J/A+A/699/A82ivo://CDS.VizieR/J/A+A/699/A82doi:10.26093/cds/vizier/bc-nv/licCDSLabadie-Bartz J.Carciofi A.C.Rubio A.C.Baade D.Siverd R.Arcos C.,Figueiredo A.L.Naze Y.Neiner C.Rivinius T.Richardson N.D.Nova S.,Pinho M.L.Bhattacharyya S.Leadbeater R.Guarro Flo J.Lecocq V.,Piehler G.Kozok J.Sollecchia U.Bryssinck E.Buil C.Martin J.,Desnoux V.Heathcote B.Cacella P.Bertrand G.Broussat J.J.,Ventura A.Diz R.Blais A.Somogyi P.Thizy O.Garde O.Charbonnel S.,Le Du P.Mulato L.Petit T.2026-08-03T06:56:03Z2025-12-01T14:59:54ZCDS support team

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

cds-question@unistra.frbe-starsspectroscopyphotometrystellar-mass-lossClassical Be stars are well known to eject mass to build up a disk, but the details governing the initial distribution and subsequent evolution of this matter into a disk are in general poorly constrained through observations. By combining high-cadence time-series spectroscopy with contemporaneous space photometry from the Transiting Exoplanet Survey Satellite (TESS), we have sampled about 30 mass ejection events in 13 Be stars. Our goal is to constrain the geometrical and kinematic properties of the ejecta as early as possible, facilitating the investigation into the material's initial conditions and evolution, and understanding its interactions with preexisting material. The photometric variability is analyzed together with measurements of the at-times rapidly changing emission features in order to identify the onset of outburst events and obtain information about the geometry of the ejecta and how it changes over time. Short-lived line asymmetries display oscillation cycles (Stefl frequencies), which are compared to photometric and stable spectroscopic frequencies. All Be stars observed with sufficiently high cadence during an outburst are found to exhibit rapid oscillations of line asymmetry with a single frequency in the days following the start of the event. For a given star this circumstellar frequency may differ only slightly from event to event even when the outbursts they are associated with have different properties. These circumstellar frequencies are typically between 0.5 to 2 c/d, and are generally near photometric frequencies. They are slightly below prominent (generally stable) spectroscopic frequencies seen in photospheric absorption lines. The emission asymmetry cycles break down after roughly 5-10 cycles, with the emission line profile converging toward approximate symmetry shortly thereafter. In photometry, several frequencies typically emerge at relatively high amplitude at some point during the mass ejection process. In all observed cases, freshly ejected material was initially constrained within a narrow azimuthal range, indicating it was launched from a localized region on the stellar surface. The material orbits the star with a frequency consistent with the near-surface Keplerian orbital frequency. This material circularizes into a disk configuration after several orbital timescales. This is true whether or not there was a preexisting disk at the time of the observed outburst. We find no evidence for precursor phases prior to the ejection of mass in our sample. The several photometric frequencies that emerge during outburst are at least partially stellar in origin.2025A&A...699A..82Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/699/A82CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/699/A82https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/699/A82http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/699/A82https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/699/A82https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/699/A82http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/699/A82GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/699/A82/sources (List of studied sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/699/A82/sources?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/699/A82/sources?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/699/A82/sources?GETtext/xml+votable180.050000true208.4885-47.12816670.0055555555555555566/2851 12988 13268 14108 14217 14631 14912 22503 22895 22911 24142 37776 37894 39671 39863 43310 43365 43407 471213.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/699/A82?format=asciidefaultJ/A+A/699/A82/sourcesList of studied sourcesSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCommon IDmeta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainJ/A+A/699/A82/tablea1Target list and basic propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCommon IDmeta.id;meta.maincharHDHD numbermeta.idintTICTESS Input Catalog numbermeta.idlongSpTypeSpectral type from Simbadsrc.spTypecharVmagV-band magnitudemagphot.mag;em.opt.Vfloatvsini? Projected rotational velocitykm/sphys.veloc.rotatintnullablee_vsini? Projected rotational velocity errorkm/sstat.error;phys.veloc.rotatcharr_vsini? Projected rotational velocity reference (1)meta.refintnullablevsini2? Projected rotational velocity 2km/sphys.veloc.rotatintnullablee_vsini2? Projected rotational velocity 2 errorkm/sstat.errorintnullabler_vsini2? Projected rotational velocity 2 reference (1)meta.ref;pos.frameintnullableiInclination angledegsrc.orbital.inclination;pos.posAngchare_i? Inclination angle errordegstat.errorcharr_i? Inclination angle reference (1)meta.ref;pos.frameintnullablei2? Inclination angle 2degsrc.orbital.inclinationintnullablee_i2? Inclination angle 2 errordegstat.errorintnullabler_i2? Inclination angle 2 reference (1)meta.ref;pos.frameintnullablei3? Inclination angle 3degsrc.orbital.inclinationintnullablee_i3? Inclination angle 3 errordegstat.errorintnullabler_i3? Inclination angle 3 reference (1)meta.ref;pos.frameintnullableJ/A+A/699/A82/tablea2Flicker properties and quantitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCommon IDmeta.id;meta.maincharFlicType? Simplicity or complexity of the flickermeta.notecharEmFreqEmission oscillation frequencyd**-1em.freqfloate_EmFreq? Emission oscillation frequency errord**-1stat.errorfloatnullabler_EmFreqEmission oscillation frequency reference (1)meta.ref;pos.framechartb? duration of photometric build-up timedtime.durationfloatnullabletd? duration of photometric dissipation timedtime.durationfloatnullableAmp? Amplitude of photometric signal%src.var.amplitudefloatnullableMethodMethod for emission oscillation frequencymeta.notecharCycles? Number of cycles measuredctmeta.numbercharf_Cycles? Number of cycles measured flagmeta.codecharSpPulsFreq? Spectroscopic pulsation frequenciesd**-1em.freq;src.varcharr_SpPulsFreq? Spectroscopic pulsation frequencies reference (1)meta.ref;pos.framecharJ/A+A/699/A82/tablea3*Stellar parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCommon IDmeta.id;meta.maincharMassStellar masssolMassphys.massfloate_MassStellar mass errorsolMassstat.error;phys.massfloatReqStellar equatorial radiussolRadphys.size.radiusfloate_ReqStellar equatorial radius errorsolRadstat.errorfloatRpStellar polar radiussolRadphys.size.radiusfloate_RpStellar polar radius errorsolRadstat.errorfloatforbOrbital frequency at equatord**-1em.freq;src.varfloate_forbOrbital frequency at equator errord**-1stat.errorfloatfcritCritical rotation frequencyd**-1em.freq;src.varfloate_fcritCritical rotation frequency errord**-1stat.errorfloatfrotRotation frequencyd**-1em.freq;src.varfloate_frotRotation frequency errord**-1stat.errorfloatJ/A+A/699/A82/tablea4Observing logrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCommon IDmeta.id;meta.maincharNspecTESSSpectra taken during TESS observations (1)meta.notecharTESSSecTESS sectors used (1)obs.fieldcharNspTotalSpectra taken over date range totalmeta.notecharDateRangeDate range of spec obs (HJD-2457000)dtime.epochchar