J/ApJ/887/82ivo://CDS.VizieR/J/ApJ/887/82doi:10.26093/cds/vizier.18870082CDSKraemer K.E.Sloan G.C.Keller L.D.McDonald I.Zijlstra A.A.,Groenewegen M.A.T.2021-07-05T12:55:36Z2021-06-10T12:30:49ZCDS support team

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

cds-question@unistra.frcarbon-starsinfrared-astronomyspectroscopytwo-color-diagramsNew infrared spectra of 33 Galactic carbon stars from FORCAST on SOFIA reveal strong connections between stellar pulsations and the dust and molecular chemistry in their circumstellar shells. A sharp boundary in overall dust content, which predominantly measures the amount of amorphous carbon, separates the semiregular and Mira variables, with the semiregulars showing little dust in their spectra and the Miras showing more. In semiregulars, the contribution from SiC dust increases rapidly as the overall dust content grows, but in Miras, the SiC dust feature grows weaker as more dust is added. A similar dichotomy is found with the absorption band from CS at ~7.3{mu}m, which is generally limited to semiregular variables. Observationally, these differences make it straightforward to distinguish semiregular and Mira variables spectroscopically without the need for long-term photometric observations or knowledge of their distances. The rapid onset of strong SiC emission in Galactic carbon stars in semiregular variables points to a different dust-condensation process before strong pulsations take over. The break in the production of amorphous carbon between semiregulars and Miras seen in the Galactic sample is also evident in Magellanic carbon stars, linking strong pulsations in carbon stars to the strong mass-loss rates which will end their lives as stars across a wide range of metallicities.2019ApJ...887...82Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/887/82CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)III/227 : General Catalog of galactic Carbon stars, 3d Ed. (Alksnis+ 2001)J/AJ/132/2268 : SAGE calibration stars (Meixner+, 2006)J/MNRAS/369/751 : Near-infrared photometry of carbon stars (Whitelock+, 2006)J/MNRAS/376/313 : Carbon star in Magellanic Cloud (Groenewegen+, 2007)J/AcA/59/239 : VI LCs of LMC long-period variables (Soszynski+, 2009)J/AJ/142/103 : Cool evolved stars in SAGE-SMC and SAGE-LMC (Boyer+, 2011)J/AcA/61/217 : VI LCs of SMC long-period variables (Soszynski+, 2011)J/A+A/566/A95 : C-rich giants synthetic spectrophotom. IV (Eriksson+, 2014)J/MNRAS/449/639 : VMC survey. XIV. SFR in SMC (Rubele+, 2015)J/ApJ/826/44 : Spitzer/IRS obs. of Magellanic carbon stars (Sloan+, 2016)J/A+A/609/A114 : Local Group AGB stars & red supergiants (Groenewegen+, 2018)J/A+A/629/A94 : CO spectra of 49 semi-regular variables (Diaz-Luis+, 2019)J/A+A/628/A62 : Spectra of 25 carbon star envelopes (Massalkhi+, 2019)J/A+A/622/A120 : Mass loss from Miras with and without Tc (Uttenthaler, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/887/82https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/887/82http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/887/82https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/887/82https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/887/82http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/887/82GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/887/82/targets (SOFIA/FORCAST targets (Table 1) and dust properties (Table 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/82/targets?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/82/targets?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/82/targets?GETtext/xml+votable180.050000true0.316083360.35527780.005555555555555556Cone search capability for table J/ApJ/887/82/table5 (Revised feature strengths - SWS sample (Sloan+, 2016, J/ApJ/826/44/table6))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/82/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/82/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/82/table5?GETtext/xml+votable180.050000true0.316069760.35528420.005555555555555556Cone search capability for table J/ApJ/887/82/table6 (Revised feature strengths - IRS sample (Sloan+, 2016, J/ApJ/826/44/cstars))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/82/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/82/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/82/table6?GETtext/xml+votable180.050000true8.9052628-73.16561560.0055555555555555565/8263 8269 8272 8274 8280 8281 8329 6/1727 2740 2920 3050 3255 3287 3438 3459 3766 4347 4365 4693 5273 6714 9783 10103 10960 11928 13677 13861 13875 14447 14600 14809 14894 15401 15421 15444 15641 16144 16157 16233 19490 19629 21224 21338 21425 22239 22941 23548 23606 23640 24158 24350 24361 24501 26289 26319 26654 29222 29286 29531 29558 29855 29886 30212 30265 30521 30593 30603 32189 32331 33043 33046 33051 33062 33072 33075 33080 33081 33082 33084 33087 33092 33093 33094 33100 33101 33102 33104 33105 33107 33110 33112 33113 33114 33116 33117 33132 33133 33138 33293 33294 33295 33304 33306 35641 36369 37210 37544 37719 39396 39417 40150 41530 41760 41849 42347 43581 46729 487001.6553710307751707e-20 1.6553710307751707e-20https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/887/82?format=asciiInfrareddefaultJ/ApJ/887/82/targetsSOFIA/FORCAST targets (Table 1) and dust properties (Table 2)Group[1/3] Group (G1)meta.codeintr_PerReference on Per (2)meta.ref;pos.framecharPerPerioddtime.periodintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharf_NameFlag on Name (1)meta.codecharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainDateDate of observation (UT)time.epochnullableu_Per[:] Uncertainty flag on Permeta.code.errorcharF12[44/47530] F_v_ at 12umJyphot.flux.density;em.IR.8-15umintSimbadSimbad column added by the CDSmeta.ref.urlchar6-9um[0.069/1.6] The ([6]-[9]) color indexmagphot.color;em.IR;em.IRfloatnullablee_6-9um[0.002/0.015] 6-9um uncertaintymagstat.errorfloatnullableFSiC[-0.021/0.4] SiC flux relative to the continuumphot.flux;arith.ratiofloatnullablee_FSiC[0.002/0.02] FSiC uncertaintystat.errorfloatnullablelamC[11.19/11.98] {lambda}_C_ value (1)umem.wlfloatnullablee_lamC[0.01/0.2] LamC uncertaintyumstat.errorfloatnullablelogDPR[-8.8/-6.4] Log of the dust production ratesolMass/yrphys.mass.lossfloatnullableClass[1/5] CE class from Sloan+, 2016, J/ApJ/826/44meta.codeintnullableJ/ApJ/887/82/table5Revised feature strengths - SWS sample (Sloan+, 2016, J/ApJ/826/44/table6)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameTarget identifiermeta.id;meta.maincharFSiC1[-0.18/2.9] SiC flux relative to the continuum - This workphot.flux;arith.ratiofloate_FSiC1[0/0.09] Uncertainty in FSiC1stat.errorfloatFSiC2[-0.16/3.1] SiC flux relative to the continuum - S16 (Sloan+, 2016, J/ApJ/826/44)phot.flux;arith.ratiofloate_FSiC2[0/0.09] Uncertainty in FSiC2stat.errorfloatColor1[-0.15/0.5] The ([6]-[9]) color - This workmagphot.color;em.IR;em.IRfloate_Color1[0.001/0.05] Uncertainty in Color1magstat.errorfloatColor2[-0.16/0.6] The ([6]-[9]) color - S16magphot.color;em.IR;em.IRfloate_Color2[0.001/0.04] Uncertainty in Color2magstat.errorfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_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.mainJ/ApJ/887/82/table6Revised feature strengths - IRS sample (Sloan+, 2016, J/ApJ/826/44/cstars)SimbadNameSimbad column added by the CDSmeta.idcharNameTarget identifiermeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFSiC1[-0.18/2.9] SiC flux relative to the continuum - This workphot.flux;arith.ratiofloate_FSiC1[0/0.09] Uncertainty in FSiC1stat.errorfloatFSiC2[-0.16/3.1] SiC flux relative to the continuum - S16 (Sloan+, 2016, J/ApJ/826/44)phot.flux;arith.ratiofloate_FSiC2[0/0.09] Uncertainty in FSiC2stat.errorfloatColor1[-0.15/0.5] The ([6]-[9]) color - This workmagphot.color;em.IR;em.IRfloate_Color1[0.001/0.05] Uncertainty in Color1magstat.errorfloatColor2[-0.16/0.6] The ([6]-[9]) color - S16magphot.color;em.IR;em.IRfloate_Color2[0.001/0.04] Uncertainty in Color2magstat.errorfloat_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