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Related papers: Perhaps they are not Globular Clusters after all

200 papers

Since 2015 there has been a great deal of interest in a supposed new class of galaxy called Ultra Diffuse Galaxies (UDGs). These are large systems with sizes $> 1.5$ kpc and have surface brightness values which are $\mu > 25$ mag…

Astrophysics of Galaxies · Physics 2018-03-20 Christopher J. Conselice

Recently, \citet{vitral2021does} detected a central concentration of dark objects in the core-collapsed globular cluster NGC 6397, which could be interpreted as a subcluster of stellar-mass black holes. However, it is well established…

Ultra diffuse galaxies, characterized by their low surface brightness and large physical size, constitute a subclass of dwarf galaxies that challenge our current understanding of galaxy formation and evolution. In this paper, we probe the…

Globular clusters (GCs) are found ubiquitously in massive galaxies and due to their old ages, they are regarded as fossil records of galaxy evolution. Spectroscopic studies of GC systems are often limited to the outskirts of galaxies, where…

We present the results from a wide-field spectroscopic survey of globular clusters (GCs) in the Virgo Cluster. We obtain spectra for 201 GCs and 55 ultracompact dwarfs (UCDs) using the Hectospec on the Multiple Mirror Telescope, and derive…

We report evidence for dynamically significant rotation in the globular cluster systems of two luminous Virgo dwarf ellipticals, VCC1261 and VCC1528. Including previous results for VCC1087, the globular cluster systems of all three Virgo…

Astrophysics of Galaxies · Physics 2015-05-13 Michael A. Beasley , A. Javier Cenarro , Jay Strader , Jean Brodie

We have obtained deep photometry of NGC 1199 (in HCG 22) and NGC 6868 (in the Telescopium group). Both galaxies are the optically brightest galaxies of their groups. Our analysis of B and R images taken with the Keck II and the VLT/ESO…

Astrophysics · Physics 2009-11-06 C. Da Rocha , C. Mendes de Oliveira , M. Bolte , B. L. Ziegler , T. H. Puzia

We present a preliminary analysis of HST-WFPC2 observations of globular cluster systems in the two brightest galaxies, UGC 9799 (cD) and NGC 1129 (non-cD), located in the center of rich clusters.

Astrophysics · Physics 2007-05-23 Myung Gyoon Lee , Eunhyeuk Kim , Doug Geisler , Terry Bridges , Keith Ashman

The analysis of pseudo-colour diagrams, the so-called chromosome maps, of Galactic globular clusters (GCs) permits to classify them into type I and type II clusters. Type II GCs are characterized by an above-the-average complexity of their…

Astrophysics of Galaxies · Physics 2020-04-15 Matteo Simioni , Antonio Aparicio , Giampaolo Piotto

There is compelling observational evidence that globular clusters (GCs) are quite complex objects. A growing body of photometric results indicate that the evolutionary sequences are not simply isochrones in the observational plane -as…

Astrophysics of Galaxies · Physics 2015-05-14 Angela Bragaglia

NGC 1380 is a lenticular galaxy located near the centre of the Fornax Cluster northeast of NGC 1399. The globular cluster system of this galaxy was previously studied only from the ground. Recent studies of similar early-type galaxies,…

Astrophysics · Physics 2009-11-13 A. L. Chies-Santos , B. X. Santiago , M. G. Pastoriza

Dynamical mass estimates of ultra-compact dwarfs galaxies and massive globular clusters in the Fornax and Virgo clusters and around the giant elliptical Cen A have revealed some surprising results: 1) above about 10^6 M_sun the…

Astrophysics · Physics 2007-10-10 M. Hilker , S. Mieske , H. Baumgardt , J. Dabringhausen

We recently discovered that NGC 3201 has characteristics that set it outside the current twofold classification scheme for Galactic globular clusters (GCs). Most GCs are mono-metallic and show light-element abundance variations (e.g., Na-O…

Solar and Stellar Astrophysics · Physics 2020-03-18 Bruno Dias , Ignacio Araya , João Paulo Nogueira-Cavalcante , Leila Saker , Ahmed Shokry

Following the discovery of spiral structure in IC3328 (Jerjen et al.~2000), we present further evidence that a sizable fraction of bright early-type dwarfs in the Virgo cluster are genuine disk galaxies, or are hosting a disk component.…

Astrophysics · Physics 2009-11-07 Fabio D. Barazza , Bruno Binggeli , Helmut Jerjen

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jay Strader , Giuseppina Fabbiano , Bin Luo , Dong-Woo Kim , Jean P. Brodie , Tassos Fragos , John S. Gallagher , Vassiliki Kalogera , Andrew King , Andreas Zezas

From a quantitative analysis of 413 Virgo cluster early-type dwarf galaxies (dEs) with Sloan Digital Sky Survey imaging data, we find that the dE class can be divided into multiple subpopulations that differ significantly in their…

Astrophysics · Physics 2008-11-26 Thorsten Lisker , Eva K. Grebel , Bruno Binggeli , Katharina Glatt

Although cluster dwarf galaxies are often neglected due to their faintness, recent observations demonstrate that they are critical for understanding the physical processes behind galaxy and cluster formation. Dwarfs are the most common…

Astrophysics · Physics 2007-05-23 Christopher J. Conselice

Their ubiquity and extreme densities make star clusters probes of prime importance of galaxy evolution. Old globular clusters keep imprints of the physical conditions of their assembly in the early Universe, and younger stellar objects,…

Astrophysics of Galaxies · Physics 2018-05-02 Florent Renaud

We use recently compiled position and velocity data for the globular cluster and planetary nebula subsystems in NGC 5128, the nearby giant elliptical, to search for evidence of past dwarf-satellite accretion events. Beyond a 10 arcmin (~11…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Kristin A. Woodley , William E. Harris

We use HST/ACS imaging of 100 early-type galaxies in the ACS Virgo Cluster Survey to investigate the nature of diffuse star clusters (DSCs). Compared to globular clusters (GCs), these star clusters have moderately low luminosities (M_V >…