J/ApJ/854/117ivo://CDS.VizieR/J/ApJ/854/117doi:10.26093/cds/vizier.18540117CDSJones O.C.Maclay M.T.Boyer M.L.Meixner M.McDonald I.Meskhidze H.2019-01-11T13:58:57Z2019-01-02T10:11:59ZCDS support team

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

cds-question@unistra.frgalaxiesinfrared-sourcesinfrared-photometryvisible-astronomybroad-band-photometryeffective-temperaturelate-type-starsWe present JHKs observations of the metal-poor ([Fe/H]{<}-1.40) dwarf-irregular galaxies, Leo A and Sextans A, obtained with the WIYN High-resolution Infrared Camera at Kitt Peak. Their near-IR stellar populations are characterized by using a combination of color-magnitude diagrams and by identifying long-period variable stars. We detected red giant and asymptotic giant branch stars, consistent with membership of the galaxy's intermediate-age populations (2-8Gyr old). Matching our data to broadband optical and mid-IR photometry, we determine luminosities, temperatures, and dust-production rates (DPR) for each star. We identify 32 stars in LeoA and 101 stars in Sextans A with a DPR>10^-11^M_{sun}_/yr, confirming that metal-poor stars can form substantial amounts of dust. We also find tentative evidence for oxygen-rich dust formation at low metallicity, contradicting previous models that suggest oxygen-rich dust production is inhibited in metal-poor environments. The total rates of dust injection into the interstellar medium of Leo A and Sextans A are (8.2+/-1.8)x10^-9^M_{sun}_/yr and (6.2+/-0.2)x10^-7^M_{sun}/yr, respectively. The majority of this dust is produced by a few very dusty evolved stars and does not vary strongly with metallicity.2018ApJ...854..117Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/854/117CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/AJ/123/3154 : RV light curves of variable stars in Leo A (Dolphin+, 2002)J/AJ/125/1261 : VI photometry of Sextans A Cepheids (Dolphin+, 2003)J/A+A/442/281 : Late-type giants BVRIJHKL and Teff (Kucinskas+, 2005)J/A+A/448/181 : IR colours of AGB and post-AGB stars (Groenewegen+, 2006)J/A+A/503/913 : Synthetic spectrophotom. for C-rich giants (Aringer+, 2009)J/ApJ/697/1993 : Spitzer study of AGB stars. III. (Boyer+, 2009)J/AJ/137/3139 : LMC SAGE. New variable evolved stars and YSOs (Vijh+, 2009)J/AJ/142/103 : Cool evolved stars in SAGE-SMC and SAGE-LMC (Boyer+, 2011)J/A+A/532/A54 : GRAMS carbon-star model grid (Srinivasan+, 2011)J/AJ/143/74 : HST photometry in 6 dwarf galaxies (Bianchi+, 2012)J/MNRAS/427/3209 : Galactic and MC O-AGBs and RSGs stars (Jones+, 2012)J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)J/MNRAS/427/2647 : Sgr dSph stars spectral classification (McDonald+, 2012)J/ApJ/753/71 : Mass-loss return from LMC evolved stars. VI. (Riebel+, 2012)J/A+A/540/A135 : AGB population of NGC 6822 (Sibbons+, 2012)J/A+A/566/A44 : gr photometry of Sextans A and Sextans B (Bellazzini+, 2014)J/MNRAS/440/631 : IR photometry of LMC O-rich evolved stars (Jones+, 2014)J/ApJS/214/19 : Suprime-Cam wide-field photometry of Leo A (Stonkute+, 2014)J/ApJ/789/147 : Star formation histories of LG dwarf galaxies (Weisz+, 2014)J/ApJ/810/116 : S-type AGB stars in SMC (Boyer+, 2015)J/ApJS/216/10 : DUSTiNGS. I. The Good Source Catalog (Boyer+, 2015)J/ApJ/800/51 : DUSTiNGS II. Metal-poor dusty AGB stars (Boyer+, 2015)J/MNRAS/457/2814 : SAGE SMC evolved stars candidates (Srinivasan+, 2016)J/ApJ/834/9 : Spectroscopy of LeoA, Aqr & Sgr dwarf gal. (Kirby+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/854/117https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/854/117http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/854/117https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/854/117https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/854/117http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/854/117GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/854/117/table1 (*Sextans A and Leo A parameters adopted in this work)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/854/117/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/854/117/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/854/117/table1?GETtext/xml+votable180.050000true152.753333-4.6927780.005555555555555556Cone