J/ApJ/900/L43ivo://CDS.VizieR/J/ApJ/900/L43doi:10.26093/cds/vizier.19009043CDSLewis H.M.Anguiano B.Stassun K.G.Majewski S.R.Arras P.,Sarazin C.L.Li Z.-Y.De Lee N.Troup N.W.Allende Prieto C.A.,Badenes C.Cunha K.Garcia-Hernandez D.A.Nidever D.L.Palicio P.A.,Simon J.D.Smith V.V.2022-08-25T11:38:50Z2022-02-15T13:44:25ZCDS support team

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

cds-question@unistra.frmultiple-starsradial-velocitycarbon-starswhite-dwarf-starsinfrared-astronomyspectroscopyDraco C1 is a known symbiotic binary star system composed of a carbon red giant and a hot, compact companion-likely a white dwarf-belonging to the Draco dwarf spheroidal galaxy. From near-infrared spectroscopic observations taken by the Apache Point Observatory Galactic Evolution Experiment (APOGEE-2), part of Sloan Digital Sky Survey IV, we provide updated stellar parameters for the cool, giant component, and constrain the temperature and mass of the hot, compact companion. Prior measurements of the periodicity of the system, based on only a few epochs of radial velocity data or relatively short baseline photometric observations, were sufficient only to place lower limits on the orbital period (P>300d). For the first time, we report precise orbital parameters for the binary system: with 43 radial velocity measurements from APOGEE spanning an observational baseline of more than 3yr, we definitively derive the period of the system to be 1220.0_-3.5_^+3.7^days. Based on the newly derived orbital period and separation of the system, together with estimates of the radius of the red giant star, we find that the hot companion must be accreting matter from the dense wind of its evolved companion.2020ApJ...900L..43Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/900/L43CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/mk : Catalogue of Stellar Spectral Classifications (Skiff, 2009-)B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)J/AJ/110/2131 : M/L for Draco and UMi. I. (Armandroff+ 1995)J/A+AS/146/407 : Symbiotic stars catalogue (Belczynski+, 2000)J/AJ/124/1651 : Faint high-latitude carbon stars SDSS phot. (Margon+, 2002)J/A+A/383/188 : Spectrophotometric atlas of symbiotic stars (Munari+, 2002)J/A+A/386/237 : UBV(RI)c photometry of 7 symbiotic stars (Munari+, 2002)J/AJ/127/2838 : Faint high-latitude carbon stars SDSS phot. (Downes+, 2004)J/MNRAS/375/831 : Draco MegaCam, INT and HST photometry (Segall+, 2007)J/AJ/136/1921 : Variable stars of Draco dSph (Kinemuchi+, 2008)J/BaltA/17/293 : Symbiotic stars multi-epoch UBV(RI)c phot. (Henden+, 2008)J/MNRAS/411/2770 : Hot white dwarfs in GALEX-DR5 (Bianchi+, 2011)J/ApJ/730/67 : Radial velocities of low-mass white dwarfs (Brown+, 2011)J/MNRAS/413/1121 : SDSS post-common envelope bin. X (Rebassa-Mansergas+ 2011)J/AN/333/242 : Recent photometry of symbiotic stars (Skopal+, 2012)J/ApJ/765/12 : Carbon stars & DQ WDs from SDSS-DR7+DR8 (Green, 2013)J/MNRAS/448/2717 : Bayesian analysis of resolved stellar sp. (Walker+, 2015)J/MNRAS/451/2735 : Four close dSph XXM observations (Manni+, 2015)J/ApJ/801/125 : Carbon in red giants in GCs and dSph galaxies (Kirby+, 2015)J/ApJ/821/54 : XMM spectral analysis of Draco dSph (Sonbas+, 2016)J/AJ/151/144 : ASPCAP weights for APOGEE chemical elements (Garcia+, 2016)J/AJ/152/180 : Bolometric fluxes of EBs in Tycho-2 (Stassun+, 2016)J/AJ/153/136 : Planets & host stars with Gaia parallaxes (Stassun+, 2017)J/AJ/156/257 : Spectroscopy of RGB stars in Draco (Spencer+, 2018)J/ApJS/240/21 : Symbiotic stars with 2MASS, WISE & Gaia data (Akras+, 2019)J/ApJ/872/43 : IR sp. of symbiotic stars. XII. V934 Her (Hinkle+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/900/L43https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/900/L43http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/900/L43https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/900/L43https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/900/L43http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/900/L43GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/ApJ/900/L43/tablea1RV measurements from APOGEErecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[57495.5/58658.33] Modified Julian date of observation (JD-2400000.5)time.epochdoubleRVel[-304.15/-294.17] Derived barycentric radial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVel[0.08/0.31] Uncertainty in RVelkm/sstat.error;spect.dopplerVelocdouble