J/MNRAS/483/5026ivo://CDS.VizieR/J/MNRAS/483/5026doi:10.26093/cds/vizier.74835026CDSLeao I.C.Pasquini L.Ludwig H.-G.de Medeiros J.R.2024-08-19T20:16:07Z2022-08-18T12:25:25ZCDS support team

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

cds-question@unistra.fropen-star-clusterslate-type-starsradial-velocityastrometryvisible-astronomyWe study the accuracy of spectroscopic radial velocities (RVs) by comparing spectroscopic and astrometric RVs for stars of the Hyades open cluster. We obtained High-Accuracy Radial velocity Planet Searcher (HARPS) spectra for a large sample of Hyades stars and combined them with accurate astrometric RVs based on Hipparcos and Gaia data. After cleaning the sample from binaries, RV variables, and outliers, 71 stars remained. The distribution of the observed RV difference (between spectroscopic and astrometric) is skewed and depends on the star right ascension. This is consistent with the Hyades cluster rotating at 42.3m/s/pc. The two Hyades giants in the sample show, as predicted by gravitational redshift (GR), a spectroscopic RV that is blue-shifted with respect to the dwarfs, and the empirical GR slope is of 626+/-131m/s, in agreement with the theoretical prediction. The difference between spectroscopic and astrometric RVs is close to zero when considering the Gaia-based RVs corrected for cluster rotation. The mean difference is of -33m/s and the median is of -16m/s, with a standard deviation of 347m/s being close to the expected cluster velocity dispersion. We also determine a new value of the cluster centroid spectroscopic RV: 39.36+/-0.26km/s. We finally discuss other phenomena that can influence the RV difference, such as cluster expansion, stellar rotation, stellar activity, general relativity, and Galactic potential. Clusters within the reach of current telescopes are expected to show differences of several hundreds m/s, depending on their position in the Galaxy.2019MNRAS.483.5026Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/483/5026CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/483/5026https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/483/5026http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/483/5026https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/483/5026https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/483/5026http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/483/5026GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/483/5026/table1 (Selected objects in the Hyades cluster)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/483/5026/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/483/5026/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/483/5026/table1?GETtext/xml+votable180.050000true43.817856117.89171080.005555555555555556Cone search capability for table J/MNRAS/483/5026/table2 (Gravitational and convective shifts)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/483/5026/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/483/5026/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/483/5026/table2?GETtext/xml+votable180.050000true53.209423.6920.0055555555555555565/5881 6/60 78 251 272 309 320 322-323 325 333-334 336-337 340-342 348-350 353 357 373 375 456 472 483 770 835 840 917 1024-1025 1032-1033 1042 1058 1060 1064 1075 1096 1167 17904 23017 23276 23286 23313 23339 23344 23383 23392 23410 23450 23454 23463 23478-23479 23489-23490 23493 23496-23497 23499 23501-23504 23511 23515 23518 23522-23523 23529 23533-23535 23537-23539 23544-23545 23547-23548 23550 23561 24068 24099 24104 24110 24137 24192 24194-24195 24203 24206-24207 24209 24218 24232 24251https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/483/5026?format=asciiOpticaldefaultJ/MNRAS/483/5026/table1Selected objects in the Hyades clusterrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmoreindicates cross-correlation results (table 2) and/or additional astrometric data (table B1)meta.ref.urlcharID[1/131] Internal object identifiermeta.idintprimaryNameHiparcos