VEGAS-SSS: Tracing Globular Cluster Populations in the Interacting NGC3640 Galaxy Group

Abstract

Globular clusters (GCs) are among the oldest stellar systems in the universe. As such, GCs population are valuable fossil tracers of galaxy formation and interaction history. We use the multi-band wide-field images obtained with the VST to study the properties of the GC population in an interacting pair of galaxies. We derived ugri photometry over $1.5x1.5de{g}^2$ centred on the galaxy group composed by two elliptical galaxies: NGC3640 and its fainter companion NGC3641. We studied the GC system properties from both the ugri and gri matched catalogs GC candidates were identified based on a combination of photometric properties (colors, magnitudes) and morphometric criteria (concentration index, elongation, FWHM), using sources with well-defined classifications from spectroscopic or imaging data available in the literature and numerical simulations as references. The selection criteria were also applied to empty fields to determine a statistical background correction for the number of identified GC candidates. The 2D density maps of GCs appear to align with the diffuse light patches resulting from merging events of the galaxies. The highest density peak of GCs is observed to be on NGC3641 rather than NGC3640, despite the latter being the more massive galaxy. The azimuthal averaged radial density profiles in both galaxies reveal that the GC population extends beyond the galaxy light profile and indicate the likely presence of an intra-group GC component. A color bimodality in (u-r) and (g-i) is observed for NGC3641, whereas NGC3640 shows a broad unimodal distribution. Analysis of the GC Luminosity Function indicates that both galaxies are roughly located at the same distance (~27Mpc). We provide an estimate of the total number of GCs, and determine the specific frequency for NGC3640, $S_N=2.0\pm 0.6$, which aligns with expectations, while for NGC3641 we find a large $S_N=4.5\pm 1.6$.

37 pages, 23 figures, 13 tables. Accepted for publication in A&A

References in corpus (30)

• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The GALEX Ultraviolet Atlas of Nearby Galaxies
• The Atlas3D project -- XXIX. The new look of early-type galaxies and surrounding fields disclosed by extremely deep optical images
• What is a globular cluster? An observational perspective
• A High Stellar Velocity Dispersion and ~100 Globular Clusters for the Ultra Diffuse Galaxy Dragonfly 44
• A second galaxy missing dark matter in the NGC1052 group
• The Globular Cluster Luminosity Function and Specific Frequency in Dwarf Elliptical Galaxies
• Globular Cluster Systems in Nearby Dwarf Galaxies: I. HST/ACS Observations and Dynamical Properties of Globular Clusters at Low Environmental Density
• The early-type dwarf galaxy population of the Hydra I cluster
• Spatially resolved kinematics and stellar populations of brightest cluster and group galaxies
• Structure and morphology of the MATLAS dwarf galaxies and their central nuclei
• Ultra diffuse galaxies in the MATLAS low-to-moderate density fields
• How large are the globular cluster systems of early-type galaxies and do they scale with galaxy halo properties?
• Dwarf galaxies in the MATLAS survey: Hubble Space Telescope observations of the globular cluster system in the ultra-diffuse galaxy MATLAS-2019
• Galaxy populations in the Hydra I cluster from the VEGAS survey II. The ultra-diffuse galaxy population
• A Complex Luminosity Function for the Anomalous Globular Clusters in NGC1052-DF2 and NGC1052-DF4
• AutoProf -- I. An automated non-parametric light profile pipeline for modern galaxy surveys
• The Fornax Deep Survey with VST. IX. The catalog of sources in the FDS area, with an example study for globular clusters and background galaxies
• Euclid: Early Release Observations -- Dwarf galaxies in the Perseus galaxy cluster
• Does the virial mass drive the intra-cluster light? The relationship between the ICL and M${}_{vir}$ from VEGAS
• VEGAS: A VST Early-type GAlaxy Survey.VI. The diffuse light in HCG 86 from the ultra-deep VEGAS images
• Companions to Isolated Elliptical Galaxies: Revisiting the Bothun-Sullivan Sample
• VEGAS: VST Early-type GAlaxy Survey. V. IC 1459 group: Mass assembly history in low density environments
• Galaxy populations in the Hydra I cluster from the VEGAS survey I. Optical properties of a large sample of dwarf galaxies
• Radial velocities and stellar population properties of 56 MATLAS dwarf galaxies observed with MUSE
• Euclid: Early Release Observations -- Globular clusters in the Fornax galaxy cluster, from dwarf galaxies to the intracluster field
• Globular Cluster Systems of Relic Galaxies
• Substructure in the Globular Cluster Populations of the Virgo Cluster Elliptical Galaxies M84 and M86
• Spatial Structures in the Globular Cluster Distribution of Fornax Cluster Galaxies
• A study of globular clusters in a lenticular galaxy in Hydra I from deep HST/ACS photometry

Cited by in corpus (5)

• Major Mergers Mean Major Offset: Drivers of Intrinsic Scatter in The $M_{GCS}-M_h$ Scaling Relation for Massive Elliptical Galaxies
• Looking into the faintEst WIth MUSE (LEWIS): Exploring the nature of ultra-diffuse galaxies in the Hydra-I cluster IV. A study of the Globular Cluster population in four UDGs
• VEGAS-SSS: An intra-group component in the globular cluster system of NGC 5018 group of galaxies using VST data
• Intracluster globular clusters as tracers of the mass assembly of the Hydra I galaxy cluster
• The contribution of the color space in LSST-like photometry for the selection of extragalactic globular cluster candidates