search capability for table J/ApJ/854/117/table6 (Catalog of point sources for Leo A and Sextans A)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/854/117/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/854/117/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/854/117/table6?GETtext/xml+votable180.050000true149.892830.7250.0055555555555555566/5287 5293 268582.0616683193919197e-20 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/854/117?format=asciiInfraredOpticaldefaultJ/ApJ/854/117/table1*Sextans A and Leo A parameters adopted in this workSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalGalaxy namemeta.id;meta.maincharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainDist[789/1432] Distancekpcpos.distance;pos.heliocentricinte_Dist[44/53] Distance uncertaintykpcstat.errorintm-M[24.51/25.6] Distance modulusmagphot.mag.distModfloate_m-M[0.1/0.2] m-M uncertaintymagstat.errorfloat[Fe/H]Metallicityphys.abund.Zfloatf_[Fe/H][b] b: Kirby et al. (2017, J/ApJ/834/9)meta.codecharRh[2.1/2.5] Half-light Radiusarcminphys.angSizefloatM*[6/44] Stellar Mass1e+06solMassphys.massintE(B-V)[0.02/0.05] Color excessmagphot.color.excessfloatITRGB[20.5/21.8] Tip of the red giant branch (TRGB) in I-bandmagphot.mag;em.opt.IfloatDPRTotBest-fitting chemical type total dust-production rate (from Table 10)solMass/yrphys.mass.lossdoublee_DPRTotDPRTot uncertaintysolMass/yrstat.errordoubleDPRMedBest-fitting chemical type median dust-production rate (from Table 10)solMass/yrphys.mass.lossdoubleNsNumber of sources for this galaxy (link to Table 6)meta.numberintnullableNEDNED column added by the CDSmeta.ref.urlcharJ/ApJ/854/117/table6Catalog of point sources for Leo A and Sextans AGalGalaxy identifiermeta.id.parentcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[0/491] Point source identifier within Galmeta.id;meta.mainintRAJ2000[149.8/152.8] Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[-4.8/30.8] Declination (J2000)degpos.eq.dec;meta.mainUmag[18/23.2]? U band magnitudemagphot.mag;em.opt.UfloatnullableBmag[17.2/27.1]? B band magnitudemagphot.mag;em.opt.BfloatnullableVmag[16.4/26.6]? V band magnitudemagphot.mag;em.opt.VfloatnullableImag[16.7/24.6]? I band magnitudemagphot.mag;em.opt.IfloatnullableJmag[13.4/21]? WIYN/WHIRC J band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.04/0.1]? 1{sigma} uncertainty in Jmagmagstat.error;phot.mag;em.IR.JfloatnullableHmag[13.3/19.8]? WIYN/WHIRC H band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag[0.04/0.1]? 1{sigma} uncertainty in Hmagmagstat.error;phot.mag;em.IR.HfloatnullableKsmag[13/19.2]? WIYN/WHIRC Ks band magnitudemagphot.mag;em.IR.Kfloatnullablee_Ksmag[0.04/0.1]? 1{sigma} uncertainty in Ksmagmagstat.error;phot.mag;em.IR.Kfloatnullable3.6mag[12.9/20.7]? Spitzer/IRAC 3.6um magnitudemagphot.mag;em.IR.3-4umfloatnullable4.5mag[13/20.5]? Spitzer/IRAC 4.5um magnitudemagphot.mag;em.IR.4-8umfloatnullable5.8mag[13/18.4]? Spitzer/IRAC 5.8um magnitudemagphot.flux.density;em.IR.4-8umfloatnullable8.0mag[13/17.4]? Spitzer/IRAC 8.0um magnitudemagphot.flux.density;em.IR.8-15umfloatnullableVar[0/1] Variable code (1=variable; 0=not variable)meta.codeintPCatDisplay data from Bianchi+, 2012, J/AJ/143/74 ; Bellazzini+, 2014, J/A+A/566/A44 ; Stonkute+, 2014, J/ApJS/214/19 and Boyer+ 2009, J/ApJ/697/1993 and 2015, J/ApJS/216/10 within 0.6"meta.ref.urlintnullableDPRDisplay the dust production rate data for this evolved star (link to Table 9)meta.ref.urlintnullableJ/ApJ/854/117/table9Luminosities and dust-production rates of the 443 evolved starsMbol[-11.4/-2.2]? Bolometric magnitudemagphys.magAbs.bolfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalGalaxy identifiermeta.id.parentcharID[0/487] The WIYN High-resolution Infrared Camera (WHIRC) identifiermeta.id;meta.mainintTeff[1200/7900]? Effective temperatureKphys.temperature.effectiveintnullableDPR[6.4e-14/5.5e-07] Dust Production RatesolMass/yrphys.mass.lossfloate_DPR[1.1e-12/4.2e-09] 1{sigma} uncertainty in DPRsolMass/yrstat.errorfloatGRAMSGRAMS model chemistry (C=Carbon; O=Oxygen)meta.codechar