60kpc (~10 galaxy effective radii)-the most extended data set to date around an early-type galaxy. This sample consists of 172 GC line-of-sight velocities, most of them newly obtained using Keck/DEIMOS, with a few additional objects identified as dwarf-globular transition objects or as intragroup GCs.
1353. Globular clusters as gravitational lenses
ID:
ivo://CDS.VizieR/J/PAZh/33/403
Title:
Globular clusters as gravitational lenses
Short Name:
J/PAZh/33/403
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on the SDSS catalog, we have found new close quasar-galaxy pairs. We analyze the radial distribution of quasars from pairs around galaxies of different types. We show that the quasars from pairs follow the density profile of halo globular clusters. This is new observational evidence that the quasars projected onto the halos of galaxies are magnified by gravitational lensing by halo globular clusters.
1354. Globular clusters in ACSVCS early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/773/L27
Title:
Globular clusters in ACSVCS early-type galaxies
Short Name:
J/ApJ/773/L27
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a determination of the two-dimensional shape parameters of the blue and red globular cluster systems (GCSs) in a large number of elliptical galaxies and lenticular galaxies (early-type galaxies, called ETGs). We use a homogeneous data set of the globular clusters in 23 ETGs obtained from the HST/ACS Virgo Cluster Survey. The position angles of both blue and red GCSs show a correlation with those of the stellar light distribution, showing that the major axes of the GCSs are well aligned with those of their host galaxies. However, the shapes of the red GCSs show a tight correlation with the stellar light distribution as well as with the rotation property of their host galaxies, while the shapes of the blue GCSs do much less. These provide clear geometric evidence that the origins of the blue and red globular clusters are distinct and that ETGs may have dual halos: a blue (metal-poor) halo and a red (metal-rich) halo. These two halos show significant differences in metallicity, structure, and kinematics, indicating that they are formed in two distinguishable ways. The red halos might have formed via dissipational processes with rotation, while the blue halos are through accretion.
1355. Globular clusters in 3 early-type galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/420/1317
Title:
Globular clusters in 3 early-type galaxies
Short Name:
J/MNRAS/420/1317
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the age and metallicity distributions of bright globular clusters (GCs) in the candidate intermediate-age early-type galaxies NGC 3610, 584 and 3377 using a combination of new Gemini's Near InfraRed Imager and Spectrometer K'-band imaging and existing optical VI photometry from Hubble Space Telescope data.
1356. Globular Clusters in Ellipticals
ID:
ivo://CDS.VizieR/J/AJ/108/2087
Title:
Globular Clusters in Ellipticals
Short Name:
J/AJ/108/2087
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present VRI photometry for the globular cluster systems (GCS's) of ten elliptical and S0 galaxies in Virgo and Leo. We find that the V-I color (metallicity) distributions are quite different from galaxy to galaxy. One extreme is represented by NGC 4374 with a narrow, blue distribution. NGC 4472 has a very broad, uniform distribution in color, corresponding to -1.8 < [Fe/H] < +0.47. At the other extreme is NGC 4365, which is weighted towards red colors, and possibly has a peculiar luminosity function. We suggest that this variation of GCS metallicity depends on environment, with formation of high metallicity globular clusters inhibited in higher density environments. We compare color-color plots of the GCS's of these galaxies with the Milky Way GCS and with integrated isochrones. We find good agreement with the galaxies studied here except that the isochrones predict colors which are slightly too bright in the I band for metal-rich clusters. We also consider the radial GC color distributions in these galaxies. We find evidence for a V-I color gradient only in NGC 4374, in the sense of redder clusters toward the center of the galaxy but warn that possible systematic effects must be ruled out with the new data. Lastly, using the surface brightness fluctuation distances to these galaxies, we find supporting evidence for the universality of the globular cluster luminosity function.
1357. Globular clusters in five early-type galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/416/155
Title:
Globular clusters in five early-type galaxies
Short Name:
J/MNRAS/416/155
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we present deep high-quality photometry of globular cluster systems (GCSs) belonging to five early-type galaxies, covering a range of mass and environment. Photometric data were obtained with the Gemini North and Gemini South telescopes in the filter passbands g', r' and i'. The combination of these filters with good seeing conditions allows an excellent separation between globular cluster (GC) candidates and unresolved field objects.
1358. Globular clusters in M104
ID:
ivo://CDS.VizieR/J/MNRAS/401/1965
Title:
Globular clusters in M104
Short Name:
J/MNRAS/401/1965
Date:
21 Oct 2021
Publisher:
CDS
Description:
Images from the Hubble Space Telescope Advanced Camera for surveys are used to carry out a new photometric study of the globular clusters (GCs) in M104, the Sombrero galaxy. The primary focus of our study is the characteristic distribution function of linear sizes [size distribution function (SDF)] of the GCs. We measure the effective radii for 652 clusters with point spread function-convolved King and Wilson dynamical model fits. The SDF is remarkably similar to those measured for other large galaxies of all types, adding strong support to the view that it is a 'universal' feature of GC systems. We use the Sombrero and Milky Way data and the formation models of Baumgardt & Kroupa (2007MNRAS.380.1589B) to develop a more general interpretation of the SDF for GCs.
1359. Globular clusters in M87
ID:
ivo://CDS.VizieR/J/AJ/106/493
Title:
Globular clusters in M87
Short Name:
J/AJ/106/493
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep integrated Washington CCD photometry of the extremely populous globular cluster system of NGC 4486 (M87) in Virgo. The metallicities of 407 of the best candidates with T1 < 22 have been estimated from the (C-T1) color. These values are internally precise to ~0.15dex and accurate to ~0.25dex. The mean metallicity of the globular clusters is [Fe/H] = -0.86dex, with a formal standard error of the mean of 0.03dex but a more realistic uncertainty of about 0.2dex. This value is higher than that of the corresponding means of the globular clusters in the Galaxy and M31, but similar to those of the globular clusters in NGC 1399 and NGC 5128, as expected from the relative parent galaxy luminosities. Approximately 10% of the clusters exceed solar abundance, similar to the case for the globular clusters in NGC 1399 and NGC 5128. As found by Couture et al. [ApJS, 73, 671 (1990)], there is a large metallicity dispersion at any radius, with a sigma ~ 0.65dex. However, in contrast to their result and that of previous small-field CCD studies, the globular clusters display a marked gradient in both mean (M-T1) and (C-T1) color with galactocentric distance. The mean metallicity decreases by some 0.6dex over the radial extent of the cluster sample. This result is consistent with the early photographic study by Strom et al. [ApJ, 245, 416 (1981)]. The metallicity distribution function is remarkably similar to that of NGC 1399 found by Ostrov et al. [AJ, 105, 1762 (1993)] using the same technique. The two central cluster ellipticals show significant peaks at very similar metallicities, indicating similar formation and enrichment histories. We also find that this structure in the metallicity distribution function persists to radii where the halo light is dominated by the cD envelope.
1360. Globular clusters in M31 and the Galaxy
ID:
ivo://CDS.VizieR/J/AJ/140/1043
Title:
Globular clusters in M31 and the Galaxy
Short Name:
J/AJ/140/1043
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Milky Way system and the Andromeda galaxy experienced radically different evolutionary histories. Nevertheless, it is found that these two galaxies ended up with globular cluster systems in which individual clusters have indistinguishable distributions of half-light radii. Furthermore, globulars in both M31 and the Galaxy are found to have radii that are independent of their luminosities. In this respect, globular clusters differ drastically from early-type galaxies in which half-light radius and luminosity are tightly correlated. Metal-rich globular clusters in M31 occupy a slightly larger volume than do those in the Galaxy. The specific globular cluster frequency in the Andromeda galaxy is found to be significantly higher than it is in the Milky Way system. The present discussion is based on the 107 Galactic globular clusters, and 200 putative globulars in M31, for which UBV photometry was available.

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