J/A+A/703/A175ivo://CDS.VizieR/J/A+A/703/A175CDSHolgado G.Simon-Diaz S.Herrero A.2025-11-13T08:17:45Z2025-11-13T09:16:44ZCDS support team

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

cds-question@unistra.frearly-type-starsspectroscopyoptical-observationcatalogsmilky-way-galaxyModern spectroscopic surveys combined with Gaia distances are enabling reliable estimates of fundamental parameters for hundreds of Galactic O-type stars and the full range of spectral types and luminosity classes. Here we provide updated, statistically robust empirical calibrations of the fundamental parameters of Galactic O-type stars, as well as of their absolute visual magnitudes (Mv) and bolometric corrections (BC), based on high-quality observational data. We perform a homogeneous analysis of a sample of 358 Galactic O-type stars, combining high-resolution spectroscopy and Gaia distances. A subset of 234 stars meeting strict quality criteria involving parallax, extinction, and multi-band photometry was used to derive empirical calibrations of fundamental parameters. For those same stars, calibrated parameters were estimated from their measured Mv using the derived relations, allowing us to assess the internal consistency and predictive power of the calibrations. We present updated spectral-type-based calibrations of fundamental parameters for luminosity classes V, III, and I. Compared to previous works, we find systematic shifts, particularly in effective temperature for dwarfs and in Mv across all classes, which propagate into derived quantities. Applying the Mv calibrations to the full sample yields consistent estimates of radius and luminosity, while spectroscopic mass (Msp) shows significant scatter. We also evaluate the FW3414 parameter (from the Hbeta line) as a calibrator for Mv, useful in large surveys lacking reliable spectral classification. Excluding SB1 systems has a noticeable impact only on the Msp calibration for LC V. These updated empirical calibrations offer a robust reference for Galactic O-type stars and will support studies of massive star populations in both Galactic and extragalactic contexts, particularly in the era of large spectroscopic surveys.2025A&A...703A.175Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/703/A175CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/562/A135 : Northern Galactic OB stars vsini (Simon-Diaz+, 2014)J/A+A/597/A22 : Massive O- and B-type stars velocities (Simon-Diaz+, 2017)J/A+A/613/A65 : Spectroscopic parameters of O-type stars (Holgado+, 2018)J/A+A/613/A9 : Extinction towards Galactic O stars (Maiz Apellaniz+, 2018)J/A+A/638/A157 : O-type stars near ZAMS elusive detection (Holgado+, 2020)J/A+A/665/A150 : Rot. properties of Galactic O-type stars (Holgado+ 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/703/A175https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/703/A175http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/703/A175https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/703/A175https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/703/A175http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/703/A175GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/703/A175/tabled1 (Galactic O-type stars calibrator with spectroscopic and fundamental parameters available)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/703/A175/tabled1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/703/A175/tabled1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/703/A175/tabled1?GETtext/xml+votable180.050000true341.960790858.08676610.0055555555555555565/3661 6/1287 1297 1303 2899 3037 3051 3214 3231 3245 3247 3249 3256-3257 3263 3272 3307-3308 3315 3585 3600 3622 3649 3653 3724 3755 12943 14263 14283 14295 14311 14326 14353 14358-14359 14456 14607 14623 14625 14630 14632-14633 14636 14643 14654-14655 14658 14689-14690 14712 14737 14740-14741 14743 14745 14793 14795 15476 15478 15656 15663 15670 15682-15683 21635 22033 22088 22211 22216 22240 22243 22249 23647 23774 23962 23984 23996 24179 28719 28865 28891 28895 28915 29091 29095 29098 29101 29115 29118 29158 29162 29461 29463 29467 29512-29513 29515 29517 29530 29600 30216 31748 37245 37333-37334 37339 37750 37833 37870 37897 37899-37900 37907 37923 37926 37930 37932 37934 37938 37948 38016 38020 38022 38024 38026 38074 39238 39248 39264 39374 39873 39876 39931 39971 41630 41652 41668 41675 41685 41702 41769 41787 41813 42206 42226 42228 42283 42303 42335 42383 42390 42394 42398 42405 42417 42456 42458 42471 42764 42768 43026 43030 43034 430411.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/703/A175?format=asciiOpticaldefaultJ/A+A/703/A175/tabled1Galactic O-type stars calibrator with spectroscopic and fundamental parameters availablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar namemeta.id;meta.maincharSpTypeSpectral type (1)src.spTypecharSBStatusMulti-epoch notesmeta.notecharNspNumber of spectra availablemeta.numberintvsiniprojected rotational velocitykm/sphys.veloc.rotatintTeffEffective temperaturekKphys.temperature.effectivefloate_TeffEffective temperature uncertaintykKstat.error;phys.temperature.effectivefloatloggcGravity corrected from rotational effectslog(cm.s**-2)phys.gravityfloate_loggcGravity corrected from rot. uncertaintylog(cm.s**-2)stat.errorfloatGmagcorrGaia G magnitude (following Maiz Apellaniz et al., 2018A&A...619A.180M, Cat. J/A+A/619/A180)magphot.mag;em.opt.RfloatAvvisual extinction in V bandmagphys.absorptionfloate_Avvisual extinction in V band uncertaintymagstat.errorfloatdALSdistance from the ALS catalog (1)pcpos.distanceinte_dALSdistance from the ALS catalog uncertaintypcstat.errorintVMAGAbsolute V magnitudemagphys.magAbsfloate_VMAGAbsolute V magnitude uncertaintymagstat.errorfloatRStellar radiussolRadphys.size.radiusfloate_RStellar radius uncertaintysolRadstat.errorfloatlogLlogarithm of stellar luminositylog(solLum)phys.luminosityfloatSimbadSimbad column added by the CDSmeta.ref.urlchare_logLlogarithm of stellar luminosity uncertaintylog(solLum)stat.errorfloatMspcStellar mass, corrected from rotational effectssolMassphys.massfloate_MspcStellar mass uncertaintysolMassstat.errorfloatBCvBolometric correction derived from luminositymagphot.mag.bcfloate_BCvBolometric correction uncertaintymagstat.errorfloatFW3414EW of Hbeta at 3/4 - EW at 1/4spect.linefloat_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.main