J/A+A/453/309ivo://CDS.VizieR/J/A+A/453/309doi:10.26093/cds/vizier.34530309CDSNardetto N.Mourard D.Kervella P.Mathias P.Merand A.Bersier D.2017-11-06T12:24:00Z2007-11-07T15:36:06ZCDS support team

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

cds-question@unistra.frvariable-starsspectroscopyradial-velocityThe ratio of pulsation to radial velocity (the projection factor) is currently limiting the accuracy of the Baade-Wesselink method, and in particular of its interferometric version recently applied to several nearby Cepheids. This work aims at establishing a link between the line asymmetry evolution over the Cepheids' pulsation cycles and their projection factor, with the final objective to improve the accuracy of the Baade-Wesselink method for distance determinations. We present HARPS high spectral resolution observations (R=120000) of nine galactic Cepheids: R Tra, S Cru, Y Sgr, beta Dor, zeta Gem, Y Oph, RZ Vel, l Car and RS Pup, having a good period sampling (P=3.39d to P=41.52d). We fit spectral line profiles by an asymmetric bi-Gaussian to derive radial velocity, Full-Width at Half-Maximum in the line (FWHM) and line asymmetry for all stars.2006A&A...453..309Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/453/309CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/453/309https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/453/309http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/453/309https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/453/309https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/453/309http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/453/309GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/453/309/table1 (Observed sample of Cepheids (sorted by increasing period))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/453/309/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/453/309/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/453/309/table1?GETtext/xml+votable180.050000true229.9404764-66.49603470.0055555555555555566/23922 29104 29665 33804 37303 39244 39410 41385 43060https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/453/309?format=asciiOpticaldefaultJ/A+A/453/309/table1Observed sample of Cepheids (sorted by increasing period)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharprimaryHDHD numbermeta.idintPerPulsation period (1)dtime.perioddoubleT0Reference Julian date (1)dmeta.ref;time.epochdoubleNspNumber of spectrameta.numberintNcNumber of cyclesmeta.numberintVmagVisible magnitude from Berdnikov et al. (2000, Cat. <J/A+AS/143/211>magphot.mag;em.opt.VfloatSimbadSimbad column added by the CDSchar_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/A+A/453/309/table345HARPS observations resultsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharJDAverage Julian data of observationdtime.epoch;obsdoublePhaseAverage pulsation phase of observation. For ephemeris, see the Papertime.phasefloatCyclePulsating cycle of the star corresponding to observationobsintNSpecNumber of spectra associated to observation (1)meta.numberintRVgGaussian fit radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_RVgrms uncertainty on RVgkm/sstat.errorfloatRVmMinimum radial velocity (2)km/sspect.dopplerVeloc;stat.minfloate_RVmrms uncertainty on RVmkm/sstat.errorfloatRVcRadial velocity corresponding to the first moment of the spectral linekm/sspect.dopplerVeloc;spect.linefloate_RVcrms uncertainty on RVckm/sstat.errorfloatFWHMFull-Width at Half Maximum (2)0.1nmspect.line.widthfloate_FWHMrms uncertainty to FWHM0.1nmstat.error;phys.angSizefloatDLine depth. Uncertainties are of about 10^-4^ (2)phot.flux.density;arith.ratiofloatAAsymmetry (2)%stat.fit.paramfloate_AUncertainty corresponding to the asymmetry%stat.errorfloatSNRObservational spectral line signal to noise ratiostat.snrintChi2Reduced Chi2 factor corresponding to the bi-Gaussian fitstat.fit.chi2;stat.fit.param;meta.modelledfloat