J/A+A/685/A124ivo://CDS.VizieR/J/A+A/685/A124doi:10.26093/cds/vizier.36850124CDSJadlovsky D.Granzer T.Weber M.Kravchenko K.Krticka J.Dupree A.K.,Chiavassa A.Strassmeier K.G.PoppenhagerK.2024-11-29T20:02:15Z2024-05-17T18:53:31ZCDS support team

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

cds-question@unistra.frsupergiant-starsvisible-astronomyspectroscopyradial-velocityBetelgeuse, a red supergiant star of semi-regular variability, underwent a historical minimum of brightness in February 2020, the Great Dimming. Even though the brightness has returned to the values prior to the Great Dimming by now, it continues to exhibit highly unusual behavior. Understanding the long-term atmospheric motions of Betelgeuse and its variability could be a clue to the nature of the Great Dimming and the mass-loss process in red supergiants. Our goal is to study long-term dynamics of the photosphere, including during the Great Dimming. We applied the tomographic method, which allows different layers in the stellar atmosphere to be probed in order to reconstruct depth-dependent velocity fields. The method is based on the construction of spectral masks by grouping spectral lines from specific optical depths. These masks are cross-correlated with the observed spectra to recover the velocity field inside each atmospheric layer. We obtained about 2800 spectra during the past 15 years, observed with the STELLA robotic telescope in Tenerife. We analyzed the variability of 5 different layers of Betelgeuses photosphere. We found phase shift between the layers, as well as between the variability of velocity and photometry. The time variations of the widths of the cross-correlation function reveal propagation of two shock waves during the Great Dimming. For about 2 years after the Dimming, the time scale of variability was different between the inner and outer photospheric layers. By 2022, all the layers seemingly started to follow a similar behavior as before the Dimming, but pulsating with higher frequency corresponding with the first overtone. Combination of the extensive high-resolution spectroscopic data set with the tomographic method revealed the variable velocity fields in the photosphere of Betelgeuse, for the first time in such detail. We were also able to find new insights related to the Great Dimming event and its aftermath, namely the discovery of another shock wave and the subsequent rearrangement of the photosphere.2024A&A...685A.124Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/685/A124CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/902/63 : SMEI photometry of Betelgeuse (Joyce+, 2020)J/ApJ/905/34 : 2017-2020 photometry of Betelgeuse (Harper+, 2020)J/A+A/650/L17 : HERMES spectra of Betelgeuse (Kravchenko+, 2021)J/other/Nat/594.365 : Betelgeuse during its Great Dimming (Montarges+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/685/A124https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/685/A124http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/685/A124https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/685/A124https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/685/A124http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/685/A124GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/685/A124/list (List of fits spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/685/A124/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/685/A124/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/685/A124/list?GETtext/xml+votable180.050000true88.79295837.40705560.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/685/A1246/23611https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/685/A124?format=asciiOpticaldefaultJ/A+A/685/A124/rvmask1RVs determined with mask 1FileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoublespShow the spectrummeta.ref.urlcharJ/A+A/685/A124/rvmask2RVs determined with mask 2recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoublespShow the spectrummeta.ref.urlcharFileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharJ/A+A/685/A124/rvmask3RVs determined with mask 3recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoublespShow the spectrummeta.ref.urlcharFileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharJ/A+A/685/A124/rvmask4RVs determined with mask 4spShow the spectrummeta.ref.urlcharFileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoubleJ/A+A/685/A124/rvmask5RVs determined with mask 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoublespShow the spectrummeta.ref.urlcharFileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharJ/A+A/685/A124/rvnomaskRVs determined with the original templaterecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Daydtime.epoch;pos.heliocentricdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVUncertainty on radial velocitykm/sstat.errordoubleGFWHMFull width at half maximumkm/sspect.line.widthdoubleSNRSignal-to-noise ratiostat.snrdoublespShow the spectrummeta.ref.urlcharFileNameSpectrum file name, in subdirectory fitsmeta.id;meta.fitscharJ/A+A/685/A124/listList of fits spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintNzNumber of slicesmeta.numberintObs.dateObservation datestime.epoch;obsnullablesizeSize of FITS fileKibytephys.size;meta.fitsintspShow the spectrummeta.ref.urlcharFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar