The<i>HST</i>/ACS Coma Cluster Survey - V. Compact stellar systems in the Coma Cluster

Price, James; Phillipps, S.; Huxor, Avon; Trentham, Neil; Ferguson, Henry C.; Marzke, Ronald O.; Hornschemeier, A. E.; Goudfrooij, Paul; Hammer, D.; Tully, R. Brent; Chiboucas, Kristin; Smith, Russell J.; Carter, D.; Merritt, David; Balcells, M.; Erwin, Peter; Puzia, Thomas H.

doi:10.1111/j.1365-2966.2009.15122.x

Cited by 73 publications

(99 citation statements)

References 97 publications

(149 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These parameters could also lead to a classification of CcGV19b as an EO. The observed mass-to-light ratio of about 13 (Price et al 2009), which is about a factor of three larger than that of VUCD7 and UCD3 (Evstigneeva et al 2007;, suggests rather a galactic origin. However, the vast majority of EOs, about 96%, do not have observed velocity dispersions (see Fig.…”

Section: Discussionmentioning

confidence: 89%

See 1 more Smart Citation

A catalog of extended clusters and ultra-compact dwarf galaxies

Kroupa

2012

A&A

View full text Add to dashboard Cite

Context. In the past decade, very extended old stellar clusters with masses in the range from a few 10 4 to 10 8 M and effective radii larger than 10 pc have been found in various types of galaxies in different environments. Objects with masses comparable to normal globular clusters (GCs) are called extended clusters (ECs), while objects with masses in the dwarf galaxy regime are called ultra-compact dwarf galaxies (UCDs). Aims. The paper analyses the observational parameters total luminosity, M V , effective radius, r eff , and projected distance to the host galaxy, R proj , of all known ECs and UCDs and the dependence of these parameters on the type and the total luminosity of their host galaxy. Methods. We searched the available literature to compile a catalog of star clusters with effective radii larger than 10 pc. As there is no clear distinction between ECs and UCDs, both types of objects will be called extended stellar objects -abbreviated "EOs" -in this paper.Results. In total, we found 813 EOs of which 171 are associated with late-type galaxies and 642 EOs associated with early-type galaxies. EOs cover a luminosity range from about M V = −4 to −14 mag. However, the vast majority of EOs brighter than M V = −10 mag are associated with giant elliptical galaxies. At each magnitude extended objects are found with effective radii between 10 pc and an upper size limit, which shows a clear trend: the more luminous the object the larger is the upper size limit. For EOs associated with early-and late-type galaxies, the EO luminosity functions peak at −6.40 mag and −6.47 mag, respectively, which is about one magnitude fainter than the peak of the GC luminosity function. EOs and GCs form a coherent structure in the r eff vs. M V parameter space, while there is a clear gap between EOs and early-type dwarf galaxies. However, there is a small potential overlap at the high-mass end, where the most extended EOs are close to the parameters of some compact elliptical galaxies. We compare the EO sample with the numerical models of a previous paper and conclude that the parameters of the EO sample as a whole can be very well explained by a star cluster origin, where EOs are the results of merged star clusters of cluster complexes.

show abstract

Section: Discussionmentioning

confidence: 89%

“…The Coma Cluster compact elliptical galaxy CcGV19b (Price et al 2009), which has a luminosity of M V ≈ −14.5 mag and an effective radius of r eff = 72 pc, is located at a projected distance of 68 kpc to NGC 4874. These parameters could also lead to a classification of CcGV19b as an EO.…”

Section: Discussionmentioning

confidence: 99%

A catalog of extended clusters and ultra-compact dwarf galaxies

Kroupa

2012

A&A

View full text Add to dashboard Cite

show abstract

“…The light green triangles are dSphs in the Local Group from McConnachie (2012). The inverted green triangles are compact ellipticals from Price et al (2009). Light green plus signs represent early-type galaxies from Ferrarese et al (2006).…”

Section: Luminosity-effective-radius Relationmentioning

confidence: 99%

Globular cluster clustering and tidal features around ultra-compact dwarf galaxies in the halo of NGC 1399

