Globular cluster clustering and tidal features around ultra compact dwarf galaxies in the halo of NGC1399

Abstract

We present a novel approach to constrain the formation channels of Ultra-Compact Dwarf Galaxies (UCDs). This inhomogeneous class of objects of remnants of tidally stripped dwarf elliptical galaxies and high mass globular clusters. We use three methods to unravel their nature: 1) we analysed 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, we have studied the detailed structural composition of a large sample of 97 UCDs in the halo of NGC1399, the central galaxy of the Fornax cluster, by analysing theirsurface brightness profiles. We derived the structural parameters of 13 extended UCDs modelling them with a single Sersic function and decomposing them into composite King and Sersic profiles. We find evidence for faint stellar envelopes at mu=~26 mag\arcsec^-2 surrounding the UCDs up to an extension of 90pc 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 ~350pc around UCD-FORS2. We searched for local overdensities in the spatial distribution of globular clusters within the halo of NGC1399, to see if they are related to the positions of the UCDs. We found a local overabundance of globular clusters on a scale of <1kpc around UCDs, when we compare 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.

21 pages, 14 figures, accepted for publication in A&A

References in corpus (17)

• A Supermassive Black Hole in an Ultracompact Dwarf Galaxy
• The AIMSS Project I: Bridging the Star Cluster - Galaxy Divide
• Nuclear star clusters in 228 spiral galaxies in the HST/WFPC2 archive: catalogue and comparison to other stellar systems
• The ACS Fornax Cluster Survey. I. Introduction to the Survey and Data Reduction Procedures
• The Nature of UCDs: Internal Dynamics from an Expanded Sample and Homogeneous Database
• Large-scale study of the NGC 1399 globular cluster system in Fornax
• Contribution of stripped nuclear clusters to globular cluster and ultra-compact dwarf galaxy populations
• The Next Generation Virgo Cluster Survey. VI. The Kinematics of Ultra-compact Dwarfs and Globular Clusters in M87
• The Globular Cluster Migratory Origin of Nuclear Star Clusters
• Structural Properties of Ultra-Compact Dwarf Galaxies in the Fornax and Virgo Clusters
• The early-type dwarf galaxy population of the Hydra I cluster
• The early-type dwarf galaxy population of the Centaurus cluster
• The dark matter halo of NGC 1399 - CDM or MOND?
• Stellar Population Constraints on the Dark Matter Content and Origin of Ultra-Compact Dwarf Galaxies
• Compact Stellar Systems around NGC 1399
• A new isolated dSph galaxy near the Local Group
• The colour-magnitude relation of Globular Clusters in Centaurus and Hydra - Constraints on star cluster self-enrichment with a link to massive Milky Way GCs

Cited by in corpus (36)

• Euclid. I. Overview of the Euclid mission
• Nuclear Star Clusters
• The Fornax Deep Survey with VST. I. The extended and diffuse stellar halo of NGC~1399 out to 192 kpc
• The Fornax Deep Survey (FDS) with VST. VI. Optical properties of the dwarf galaxies in the Fornax cluster
• Structure and morphology of the MATLAS dwarf galaxies and their central nuclei
• Star Clusters in Evolving Galaxies
• VEGAS-SSS II: Comparing the globular cluster systems in NGC3115 and NGC1399 using VEGAS and FDS survey data
• Metal-poor nuclear star clusters in two dwarf galaxies near Centaurus A suggesting formation from the in-spiraling of globular clusters
• The correlation between the sizes of globular cluster systems and their host dark matter haloes
• Constraining ultra-compact dwarf galaxy formation with galaxy clusters in the local universe
• The Fornax Cluster VLT Spectroscopic Survey. I - VIMOS spectroscopy of compact stellar systems in the Fornax core region
• The Next Generation Virgo Cluster Survey. XXXIV. Ultra-Compact Dwarf (UCD) Galaxies in the Virgo Cluster
• Upper limits on the presence of central massive black holes in two ultra-compact dwarf galaxies in Centaurus A
• An evolutionary continuum from nucleated dwarf galaxies to star clusters
• A Gaia-based catalog of candidate stripped nuclei and luminous globular clusters in the halo of Centaurus A
• Peculiar compact stellar systems in the Fornax cluster
• Stellar Population Properties of Ultracompact Dwarfs in M87: a Mass-metallicity Correlation Connecting Low-metallicity Globular Clusters and Compact Ellipticals
• Do ultra compact dwarf galaxies form monolithically or as merged star cluster complexes?
• Ultra-compact dwarfs beyond the centre of the Fornax galaxy cluster: Hints of UCD formation in low-density environments
• The Second Nucleus of NGC 7727: Direct Evidence for the Formation and Evolution of an Ultracompact Dwarf Galaxy
• A consistency-test for determining whether ultra-compact dwarf galaxies could be the remnant nuclei of threshed galaxies
• Is There a Fundamental Upper Limit to the Mass of a Star Cluster?
• The assembly history of the nearest S0 galaxy NGC 3115 from its kinematics out to six half-light radii
• Starbursting Nuclei in Old Dwarf Galaxies
• Contribution of stripped nuclei to the ultracompact dwarf galaxy population in the Virgo Cluster
• An Enhanced Massive Black Hole Occupation Fraction Predicted in Cluster Dwarf Galaxies
• Testing the tidal stripping scenario of ultra-compact dwarf galaxy formation by using internal properties
• Euclid: Early Release Observations of diffuse stellar structures and globular clusters as probes of the mass assembly of galaxies in the Dorado group
• Chandra Detection of Intra-cluster X-ray Sources in Fornax
• Distribution of star formation rates during the rapid assembly of NGC 1399 as deduced from its globular cluster system
• On the relationship between metallicity distributions of globular clusters and of circumgalactic gas
• The contribution of supermassive black holes in stripped nuclei to the supermassive black hole population of UCDs and galaxy clusters
• The creation of a massive UCD by tidal threshing from NGC 936
• Dwarf galaxies in the MATLAS Survey: Hubble Space Telescope observations of nuclear star clusters
• Asymmetry at Low Surface Brightness as an Indicator of Environmental Processes in the Fornax Cluster
• On the Tidal Formation of Dark Matter Deficient Galaxies