J/A+A/341/818ivo://CDS.VizieR/J/A+A/341/818doi:10.26093/cds/vizier.33410818CDSKienzle F.Moskalik P.Bersier DPont F.1999-01-24T15:29:23Z1999-01-24T16:28:13ZCDS support team

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

cds-question@unistra.frvariable-starsradial-velocityThe light curves of the first overtone Pop. I Cepheids (s-Cepheids) show a discontinuity in their {phi}_21_ vs. P diagram, near P=3.2day. This feature, commonly attributed to the 2:1 resonance between the first and the fourth overtones ({omega}_4_~2{omega}_1_), is not reproduced by the hydrodynamical models. With the goal of reexamining the resonance hypothesis, we have obtained new CORAVEL radial velocity curves for 14 overtone Cepheids. Together with 10 objects of Krzyt et al. (1999, in prep.), the combined sample covers the whole range of overtone Cepheid periods. The velocity Fourier parameters display a strong characteristic resonant behavior. In striking contrast to photometric ones, they vary smoothly with the pulsation period and show no jump at 3.2day. The existing radiative hydrodynamical models match the velocity parameters very well. The center of the {omega}_4_=2{omega}_1_ resonance is estimated to occur at Pr=4.58+/-0.04day, i.e. at a period considerably longer than previously assumed (3.2day). We identify two new members of the s-Cepheid group: MY Pup and V440 Per.1999A&A...341..818Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/341/818CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/108/9 : Cepheids fundamental parameters I. (Bersier+, 1994)J/A+AS/108/25 : Cepeheids fundamental parameters II. (Bersier+, 1994)J/A+A/305/551 : Chemical composition of the s-Cepheids (Andrievsky+, 1996)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/341/818https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/341/818http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/341/818https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/341/818https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/341/818http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/341/818GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/341/818/table1 (Fourier parameters of cepheids)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/341/818/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/341/818/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/341/818/table1?GETtext/xml+votable180.050000true104.7083339.6250.005555555555555556https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/341/818?format=asciiOpticaldefaultJ/A+A/341/818/table1Fourier parameters of cepheidsNNumber of harmonics fittedmeta.idintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSTARStar name according to GCVSmeta.id;meta.maincharprimaryPeriodPerioddtime.perioddoublee_PeriodOne sigma error Perioddstat.errordoubleMNumber of data pointsmeta.numberintsigmaRMS of the residualskm/sstat.stdevfloatA0Gamma velocitykm/sstat.Fourier.amplitudefloate_A0One sigma error gamma velocitykm/sstat.errorfloatA1Amplitude A1km/sstat.fit.paramfloate_A1One sigma error amplitude A1km/sstat.errorfloatR21Amplitude ratio A2/A1phot.mag;arith.ratiofloate_R21One sigma error amplitude ratio R21stat.errorfloatf21Phase shift phi2-2*phi1stat.fit.paramfloate_f21One sigma error phase shift f21stat.errorfloatR31? Amplitude ratio A3/A1phot.mag;arith.ratiofloatnullablee_R31? One sigma error amplitude ratio R31stat.errorfloatnullablef31? Phase shift phi3-3*phi1stat.fit.paramfloatnullablee_f31? One sigma error phase shift f31stat.errorfloatnullableR41? Amplitude ratio A4/A1phot.mag;arith.ratiofloatnullablee_R41? One sigma error amplitude ratio R41stat.errorfloatnullablef41? Phase shift phi4-4*phi1stat.fit.paramfloatnullablee_f41? One sigma error phase shift f41stat.errorfloatnullableR51? Amplitude ratio A5/A1phot.mag;arith.ratiofloatnullablee_R51? One sigma error amplitude ratio R51stat.errorfloatnullablef51? Phase shift phi5-5*phi1stat.fit.paramfloatnullablee_f51? One sigma error phase shift f51stat.errorfloatnullableRAJ2000Right Ascension J2000 (hours) (1)pos.eq.ra;meta.mainDEJ2000Declination J2000 (degrees) (1)pos.eq.dec;meta.mainJ/A+A/341/818/dataIndividual CORAVEL velocitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSTARStar name according to GCVSmeta.id;meta.maincharprimaryHJDHeliocentric julian daydtime.epochdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricfloate_RVOne sigma errorkm/sstat.errorfloat