number (HIP NNNNN)meta.id;meta.maincharSpTypeSpectral type from the Hipparcos cataloguesrc.spTypecharVmagVisual magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.Vfloate_B-VError on B-Vmagstat.error;phot.color;em.opt.BfloatRVP98Spectroscopic radial velocity from Perryman et al. 1998A&A...331...81P, Cat. J/A+A/331/81 (P98)km/sphys.veloc;pos.heliocentricfloate_RVP98Error on RVP98km/sstat.errorfloatRVM02Astrometric radial velocity from Madsen et al. 2002A&A...381..446M, Cat. J/A+A/381/446 (M02)km/sphys.veloc;pos.heliocentricfloate_RVM02Error on RVM02km/sstat.errorfloatRVG17Astrometric radial velocity computed in this work from Gaia DR1 data (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337)km/sphys.veloc;pos.heliocentricfloate_RVG17Error on RVG17km/sstat.errorfloatRVHarpsHARPS radial velocity (1)km/sphys.veloc;pos.heliocentricdoublee_RVHarpsError on RVHarpskm/sstat.errorfloatFWHMFull width at half-maximum of the HARPS CCFkm/sspect.line.widthfloatS/NSignal to noise ratio at 490umstat.snrintq_RVHarpsQuality flag on HARPS data (2)meta.code.qualcharSimbadSimbad 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/MNRAS/483/5026/table2Gravitational and convective shiftse_B-VError on B-Vmagstat.error;phot.color;em.opt.BfloatIDInternal object identifiermeta.idintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameHiparcos number (HIP NNNNN)meta.id;meta.maincharRAJ2000Right ascension (J2000) (1)degpos.eq.ra;meta.mainDEJ2000Declination (J2000) (1)degpos.eq.dec;meta.mainM/RStellar mass to radius ratioSunphys.massfloate_M/RError on M/RSunstat.errorfloatGRGravitational redshiftm/ssrc.redshift;pos.heliocentricintCEstimated convective shiftm/sphys.veloc;arith.diffintGRCGravitational plus convective shiftsm/sphys.veloc;arith.diffintDRVM02Radial velocity difference between HARPS (without zero-point correction) and Madsen et al. (2002A&A...381..446M, Cat. J/A+A/381/446) measurementsm/sphys.veloc;arith.diffintDRVM02GRDRVM02 corrected for gravitational redshiftm/sphys.veloc;arith.diffintDRVM02GRCDRVM02 corrected for gravitational plus convective shiftsm/sphys.veloc;arith.diffintDRVG17Radial velocity difference between HARPS (without zero-point correction) and Gaia DR1 (Gaia collaboration, 2017A&A...601A..19G, Cat. I/337) measurementsm/sphys.veloc;arith.diffintDRVG17GRDRVG17 corrected for gravitational redshiftm/sphys.veloc;arith.diffintDRVG17GRCDRVG17 corrected for gravitational plus convective shiftsm/sphys.veloc;arith.diffintSpTypeSpectral type from the Hipparcos cataloguesrc.spTypecharVmagVisual magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.VfloatRVP98Spectroscopic radial velocity from Perryman et al. 1998A&A...331...81P, Cat. J/A+A/331/81 (P98)km/sphys.veloc;pos.heliocentricfloate_RVP98Error on RVP98km/sstat.errorfloatRVM02Astrometric radial velocity from Madsen et al. 2002A&A...381..446M, Cat. J/A+A/381/446 (M02)km/sphys.veloc;pos.heliocentricfloate_RVM02Error on RVM02km/sstat.errorfloatRVG17Astrometric radial velocity computed in this work from Gaia DR1 data (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337)km/sphys.veloc;pos.heliocentricfloate_RVG17Error on RVG17km/sstat.errorfloatRVHarpsHARPS radial velocity (2)km/sphys.veloc;pos.heliocentricfloate_RVHarpsError on RVHarpskm/sstat.errorfloatFWHMFull width at half-maximum of the HARPS CCFkm/sspect.line.widthfloatS/NSignal to noise ratio at 490umstat.snrintq_RVHarpsQuality flag on HARPS data (3)meta.code.qualcharr-rc? Distance from the cluster centerpcpos.distancefloatnullablee_r-rc? Error on r-rcpcstat.errorfloatnullableValpha? Tangential component in the {alpha} direction for the astrometric vectors computed from Gaia DR1 (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337) (4)km/sphys.velocfloatnullablee_Valpha? Error on Valphakm/sstat.errorfloatnullableVdelta? Tangential component in the {delta} direction for the astrometric vectors computed from Gaia DR1 (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337) (4)km/sphys.velocfloatnullablee_Vdelta? Error on