J/ApJ/769/66ivo://CDS.VizieR/J/ApJ/769/66doi:10.26093/cds/vizier.17690066CDSBrown W.R.Kilic M.Allende Prieto C.Gianninas A.Kenyon S.J.2017-06-12T08:25:13Z2015-01-13T07:58:51ZCDS support team

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

cds-question@unistra.frwhite-dwarf-starsradial-velocitystellar-distancestellar-massesvisible-astronomysloan-photometryWe present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P<=1 day) binaries. Our sample includes four objects with remarkable logg=~5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10Gyr. Four have >~0.9M_{sun}_ companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the Extremely low mass (ELM) Survey to 54; 31 of these binaries will merge within a Hubble time.2013ApJ...769...66Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/769/66CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)J/A+A/547/A96 : Low-mass He-core WDs seismic properties (Corsico+, 2012)J/ApJ/751/55 : MMT hypervelocity star survey. II. (Brown+, 2012)J/ApJ/743/138 : Spectroscopic survey of bright WDs (Gianninas+, 2011)J/A+A/536/A43 : SDSS WD main-sequence binaries (Nebot Gomez-Moran+, 2011)J/ApJ/723/1072 : The ELM survey. I. Low-mass white dwarfs (Brown+, 2010)J/MNRAS/402/620 : SDSS WD main-sequence binaries (Rebassa-Mansergas+, 2010)J/A+A/513/L7 : Post common envelope binaries from SDSS (Schreiber+, 2010)J/AJ/136/2070 : SEGUE stellar parameter pipeline III. (Allende Prieto+, 2008)J/ApJ/671/1708 : Hypervelocity stars. III (Brown+, 2007)J/ApJ/647/303 : Spectroscopic survey of hypervelocity stars (Brown+, 2006)J/ApJS/156/47 : DA WDs from the Palomar Green Survey (Liebert+, 2005)J/AJ/124/1118 : RVs of high-velocity white dwarfs (Silvestri+, 2002)J/ApJ/419/596 : Pop I UV radiation models (Dorman+, 1993)http://www.sdss.org/ : SDSS home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/769/66https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/769/66http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/769/66https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/769/66https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/769/66http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/769/66GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/769/66/wdbin (White dwarf physical parameters and binary orbital parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/769/66/wdbin?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/769/66/wdbin?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/769/66/wdbin?GETtext/xml+votable180.050000true14.20096667-6.194894440.0055555555555555566/4673 4813 5446 6015 6633 9376 12368 16973 17936 21587 21900 21961 27019 27475 27698 28054 31435https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/769/66?format=asciiOpticaldefaultJ/ApJ/769/66/table4Radial velocity measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameWhite dwarf identifier (JHHMM+DDMM)meta.id;meta.maincharHJDHeliocentric Julian Date of observation; HJD-2450000dtime.epochdoubleHRV[-404/498] Heliocentric velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HRV[3.8/54.4] Uncertainty in HRVkm/sstat.errorfloatJ/ApJ/769/66/wdbinWhite dwarf physical parameters and binary orbital parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameWhite dwarf identifier (JHHMM-DDMM)meta.id;meta.maincharprimaryNvNumber of radial velocity measurementsmeta.numberintnullableRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainTeff[11560/21470] Effective temperatureKphys.temperature.effectiveinte_Teff[180/350] Teff uncertaintyKstat.error;phys.temperature.effectiveintlogg[5/7.8] Surface gravitylog(cm.s**-2)phys.gravityfloate_logg[0.04/0.08] logg uncertaintylog(cm.s**-2)stat.errorfloatMass[0.1/0.5] Mass of the white dwarfsolMassphys.massfloatgmag0[15.8/20.1] De-reddened g-band magnitude from SDSSmagphot.mag;em.opt.Bfloate_gmag0[0.01/0.04] gmag0 uncertaintymagstat.error;phot.magfloatgMag[6.7/11.2] Absolute g-band magnitudemagphys.magAbsfloatDist[0.1/2.6] Estimated heliocentric distancekpcpos.distancefloatSimbadSimbad column added by the CDSmeta.ref.urlcharPer[0.04/1.1] Orbital perioddtime.perioddoublee_PerPer uncertaintydstat.errordoubleK[80.8/432.6] radial velocity semi-amplitudekm/sspect.dopplerVelocfloate_K[2.3/7.5] K uncertaintykm/sstat.errorfloatgamma[-158/78] Systemic velocity {gamma}km/sphys.veloc;pos.heliocentricfloate_gamma[1.2/4.8] gamma uncertaintykm/sstat.errorfloatHJDTime of spectroscopic conjunction; HJD-2450000dtime.epochdoublee_HJDHJD uncertaintydstat.error;time.epochdoublel_M2[>=] Limit flag on M2meta.code.errorM2[0.1/1.2] Minimum secondary mass (assuming i=90{deg})solMassphys.mass;stat.minfloatl_q[<=] Limit flag on qmeta.code.errorq[0.1/0.9] Maximum mass ratiophys.mass;stat.maxfloatl_tau[<=] Limit flag on taumeta.code.errortau[0.1/620] {tau}_merge_, maximum merging time from gravitational waveGyrtime.epoch;stat.maxfloatVPVelocity Plotmeta.ref.urlchar