- ID:
- ivo://CDS.VizieR/J/ApJ/835/123
- Title:
- Globular clusters in NGC 474 from CFHT obs.
- Short Name:
- J/ApJ/835/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Globular clusters (GCs) are some of the most visible tracers of the merging and accretion histories of galaxy halos. Metal-poor GCs, in particular, are thought to arrive in massive galaxies largely through dry, minor merging events, but it is rare to see a direct connection between GCs and visible stellar streams. NGC 474 is a post-merger early-type galaxy with dramatic fine structures made of concentric shells and radial streams that have been more clearly revealed by deep imaging. We present a study of GCs in NGC 474 to better establish the relationship between merger-induced fine structure and the GC system. We find that many GCs are superimposed on visible streams and shells, and about 35% of GCs outside 3R_e,galaxy_ are located in regions of fine structure. The spatial correlation between GCs and fine structure is significant at the 99.9% level, which shows that this correlation is not coincidental. The colors of GCs on fine structures are mostly blue, and we also find an intermediate-color population that is dominant in the central region and that will likely passively evolve to have colors consistent with a traditional metal-rich GC population. The association of the blue GCs with fine structures is direct confirmation that many metal-poor GCs are accreted onto massive galaxy halos through merging events and that the progenitors of these mergers are sub-L^*^ galaxies.
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- ID:
- ivo://CDS.VizieR/J/AJ/127/2674
- Title:
- Globular clusters in Sculptor group
- Short Name:
- J/AJ/127/2674
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use CTIO 4m Mosaic II images taken with the Washington CM and Harris R filters to identify candidate globular clusters in the six major galaxies of the Sculptor group: NGC 45, 55, 247, 254, 300, and 7793. From follow-up spectroscopy with Hydra-CTIO, we find 19 new globular clusters in NGC 55, 247, 253, and 300, bringing the total number of known Sculptor group globular clusters to 36. The newly discovered clusters have spectroscopic ages consistent with those of old Milky Way globular clusters, and the majority are metal-poor.
- ID:
- ivo://CDS.VizieR/J/ApJS/171/101
- Title:
- Globular clusters in the ACS Virgo cluster survey
- Short Name:
- J/ApJS/171/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the luminosity function of the globular clusters (GCs) belonging to the early-type galaxies observed in the ACS Virgo Cluster Survey. We have obtained maximum likelihood estimates for a Gaussian representation of the globular cluster luminosity function (GCLF) for 89 galaxies. We have also fit the luminosity functions with an "evolved Schechter function", which is meant to reflect the preferential depletion of low-mass GCs, primarily by evaporation due to two-body relaxation, from an initial Schechter mass function similar to that of young massive clusters in local starbursts and mergers. We find a highly significant trend of the GCLF dispersion {sigma} with galaxy luminosity, in the sense that the GC systems in smaller galaxies have narrower luminosity functions. The GCLF dispersions of our Galaxy and M31 are quantitatively in keeping with this trend, and thus the correlation between {sigma} and galaxy luminosity would seem more fundamental than older notions that the GCLF dispersion depends on Hubble type. We show that this narrowing of the GCLF in a Gaussian description is driven by a steepening of the cluster mass function above the classic turnover mass, as one moves to lower luminosity host galaxies. In a Schechter function description, this is reflected by a steady decrease in the value of the exponential cutoff mass scale. We argue that this behavior at the high-mass end of the GC mass function is most likely a consequence of systematic variations of the initial cluster mass function rather than long-term dynamical evolution.
- ID:
- ivo://CDS.VizieR/J/MNRAS/272/391
- Title:
- Globular clusters in the Magellanic Clouds
- Short Name:
- J/MNRAS/272/391
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report JHK results of observations of 12 globular clusters in the Large Magellanic Cloud (LMC), and present colour-magnitude diagrams down to K=16 (corresponding to absolute K~-2.6) for ~450 stars in these clusters.
- ID:
- ivo://CDS.VizieR/VII/195
- Title:
- Globular Clusters in the Milky Way
- Short Name:
- VII/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog compiled by William E. Harris contains basic parameters on distances, velocities, metallicities, luminosities, colors, and dynamical parameters for 146 objects regarded as globular clusters in the Milky Way galaxy. A complete list of source references is given in the companion file "sources". The original files are also accessible through WorldWideWeb, at URL http://www.physics.mcmaster.ca/Globular.html This version corresponds to revision: April 1, 1996
- ID:
- ivo://CDS.VizieR/VII/202
- Title:
- Globular Clusters in the Milky Way
- Short Name:
- VII/202
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog compiled by William E. Harris contains basic parameters on distances, velocities, metallicities, luminosities, colors, and dynamical parameters for 147 objects regarded as globular clusters in the Milky Way galaxy. A complete list of source references is given in the companion file "sources". The original files are also accessible through WorldWideWeb, at URL http://www.physics.mcmaster.ca/Globular.html This version corresponds to revision: May 15, 1997, and supersedes the previous version (Catalog <VII/195>).
- ID:
- ivo://CDS.VizieR/J/A+A/328/83
- Title:
- Globular clusters luminosity function
- Short Name:
- J/A+A/328/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data of figure 1 of the paper, namely the luminosity function of globular clusters in bolometric magnitude. The original HST magnitude is given, then the corresponding bolometric magnitude and the converted luminosity function. The vertical scale of the LF is arbitrary (it is the scale used on the figure). The conversion between the HST and bolometric magnitudes uses a spline fit of the theoretical models of Baraffe et al. (1997A&A...327.1054B), for the appropriate metallicities. The name of the cluster and of the observational paper main authors are given as a header, followed by the magnitudes description and the data.
- ID:
- ivo://CDS.VizieR/J/MNRAS/488/3024
- Title:
- Globular clusters members with Gaia DR2
- Short Name:
- J/MNRAS/488/3024
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present a method to identify possible members of globular clusters using data from Gaia DR2. The method consists of two stages: the first one based on a clustering algorithm, and the second one based on the analysis of the projected spatial distribution of stars with different proper motions. In order to confirm that the clusters members extracted by the method correspond to actual globular clusters, the spatial distribution, the vector point diagram of the proper motions, and the colour-magnitude diagrams are analysed. We apply the developed method to eight clusters: NGC 1261, NGC 3201, NGC 6139, NGC 6205, NGC 6362, NGC 6397, NGC 6712, and Palomar 13; we show the number of members extracted, the mean proper motions derived from them and finally we compare our results with other authors. In order to analyse the efficiency of the extraction method, we perform an estimation of the completeness and the degree of contamination of the extracted members.
- ID:
- ivo://CDS.VizieR/J/ApJ/760/87
- Title:
- Globular clusters of M60 with HST
- Short Name:
- J/ApJ/760/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present g and z photometry and size estimates for globular clusters (GCs) in the massive Virgo elliptical NGC 4649 (M60) using a five-pointing Hubble Space Telescope/Advanced Camera for Surveys mosaic. The metal-poor GCs show a monotonic negative metallicity gradient of -0.43+/-0.10dex per dex in radius over the full radial range of the data, out to ~24kpc. There is evidence for substantial color substructure among the metal-rich GCs. The metal-poor GCs have typical sizes ~0.4pc larger than the metal-rich GCs out to large galactocentric distances (>~20kpc), favoring an intrinsic explanation for the size difference rather than projection effects. There is no clear relation between half-light radius and galactocentric distance beyond ~15kpc, suggesting that the sizes of GCs are not generically set by tidal limitation. Finally, we identify ~20 candidate ultracompact dwarfs that extend down to surprisingly faint absolute magnitudes (M_z_~-8.5), and may bridge the gap between this class and "extended clusters" in the Local Group. Three of the brighter candidates have published radial velocities and can be confirmed as bona fide ultracompact dwarfs; follow-up spectroscopy will determine the nature of the remainder of the candidates.
- ID:
- ivo://CDS.VizieR/J/MNRAS/436/1172
- Title:
- Globular Clusters of NGC 4278 in SLUGGS
- Short Name:
- J/MNRAS/436/1172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use multipointing Hubble Space Telescope Advanced Camera for Surveys and wide field Subaru Suprime-Cam imaging to study the globular cluster system of the L* elliptical galaxy NGC 4278. We have also obtained a handful of new globular cluster spectra with the Keck Deep Imaging Multi-Object Spectrograph. We determine the globular cluster surface density profile and use it to calculate the total number of globular clusters, finding the system to be slightly more populous than average for galaxies of its luminosity. We find clear evidence for bimodality in the globular cluster colour distribution and for a colour-magnitude relation in the blue subpopulation (a 'blue tilt'). We also find negative radial colour gradients in both colour subpopulations of equal strength which are similar in strength to those reported in other galaxies. The sizes of NGC 4278's globular clusters decrease with redder colours and increase with galactocentric radius. The ratio of the sizes of blue to red globular clusters is independent of galactocentric radius demonstrating that internal effects are responsible for the size difference with colour.