Vdeltakm/sstat.errorfloatnullableCREstimated cluster rotation effectm/sphys.veloc;arith.diffintRVHGRCRVHarps corrected for gravitational plus convective shiftsm/sphys.veloc;pos.heliocentricfloatRVG17CRRVG17 corrected for cluster rotation effectm/sphys.veloc;pos.heliocentricfloatDRVG17GRCCRDRVG17 corrected for gravitational plus convective shifts and cluster rotation effectm/sphys.veloc;arith.diffintJ/MNRAS/483/5026/tablea1Cross-correlation resultsFWHM7.0FWHM of the cross-correlation peak for {xi}=7.0km/s (1)km/sspect.line.widthfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpecIDSynthetic spectra identifiermeta.id;meta.maincharTeffEffective temperatureKphys.temperature.effectiveintloggSurface gravitylog(cm.s**-2)phys.gravityfloatFWHM0.0FWHM of the cross-correlation peak for {xi}=0.0km/s (1)km/sspect.line.widthfloatFWHM1.0FWHM of the cross-correlation peak for {xi}=1.0km/s (1)km/sspect.line.widthfloatFWHM2.0FWHM of the cross-correlation peak for {xi}=2.0km/s (1)km/sspect.line.widthfloatFWHM2.44FWHM of the cross-correlation peak for {xi}=2.44km/s (1)km/sspect.line.widthfloatFWHM3.0FWHM of the cross-correlation peak for {xi}=3.0km/s (1)km/sspect.line.widthfloatFWHM4.0FWHM of the cross-correlation peak for {xi}=4.0km/s (1)km/sspect.line.widthfloatFWHM5.0FWHM of the cross-correlation peak for {xi}=5.0km/s (1)km/sspect.line.widthfloatFWHM6.0FWHM of the cross-correlation peak for {xi}=6.0km/s (1)km/sspect.line.widthfloatFWHM8.0FWHM of the cross-correlation peak for {xi}=8.0km/s (1)km/sspect.line.widthfloatFWHM9.0FWHM of the cross-correlation peak for {xi}=9.0km/s (1)km/sspect.line.widthfloatFWHM10.0FWHM of the cross-correlation peak for {xi}=10.0km/s (1)km/sspect.line.widthfloatFWHM12.5FWHM of the cross-correlation peak for {xi}=12.5km/s (1)km/sspect.line.widthfloatFWHM15.0FWHM of the cross-correlation peak for {xi}=15.0km/s (1)km/sspect.line.widthfloatFWHM17.5FWHM of the cross-correlation peak for {xi}=17.5km/s (1)km/sspect.line.widthfloatFWHM20.0FWHM of the cross-correlation peak for {xi}=20.0km/s (1)km/sspect.line.widthfloatpos0.0Position of the cross-correlation peak for {xi}=0.0km/s (1)m/spos.eqintpos1.0Position of the cross-correlation peak for {xi}=1.0km/s (1)m/spos.eqintpos2.0Position of the cross-correlation peak for {xi}=2.0km/s (1)m/spos.eqintpos2.44Position of the cross-correlation peak for {xi}=2.44km/s (1)m/spos.eqintpos3.0Position of the cross-correlation peak for {xi}=3.0km/s (1)m/spos.eqintpos4.0Position of the cross-correlation peak for {xi}=4.0km/s (1)m/spos.eqintpos5.0Position of the cross-correlation peak for {xi}=5.0km/s (1)m/spos.eqintpos6.0Position of the cross-correlation peak for {xi}=6.0km/s (1)m/spos.eqintpos7.0Position of the cross-correlation peak for {xi}=7.0km/s (1)m/spos.eqintpos8.0Position of the cross-correlation peak for {xi}=8.0km/s (1)m/spos.eqintpos9.0Position of the cross-correlation peak for {xi}=9.0km/s (1)m/spos.eqintpos10.0Position of the cross-correlation peak for {xi}=10.0km/s (1)m/spos.eqintpos12.5Position of the cross-correlation peak for {xi}=12.5km/s (1)m/spos.eqintpos15.0Position of the cross-correlation peak for {xi}=15.0km/s (1)m/spos.eqintpos17.5Position of the cross-correlation peak for {xi}=17.5km/s (1)m/spos.eqintpos20.0Position of the cross-correlation peak for {xi}=20.0km/s (1)m/spos.eqintJ/MNRAS/483/5026/tableb1Additional astrometric dataIDInternal object identifiermeta.idintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameHiparcos number (HIP NNNNN)meta.id;meta.maincharr-rcDistance from the cluster centerpcpos.distancefloate_r-rcError on r-rcpcstat.errorfloatValphaTangential component in the {alpha} direction for the astrometric vectors computed from Gaia DR1 (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337) (1)km/sphys.velocfloate_ValphaError on Valphakm/sstat.errorfloatVdeltaTangential component in the {delta} direction for the astrometric vectors computed from Gaia DR1 (Gaia Collaboration 2017A&A...601A..19G, Cat. I/337) (1)km/sphys.velocfloate_VdeltaError on Vdeltakm/sstat.errorfloat