J/AJ/170/85ivo://CDS.VizieR/J/AJ/170/85CDSAsa'd R.Coelho P.R.T.John J.M.Chilingarian I.V.Bruzual G.,Charlot S.2026-06-09T09:47:06Z2026-06-09T10:16:55ZCDS support team

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

cds-question@unistra.frglobular-star-clustersmetallicityastronomical-modelsvisible-astronomyspectroscopystellar-populationsStellar population synthesis (SPS) models are a key tool for deriving the age, metallicity, radial velocity, and reddening of star clusters from their integrated spectra. Using a sample of 129 star clusters with high-quality spectra, we analyze the uncertainties associated with selecting an empirical versus a theoretical stellar spectral library in the SPS models. We find that the fits from the different models agree on the goodness-of-fit metrics and inferred reddening. However, the derived age and metallicity can be affected by the choice of the stellar library, with synthetic libraries tending to give lower age and metallicity, especially for spectra with low signal-to-noise ratio. Ages and reddening values from SSP-equivalent fits are consistent with the multipopulation fits; however, SSP-equivalent metallicities are affected by the coarse coverage of the SPS grid in [Fe/H]. When comparing the spectral fitting results with the literature, we find that (1) all models underestimate age for old and metal-poor systems, and (2) on average, SPS models based on synthetic stellar libraries better match the isochrone ages and metallicities from high-resolution stellar spectroscopy.2025AJ....170...85Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/170/85CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVI/120 : High-resolution synthetic stellar library (Coelho+, 2005)VI/157 : Full-spectrum fitting of simple stellar pop. (Goudfrooij+, 2021)J/A+A/333/231 : O-M stars model atmospheres (Bessell+ 1998)J/A+A/442/281 : Late-type giants BVRIJHKL & Teff calibration (Kucinskas+, 2005)J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)J/MNRAS/374/664 : Stellar atmosph. parameters in MILES library (Cenarro+, 2007)J/MNRAS/404/1639 : MILES base models & new line index system (Vazdekis+, 2010)J/A+A/547/A108 : Comparative modelling of cool giants spect. (Lebzelter+, 2012)J/MNRAS/435/952 : Lick indices for 51 stars (Sansom+, 2013)J/MNRAS/491/2025 : Synthetic stellar spectra in SPS models (Coelho+, 2020)J/MNRAS/499/2327 : Ages and abundances from spectral fitting (Goncalves+, 2020)J/MNRAS/505/979 : Model spectra for identifying age spreads (Asa'd +, 2021)J/A+A/672/A161 : Photometry of 101 Magellanic Cloud clusters (Milone+, 2023)J/ApJ/824/5 : Chemical abundances in NGC 5024 (M53) (Boberg+, 2016)J/A+A/583/A69 : NGC 6139 BV photometry (Bragaglia+, 2015)J/A+A/505/139 : Abund. of red giants in 17 globular clusters (Carretta+, 2009)J/A+A/505/117 : Abund. of red giants in 15 globular clusters (Carretta+, 2009)J/A+A/533/A69 : Spectroscopy of 124 RGB stars in NGC 1851 (Carretta+, 2011)J/A+A/557/A138 : Detailed chemical abund. in the GlC NGC 362 (Carretta+ 2013)J/A+A/578/A116 : Abund. of red giant stars in NGC6093 (M80) (Carretta+, 2015)J/A+A/600/A118 : Abund. of red giant stars in NGC6093 (M80) (Carretta+, 2017)J/AJ/129/1607 : Equivalent widths of 4 RGB in NGC 7492 (Cohen+, 2005)J/ApJ/834/105 : High-resolution GC abundances. II. (Colucci+, 2017)J/AJ/136/1703 : Ridgelines of six intermediate-age SMC clusters (Glatt+, 2008)J/A+A/345/430 : Abundances of 6 cool supergiants in NGC 330 (Hill, 1999)J/MNRAS/377/300 : CT1 photometry in 6 SMC star clusters (Piatti+, 2007)J/A+A/672/A161 : Photometry of 101 Magellanic Cloud clusters (Milone+, 2023)J/AJ/116/2395 : BV photometry in five SMC clusters (Mighell+, 1998)J/ApJS/161/304 : Star clusters in the MW and satellites (McLaughlin+, 2005)J/AJ/136/375 : Chemical composition of LMC red giants (Mucciarelli+, 2008)J/ApJ/717/277 : Chemical composition of old LMC clusters (Mucciarelli+, 2010)J/AJ/139/878 : RGB stars in 8 LMC clusters (Sharma+, 2010)J/MNRAS/300/665 : HST VI phot. of Six LMC Old Globular Clusters (Olsen+ 1998)J/ApJ/297/582 : NGC 2213 BR photometry (Da Costa+, 1985)J/ApJ/663/296 : UBV(RI)c phot. of NGC5139 subgiants (Villanova+, 2007)J/MNRAS/450/815 : Red giants in NGC 5286 (Marino+, 2015)J/ApJ/813/97 : M62 (NGC 6266) giant branch stars abundances (Lapenna+, 2015)J/ApJ/834/105 : High-resolution GC abundances. II. (Colucci+, 2017)J/ApJ/846/23 : High-res. spectra of 9 RGB stars in NGC6681 (O'Malley+, 2017)J/MNRAS/434/358 : 4 Galactic globular clusters Fe line depths (Sakari+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/170/85https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/170/85http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/170/85https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/170/85https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/170/85http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/170/85GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/170/85/fig1 (Age and metallicity of the star clusters used in this work (Data behind Figure 1))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/170/85/fig1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/170/85/fig1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/170/85/fig1?GETtext/xml+votable180.050000true90.51384-60.523790.0055555555555555565/8280 6/10336 12405 12425 12531 12943 19091 21017 24843 25873 27981 28067 28705 28741 28751 28769 28778 28882 28959 28973 29184 29187 29195 29216 29222 29267 29289 29294 29377 30769 31019 31115 31417 32953 33045 33047 33052 33077 33079-33080 33088 33091 33093-33094 33096 33098-33100 33104-33105 33112-33113 33124-33125 33127 33137-33138 33140 33294-33295 33304 33306 33317 33320-33321 33323 33328 33330 33635 33793 34242 35969 37294 37386 37410 37504 37516 37537 38465 38922 38954 41304 41522 41852 42076 42278 42314 42700 42761 42841 42955 42990 43125 43227 44086 44220 47125 47620 47777 47825 47866 47868 47971 48035 48434 48698https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/170/85?format=asciiOpticaldefaultJ/AJ/170/85/fig1Age and metallicity of the star clusters used in this work (Data behind Figure 1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyHost galaxy (1)meta.id.parentcharTelTelescope (2)meta.id;instr.telcharAV-Sy-SSP[-0.1/3.34] Simple Stellar Population (SSP) extinction from SynCoMiL librarymagphys.absorptionfloatSimbadNameSimbad column added by the CDSmeta.idcharnullable[Fe/H]Lit[-2.38/0.03]? Log Fe/H abundance from literaturephys.abund.Fefloatnullabler_[Fe/H]LitReference for [Fe/H]Litmeta.ref;phys.abund.FecharAge-Lit[0.01/13.6]? Age from literatureGyrtime.agefloatnullabler_Age-LitReference for Age-Litmeta.ref;time.agecharbibAge-LitReference bibcode for Age-Lit (column added by CDS)meta.bib.bibcode;time.agecharAV-CBC[-0.1/3.5] Mean extinction from Coelho14ext librarymagphys.absorptionfloatFig2Spectral fit to the object's SED in JPG format (Figure 2 of the paper)meta.ref.urlchare_AV-CBC[0.1/0.3]? Uncertainty in AV-Coelho14ext librarymagstat.error;phys.absorptionfloatnullableAge-CBC[0.01/13.25] Mean age from Coelho14ext libraryGyrtime.agefloate_Age-CBC[0.002/0.4] Uncertainty in Age-CBCGyrstat.error;time.agefloat[Fe/H]CBC[-1.92/-0.09] Mean [Fe/H] from Coelho14ext libraryphys.abund.Fe;stat.meanfloate_[Fe/H]CBC[0.02/0.5] Uncertainty in [Fe/H]CBCstat.error;phys.abund.FefloatAV-CBC-SSP[-0.1/3.32] Simple Stellar Population (SSP) extinction from Coelho14ext librarymagphys.absorptionfloatAge-CBC-SSP[0.01/14] Simple Stellar Population (SSP) age from Coelho14ext libraryGyrtime.agefloat[Fe/H]CBC-SSP[-1.92/0.25] Simple Stellar Population (SSP) [Fe/H] from Coelho14ext libraryphys.abund.FefloatAV-M[-0.1/3.5] Mean extinction from MILES librarymagphys.absorptionfloate_AV-M[0.1/0.3]? Uncertainty in AV-Mmagstat.error;phys.absorptionfloatnullableAge-M[0/11.91] Mean age from MILES libraryGyrtime.agefloate_Age-M[0.002/0.4] Uncertainty in Age-MGyrstat.error;time.agefloat[Fe/H]M[-1.8/0.03] Mean [Fe/H] from MILES libraryphys.abund.Fe;stat.meanfloate_[Fe/H]M[0.02/0.5] Uncertainty in [Fe/H]Mstat.error;phys.abund.FefloatAV-M-SSP[-0.1/3.22] Simple Stellar Population (SSP) extinction from MILES librarymagphys.absorptionfloatAge-M-SSP[0.001/14] Simple Stellar Population (SSP) age from MILES libraryGyrtime.agefloat[Fe/H]M-SSP[-1.92/0.25] Simple Stellar Population (SSP) [Fe/H] from MILES libraryphys.abund.FefloatAV-Sy[-0.1/3.5] Mean extinction from SynCoMiL librarymagphys.absorptionfloate_AV-Sy[0.1/0.3]? Uncertainty in AV-Symagstat.error;phys.absorptionfloatnullableAge-Sy[0/13.54] Mean age from SynCoMiL libraryGyrtime.agefloate_Age-Sy[0.002/0.4] Uncertainty in Age-SyGyrstat.error;time.agefloat[Fe/H]Sy[-1.89/0.03] Mean [Fe/H] from SynCoMiL libraryphys.abund.Fe;stat.meanfloate_[Fe/H]Sy[0.02/0.5] Uncertainty in [Fe/H]Systat.error;phys.abund.FefloatAge-Sy-SSP[0.01/14] Simple Stellar Population (SSP) age from SynCoMiL libraryGyrtime.agefloat[Fe/H]Sy-SSP[-1.92/0.25] Simple Stellar Population (SSP) [Fe/H] from SynCoMiL libraryphys.abund.Fefloat_RAPositions from Simbad (right ascension part)degpos.eq.ra;meta.main_DEPositions from Simbad (declination part)degpos.eq.dec;meta.mainClusterCluster namemeta.id;meta.maincharbib[Fe/H]LitReference bibcode for [Fe/H]Lit (column added by CDS)meta.bib.bibcode;phys.abund.Fechar