The complex globular cluster system of the S0 galaxy NGC 4382 in the outskirts of the Virgo Cluster

Abstract

NGC 4382 is a merger-remnant galaxy that has been classified as morphological type E2, S0, and even Sa. In this work, we performed a photometric and spectroscopic analysis of the globular cluster (GC) system of this peculiar galaxy in order to provide additional information about its history. We used a combination of photometric data in different filters, and multi-object and long-slit spectroscopic data obtained using the Gemini/GMOS instrument. The photometric analysis of the GC system, using the Gaussian Mixture Model algorithm in the colour plane, reveals a complex colour distribution within $R_{\mathrm{gal}}<5$ arcmin (26.1 kpc), showing four different groups: the typical blue and red subpopulations, a group with intermediate colours, and the fourth group towards even redder colours. From the spectroscopic analysis of 47 GCs, confirmed members of NGC\,4382 based on radial velocities, we verified 3 of the 4 photometric groups from the analysis of their stellar populations using the ULySS code. NGC 4382 presents the classic blue ($10.4\pm 2.8$ Gyr, $[Fe/H]=-1.48\pm 0.18$ dex) and red ($12.1\pm 2.3$ Gyr, $[Fe/H]=-0.64\pm 0.26$ dex) GCs formed earlier in the lifetime of the galaxy, and a third group of young GCs ($2.2\pm 0.9$ Gyr; $[Fe/H]=-0.05\pm 0.28$ dex). Finally, analysis of long-slit data of the galaxy reveals a luminosity-weighted mean age for the stellar population of $\sim$2.7 Gyr, and an increasing metallicity from [Fe/H]=$-0.1$ to $+0.2$ dex in $R_{\mathrm{gal}}<10$ arcsec (0.87 kpc). These values, and other morphological signatures in the galaxy, are in good agreement with the younger group of GCs, indicating a common origin as a result of a recent merger.

20 pages, 24 figures. Accepted to be published in MNRAS

References in corpus (23)

• Evolutionary Stellar Population Synthesis with MILES. Part I: The Base Models and a New Line Index System
• Dissipation and Extra Light in Galactic Nuclei: II. 'Cusp' Ellipticals
• The SAURON project - VIII. OASIS/CFHT integral-field spectroscopy of elliptical and lenticular galaxy centres
• Spectroscopic ages and metallicities of stellar populations: validation of full spectrum fitting
• The Origin of S0s in Clusters: evidence from the bulge and disc star formation histories
• Stellar populations of Globular Clusters in the Elliptical galaxy NGC1407
• Gemini/GMOS Spectroscopy of the Spheroid and Globular Cluster System of NGC 3923
• Formation of S0 galaxies through mergers. Evolution in the Tully-Fisher relation since $z\sim 1$
• The complex star cluster system of NGC 1316 (Fornax A)
• The extremely populated globular cluster system of the lenticular galaxy NGC 6861
• Globular Clusters As Tracers of Fine Structure in the Dramatic Shell Galaxy NGC 474
• The SLUGGS survey: combining stars, globular clusters and planetary nebulae to understand the assembly history of early-type galaxies from their large radii kinematics
• The merger remnant NGC 3610 and its globular cluster system: a large-scale study
• Tracing the Assembly History of NGC 1395 through its Globular Cluster System
• Intermediate-age Globular Clusters in Four Galaxy Merger Remnants
• Spatial Structures In the Globular Cluster Distribution of the Ten Brightest Virgo Galaxies
• A Wide-field Photometric Survey of Globular Clusters in the Peculiar Early-type Galaxy M85
• Extended Star Clusters in NGC 1023 from HST/ACS Mosaic Imaging
• The assembly history of the nearest S0 galaxy NGC 3115 from its kinematics out to six half-light radii
• Revealing the formation mechanism of the shell galaxy NGC474 with MUSE
• The ACS Fornax Cluster Survey. XII. Diffuse Star Clusters in Early-type Galaxies
• Field/Isolated lenticular galaxies with high $S_N$ values: the case of NGC 4546 and its globular cluster system
• Mysterious Globular Cluster System of the Peculiar Massive Galaxy M85

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