J/ApJ/871/103ivo://CDS.VizieR/J/ApJ/871/103doi:10.26093/cds/vizier.18710103CDSGautam A.K.Do T.Ghez A.M.Morris M.R.Martinez G.D.Hosek M.W.,Lu J.R.Sakai S.Witzel G.Jia S.Becklin E.E.Matthews K.2025-03-03T20:10:59Z2025-01-22T11:06:31ZCDS support team

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

cds-question@unistra.frgalactic-centerinfrared-photometryearly-type-starslate-type-starsabsolute-magnitudeeclipsing-binary-starsWe present an ~11.5yr adaptive optics (AO) study of stellar variability and search for eclipsing binaries in the central ~0.4pc (~10") of the Milky Way nuclear star cluster. We measure the photometry of 563 stars using the Keck II Near Infrared Camera 2 (NIRC2) imager (K'-band, {lambda}_0_=2.124{mu}m). We achieve a photometric uncertainty floor of {Delta}m_K'_~0.03 (~3%), comparable to the highest precision achieved in other AO studies. Approximately half of our sample (50%{+/-}2%) shows variability: 52%{+/-}5% of known early-type young stars and 43%{+/-}4% of known late-type giants are variable. These variability fractions are higher than those of other young, massive star populations or late-type giants in globular clusters, and can be largely explained by two factors. First, our experiment time baseline is sensitive to long-term intrinsic stellar variability. Second, the proper motion of stars behind spatial inhomogeneities in the foreground extinction screen can lead to variability. We recover the two known Galactic center eclipsing binary systems: IRS16SW and S4-258(E60). We constrain the Galactic center eclipsing binary fraction of known early-type stars to be at least 2.4%{+/-}1.7%. We find no evidence of an eclipsing binary among the young S-stars nor among the young stellar disk members. These results are consistent with the local OB eclipsing binary fraction. We identify a new periodic variable, S2-36, with a 39.43days period. Further observations are necessary to determine the nature of this source.2019ApJ...871..103Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/871/103CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/470/864 : JHKL photometry of the Galactic Center (Blum+, 1996)J/ApJ/523/248 : Variable stars in the Galactic center (Ott+, 1999)J/A+A/373/608 : Early-type stars towards Galactic Center. II. (Dufton+,2001)J/A+A/426/81 : Kinematic analysis of the Minispiral (Paumard+, 2004)J/A+A/433/117 : L- & M-band imaging of the Galactic Center (Viehmann+, 2005)J/MNRAS/370/1979 : JHKs photometry T2Cs in globular clusters (Matsunaga+, 2006)J/ApJ/643/1011 : Early-type stars in the center of the Galaxy (Paumard+,2006)J/ApJ/659/1241 : Stellar variability in Galactic Center (Rafelski+, 2007)J/ApJ/697/1741 : Warped disks of YSOs in Galactic center (Bartko+, 2009)J/ApJ/703/1323 : Spectroscopy of stars in Galaxy's nuclear cluster (Do+ 2009)J/MNRAS/399/1709 : Near-infrared survey of Miras (Matsunaga+, 2009)J/ApJ/723/1195 : SAGE AGB candidates (Riebel+, 2010)J/A+A/511/A18 : NIR observations of stars near SgrA* (Schoedel+, 2010)J/ApJ/725/331 : Astrometry in the Galactic Center (Yelda+, 2010)J/A+A/537/A146 : Stellar models (rotation 0.8<M<120, Z=0.014) (Ekstrom+,2012)J/ApJ/764/154 : Stellar populations in the central 0.5pc. I. (Do+, 2013)J/ApJ/779/L6 : 3D kinematic obs. of stars in Galactic Centre (Do+, 2013)J/A+A/562/A125 : OGLE-III SMC tars VI light curves (Kourniotis+, 2014)J/MNRAS/442/2381 : Variable stars in M4 primary field (Nascimbeni+, 2014)J/ApJ/783/131 : Kinematic of stars in Galactic center (Yelda+, 2014)J/AJ/150/132 : JHK photometry of 1203 variables in ONC (Rice+, 2015)J/ApJ/808/106 : NIR spectroscopic obs. in Galactic Center (Stostad+, 2015)J/ApJ/830/17 : Galactic Center secondary IR astrometric std (Boehle+, 2016)J/A+A/585/A141 : Galactic center early-type stars catalog (Grosboel, 2016)J/A+A/592/A120 : Variable stars in NGC 6715 (Figuera Jaimes+, 2016)J/A+A/588/A128 : Variable stars in globular clusters (Figuera Jaimes+, 2016)J/MNRAS/470/3427 : Variable Stars in the Galactic Center (Dong+, 2017)J/ApJ/854/12 : 16yrs of radial velocity measurements of S0-2 (Chu+, 2018)J/A+A/609/A26 : Galactic Center old stars distribution (Gallego-Cano+, 2018)J/A+A/610/A83 : GALACTICNUCLEUS: JHKs imaging survey (Nogueras-Lara+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/871/103https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/871/103http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/871/103https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/871/103https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/871/103http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/871/103GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/871/103/table12 (Catalog of stars in sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/871/103/table12?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/871/103/table12?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/871/103/table12?GETtext/xml+votable180.050000true266.41715028-29.007672220.0055555555555555566/28830https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/871/103?format=asciiInfrareddefaultJ/ApJ/871/103/table12Catalog of stars in sampleSimbadNameSimbad column added by the CDSmeta.idcharnullablermsJ/ApJ/871/103/table1Observations used in this workeKmag[0.01/0.08] Error on relative K' magnitude (2)magstat.error;phot.mag;em.IR.KfloateAstro[0.29/1.35] Error on astrometric data (2)masstat.error;posfloatFWHM[53.1/88.3] Full Width at Half Maximum (3)masspect.line.widthfloatStrehl[0.15/0.43] Strehl ratio (3)stat.fit.paramfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs[2006/2017] UTC year of observationtime.epoch;obsf_Obs[a] Flag on Obs.D (1)meta.codecharMJD[53858/57992] Modified Julian Date of observationdtime.epochdoubleFrame[9/193] Frame numberobs.fieldintNdet[652/2514] Number of stars detectedmeta.numberintNs[361/524] Number of stars in samplemeta.numberinteKMAG[0.15/0.22] Error on absolute K' magnitude (2)magstat.error;phys.magAbs;em.IR.Kfloat