J/A+A/694/A231ivo://CDS.VizieR/J/A+A/694/A231doi:10.26093/cds/vizier.36940231CDSLonare P.Cantiello M.Mirabile M.Spavone M.Rejkuba M.Hilker M.,Habas R.Iodice E.Hazra N.Riccio G.2025-05-21T20:01:44Z2025-02-18T09:04:39ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frsurveysgalaxiesglobular-star-clustersvisible-astronomysloan-photometryGlobular clusters (GCs) represent a valuable tool as a fossil tracer of the formation and evolution of galaxies and their environment. As such, studying the properties of these stellar systems provides crucial insights into the past formation and interaction events of the galaxies, especially in galaxy group and cluster environments. We study the properties of globular cluster (GC) candidates in an area of 1.25x1.03 sq. degrees centred on the NGC 5018 group of galaxies using the deep, wide field and multi-passband (ugr) observations obtained with the VLT Survey Telescope (VST) as part of the VST Elliptical Galaxy Survey (VEGAS). With a focus on studying small stellar systems (SSS) associated with bright galaxies, this paper is a continuation of the VEGAS-SSS series to investigate the GCs in the NGC 5018 group. We derived photometric catalogues of compact and extended sources in the area and identified GC candidates using a set of photometric and morphometric selection parameters. A GC candidates catalogue is provided and is inspected using a statistical background decontamination technique, benefiting from the wide area coverage of the data. The 2D distribution map of GC candidates reveals an overdensity of sources on the brightest member of the group, NGC 5018. No significant GC overdensities are observed in the other bright galaxies of the group. We report the discovery of a candidate local nucleated LSB dwarf galaxy that is possibly in tidal interaction with NGC 5018. The 2D map also reveals an intra-group GC population aligning with the bright galaxies and along the intra-group light (IGL) component of the group. The radial density profile of GC candidates in NGC 5018 follows the galaxy surface brightness profile. The (g-r) colour profile of GC candidates centred on this galaxy shows no evidence of the well-known colour bimodality, which is instead observed in the intra-group population. From the GC luminosity function (GCLF) analysis, we find a low specific frequency S_N_=0.59+/-0.27 for NGC 5018, consistent with previous results based on less deep optical data over a smaller area. This relatively low S_N and the lack of colour bimodality might be due to a combination of observational data limitations and the post-merger status of NGC 5018, which might host a population of relatively young GCs. For the intra-group GC population, we obtain a lower limit of S_N,gr_~0.6. Using the GCLF as a distance indicator, we estimate that NGC 5018 is located 38.0+/-7.9Mpc away, consistent with values in the literature.2025A&A...694A.231Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/694/A231CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/694/A231https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/694/A231http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/694/A231https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/694/A231https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/694/A231http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/694/A231GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/694/A231/catalog (Catalogue of globular cluster candidates in the observed field (table B1))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A231/catalog?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A231/catalog?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A231/catalog?GETtext/xml+votable180.050000true198.9098991-19.87488460.0055555555555555565/6230 6/https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/694/A231?format=asciiOpticaldefaultJ/A+A/694/A231/catalogCatalogue of globular cluster candidates in the observed field (table B1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedumag? Apparent magnitude in u-band within 19.04 pixels diametermagphot.mag;em.opt.Udoublenullablee_umag? Error in magnitude in u-bandmagstat.error;phot.magfloatnullablegmagApparent magnitude in g-band within 19.04 pixels diametermagphot.mag;em.opt.Bdoublee_gmagError in magnitude in g-bandmagstat.error;phot.magfloatrmagApparent magnitude in r-band within 19.04 pixels diametermagphot.mag;em.opt.Rdoublee_rmagError in magnitude in r-bandmagstat.error;phot.magfloatCIu? Concentration index in u-band (Difference between apparent magnitude within 8 and 19.04 pixels diameter)magphys.size;arith.ratiodoublenullableCIgConcentration index in g-band (Difference between apparent magnitude within 8 and 19.04 pixels diameter)magphys.size;arith.ratiodoubleCIrConcentration index in r-band (Difference between apparent magnitude within 8 and 19.04 pixels diameter)magphys.size;arith.ratiodoubleElongu? Elongation in u-band (major/minor axis)phys.size.axisRationullableElonggElongation in g-band (major/minor axis)phys.size.axisRatioElongrElongation in r-band (major/minor axis)phys.size.axisRatio