J/MNRAS/514/5570ivo://CDS.VizieR/J/MNRAS/514/5570doi:10.26093/cds/vizier/bg-g2-5e2CDSNikitha K.J.Vig S.Ghosh S.K.2026-08-03T07:31:34Z2025-09-16T14:52:42ZCDS support team

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

cds-question@unistra.frglobular-star-clustersstellar-populationsGlobular clusters (GCs), being old and densely packed, serve as ideal laboratories to test stellar evolution theories. Although there is enormous literature on GCs in optical bands, studies in the ultraviolet (UV) regime are sparse. In this work, we study the stellar populations of a metal-poor and a rather dispersed GC, NGC 5053, using the UV instrument of AstroSat, namely the Ultra Violet Imaging Telescope in three far-UV (F154W, F169M, F172M) and three near-UV (N219M, N245M, N263M) filters. Photometry was carried out on these images to construct a catalogue of UV stars, of which the cluster members were identified using Gaia EDR3 catalogue. UV and optical colour-magnitude diagrams (CMDs) help us locate known stellar populations such as blue horizontal branch stars, RR-Lyrae stars, red horizontal branch stars, blue straggler stars (BSSs), SX-Phe, red giant branch, and AGB stars. Based on their locations in the CMDs, we have identified eight new BSS candidates, six probable eBSSs, and an extreme horizontal branch candidate. Their nature has been confirmed by fitting their spectral energy distributions (SEDs) with stellar atmospheric models. We believe the BSS population of this cluster is likely to have a collisional origin based on our analyses of their radial distribution and SEDs. BaSTI-IAC isochrones were generated to characterize the cluster properties, and we find that the observed brightness and colours of cluster members are best fit with a model that is {alpha}-enhanced with Y = 0.247, [Fe/H] = -1.9, and age = 12.5 +/- 2.0 Gyr.2022MNRAS.514.5570Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/514/5570CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/350 : Gaia EDR3 (Gaia Collaboration, 2020)I/337 : Gaia DR1 (Gaia Collaboration, 2016)J/MNRAS/505/5978 : Gaia EDR3 view on Galactic globular clustersJ/AJ/143/121 : UV properties of Galactic globulars with GALEX.J/ApJS/237/18 : Cr, Co, and Ni abundances for metal-poor red giantsJ/ApJ/819/135 : Lithium-rich giants in globular clusters (Kirby+, 2016)J/ApJ/804/109 : Equivalent widths of RGB stars in NGC 5053 (Boberg+, 2015)J/A+A/579/A104 : Abundances in NGC 5053 and NGC 5634 (Sbordone+, 2015)B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+,2016)II/312 : GALEX-DR5 (GR5) sources from AIS and MIS (Bianchi+ 2011)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/514/5570https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/514/5570http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/514/5570https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/514/5570https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/514/5570http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/514/5570GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/514/5570/tablea1 (UVIT photometric catalogue of NGC 5053 for detected stars in images)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/514/5570/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/514/5570/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/514/5570/tablea1?GETtext/xml+votable180.050000true199.160517.61680.0055555555555555566/27973 27975 27984 27986https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/514/5570?format=asciidefaultJ/MNRAS/514/5570/tablea1UVIT photometric catalogue of NGC 5053 for detected stars in imagesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDIdentifier star numbermeta.id;meta.mainintRAJ2000Right ascension (J2000) (RA)degpos.eq.ra;meta.mainDEJ2000Declination (J2000) (Dec)degpos.eq.dec;meta.mainNUVB4mag? AB magnitude corrected for reddening in NUV B4 band centered on 263.2nm with 27.5nm bandwidth (N263M)magphot.mag;em.UV.200-300nmfloatnullableNUVB15mag? AB magnitude corrected for reddening in NUV B15 band centered on 219.6nm with 27.0nm bandwidth (N219M)magphot.mag;em.UV.200-300nmfloatnullableNUVB13mag? AB magnitude corrected for reddening in NUV B13 band centered on 244.7nm with 28.0nm bandwidth (N245M)magphot.mag;em.UV.200-300nmfloatnullableF154Wmag? AB magnitude corrected for reddening in FUV F154W band centered on 154.1nm with 38.0nm bandwidth (F154W)magphot.mag;em.UV.100-200nmfloatnullableF169Mmag? AB magnitude corrected for reddening in FUV F169M band centered on 160.8nm with 29.0nm bandwidth (F169M)magphot.mag;em.UV.100-200nmfloatnullableF172Mmag? AB magnitude corrected for reddening in FUV F172M band centered on 171.7nm with 12.5nm bandwidth (F172M)magphot.mag;em.UV.100-200nmfloatnullableDelta? Positional difference between the UVIT source and the GaiaeDR3 counterpart ({Delta})arcsecpos.angDistance;arith.difffloatnullableTypeThe nature of the source (Source) (1)src.classcharGaiaEDR3Display the GaiaEDR3 data Cat. I/350meta.ref.urlchar