J/ApJS/275/2ivo://CDS.VizieR/J/ApJS/275/2doi:10.26093/cds/vizier/bb-8k-2CDSShen D.-X.Zhu C.-H.Lu G.-L.Lu X.-Z.He X.-L.2026-08-03T07:25:39Z2025-09-22T15:21:15ZCDS support team

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

cds-question@unistra.fro-starsvisible-astronomyspectroscopyphotometrysurveysstellar-spectral-typesstellar-massesstellar-radiiIn order to explore how the ubiquitous stochastic low-frequency (SLF) variability of O-type stars is related to various stellar characteristics, we compiled a sample of 150 O-type stars observed via ground-based spectroscopic surveys, alongside photometric data obtained from the Transiting Exoplanet Survey Satellite (TESS). We analyzed 298 light curves obtained from TESS Sectors 1-65 for the stars in our sample. Leveraging the spectroscopic parameters, we used Bonnsai to determine masses, radii, fractional main-sequence ages, and mass-loss rates for stars of our sample. Subsequently, we identified possible correlations between the fitted parameters of SLF variability and stellar properties. Our analysis unveiled four significant correlations between the amplitude and stellar parameters, including mass, radius, fractional main-sequence ages, and mass-loss rate. For stars with >~30M_{sun}_, we observed a decrease in characteristic frequency and steepness with increasing radius. Finally, we compared various physical processes that may account for the SLF variability with our results. The observed SLF variability may arise from the combined effects of the iron convection zone (FeCZ) and internal gravity waves (IGWs), with IGWs potentially more dominant in the early stages of stellar evolution, and the contribution of FeCZ becoming more significant as stars evolve. Meanwhile, our results indicate that the SLF variability of O-type stars bears certain signatures of the line-driven wind instability and granulation.2024ApJS..275....2Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/275/2CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/274 : Galactic O-Star Spectroscopic Survey (GOSSS) (Sota+, 2014)IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)J/other/IBVS/5480 : Elements for 80 eclipsing binaries (Otero, 2003)J/other/IBVS/5495 : Elements for 80 eclipsing binaries. II. (Otero+, 2004)J/A+A/479/541 : VLT-FLAMES survey of massive stars (Hunter+, 2008)J/A+A/533/A4 : CoRoT photometry of three O-type stars (Blomme+, 2011)J/A+A/530/A115 : Rot. massive MS stars evolutionary models (Brott+, 2011)J/AJ/141/17 : 5-yr spectroscopy & phot. of Deneb (Richardson+, 2011)J/other/Sci/337.444 : RV curves of Galactic massive O stars (Sana+, 2012)J/A+A/550/A109 : VLT-FLAMES Tarantula Survey: vsini (Dufton+ 2013)J/A+A/560/A29 : O-stars in Tarantula Survey (Ramirez-Agudelo+ 2013)J/ApJS/215/15 : SMaSH+: obs. and companion detection (Sana+, 2014)J/A+A/562/A135 : Northern Galactic OB stars vsini (Simon-Diaz+, 2014)J/AJ/152/31 : Spectral classif. of O Vz stars from GOSSS (Arias+, 2016)J/ApJS/224/4 : GOSSS III. O-type systems (Maiz Apellaniz+, 2016)J/A+A/597/A22 : Massive O- & B-type stars velocities (Simon-Diaz+, 2017)J/A+A/619/A97 : CoRoT transit catalogue (Deleuil+, 2018)J/A+A/613/A65 : Spectroscopic parameters of O-type stars (Holgado+, 2018)J/AJ/156/83 : Effect of stellar companions on pl. (Ziegler+, 2018)J/other/NatAs/3.760 : Supergiants low-frequency gravity waves (Bowman+, 2019)J/A+A/640/A36 : OB stars TESS phot. & high-resolution sp. (Bowman+, 2020)J/A+A/639/A81 : Variability of OB stars (Burssens+, 2020)J/A+A/638/A157 : Massive O-type stars near ZAMS detection (Holgado+, 2020)J/AJ/161/24 : TRICERATOPS predictions for 384 TOIs (Giacalone+, 2021)J/A+A/665/A150 : Rotational data of Galactic O-type stars (Holgado+ 2022)J/A+A/674/A212 : Sp. sample of Galactic O9-B9 SGs (de Burgos+, 2023)J/A+A/678/A24 : Rotation periods of 67163 Kepler stars (Reinhold+, 2023)J/A+A/676/A28 : Six ULA Cepheids light curves (Tarczay-Nehez+, 2023)J/A+A/676/A81 : Be stars in the exofield of CoRoT. III. (Zorec+, 2023)http://heasarc.gsfc.nasa.gov/docs/tess/ : NASA TESS Science Support Centerhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/275/2https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/275/2http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/275/2https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/275/2https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/275/2http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/275/2GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/275/2/table1 (Stellar parameters of stars in our sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/275/2/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/275/2/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/275/2/table1?GETtext/xml+votable180.050000true309.075859437.41744860.0055555555555555565/3661 6/1287 1293 1303 1332 1355 1558 1790 1946 2409 3037 3051 3054 3066 3214 3231 3245 3247 3249 3256 3261 3263 3272 3301 3307 3315 3331 3600 3622 3653 3724 5506 6891 13255 13557 13999 14008 14179 14240 14253 14283 14295 14311 14353 14359 14623 14630-14633 14643 14654 14658 14690 14692-14693 14712 14740-14741 14743 14745 14793 14824 15476 15631 15656 15663 15670 15672 15682-15683 15745 20613 21432 21439 21638 21655-21656 22211 22216 22240 22243 22249 22517 23717 23780 23962 23982 24179 24555 37245 37333-37335 37343 37861 37863 37870 37900 37907 37915 37926 37930 37938 38016 38022 38024 38026 39264 39374 39386 39804 39971 41702 41750 42228 42236 42303 42394 42456 42458https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/275/2?format=asciiOpticaldefaultJ/ApJS/275/2/table1Stellar parameters of stars in our samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Name[1/2] Spectral observation flag (1)meta.codeintNameStar Namemeta.id;meta.mainprimarym_Name[A] Star name componentmeta.code.multipcharSpTSpectral typesrc.spTypecharLumLuminosity Classsrc.class.luminositycharSimbadNameSimbad column added by the CDSmeta.idcharnullableMass[16/82] Stellar masssolMassphys.massfloatlogLs[3.4/4.27] Log, spectroscopic luminositylog(solLum)phys.luminosityfloate_logLs[0.03/0.4] Uncertainty in logLslog(solLum)stat.error;phys.luminosityfloatTeff[27.7/49.1] Effective temperaturekKphys.temperature.effectivefloate_Teff[0.5/2.2] Uncertainty in TeffkKstat.error;phys.temperature.effectivefloatlogg[2.9/4.13] Log, surface gravitylog(cm.s**-2)phys.gravityfloate_logg[0.03/0.3] Uncertainty in logglog(cm.s**-2)stat.error;phys.gravityfloatE_Mass[0/7.4] Upper Uncertainty in MasssolMassstat.error;stat.max;phys.massfloate_Mass[0.4/15] Lower Uncertainty in MasssolMassstat.error;stat.min;phys.massfloatRad[6.17/47.5] Stellar RadiussolRadphys.size.radiusfloatE_Rad[0/1] Upper Uncertainty in RadsolRadstat.error;stat.max;phys.size.radiusfloate_Rad[0.27/6] Lower Uncertainty in RadsolRadstat.error;stat.min;phys.size.radiusfloattau[0.1/0.86] Fractional main sequence agetime.age;arith.ratiofloatE_tau[0.01/0.2] Upper Uncertainty in taustat.error;stat.min;time.agefloate_tau[0.01/0.3] Lower Uncertainty in taustat.error;stat.min;time.agefloatlogMdot[-7.9/-5] Mass-loss ratesolMass.yr**-1phys.mass.lossfloatE_logMdot[0.07/0.5] Upper Uncertainty in logMdotsolMass.yr**-1stat.error;stat.max;phys.mass.lossfloate_logMdot[0.05/0.4] Lower Uncertainty in logMdotsolMass.yr**-1stat.error;stat.min;phys.mass.lossfloatvmacro[7/440]? Macroturbulent velocitykm.s**-1phys.velocfloatnullablevsini[8/140]? Projected rotational velocitykm.s**-1phys.veloc.rotatfloatnullableIACOBDisplay data from Simon-Diaz+ 2014, J/A+A/562/A135 and Holgado+2020, J/A+A/638/A157 within 3"meta.ref.urlintnullableGOSSSDisplay data from GOSSS (III/274) within 3"meta.ref.urlintnullableNvarNumber of SLF variability results for this star (link to Table 2)meta.numberintnullable_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/ApJS/275/2/table2Results of stochastic low-frequency (SLF) variability for stars of our sampleNameStar Name as in Table 1meta.id;meta.mainnu-char[0.1/15.7] Characteristic frequency, {nu}_{char}_d**-1em.freq;src.varfloatE_nu-char[0.02/1.7] Upper Uncertainty in nu-chard**-1stat.error;stat.max;em.freqfloate_nu-char[0.02/1.7] Lower Uncertainty in nu-chard**-1stat.error;stat.min;em.freqfloatgamma[0.6/3] Logarithmic amplitude gradientarith.grad;src.var.amplitudefloatE_gamma[0.01/0.2] Upper Uncertainty in gammastat.error;stat.max;arith.gradfloate_gamma[0.01/0.2] Lower Uncertainty in gammastat.error;stat.min;arith.gradfloatCw[0.69/33] White noise termumaginstr.det.noisefloatE_Cw[0/0.3] Upper Uncertainty in Cwumagstat.error;stat.max;instr.det.noisefloate_Cw[0/0.3] Lower Uncertainty in Cwumagstat.error;stat.min;instr.det.noisefloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintm_Name[AabB ] Star name componentmeta.code.multipcharONameOther name (column added by CDS)meta.idcharSec[5/65] TESS sectormeta.id;obsintalpha0[36.7/19698] Scaling factor {alpha}_0_, amplitude at zero frequencyumagarith.factor;src.var.amplitudedoubleE_alpha0[2/5492] Upper Uncertainty in alpha0umagstat.error;stat.max;src.var.amplitudefloate_alpha0[1.9/3905] Lower Uncertainty in alpha0umagstat.error;stat.min;src.var.amplitudefloat