Voggel¹,

Hilker²,

Richtler³

2016

A&A

View full text Add to dashboard Cite

We present a novel approach to constrain the formation channels of ultra-compact dwarf galaxies (UCDs). They most probably are an inhomogeneous class of objects, composed of remnants of tidally stripped dwarf elliptical galaxies and star clusters that occupy the high mass end of the globular cluster luminosity function. We use three methods to unravel their nature: 1) we analyzed their surface brightness profiles; 2) we carried out a direct search for tidal features around UCDs; and 3) we compared the spatial distribution of GCs and UCDs in the halo of their host galaxy. Based on FORS2 observations under excellent seeing conditions, we studied the detailed structural composition of a large sample of 97 UCDs in the halo of NGC 1399, the central galaxy of the Fornax cluster, by analyzing their surface brightness profiles. We found that 13 of the UCDs were resolved above the resolution limit of 23 pc and we derived their structural parameters fitting a single Sérsic function. When decomposing their profiles into composite King and Sérsic profiles, we find evidence for faint stellar envelopes at µ =∼ 26 mag arcsec −2 , surrounding the UCDs up to an extension of 90 pc in radius. We also show new evidence for faint asymmetric structures and tidal tail-like features surrounding several of these UCDs, a possible tracer of their origin and assembly history within their host galaxy halos. In particular, we present evidence for the first discovery of a significant tidal tail with an extension of ∼350 pc around UCD-FORS 2. Finally, we studied the local overdensities in the spatial distribution of globular clusters within the halo of NGC 1399 out to 110 kpc to see if they are related to the positions of the UCDs. We found a local overabundance of globular clusters on a scale of ≤1 kpc around UCDs, when we compared it to the distribution of globulars from the host galaxy. This effect is strongest for the metal-poor blue GCs. We discuss how likely it is that these clustered globulars were originally associated with the UCD, either as globular cluster systems of a nucleated dwarf galaxy that was stripped down to its nucleus, or as a surviving member of a merged super star cluster complex.

show abstract

“…Between these two cluster populations is largely the realm of background galaxies, although a few other members are noted. These are the compact dwarf ellipticals (cE) (15), which either form a third population of member galaxies, or follow a continuous sequence with the UCDs. The latter possibility hinges on filling the 1.5 magnitude gap between the two populations, which we have thus far been unsuccessful in accomplishing.…”

Section: Propertiesmentioning

confidence: 99%

UCDs in the Coma Cluster

Chiboucas

Tully

Marzke

et al. 2011

EAS Publications Series

Self Cite

View full text Add to dashboard Cite

Abstract. As part of the HST/ACS Coma Cluster Treasury Survey, we have undertaken a Keck/LRIS spectroscopic campaign to determine membership for faint dwarf galaxies. In the process, we discovered a population of Ultra Compact Dwarf galaxies (UCDs) in the core region of the Coma cluster. At the distance of Coma, UCDs are expected to have angular sizes 0.01 < R e < 0.2 arcsec. With ACS imaging, we can resolve all but the smallest ones with careful fitting. Candidate UCDs were chosen based on magnitude, color, and degree of resolution. We spectroscopically confirm 27 objects as bona fide UCD members of the Coma cluster, a 60% success rate for objects targeted with M R < −12. We attribute the high success rate in part to the high resolution of HST data and to an apparent large population of UCDs in Coma. We find that the UCDs tend to be strongly clustered around giant galaxies, at least in the core region of the cluster, and have a distribution and colors that are similar to globular clusters. These findings suggest that UCDs are not independent galaxies, but rather have a star cluster origin. This current study provides the dense environment datapoint necessary for understanding the UCD population.

show abstract

TheHST/ACS Coma Cluster Survey - V. Compact stellar systems in the Coma Cluster

Cited by 73 publications

References 97 publications

A catalog of extended clusters and ultra-compact dwarf galaxies

A catalog of extended clusters and ultra-compact dwarf galaxies

Globular cluster clustering and tidal features around ultra-compact dwarf galaxies in the halo of NGC 1399

UCDs in the Coma Cluster

Contact Info

Product

Resources

About