J/ApJ/863/79ivo://CDS.VizieR/J/ApJ/863/79doi:10.26093/cds/vizier.18630079CDSContreras Ramos R.Minniti D.Gran F.Zoccali M.Alonso-Garcia J.,Huijse P.Navarro M.G.Rojas-Arriagada A.Valenti E.2021-02-23T08:05:10Z2019-08-30T15:17:58ZCDS support team

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

cds-question@unistra.frvariable-starsinfrared-photometryproper-motionsmetallicitystellar-distanceextinctiongalactic-centerDeep near-IR images from the VISTA Variables in the Via Lactea (VVV) Survey were used to search for RR Lyrae stars within 100 arcmin from the Galactic Center. A large sample of 960 RR Lyrae of type ab (RRab) stars were discovered. A catalog is presented featuring the positions, magnitudes, colors, periods, and amplitudes for the sample, in addition to estimated reddenings, distances, and metallicities, and measured individual relative proper motions. We use the reddening-corrected Wesenheit magnitudes, defined as W_Ks_=Ks-0.428x(J-Ks), in order to isolate bona fide RRL belonging to the Galaxy Center, finding that 30 RRab are foreground/background objects. We measure a range of extinctions from A_Ks_=0.19 to 1.75mag for the RRab in this region, finding that large extinction is the main cause of the sample incompleteness. The mean period is P=0.5446+/-0.0025d, yielding a mean metallicity of [Fe/H]=-1.30+/-0.01 ({sigma}=0.33)dex for the RRab sample in the Galactic Center region. The median distance for the sample is D=8.05+/-0.02kpc. We measure the RRab surface density using the less reddened region sampled here, finding a density of 1000 RRab/sq deg at a projected Galactocentric distance R_G_=1.6deg. Under simple assumptions, this implies a large total mass (M>10^9^M_{sun}_) for the old and metal-poor population contained inside RG. We also measure accurate relative proper motions, from which we derive tangential velocity dispersions of {sigma}V_l_=125.0 and {sigma}V_b_=124.1km/s along the Galactic longitude and latitude coordinates, respectively. The fact that these quantities are similar indicate that the bulk rotation of the RRab population is negligible, and implies that this population is supported by velocity dispersion. In summary, there are two main conclusions of this study. First, the population as a whole is no different from the outer bulge RRab, predominantly a metal-poor component that is shifted with respect to the Oosterhoff type I population defined by the globular clusters in the halo. Second, the RRab sample, as representative of the old and metal-poor stellar population in the region, has high velocity dispersions and zero rotation, suggesting a formation via dissipational collapse.2018ApJ...863...79Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/863/79CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)II/348 : VISTA Variable in the Via Lactea Survey DR2 (Minniti+, 2017)J/AJ/108/1016 : Kinematics of local RR lyrae stars. I. (Layden, 1994)J/A+A/486/177 : Bulge field stars from FLAMES-GIRAFFE spectra (Zoccali+, 2008)J/MNRAS/399/1709 : Near-infrared survey of Miras (Matsunaga+, 2009)J/ApJ/724/799 : RR Lyrae variables in M33. II. (Yang+, 2010)J/AJ/139/357 : Variable stars in NGC 5286 (Zorotovic+, 2010)J/AcA/61/1 : VI LCs of Galactic Bulge RR Lyrae (Soszynski+, 2011)J/MNRAS/441/1230 : RRLyr stars in the Catalins Sky Survey (CS2) (Abbas+, 2014)J/AcA/64/177 : VI LCs of Galactic Bulge RR Lyrae (Soszynski+, 2014)J/AJ/149/99 : VVV globulars I. 2MASS-GC 02, Terzan 10 (Alonso-Garcia+, 2015)J/ApJ/807/127 : 70 RR Lyrae stars in the LMC bar (Muraveva+, 2015)J/MNRAS/446/2251 : Southern Catalina Survey type-ab RR Lyrae (Torrealba+, 2015)J/A+A/591/A145 : VVV Survey outer bulge RRab stars (Gran+, 2016)J/ApJ/821/L25 : Bulge RR Lyrae RVel Assay (BRAVA-RR) (Kunder+, 2016)J/AJ/153/179 : VVV Survey RR Lyrae in Southern Gal. plane (Minniti+, 2017)J/A+A/604/A120 : omega Cen RR Lyrae and SX Phoenicis stars (Navarrete+, 2017)J/A+A/599/A12 : [Fe/H] & kinematics of Galactic bulge fields (Zoccali+, 2017)J/ApJ/857/54 : JHKs photometry of VVV RR Lyrae stars (Dekany+, 2018)J/other/ApSS/363.127 : Bulge RR Lyrae VVVDR4 photometry (Majaess+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/863/79https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/863/79http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/863/79https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/863/79https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/863/79http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/863/79GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/863/79/rrabcand (RR Lyrae photometric observations and relative proper motions and measured stellar parameters (tables 1 and 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/79/rrabcand?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/79/rrabcand?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/79/rrabcand?GETtext/xml+votable180.050000true266.171649-28.8634760.0055555555555555565/7206 7207 6/28819 28822 28823 28848 28849 28851 28852 28853 28854 28872 288748.643406281242892e-20 2.393642124494231e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/863/79?format=asciiInfrareddefaultJ/ApJ/863/79/rrabcandRR Lyrae photometric observations and relative proper motions and measured stellar parameters (tables 1 and 2)Per[0.3/1] Perioddtime.perioddoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDRR Lyrae identifiermeta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latKsmag[12.6/16.1] VISTA Ks band magnitudemagphot.mag;em.IR.KfloatHmag[13.2/17.8]? VISTA H band magnitudemagphot.mag;em.IR.HfloatnullableJmag[14/20.4]? VISTA J band magnitudemagphot.mag;em.IR.JfloatnullableYmag[14.6/21.1]? VISTA Y band magnitudemagphot.mag;em.IR.JfloatnullableZmag[15/21.7]? VISTA Z band magnitudemagphot.mag;em.opt.IfloatnullablepmGLON[-11/11.1]? Relative proper motion along GLON *cos(GLAT)mas/yrpos.pmfloatnullablee_pmGLON[0.4/5]? Uncertainty in pmGLONmas/yrstat.errorfloatnullablepmGLAT[-14.6/]? Relative proper motion along GLATmas/yrpos.pmfloatnullablee_pmGLAT[0.3/5.3]? Uncertainty in pmGLATmas/yrstat.errorfloatnullableE(J-Ks)[0.4/4.2]? The J-Ks color indexmagphot.color;em.IR;em.IRfloatnullableAKs[0.1/1.8]? The Ks band extinctionmagphys.absorptionfloatnullableDM[12.6/15.5]? Intrinsic distance modulusmagphot.mag.distModfloatnullableDist[3.3/12.5]? Distance from the Sunkpcpos.distance;pos.heliocentricfloatnullableKsAmp[0.1/0.6] The Ks band amplitudemagsrc.var.amplitudefloat[Fe/H][-2.6/-0.1] Metallicitylog(Sun)phys.abund.ZfloatS14Display data from Soszynski+, 2014, J/AcA/64/177 within 0.5"meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexed