J/A+A/640/A36ivo://CDS.VizieR/J/A+A/640/A36doi:10.26093/cds/vizier.36400036CDSBowman D.M.Burssens S.Simon-diaz S.Edelmann P.V.F.Rogers T.M.,Horst L.Ropke F.K.Aerts C.2021-02-02T09:06:56Z2020-11-20T09:24:12ZCDS support team

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

cds-question@unistra.frob-starsasteroseismologyspectroscopyMassive stars are predicted to excite internal gravity waves (IGWs) by turbulent core convection and from turbulent pressure fluctuations in their near-surface layers. These IGWs are extremely efficient at transporting angular momentum and chemical species within stellar interiors, but they remain largely unconstrained observationally. We aim to characterise the photometric detection of IGWs across a large number of O and early-B stars in the Hertzsprung-Russell diagram, and explain the ubiquitous detection of stochastic variability in the photospheres of massive stars. We combined high-precision time-series photometry from the NASA Transiting Exoplanet Survey Satellite with high-resolution ground-based spectroscopy of 70 stars with spectral types O and B to probe the relationship between the photometric signatures of IGWs and parameters such as spectroscopic mass, luminosity, and macroturbulence. A relationship is found between the location of a star in the spectroscopic Hertzsprung-Russell diagram and the amplitudes and frequencies of stochastic photometric variability in the light curves of massive stars. Furthermore, the properties of the stochastic variability are statistically correlated with macroturbulent velocity broadening in the spectral lines of massive stars. The common ensemble morphology for the stochastic low-frequency variability detected in space photometry and its relationship to macroturbulence is strong evidence for IGWs in massive stars, since these types of waves are unique in providing the dominant tangential velocity field required to explain the observed spectroscopy.2020A&A...640A..36Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/640/A36CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)J/A+A/639/A81 : Variability of OB stars (Burssens+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/640/A36https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/640/A36http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/640/A36https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/640/A36https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/640/A36http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/640/A36GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/640/A36/tablea1 (Parameters of OB stars studied in this work)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/640/A36/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/640/A36/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/640/A36/tablea1?GETtext/xml+votable180.050000true166.8867369-59.96352890.0055555555555555566/16490 20613 20759 20782 20834 20847 20860 20862 20915 21233 21401 21436 21438-21439 21635 21638 21655-21656 21729 22173 22211 22223 22240 22249 22269 22730 22854 22862 22893 23007 23442 23637 23701 23717 23764 23769 23774 24132 37861 37870 37926 37930-37931 38026 39853 39907 40617 41686 41750 42228 42303 42383 42394 42416 42456 42458 42470-42471 43034 43062https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/640/A36?format=asciidefaultJ/A+A/640/A36/tablea1Parameters of OB stars studied in this workrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCat[1/9] Category (G1)meta.codeintNameCommon namemeta.id;meta.maincharTICTIC numbermeta.idlongSpTypeSpectral typesrc.spTypecharlogTeffEffective temperature (typical uncertainty 0.03dex)log(K)phys.temperature.effectivefloatlogLsSpectroscopic luminosity (where Ls=Teff^4^/g) (typical uncertainty 0.15dex)log(Sun)stat.fit.paramfloatvsiniProjected surface rotational velocity (1)km/sphys.veloc.rotatintvmacro? Macroturbulent broadening (1)km/sspect.line.broadintnullableSimbadSimbad 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/A+A/640/A36/tablea2Optimised parameters for the morphology of low-frequency variability (cf. Eq. (2)) using a Bayesian MCMC fitting methodCat[1/9] Category (G1)meta.codeintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameCommon namemeta.id;meta.maincharTICTIC numbermeta.idlongalpha0Amplitude at a frequency of zeroumagsrc.var.amplitudedoublee_alpha0rms uncertainty on alpha0umagstat.errorfloatnucharCharacteristic frequencyd**-1em.freq;src.vardoublee_nucharrms uncertainty on nuchard**-1stat.errordoublegammalogarithmic amplitude gradientstat.fit.paramdoublee_gammarms uncertainty on gammastat.errordoubleCwFrequency-independent noise termumagstat.fit.paramfloate_Cwrms uncertainty on Cwumagstat.errorfloat