J/ApJ/857/54ivo://CDS.VizieR/J/ApJ/857/54doi:10.26093/cds/vizier.18570054CDSDekany I.Hajdu G.Grebel E.K.Catelan M.Elorrieta F.Eyheramendy S.,Majaess D.Jordan A.2023-08-16T13:12:17Z2019-03-19T08:30:37ZCDS support team

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

cds-question@unistra.frvariable-starsinfrared-photometrystellar-distancesurveysgalaxy-planesmilky-way-galaxyRR Lyrae stars (RRLs) are tracers of the Milky Way's fossil record, holding valuable information on its formation and early evolution. Owing to the high interstellar extinction endemic to the Galactic plane, distant RRLs lying at low Galactic latitudes have been elusive. We attained a census of 1892 high-confidence RRLs by exploiting the near-infrared photometric database of the VVV survey's disk footprint spanning ~70{deg} of Galactic longitude, using a machine-learned classifier. Novel data-driven methods were employed to accurately characterize their spatial distribution using sparsely sampled multi-band photometry. The RRL metallicity distribution function (MDF) was derived from their K_s_-band light-curve parameters using machine-learning methods. The MDF shows remarkable structural similarities to both the spectroscopic MDF of red clump giants and the MDF of bulge RRLs. We model the MDF with a multi-component density distribution and find that the number density of stars associated with the different model components systematically changes with both the Galactocentric radius and vertical distance from the Galactic plane, equivalent to weak metallicity gradients. Based on the consistency with results from the ARGOS survey, three MDF modes are attributed to the old disk populations, while the most metal-poor RRLs are probably halo interlopers. We propose that the dominant [Fe/H] component with a mean of -1dex might correspond to the outskirts of an ancient Galactic spheroid or classical bulge component residing in the central Milky Way. The physical origins of the RRLs in this study need to be verified by kinematical information.2018ApJ...857...54Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/857/54CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/348 : VISTA Variable in the Via Lactea Survey DR2 (Minniti+, 2017)J/AJ/155/171 : RR Lyrae stars in and around NGC 6441 (Kunder+, 2018)J/other/ApSS/363.127 : Bulge RR Lyrae VVVDR4 photometry (Majaess+, 2018)J/A+A/604/A120 : omega Cen RR Lyrae and SX Phoenicis stars (Navarrete+, 2017)J/AJ/153/179 : VVV Survey RR Lyr in Southern Galactic plane (Minniti+, 2017)J/AJ/153/96 : Standard Galactic field RR Lyrae. I. Phot. (Monson+, 2017)J/AJ/152/170 : RRLs in globulars. IV. UBVRI phot. in Omega Cen (Braga+, 2016)J/ApJ/821/L25 : Bulge RR Lyrae RV Assay (BRAVA-RR) (Kunder+, 2016)J/ApJ/807/127 : 70 RR Lyrae stars data in the LMC bar (Muraveva+, 2015)J/AcA/64/177 : VI light curves of Galactic Bulge RR Lyrae (Soszynski+, 2014)J/AJ/146/21 : LINEAR. II. Catalog of RR Lyrae stars (Sesar+, 2013)J/MNRAS/428/3660 : ARGOS line list {lambda}8395-8830{AA} (Freeman+, 2013)J/ApJ/763/32 : Galactic halo RRab stars from CSS (Drake+, 2013)J/ApJ/678/851 : RR Lyrae survey in the Galactic Halo (Keller+, 2008)J/AJ/129/2714 : JHK photometry of M92 variable stars (Del Principe+, 2005)J/A+A/312/111 : [Fe/H] from RR Lyrae light curves (Jurcsik+, 1996)J/AJ/108/1016 : Kinematics of local RR lyrae stars. I. (Layden, 1994)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/857/54https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/857/54http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/857/54https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/857/54https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/857/54http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/857/54GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/857/54/table1 (Parameters of the RR Lyrae stars in our fiducial sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/857/54/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/857/54/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/857/54/table1?GETtext/xml+votable180.050000true174.732625-63.37716670.0055555555555555564/2610 2638 2652 5/9473 9476-9477 10398-10399 10413 10417-10419 10421-10422 10424 10439 10444-10445 10449-10453 10455-10456 10464 10538-10539 10541-10543 10551 10556-10557 10594-10597 10599-10600 10625 10754-10755 10760 6/37891 37897 37901 37952 41470-41471 41583 41591 41629-41631 41645 41647 41649-41651 41656-41658 41661-41663 41665 41667 41680-41681 41683 41692 41700-41702 41704-41705 41742-41743 41751 41753-41755 41784-41786 41788 41794-41795 41817-41819 41828-41830 41860 42151 42162-42163 42190-42191 42201-42203 42232-42233 42236 42303 42346-42347 42350-42351 42362 42371 42374-42375 42392 42394-42395 42404-42406 42416-42417 42420-42421 42448 42464-42465 42468-42469 42496-42497 42499 42504-42505 42508 42512-42514 42516-42517 42560 43009-43014 43025-43027 43032 43034 43044 43046 43048-430507.952274030004205e-20 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/857/54?format=asciiInfrareddefaultJ/ApJ/857/54/table1Parameters of the RR Lyrae stars in our fiducial samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNpNumber of photometry measurements for this star (link to table 2)meta.numberintnullableSeq[1/1892] Running sequence numbermeta.id;meta.mainintprimaryRAJ2000[11/17] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[35/65] Degree of Declination (J2000)pos.eq.dec;meta.mainScore[0.6/0.9] Classification scoremeta.code.qualfloatPer[0.3/0.9] Pulsation perioddtime.perioddoubleAp[1/5] Optimal aperturephys.angSize;instr.fovintKsmagAvg[11/16.4] Magnitude of Ks intensity meanmagphot.mag;em.IR.Kfloatsigma[0.006/0.2] Standard deviation of the Ks residualmagstat.stdev;phot.magfloatS/N[27/315] Signal-to-noise ratio of the Ks light-curvestat.snrfloatAmpKs[0.07/0.6] Total amplitude in the Ks bandmagsrc.var.amplitudefloatSimbadSimbad column added by the CDSmeta.ref.urlcharE(J-Ks)[0/6.3] J-Ks color excessmagphot.color.excessfloatJmagAvg[11.3/19.5] Magnitude of J intensity meanmagphot.mag;em.IR.JfloatHmagAvg[11.2/17]? Magnitude of H intensity meanmagphot.mag;em.IR.HfloatnullableU1[0.3/1.2] Amplitude of first Ks principal componentmagsrc.var.amplitudefloatU2[-0.5/0.7] Amplitude of second Ks principal componentmagsrc.var.amplitudefloatU3[-0.2/0.2] Amplitude of third Ks principal componentmagsrc.var.amplitudefloatU4[-0.1/0.2] Amplitude of fourth Ks principal componentmagsrc.var.amplitudefloat[Fe/H]Ks[-3.4/-0.01] Metallicity predicted from Ks light-curvephys.abund.FefloatDist[0.7/18.6] Heliocentric distancekpcpos.distancefloatM17Display data from Minniti+, 2017, J/AJ/153/179, within 0.5"meta.ref.urlintnullableVVV2Display the VVV -DR2 data (II/348) within 0.5"meta.ref.urlcharLCInteractive Plotmeta.ref.urlcharJ/ApJ/857/54/table2JHKs photometric time-series of the candidate RR Lyrae stars with score >0.6Seq[1/1892] Identifiermeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFiltFilter of the VISTA photometric systemmeta.notecharJD[55226.7/57248.6] Heliocentric Julian Date; JD-2455000dtime.epochdoubleindexedmag[10.6/19.5] Apparent magnitude in Filtmagphot.magfloate_mag[0.01/1] Error in mag (1)magstat.error;phot.magfloatZPErr[0.01/1] Magnitude zero-point errormagstat.errorfloat