J/AJ/159/119ivo://CDS.VizieR/J/AJ/159/119doi:10.26093/cds/vizier.51590119CDSPeters M.Wisniewski J.P.Williams B.F.Lomax J.R.Choi Y.Durbin M.,Johnson L.C.Lewis A.R.Lutz J.Sigut T.A.A.Wallach A.Dalcanton J.J.2021-03-04T06:50:11Z2020-05-18T07:05:54ZCDS support team

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

cds-question@unistra.frsurveysb-starshst-photometryvisible-astronomystellar-spectral-typesWe present results from a two epoch Hubble Space Telescope H{alpha} emission line survey of the Andromeda galaxy that overlaps the footprint of the Panchromatic Hubble Andromeda Treasury (PHAT) survey. We found 552 (542) classical Be stars and 8429 (8556) normal B-type stars in epoch 1 (epoch 2), yielding an overall fractional Be content of 6.15%{+/-}0.26% (5.96%{+/-}0.25%). The fractional Be content decreased with spectral subtype from ~23.6%{+/-}2.0% (~23.9%{+/-}2.0%) for B0-type stars to ~3.1%{+/-}0.34% (~3.4%{+/-}0.35%) for B8-type stars in epoch 1 (epoch 2). We observed a clear population of cluster Be stars at early fractional main-sequence lifetimes, indicating that a subset of Be stars emerge onto the zero-age main sequence as rapid rotators. Be stars are 2.8x rarer in M31 for the earliest subtypes compared to the Small Magellanic Cloud, confirming that the fractional Be content decreases in significantly more metal-rich environments (like the Milky Way and M31). However, M31 does not follow a clear trend of Be fraction decreasing with metallicity compared to the Milky Way, which may reflect that the Be phenomenon is enhanced with evolutionary age. The rate of disk-loss or disk-regeneration episodes we observed, 22%{+/-}2%/yr, is similar to that observed for seven other Galactic clusters reported in the literature, assuming these latter transient fractions scale by a linear rate. The similar number of disk-loss events (57) as disk-renewal events (43) was unexpected since disk dissipation timescales can be ~2x the typical timescales for disk build-up phases.2020AJ....159..119Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/119CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)J/A+AS/134/489 : Be stars in MC young clusters (Keller+ 1999)J/ApJ/622/1052 : byH{alpha} photometry of NGC 3766 (McSwain+, 2005)J/ApJS/161/118 : byH{alpha} photometry in open clusters (McSwain+, 2005)J/A+A/459/137 : Bright Be shell stars (Rivnius+, 2006)J/ApJ/652/458 : BVRH{alpha} phot. of candidates Be stars (Wisniewski+,2006)J/A+A/472/577 : NGC 330 Be stars and binaries (Martayan+, 2007)J/A+A/462/683 : Velocities in SMC field of NGC 330 (Martayan+, 2007)J/ApJ/700/1216 : Spectroscopy of Be stars in open clusters (McSwain+, 2009)J/A+A/509/A11 : H{alpha} emission-line objects SMC clusters (Martayan+,2010)J/ApJ/709/1306 : Spectropolarimetry of 60 Cyg and {pi} Aqr (Wisniewski+,2010)J/ApJ/752/95 : PHAT stellar cluster survey. I. Year 1 (Johnson+, 2012)J/A+A/553/A24 : Models for rotating stars (Georgy+, 2013)J/ApJ/786/120 : Spectropolarimetric survey classical Be stars (Draper+,2014)J/ApJ/792/121 : Photometric survey planetary nebulae in M31 (Veyette+, 2014)J/ApJS/215/9 : PHAT X. UV-IR photometry of M31 stars (Williams+, 2014)J/ApJ/802/127 : PHAT stellar cluster survey. II. AP catalog (Johnson+, 2015)J/ApJ/827/33 : PHAT. XVI. Star cluster masses and ages (Johnson+, 2016)J/AJ/153/252 : Photo. variability of BeSS-KELT stars (Labadie-Bartz+,2017)J/MNRAS/465/4180 : H{alpha} stars in M31 HST photometry (Prichard+, 2017)J/A+A/610/A70 : 28 Cygni BRITE and SMEI satellite photometry (Baade+, 2018)J/AJ/155/50 : WISE photo. of Be stars young open