J/MNRAS/459/1170ivo://CDS.VizieR/J/MNRAS/459/1170doi:10.26093/cds/vizier.74591170CDSScowcroft V.Seibert M.Freedman W.L.Beaton R.L.Madore B.F.,Monson A.J.Rich J.A.Rigby J.R.2024-08-16T20:16:39Z2017-09-01T10:33:31ZCDS support team

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

cds-question@unistra.frvariable-starsinfrared-photometrymetallicityWe compare mid-infrared (IR) 3.6 and 4.5{mu}m Warm Spitzer observations for Cepheids in the Milky Way and the Large and Small Magellanic Clouds. Using models, we explore in detail the effect of the CO rotation-vibration band-head at 4.6{mu}m on the mid-IR photometry. We confirm the temperature sensitivity of the CO band-head at 4.6{mu}m and find no evidence for an effect at 3.6{mu}m. We compare the ([3.6]-[4.5]) period-colour relations in the MW, LMC and SMC. The slopes of the period-colour relations for the three galaxies are in good agreement, but there is a trend in zero-point with metallicity, with the lowest metallicity Cepheids having redder mid-IR colours. Finally, we present a colour-[Fe/H] relation based on published spectroscopic metallicities. This empirical relation, calibrated to the metallicity system of Genovali et al., demonstrates that the ([3.6]-[4.5]) colour provides a reliable metallicity indicator for Cepheids, with a precision comparable to current spectroscopic determinations.2016MNRAS.459.1170Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/459/1170CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/743/76 : Spitzer photometry of LMC Cepheids (Scowcroft+, 2011)J/ApJ/759/146 : Spitzer/IRAC photometry for 37 Galactic Cepheids (Monson+ 2012)J/A+A/566/A37 : Iron abundances for 42 Galactic Cepheids (Genovali+, 2014)J/ApJ/816/49 : Spitzer/IRAC observations of SMC Cepheids (Scowcroft+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/459/1170https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/459/1170http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/459/1170https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/459/1170https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/459/1170http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/459/1170GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/459/1170/table1 (Mid-IR colours and metallicities for MW, LMC and SMC Cepheids)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/459/1170/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/459/1170/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/459/1170/table1?GETtext/xml+votable180.050000true298.11819891.00565830.0055555555555555565/8275 8280 8329 6/3045 12934 12968 12971 13201 13288 14295 14409 14625 15633 22219 23622 23922 24411 28779 28831 29081 29095 29104 29523 29665 29897 30128 30258 30321-30322 32074 32955 33001 33051-33054 33073 33075-33078 33084 33088 33091-33092 33094-33095 33098-33099 33106-33108 33110 33112-33113 33124 33126-33127 33144 33287 33294-33295 33297-33299 33304 33306-33307 33313 33328 33804 37303 37931 41461 41862 42153 42500https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/459/1170?format=asciiInfrareddefaultJ/MNRAS/459/1170/table1Mid-IR colours and metallicities for MW, LMC and SMC CepheidsSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameCepheid IDmeta.id;meta.maincharlogPPeriodlog(d)time.periodfloat[3.6]-[4.5]Mid-ID [3.6]-[4.5] colour indexmagphot.color;em.IR;em.IRfloate_[3.6]-[4.5]rms uncertainty on [3.6]-[4.5]magstat.errorfloat[Fe/H]? Metallicityphys.abund.ZfloatnullableGalGalaxy namemeta.id.parentchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main