J/ApJ/902/24ivo://CDS.VizieR/J/ApJ/902/24doi:10.26093/cds/vizier.19020024CDSDorn-Wallenstein T.Z.Levesque E.M.Neugent K.F.,Davenport J.R.A.Morris B.M.Gootkin K.2022-03-14T07:45:17Z2022-03-08T17:02:46ZCDS support team

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

cds-question@unistra.frsupergiant-starsphotometryproper-motionsvisible-astronomyMassive stars briefly pass through the yellow supergiant (YSG) phase as they evolve redward across the H-R diagram and expand into red supergiants (RSGs). Higher-mass stars pass through the YSG phase again as they evolve blueward after experiencing significant RSG mass loss. These post-RSG objects offer us a tantalizing glimpse into which stars end their lives as RSGs and why. One telltale sign of a post-RSG object may be an instability to pulsations, depending on the star's interior structure. Here we report the discovery of five YSGs with pulsation periods faster than 1 day, found in a sample of 76 cool supergiants observed by the Transiting Exoplanet Survey Satellite (TESS) at a two-minute cadence. These pulsating YSGs are concentrated in an H-R diagram region not previously associated with pulsations; we conclude that this is a genuine new class of pulsating star, fast yellow pulsating supergiants (FYPSs). For each FYPS, we extract frequencies via iterative prewhitening and conduct a time-frequency analysis. One FYPS has an extracted frequency that is split into a triplet, and the amplitude of that peak is modulated on the same timescale as the frequency spacing of the triplet; neither rotation nor binary effects are likely culprits. We discuss the evolutionary status of FYPS and conclude that they are candidate post-RSGs. All stars in our sample also show the same stochastic low-frequency variability found in hot OB stars and attributed to internal gravity waves. Finally, we find four {alpha} Cygni variables in our sample, of which three are newly discovered.2020ApJ...902...24Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/902/24CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)J/MNRAS/402/2087 : Optical polarization of OJ 287 in 2005-2009J/A+AS/101/421 : uvby-beta photometry of GP And (Rodriguez+ 1993)J/AJ/106/591 : OP Survey of Halo early-type stars (Rodgers+ 1993)J/A+AS/106/141 : Photometry of luminous blue variables (Spoon+ 1994)J/AJ/121/2148 : Spectral types for 372 A, F & G stars (Gray+, 2001)J/A+A/374/712 : Photometric observations of comets (Szabo+, 2001)J/AJ/125/277 : High PMs in central Orion nebula (O'dell+, 2003)J/ApJ/680/130 : MIR colors of AGNs in the MUSYC ECDF-S (Cardamone+, 2008)J/AJ/138/1003 : IR photometry of massive LMC stars (Bonanos+, 2009)J/MNRAS/395/1409 : Type II-P SN progenitor constraints (Smartt+, 2009)J/A+A/502/937 : Radial velocities of 9 O-type stars (Mahy+, 2009)J/ApJ/719/1784 : Yellow supergiants in the SMC (Neugent+, 2010)J/A+A/533/A4 : CoRoT photometry of three O-type stars (Blomme+, 2011)J/A+A/537/A146 : Stellar models with rotation. 0.8<M<120 (Ekstrom+, 2012)J/ApJ/749/177 : Yellow and red supergiants in the LMC (Neugent+, 2012)J/other/Sci/337.444 : RV curves of Galactic massive O stars (Sana+, 2012)J/A+A/544/A53 : Long-term phot. & spectroscopy of EE Cep (Galan+, 2012)J/A+A/560/A16 : Comparison of evolutionary tracks (Martins+, 2013)J/A+A/550/A107 : RV catalogue of O stars in 30 Doradus (Sana+, 2013)J/A+A/556/A52 : {gamma} Dor stars from Kepler (Tkachenko+, 2013)J/MNRAS/434/2418 : [Fe/H] of short-period Gal. Cepheids (Klagyivik+, 2013)J/A+A/567/A68 : Gas accretion in nearby spiral gal. (Di Teodoro+, 2014)J/AJ/156/102 : TESS Input Cat. & Candidate Target List (Stassun+, 2018)J/A+A/629/A100 : MUSE library of stellar spectra (Ivanov+, 2019)J/ApJ/872/L9 : TESS obs. of massive O and B stars (Pedersen+, 2019)J/A+A/640/A36 : OB stars TESS phot. & high-res. spec. (Bowman+, 2020)J/ApJ/889/44 : UKIRT obs. of red supergiants in M31 (Neugent+, 2020)J/ApJ/747/L19 : A search for type Ia SNR B0519-69.0 progenitorshttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/902/24https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/902/24http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/902/24https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/902/24https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/902/24http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/902/24GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/902/24/sample (TESS parameters and positions in the HR diagram of the cool supergiants (Table 1) and fit parameters from Equation (1) (Table 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/902/24/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/902/24/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/902/24/sample?GETtext/xml+votable180.050000true174.10924243-61.319446110.0055555555555555566/1111 3253 3256-3258 3272 3275 3324 3604 3621 3632 3634 3718 14253 14264 14270 14295 14302 14319 14357 14617 14619 14623 14644 14689 23880 24486 33055 33078 33091-33092 33094 33098 33100 33112 33120 33122 33124 33128 37894 37901 37912 37927-37930 38016 38022 38024 40635 41704 42154 42435https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/902/24?format=asciiOpticaldefaultJ/ApJ/902/24/sampleTESS parameters and positions in the HR diagram of the cool supergiants (Table 1) and fit parameters from Equation (1) (Table 2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameCommon Namemeta.id;meta.maincharTIC[13249363/467450857] TESS input catalog IDmeta.idlongRAJ2000[17/358.3] TIC right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[-70.05/64.4] TIC declination (J2000)degpos.eq.dec;meta.mainpmRA[-7.45/2.32] TIC proper motion in right ascensionmas/yrpos.pm;pos.eq.rafloatpmDE[-6.28/3.64] TIC proper motion in declinationmas/yrpos.pm;pos.eq.decfloatTmag[4.1/11.97] TESS magnitudemagphot.mag;em.optfloatlogTeff[3.53/4.04] log of surface temperature (1)log(K)phys.temperaturefloatlogLstar[4.04/5.47] log of luminosity (1)log(solLum)phys.luminosityfloatRefSource of logTeff and logLstar (2)meta.bibcharHRTypeType from HR diagram: "R"=RSG (48 occurrences); Y=YSG (28 occurrences)meta.code.classcharVarTypeVariable type: {alpha} Cygni or new fast yellow pulsating supergiant ("FYPS")meta.note;src.morph.typealpha0[7.6/2202] Parameter {alpha}_0_, from Equation 1 (3)stat.fit.paramdoublee_alpha0[0.27/261] Uncertainty in alpha0stat.fit.paramdoubletau[0.03/2.6] Parameter {tau}, from Equation 1 (3)dstat.fit.paramfloate_tau[0.0014/0.6] Uncertainty in taudstat.fit.paramfloatgamma[1.26/3.04] Parameter {gamma} from Equation 1 (3)stat.fit.paramfloate_gamma[0.005/0.15] Uncertainty in gammastat.fit.paramfloatalphaw[1.55/52.67] Parameter {alpha}_w_, from Equation 1 (3)stat.fit.paramfloate_alphaw[0.0006/0.09] Uncertainty in alphawstat.fit.paramfloatN12Display data from Neugent+, 2012, J/ApJ/749/177meta.ref.urlintnullableSimbadSimbad column added by the CDSstat.fit.paramchar