clusters (Granada+, 2018)J/AJ/155/53 : Outbursts & disk variability Be stars (Labadie-Bartz+,2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/159/119https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/159/119http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/159/119https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/159/119https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/159/119http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/159/119GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/159/119/table1 (Summary of HST observations of M31 from GO-13857)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/159/119/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/159/119/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/159/119/table1?GETtext/xml+votable180.050000true11.347416741.77013890.005555555555555556Cone search capability for table J/AJ/159/119/table8 (Source catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/159/119/table8?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/159/119/table8?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/159/119/table8?GETtext/xml+votable180.050000true11.42365702667141.8627450234330.0055555555555555566/2623 2666 2709 27522.238682544986967e-19 4.747794194386724e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/159/119?format=asciiOpticaldefaultJ/AJ/159/119/table1Summary of HST observations of M31 from GO-13857Exp625[750] Exposure time for F625Wstime.expointrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNsNumber of stars observed in this field (link to Table 8)meta.numberintnullableEpoch[1/2] Epoch numbermeta.number;time.epochintPntg[1/6] Pointingsobs.fieldintprimaryObs[2014/2015] Year of observationtime.epochInstCamera used ("WFC3" or "ACS/WFC")meta.id;instrcharRAJ2000[0] Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000[41] Degree of declination (J2000)pos.eq.dec;meta.mainExp658[3850] Exposurer time for F658Nstime.expointJ/AJ/159/119/table8Source catalogCl[0/5933] Best estimate for cluster membership (0=field star) (1)meta.id.parentintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPntg[4/6] Pointingsobs.fieldintEpoch[1/2] Epochmeta.id;obsintIndex[35/2256863] Indexmeta.idintRAJ2000[11.12/11.46] Right Ascension (J2000) from Williams+ (2014, J/ApJS/215/9)degpos.eq.ra;meta.mainindexedDEJ2000[41.39/42] Declination (J2000) from Williams+ (2014, J/ApJS/215/9)degpos.eq.dec;meta.mainindexedF475W[20.3/26.8] HST/WFC3 F475W magnitude from Williams+ (2014, J/ApJS/215/9)magphot.mag;em.opt.Bfloate_F475W[0.002/0.2] 1{sigma} uncertainty in F475Wmagstat.errorfloatF625W[20.2/25.6] HST/ACS-WFC F625W magnitude from this workmagphot.mag;em.opt.Rfloate_F625W[0.004/0.1] 1{sigma} uncertainty in F625Wmagstat.errorfloatF658N[20/24.7] HST/ACS-WFC F658N magnitude from this workmagphot.mag;em.opt.Rfloate_F658N[0.008/0.2] 1{sigma} uncertainty in F658Nmagstat.errorfloatF814W[20.2/25.8] HST/WFC3 F814W magnitude from Williams+ (2014, J/ApJS/215/9)magphot.mag;em.opt.Ifloate_F814W[0.003/0.2] 1{sigma} uncertainty in F814Wmagstat.errorfloatlogTeff[4/4.6] Stellar effective surface temperaturelog(K)phys.temperature.effectivefloatlogg50[2.9/4.5] Surface gravity, 50th percentilelog(cm.s**-2)phys.gravityfloatlogg84[3.7/4.5] Surface gravity, 84th percentilelog(cm.s**-2)phys.gravityfloatBe*Is the star a classical Be star?meta.codecharSpTBest estimate for the spectral type based on logTeffsrc.spTypecharVar*Exhibit variability between epochs (2)src.varcharW14Display data from PHAT X. (Williams+, 2014, J/ApJS/215/9) within 0.1"meta.ref.urlchar