Altair light curvesJ/A+A/687/A259ivo://CDS.VizieR/J/A+A/687/A259doi:10.26093/cds/vizier.36870259CDSRieutord M.Reese D.R.Mombarg J.S.G.Charpinet S.2024-11-29T20:03:55Z2024-07-18T08:51:21ZCDS support team
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
cds-question@unistra.frearly-type-starsphotometryvisible-astronomyUnderstanding the effects of rotation in stellar evolution is key to modelling early-type stars, half of which have equatorial velocities over 100km/s. The nearby star Altair is an example of such fast-rotating stars, and furthermore, it has the privilege of being modelled by a detailed 2D concordance model that reproduces most of its observables. The aim of this paper is to include new asteroseismic frequencies to improve our knowledge of Altair, especially its age. We processed images of Altair obtained during July 2022 by the Transiting Exoplanet Survey Satellite using the halo photometry technique to obtain its light curve over this observation period. By analysing the light curve, we derived a set of 22 new frequencies in the oscillation spectrum of Altair and confirmed 12 previously known frequencies. Compared with model predictions, we could associate ten frequencies with ten axisymmetric modes. This identification is based on the modelled visibility of the modes. Moreover, nine of the modelled frequencies can be adjusted to simultaneously match their corresponding observed frequencies, once the core hydrogen mass fraction of the concordance model is set to X_core_/X_ini_=~0.972, with X_ini_=0.739. Using the combined results of a 1D MESA model computing the pre-main sequence and a 2D time-dependent ESTER model computing the main sequence, we find that this core hydrogen abundance sets the age of Altair to 88+/-10Myrs, which is slightly younger than previous estimates.2024A&A...687A.259Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/687/A259CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/687/A259https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/687/A259http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/687/A259https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/687/A259https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/687/A259http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/687/A259GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+A/687/A259/unfiltRaw result halo photometry subtractedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTimeTime (Barycentric TESS Julian Date) origin is t0=2769.8986175dmeta.ref;time.epochdoubleindexedFluxRelative variation of the fluxphot.flux;arith.ratiodouble
J/A+A/687/A259/filt*Filtered photometryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTimeTime (Barycentric TESS Julian Date) origin is t0=2769.8986175dmeta.ref;time.epochdoubleindexedFluxRelative variation of the fluxphot.flux;arith.ratiodouble